Fatigue: The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.Anemia: A reduction in the number of circulating ERYTHROCYTES or in the quantity of HEMOGLOBIN.Muscle Fatigue: A state arrived at through prolonged and strong contraction of a muscle. Studies in athletes during prolonged submaximal exercise have shown that muscle fatigue increases in almost direct proportion to the rate of muscle glycogen depletion. Muscle fatigue in short-term maximal exercise is associated with oxygen lack and an increased level of blood and muscle lactic acid, and an accompanying increase in hydrogen-ion concentration in the exercised muscle.Fatigue Syndrome, Chronic: A syndrome characterized by persistent or recurrent fatigue, diffuse musculoskeletal pain, sleep disturbances, and subjective cognitive impairment of 6 months duration or longer. Symptoms are not caused by ongoing exertion; are not relieved by rest; and result in a substantial reduction of previous levels of occupational, educational, social, or personal activities. Minor alterations of immune, neuroendocrine, and autonomic function may be associated with this syndrome. There is also considerable overlap between this condition and FIBROMYALGIA. (From Semin Neurol 1998;18(2):237-42; Ann Intern Med 1994 Dec 15;121(12): 953-9)Mental Fatigue: A condition of low alertness or cognitive impairment, usually associated with prolonged mental activities or stress.Anemia, Aplastic: A form of anemia in which the bone marrow fails to produce adequate numbers of peripheral blood elements.Anemia, Hemolytic: A condition of inadequate circulating red blood cells (ANEMIA) or insufficient HEMOGLOBIN due to premature destruction of red blood cells (ERYTHROCYTES).Fanconi Anemia: Congenital disorder affecting all bone marrow elements, resulting in ANEMIA; LEUKOPENIA; and THROMBOPENIA, and associated with cardiac, renal, and limb malformations as well as dermal pigmentary changes. Spontaneous CHROMOSOME BREAKAGE is a feature of this disease along with predisposition to LEUKEMIA. There are at least 7 complementation groups in Fanconi anemia: FANCA, FANCB, FANCC, FANCD1, FANCD2, FANCE, FANCF, FANCG, and FANCL. (from Online Mendelian Inheritance in Man, http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=227650, August 20, 2004)Anemia, Hemolytic, Autoimmune: Acquired hemolytic anemia due to the presence of AUTOANTIBODIES which agglutinate or lyse the patient's own RED BLOOD CELLS.Anemia, Hypochromic: Anemia characterized by a decrease in the ratio of the weight of hemoglobin to the volume of the erythrocyte, i.e., the mean corpuscular hemoglobin concentration is less than normal. The individual cells contain less hemoglobin than they could have under optimal conditions. Hypochromic anemia may be caused by iron deficiency from a low iron intake, diminished iron absorption, or excessive iron loss. It can also be caused by infections or other diseases, therapeutic drugs, lead poisoning, and other conditions. (Stedman, 25th ed; from Miale, Laboratory Medicine: Hematology, 6th ed, p393)Anemia, Macrocytic: Anemia characterized by larger than normal erythrocytes, increased mean corpuscular volume (MCV) and increased mean corpuscular hemoglobin (MCH).Anemia, Pernicious: A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B 12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. (Dorland, 27th ed)Anemia, Sickle Cell: A disease characterized by chronic hemolytic anemia, episodic painful crises, and pathologic involvement of many organs. It is the clinical expression of homozygosity for hemoglobin S.Anemia, Sideroblastic: Anemia characterized by the presence of erythroblasts containing excessive deposits of iron in the marrow.Anemia, Megaloblastic: A disorder characterized by the presence of ANEMIA, abnormally large red blood cells (megalocytes or macrocytes), and MEGALOBLASTS.Hemoglobins: The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.Infectious Anemia Virus, Equine: A species of LENTIVIRUS, subgenus equine lentiviruses (LENTIVIRUSES, EQUINE), causing acute and chronic infection in horses. It is transmitted mechanically by biting flies, mosquitoes, and midges, and iatrogenically through unsterilized equipment. Chronic infection often consists of acute episodes with remissions.Anemia, Refractory: A severe sometimes chronic anemia, usually macrocytic in type, that does not respond to ordinary antianemic therapy.Anemia, Hemolytic, Congenital: Hemolytic anemia due to various intrinsic defects of the erythrocyte.Erythropoietin: Glycoprotein hormone, secreted chiefly by the KIDNEY in the adult and the LIVER in the FETUS, that acts on erythroid stem cells of the BONE MARROW to stimulate proliferation and differentiation.Equine Infectious Anemia: Viral disease of horses caused by the equine infectious anemia virus (EIAV; INFECTIOUS ANEMIA VIRUS, EQUINE). It is characterized by intermittent fever, weakness, and anemia. Chronic infection consists of acute episodes with remissions.Chicken anemia virus: The type species of GYROVIRUS, a small, non-enveloped DNA virus originally isolated from contaminated vaccines in Japan. It causes chicken infectious anemia and may possibly play a key role in hemorrhagic anemia syndrome, anemia dermatitis, and blue wing disease.Anemia, Dyserythropoietic, Congenital: A familial disorder characterized by ANEMIA with multinuclear ERYTHROBLASTS, karyorrhexis, asynchrony of nuclear and cytoplasmic maturation, and various nuclear abnormalities of bone marrow erythrocyte precursors (ERYTHROID PRECURSOR CELLS). Type II is the most common of the 3 types; it is often referred to as HEMPAS, based on the Hereditary Erythroblast Multinuclearity with Positive Acidified Serum test.Anemia, Diamond-Blackfan: A rare congenital hypoplastic anemia that usually presents early in infancy. The disease is characterized by a moderate to severe macrocytic anemia, occasional neutropenia or thrombocytosis, a normocellular bone marrow with erythroid hypoplasia, and an increased risk of developing leukemia. (Curr Opin Hematol 2000 Mar;7(2):85-94)Fanconi Anemia Complementation Group Proteins: A diverse group of proteins whose genetic MUTATIONS have been associated with the chromosomal instability syndrome FANCONI ANEMIA. Many of these proteins play important roles in protecting CELLS against OXIDATIVE STRESS.Iron: A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.Hematinics: Agents which improve the quality of the blood, increasing the hemoglobin level and the number of erythrocytes. They are used in the treatment of anemias.Pregnancy Complications, Hematologic: The co-occurrence of pregnancy and a blood disease (HEMATOLOGIC DISEASES) which involves BLOOD CELLS or COAGULATION FACTORS. The hematologic disease may precede or follow FERTILIZATION and it may or may not have a deleterious effect on the pregnant woman or FETUS.Anemia, Neonatal: The mildest form of erythroblastosis fetalis in which anemia is the chief manifestation.Anemia, Refractory, with Excess of Blasts: Chronic refractory anemia with granulocytopenia, and/or thrombocytopenia. Myeloblasts and progranulocytes constitute 5 to 40 percent of the nucleated marrow cells.Hematocrit: The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.Severity of Illness Index: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.Fanconi Anemia Complementation Group C Protein: A Fanconi anemia complementation group protein that regulates the activities of CYTOCHROME P450 REDUCTASE and GLUTATHIONE S-TRANSFERASE. It is found predominately in the CYTOPLASM, but moves to the CELL NUCLEUS in response to FANCE PROTEIN.Quality of Life: A generic concept reflecting concern with the modification and enhancement of life attributes, e.g., physical, political, moral and social environment; the overall condition of a human life.Fanconi Anemia Complementation Group D2 Protein: A Fanconi anemia complementation group protein that undergoes mono-ubiquitination by FANCL PROTEIN in response to DNA DAMAGE. Also, in response to IONIZING RADIATION it can undergo PHOSPHORYLATION by ataxia telangiectasia mutated protein. Modified FANCD2 interacts with BRCA2 PROTEIN in a stable complex with CHROMATIN, and it is involved in DNA REPAIR by homologous RECOMBINATION.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Fanconi Anemia Complementation Group A Protein: A Fanconi anemia complementation group protein that is the most commonly mutated protein in FANCONI ANEMIA. It undergoes PHOSPHORYLATION by PROTEIN KINASE B and forms a complex with FANCC PROTEIN in the CELL NUCLEUS.Erythropoiesis: The production of red blood cells (ERYTHROCYTES). In humans, erythrocytes are produced by the YOLK SAC in the first trimester; by the liver in the second trimester; by the BONE MARROW in the third trimester and after birth. In normal individuals, the erythrocyte count in the peripheral blood remains relatively constant implying a balance between the rate of erythrocyte production and rate of destruction.Muscle Contraction: A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.Muscle, Skeletal: A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.Isometric Contraction: Muscular contractions characterized by increase in tension without change in length.Ferritins: Iron-containing proteins that are widely distributed in animals, plants, and microorganisms. Their major function is to store IRON in a nontoxic bioavailable form. Each ferritin molecule consists of ferric iron in a hollow protein shell (APOFERRITINS) made of 24 subunits of various sequences depending on the species and tissue types.Anemia, Hemolytic, Congenital Nonspherocytic: Any one of a group of congenital hemolytic anemias in which there is no abnormal hemoglobin or spherocytosis and in which there is a defect of glycolysis in the erythrocyte. Common causes include deficiencies in GLUCOSE-6-PHOSPHATE ISOMERASE; PYRUVATE KINASE; and GLUCOSE-6-PHOSPHATE DEHYDROGENASE.Pallor: A clinical manifestation consisting of an unnatural paleness of the skin.Erythrocyte Count: The number of RED BLOOD CELLS per unit volume in a sample of venous BLOOD.Erythrocyte Indices: ERYTHROCYTE size and HEMOGLOBIN content or concentration, usually derived from ERYTHROCYTE COUNT; BLOOD hemoglobin concentration; and HEMATOCRIT. The indices include the mean corpuscular volume (MCV), the mean corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC).Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Physical Endurance: The time span between the beginning of physical activity by an individual and the termination because of exhaustion.Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Hemoglobinometry: Measurement of hemoglobin concentration in blood.Blood Transfusion: The introduction of whole blood or blood component directly into the blood stream. (Dorland, 27th ed)Sleep Disorders: Conditions characterized by disturbances of usual sleep patterns or behaviors. Sleep disorders may be divided into three major categories: DYSSOMNIAS (i.e. disorders characterized by insomnia or hypersomnia), PARASOMNIAS (abnormal sleep behaviors), and sleep disorders secondary to medical or psychiatric disorders. (From Thorpy, Sleep Disorders Medicine, 1994, p187)Fibromyalgia: A common nonarticular rheumatic syndrome characterized by myalgia and multiple points of focal muscle tenderness to palpation (trigger points). Muscle pain is typically aggravated by inactivity or exposure to cold. This condition is often associated with general symptoms, such as sleep disturbances, fatigue, stiffness, HEADACHES, and occasionally DEPRESSION. There is significant overlap between fibromyalgia and the chronic fatigue syndrome (FATIGUE SYNDROME, CHRONIC). Fibromyalgia may arise as a primary or secondary disease process. It is most frequent in females aged 20 to 50 years. (From Adams et al., Principles of Neurology, 6th ed, p1494-95)Chronic Disease: Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care. (Dictionary of Health Services Management, 2d ed)Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Fanconi Anemia Complementation Group G Protein: A Fanconi anemia complementation group protein that undergoes PHOSPHORYLATION by CDC2 PROTEIN KINASE during MITOSIS. It forms a complex with other FANCONI ANEMIA PROTEINS and helps protect CELLS from DNA DAMAGE by genotoxic agents.Coombs Test: A test to detect non-agglutinating ANTIBODIES against ERYTHROCYTES by use of anti-antibodies (the Coombs' reagent.) The direct test is applied to freshly drawn blood to detect antibody bound to circulating red cells. The indirect test is applied to serum to detect the presence of antibodies that can bind to red blood cells.Electromyography: Recording of the changes in electric potential of muscle by means of surface or needle electrodes.Reticulocyte Count: The number of RETICULOCYTES per unit volume of BLOOD. The values are expressed as a percentage of the ERYTHROCYTE COUNT or in the form of an index ("corrected reticulocyte index"), which attempts to account for the number of circulating erythrocytes.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Depression: Depressive states usually of moderate intensity in contrast with major depression present in neurotic and psychotic disorders.Asthenopia: Term generally used to describe complaints related to refractive error, ocular muscle imbalance, including pain or aching around the eyes, burning and itchiness of the eyelids, ocular fatigue, and headaches.Iron, Dietary: Iron or iron compounds used in foods or as food. Dietary iron is important in oxygen transport and the synthesis of the iron-porphyrin proteins hemoglobin, myoglobin, cytochromes, and cytochrome oxidase. Insufficient amounts of dietary iron can lead to iron-deficiency anemia.Cross-Sectional Studies: Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Iron Compounds: Organic and inorganic compounds that contain iron as an integral part of the molecule.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Hepcidins: Forms of hepcidin, a cationic amphipathic peptide synthesized in the liver as a prepropeptide which is first processed into prohepcidin and then into the biologically active hepcidin forms, including in human the 20-, 22-, and 25-amino acid residue peptide forms. Hepcidin acts as a homeostatic regulators of iron metabolism and also possesses antimicrobial activity.Torque: The rotational force about an axis that is equal to the product of a force times the distance from the axis where the force is applied.Erythrocytes, Abnormal: Oxygen-carrying RED BLOOD CELLS in mammalian blood that are abnormal in structure or function.Exercise: Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.Erythrocyte Transfusion: The transfer of erythrocytes from a donor to a recipient or reinfusion to the donor.Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Drug Administration Schedule: Time schedule for administration of a drug in order to achieve optimum effectiveness and convenience.Diaphragm: The musculofibrous partition that separates the THORACIC CAVITY from the ABDOMINAL CAVITY. Contraction of the diaphragm increases the volume of the thoracic cavity aiding INHALATION.Vitamin B 12 Deficiency: A nutritional condition produced by a deficiency of VITAMIN B 12 in the diet, characterized by megaloblastic anemia. Since vitamin B 12 is not present in plants, humans have obtained their supply from animal products, from multivitamin supplements in the form of pills, and as additives to food preparations. A wide variety of neuropsychiatric abnormalities is also seen in vitamin B 12 deficiency and appears to be due to an undefined defect involving myelin synthesis. (From Cecil Textbook of Medicine, 19th ed, p848)Bone Marrow: The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.Erythrocyte Aging: The senescence of RED BLOOD CELLS. Lacking the organelles that make protein synthesis possible, the mature erythrocyte is incapable of self-repair, reproduction, and carrying out certain functions performed by other cells. This limits the average life span of an erythrocyte to 120 days.Physical Exertion: Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.beta-Thalassemia: A disorder characterized by reduced synthesis of the beta chains of hemoglobin. There is retardation of hemoglobin A synthesis in the heterozygous form (thalassemia minor), which is asymptomatic, while in the homozygous form (thalassemia major, Cooley's anemia, Mediterranean anemia, erythroblastic anemia), which can result in severe complications and even death, hemoglobin A synthesis is absent.Muscle Strength: The amount of force generated by MUSCLE CONTRACTION. Muscle strength can be measured during isometric, isotonic, or isokinetic contraction, either manually or using a device such as a MUSCLE STRENGTH DYNAMOMETER.Isavirus: A genus in the family ORTHOMYXOVIRIDAE containing one species: Infectious salmon anemia virus.Pancytopenia: Deficiency of all three cell elements of the blood, erythrocytes, leukocytes and platelets.Postpoliomyelitis Syndrome: A syndrome characterized by new neuromuscular symptoms that occur at least 15 years after clinical stability has been attained in patients with a prior history of symptomatic poliomyelitis. Clinical features include new muscular weakness and atrophy of the limbs, bulbar innervated musculature, and muscles of respiration, combined with excessive fatigue, joint pain, and reduced stamina. The process is marked by slow progression and periods of stabilization. (From Ann NY Acad Sci 1995 May 25;753:68-80)Electric Stimulation: Use of electric potential or currents to elicit biological responses.Neurasthenia: A mental disorder characterized by chronic fatigue and concomitant physiologic symptoms.Thalassemia: A group of hereditary hemolytic anemias in which there is decreased synthesis of one or more hemoglobin polypeptide chains. There are several genetic types with clinical pictures ranging from barely detectable hematologic abnormality to severe and fatal anemia.Survivors: Persons who have experienced a prolonged survival after serious disease or who continue to live with a usually life-threatening condition as well as family members, significant others, or individuals surviving traumatic life events.Fanconi Anemia Complementation Group F Protein: A Fanconi anemia complementation group protein. It is an essential component of a nuclear core complex that protects the GENOME against CHROMOSOMAL INSTABILITY. It interacts directly with FANCG PROTEIN and helps stabilize a complex with FANCA PROTEIN and FANCC PROTEIN.Phenylhydrazines: Diazo derivatives of aniline, used as a reagent for sugars, ketones, and aldehydes. (Dorland, 28th ed)Recombinant Proteins: Proteins prepared by recombinant DNA technology.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Fanconi Anemia Complementation Group E Protein: A Fanconi anemia complementation group protein that interacts with FANCC PROTEIN and FANCD2 PROTEIN. It promotes the accumulation of FANCC protein in the CELL NUCLEUS.Work Schedule Tolerance: Physiological or psychological effects of periods of work which may be fixed or flexible such as flexitime, work shifts, and rotating shifts.Fetal Hemoglobin: The major component of hemoglobin in the fetus. This HEMOGLOBIN has two alpha and two gamma polypeptide subunits in comparison to normal adult hemoglobin, which has two alpha and two beta polypeptide subunits. Fetal hemoglobin concentrations can be elevated (usually above 0.5%) in children and adults affected by LEUKEMIA and several types of ANEMIA.Horses: Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Malaria: A protozoan disease caused in humans by four species of the PLASMODIUM genus: PLASMODIUM FALCIPARUM; PLASMODIUM VIVAX; PLASMODIUM OVALE; and PLASMODIUM MALARIAE; and transmitted by the bite of an infected female mosquito of the genus ANOPHELES. Malaria is endemic in parts of Asia, Africa, Central and South America, Oceania, and certain Caribbean islands. It is characterized by extreme exhaustion associated with paroxysms of high FEVER; SWEATING; shaking CHILLS; and ANEMIA. Malaria in ANIMALS is caused by other species of plasmodia.Blood Cell Count: The number of LEUKOCYTES and ERYTHROCYTES per unit volume in a sample of venous BLOOD. A complete blood count (CBC) also includes measurement of the HEMOGLOBIN; HEMATOCRIT; and ERYTHROCYTE INDICES.Thrombocytopenia: A subnormal level of BLOOD PLATELETS.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Folic Acid Deficiency: A nutritional condition produced by a deficiency of FOLIC ACID in the diet. Many plant and animal tissues contain folic acid, abundant in green leafy vegetables, yeast, liver, and mushrooms but destroyed by long-term cooking. Alcohol interferes with its intermediate metabolism and absorption. Folic acid deficiency may develop in long-term anticonvulsant therapy or with use of oral contraceptives. This deficiency causes anemia, macrocytic anemia, and megaloblastic anemia. It is indistinguishable from vitamin B 12 deficiency in peripheral blood and bone marrow findings, but the neurologic lesions seen in B 12 deficiency do not occur. (Merck Manual, 16th ed)Kidney Failure, Chronic: The end-stage of CHRONIC RENAL INSUFFICIENCY. It is characterized by the severe irreversible kidney damage (as measured by the level of PROTEINURIA) and the reduction in GLOMERULAR FILTRATION RATE to less than 15 ml per min (Kidney Foundation: Kidney Disease Outcome Quality Initiative, 2002). These patients generally require HEMODIALYSIS or KIDNEY TRANSPLANTATION.Cohort Studies: Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.Ferrous Compounds: Inorganic or organic compounds that contain divalent iron.Antineoplastic Agents: Substances that inhibit or prevent the proliferation of NEOPLASMS.Quadriceps Muscle: The quadriceps femoris. A collective name of the four-headed skeletal muscle of the thigh, comprised of the rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis.Sleep: A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility.Double-Blind Method: A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.Vitamin B 12: A cobalt-containing coordination compound produced by intestinal micro-organisms and found also in soil and water. Higher plants do not concentrate vitamin B 12 from the soil and so are a poor source of the substance as compared with animal tissues. INTRINSIC FACTOR is important for the assimilation of vitamin B 12.Splenomegaly: Enlargement of the spleen.Parvovirus B19, Human: The type species of ERYTHROVIRUS and the etiological agent of ERYTHEMA INFECTIOSUM, a disease most commonly seen in school-age children.Antineoplastic Combined Chemotherapy Protocols: The use of two or more chemicals simultaneously or sequentially in the drug therapy of neoplasms. The drugs need not be in the same dosage form.Erythroblasts: Immature, nucleated ERYTHROCYTES occupying the stage of ERYTHROPOIESIS that follows formation of ERYTHROID PRECURSOR CELLS and precedes formation of RETICULOCYTES. The normal series is called normoblasts. Cells called MEGALOBLASTS are a pathologic series of erythroblasts.Comorbidity: The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.Multiple Sclerosis: An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)Exercise Tolerance: The exercise capacity of an individual as measured by endurance (maximal exercise duration and/or maximal attained work load) during an EXERCISE TEST.Materials Testing: The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.Dietary Supplements: Products in capsule, tablet or liquid form that provide dietary ingredients, and that are intended to be taken by mouth to increase the intake of nutrients. Dietary supplements can include macronutrients, such as proteins, carbohydrates, and fats; and/or MICRONUTRIENTS, such as VITAMINS; MINERALS; and PHYTOCHEMICALS.Activities of Daily Living: The performance of the basic activities of self care, such as dressing, ambulation, or eating.Pain Measurement: Scales, questionnaires, tests, and other methods used to assess pain severity and duration in patients or experimental animals to aid in diagnosis, therapy, and physiological studies.Osmotic Fragility: RED BLOOD CELL sensitivity to change in OSMOTIC PRESSURE. When exposed to a hypotonic concentration of sodium in a solution, red cells take in more water, swell until the capacity of the cell membrane is exceeded, and burst.Reticulocytes: Immature ERYTHROCYTES. In humans, these are ERYTHROID CELLS that have just undergone extrusion of their CELL NUCLEUS. They still contain some organelles that gradually decrease in number as the cells mature. RIBOSOMES are last to disappear. Certain staining techniques cause components of the ribosomes to precipitate into characteristic "reticulum" (not the same as the ENDOPLASMIC RETICULUM), hence the name reticulocytes.Fractures, Stress: Fractures due to the strain caused by repetitive exercise. They are thought to arise from a combination of MUSCLE FATIGUE and bone failure, and occur in situations where BONE REMODELING predominates over repair. The most common sites of stress fractures are the METATARSUS; FIBULA; TIBIA; and FEMORAL NECK.Antilymphocyte Serum: Serum containing GAMMA-GLOBULINS which are antibodies for lymphocyte ANTIGENS. It is used both as a test for HISTOCOMPATIBILITY and therapeutically in TRANSPLANTATION.Parasitemia: The presence of parasites (especially malarial parasites) in the blood. (Dorland, 27th ed)Anxiety: Feeling or emotion of dread, apprehension, and impending disaster but not disabling as with ANXIETY DISORDERS.Longitudinal Studies: Studies in which variables relating to an individual or group of individuals are assessed over a period of time.Iron Overload: An excessive accumulation of iron in the body due to a greater than normal absorption of iron from the gastrointestinal tract or from parenteral injection. This may arise from idiopathic hemochromatosis, excessive iron intake, chronic alcoholism, certain types of refractory anemia, or transfusional hemosiderosis. (From Churchill's Illustrated Medical Dictionary, 1989)Knee: A region of the lower extremity immediately surrounding and including the KNEE JOINT.Exercise Therapy: A regimen or plan of physical activities designed and prescribed for specific therapeutic goals. Its purpose is to restore normal musculoskeletal function or to reduce pain caused by diseases or injuries.Mitomycin: An antineoplastic antibiotic produced by Streptomyces caespitosus. It is one of the bi- or tri-functional ALKYLATING AGENTS causing cross-linking of DNA and inhibition of DNA synthesis.Heinz Bodies: Abnormal intracellular inclusions, composed of denatured hemoglobin, found on the membrane of red blood cells. They are seen in thalassemias, enzymopathies, hemoglobinopathies, and after splenectomy.Hookworm Infections: Infection of humans or animals with hookworms other than those caused by the genus Ancylostoma or Necator, for which the specific terms ANCYLOSTOMIASIS and NECATORIASIS are available.Receptors, Transferrin: Membrane glycoproteins found in high concentrations on iron-utilizing cells. They specifically bind iron-bearing transferrin, are endocytosed with its ligand and then returned to the cell surface where transferrin without its iron is released.Hemoglobinopathies: A group of inherited disorders characterized by structural alterations within the hemoglobin molecule.Exercise Test: Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.Hematologic Diseases: Disorders of the blood and blood forming tissues.Disorders of Excessive Somnolence: Disorders characterized by hypersomnolence during normal waking hours that may impair cognitive functioning. Subtypes include primary hypersomnia disorders (e.g., IDIOPATHIC HYPERSOMNOLENCE; NARCOLEPSY; and KLEINE-LEVIN SYNDROME) and secondary hypersomnia disorders where excessive somnolence can be attributed to a known cause (e.g., drug affect, MENTAL DISORDERS, and SLEEP APNEA SYNDROME). (From J Neurol Sci 1998 Jan 8;153(2):192-202; Thorpy, Principles and Practice of Sleep Medicine, 2nd ed, p320)Parvoviridae Infections: Virus infections caused by the PARVOVIRIDAE.Stress, Mechanical: A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.Biomechanical Phenomena: The properties, processes, and behavior of biological systems under the action of mechanical forces.Hemoglobin, Sickle: An abnormal hemoglobin resulting from the substitution of valine for glutamic acid at position 6 of the beta chain of the globin moiety. The heterozygous state results in sickle cell trait, the homozygous in sickle cell anemia.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Malaria, Falciparum: Malaria caused by PLASMODIUM FALCIPARUM. This is the severest form of malaria and is associated with the highest levels of parasites in the blood. This disease is characterized by irregularly recurring febrile paroxysms that in extreme cases occur with acute cerebral, renal, or gastrointestinal manifestations.Psychometrics: Assessment of psychological variables by the application of mathematical procedures.Age Factors: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.Intrinsic Factor: A glycoprotein secreted by the cells of the GASTRIC GLANDS that is required for the absorption of VITAMIN B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to VITAMIN B 12 DEFICIENCY and ANEMIA, PERNICIOUS.alpha-Thalassemia: A disorder characterized by reduced synthesis of the alpha chains of hemoglobin. The severity of this condition can vary from mild anemia to death, depending on the number of genes deleted.
  • Your doctor will say it is normal if it is over 12, but research has shown that in people with chronic fatigue, iron supplementation increased energy dramatically in people with a ferritin under 50 who were not anemic. (vitality101.com)
  • At least 3.4 million Americans have been diagnosed as anemic, and millions more may be undiagnosed or at increased risk of developing anemia. (prlog.org)
  • Although the odd incident of vague symptoms may sometimes be noticed by the anemic patient, it is often ignored and not attributed to anemia. (healthhype.com)
  • The onset is insidious, and the initial symptom is frequently related to anemia or bleeding, although fever or infections may be noted at presentation. (medscape.com)
  • I stumbled upon an article about the use of Moringa oleifera to treat anemia, and thought I had nothing to lose. (feramoringa.com)
  • The present invention teaches using Erythropoetin to treat anemia caused by the combined treatment of Ribavirin and alpha-interferon. (google.com)
  • The drugs epoetin alfa (Eprex, erythropoietin) and darbepoetin (Aranesp) are erythropoietin products that may be given to treat anemia. (cancer.ca)
  • Thyme tea will help you treat anemia and blood disorders. (the-spiritualist.com)
  • Your provider will likely prescribe medicines that help treat anemia caused by chronic kidney disease. (cdc.gov)
  • Anemia is not a disease, but rather a sign of some other unresolved issue in your body that needs thorough diagnosis and fixing. (lifehack.org)
  • Some studies suggest that when your body is fighting an infection that won't go away, it triggers fatigue. (healthline.com)
  • Anemia in CKD can increase your risk of heart problems because the heart has to work harder to provide blood to your body. (kidneyfund.org)
  • People with anemia supply the body sufficiently good blood. (feelingkeep.com)
  • The frequent menstruation especially in combination with anemia leads to a weakened body. (feelingkeep.com)
  • Also, diabetes can cause fatigue, due to insufficient insulin production provides a limited amount of sugar to the body. (feelingkeep.com)
  • Throwing off the natural order of things in your body, having an underactive thyroid can result in weight gain, fatigue, increased susceptibility to cold, a puffy face, heavier than normal menses (which can fuel anemia) and higher than normal cholesterol. (health-local.com)
  • For people getting chemotherapy in cycles, fatigue often gets worse in the first few days and then gets better until the next treatment, when the pattern starts again. (cancer.org)
  • For example, fatigue may be worse at the beginning and end of a chemotherapy treatment cycle and increase throughout the course of radiation treatment. (cancer.ca)
  • Physical fatigue affects your bodily function (hand limb coordination, blinking frequently etc), psychological fatigue affects the cognitive function of your brain (i.e. feeling dizzy, "brain fog" etc). (lifehack.org)
  • 3. A method for treating ribavirin or ribavirin and interferon-alpha induced anemia comprising administering Erythropoietin to a patient in need thereof as a suspension, emulsion, syrup or elixir wherein the ribavirin or ribavirin and interferon-alpha induced anemia is a result of treating said patient in need thereof with a maximum effective dosage of ribavirin wherein said dosage is at or between 800-1200 mg per day. (google.com)