Magnetocardiography: The measurement of magnetic fields generated by electric currents from the heart. The measurement of these fields provides information which is complementary to that provided by ELECTROCARDIOGRAPHY.ReadingCircadian Rhythm: The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs and stimuli, hormone secretion, sleeping, and feeding.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Antihypertensive Agents: Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.Hypertension: Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.Pressure: A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Blood Circulation: The movement of the BLOOD as it is pumped through the CARDIOVASCULAR SYSTEM.Low Back Pain: Acute or chronic pain in the lumbar or sacral regions, which may be associated with musculo-ligamentous SPRAINS AND STRAINS; INTERVERTEBRAL DISK DISPLACEMENT; and other conditions.Back Pain: Acute or chronic pain located in the posterior regions of the THORAX; LUMBOSACRAL REGION; or the adjacent regions.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Blood Circulation Time: Determination of the shortest time interval between the injection of a substance in the vein and its arrival at some distant site in sufficient concentration to produce a recognizable end result. It represents approximately the inverse of the average velocity of blood flow between two points.Drugs, Chinese Herbal: Chinese herbal or plant extracts which are used as drugs to treat diseases or promote general well-being. The concept does not include synthesized compounds manufactured in China.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Phytotherapy: Use of plants or herbs to treat diseases or to alleviate pain.Tanacetum parthenium: An aromatic perennial plant species that has been used to treat migraines, arthritis, and as a febrifuge. It contains TANNINS, volatile oils (OILS, ESSENTIAL), and sesquiterpene lactones, especially parthenolide.Herb-Drug Interactions: The effect of herbs, other PLANTS, or PLANT EXTRACTS on the activity, metabolism, or toxicity of drugs.Medicine, Chinese Traditional: A system of traditional medicine which is based on the beliefs and practices of the Chinese culture.Cell Death: The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.Cause of Death: Factors which produce cessation of all vital bodily functions. They can be analyzed from an epidemiologic viewpoint.Extracorporeal Circulation: Diversion of blood flow through a circuit located outside the body but continuous with the bodily circulation.Pulmonary Circulation: The circulation of the BLOOD through the LUNGS.Tissue and Organ Procurement: The administrative procedures involved with acquiring TISSUES or organs for TRANSPLANTATION through various programs, systems, or organizations. These procedures include obtaining consent from TISSUE DONORS and arranging for transportation of donated tissues and organs, after TISSUE HARVESTING, to HOSPITALS for processing and transplantation.Organ Transplantation: Transference of an organ between individuals of the same species or between individuals of different species.Respiratory Distress Syndrome, Adult: A syndrome characterized by progressive life-threatening RESPIRATORY INSUFFICIENCY in the absence of known LUNG DISEASES, usually following a systemic insult such as surgery or major TRAUMA.Veins: The vessels carrying blood away from the capillary beds.Vena Cava, Inferior: The venous trunk which receives blood from the lower extremities and from the pelvic and abdominal organs.Femoral Vein: The vein accompanying the femoral artery in the same sheath; it is a continuation of the popliteal vein and becomes the external iliac vein.Pulmonary Disease, Chronic Obstructive: A disease of chronic diffuse irreversible airflow obstruction. Subcategories of COPD include CHRONIC BRONCHITIS and PULMONARY EMPHYSEMA.Illusions: The misinterpretation of a real external, sensory experience.Cold Temperature: An absence of warmth or heat or a temperature notably below an accustomed norm.Anemia, Hemolytic, Autoimmune: Acquired hemolytic anemia due to the presence of AUTOANTIBODIES which agglutinate or lyse the patient's own RED BLOOD CELLS.Hand: The distal part of the arm beyond the wrist in humans and primates, that includes the palm, fingers, and thumb.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.Stroke: A group of pathological conditions characterized by sudden, non-convulsive loss of neurological function due to BRAIN ISCHEMIA or INTRACRANIAL HEMORRHAGES. Stroke is classified by the type of tissue NECROSIS, such as the anatomic location, vasculature involved, etiology, age of the affected individual, and hemorrhagic vs. non-hemorrhagic nature. (From Adams et al., Principles of Neurology, 6th ed, pp777-810)Carbon Disulfide: A colorless, flammable, poisonous liquid, CS2. It is used as a solvent, and is a counterirritant and has local anesthetic properties but is not used as such. It is highly toxic with pronounced CNS, hematologic, and dermatologic effects.Ischemic Attack, Transient: Brief reversible episodes of focal, nonconvulsive ischemic dysfunction of the brain having a duration of less than 24 hours, and usually less than one hour, caused by transient thrombotic or embolic blood vessel occlusion or stenosis. Events may be classified by arterial distribution, temporal pattern, or etiology (e.g., embolic vs. thrombotic). (From Adams et al., Principles of Neurology, 6th ed, pp814-6)Dizziness: An imprecise term which may refer to a sense of spatial disorientation, motion of the environment, or lightheadedness.Brain Ischemia: Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cerebrovascular Disorders: A spectrum of pathological conditions of impaired blood flow in the brain. They can involve vessels (ARTERIES or VEINS) in the CEREBRUM, the CEREBELLUM, and the BRAIN STEM. Major categories include INTRACRANIAL ARTERIOVENOUS MALFORMATIONS; BRAIN ISCHEMIA; CEREBRAL HEMORRHAGE; and others.India2,3-Diketogulonic Acid: Metabolite of ASCORBIC ACID and the oxidized form of the lactone DEHYDROASCORBIC ACID.Caffeine: A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.Tea: The infusion of leaves of CAMELLIA SINENSIS (formerly Thea sinensis) as a beverage, the familiar Asian tea, which contains CATECHIN (especially epigallocatechin gallate) and CAFFEINE.Cardiovascular Diseases: Pathological conditions involving the CARDIOVASCULAR SYSTEM including the HEART; the BLOOD VESSELS; or the PERICARDIUM.Thinking: Mental activity, not predominantly perceptual, by which one apprehends some aspect of an object or situation based on past learning and experience.Human Body: The human being as a non-anatomical and non-zoological entity. The emphasis is on the philosophical or artistic treatment of the human being, and includes lay and social attitudes toward the body in history. (From J. Cassedy, NLM History of Medicine Division)History, 17th Century: Time period from 1601 through 1700 of the common era.Portraits as Topic: Graphic representations, especially of the face, of real persons, usually posed, living or dead. (From Thesaurus for Graphic Materials II, p540, 1995)History, 16th Century: Time period from 1501 through 1600 of the common era.Williams Syndrome: A disorder caused by hemizygous microdeletion of about 28 genes on chromosome 7q11.23, including the ELASTIN gene. Clinical manifestations include SUPRAVALVULAR AORTIC STENOSIS; MENTAL RETARDATION; elfin facies; impaired visuospatial constructive abilities; and transient HYPERCALCEMIA in infancy. The condition affects both sexes, with onset at birth or in early infancy.Harvey murine sarcoma virus: A replication-defective mouse sarcoma virus (SARCOMA VIRUSES, MURINE) first described by J.J. Harvey in 1964.BooksSarcoma Viruses, Murine: A group of replication-defective viruses, in the genus GAMMARETROVIRUS, which are capable of transforming cells, but which replicate and produce tumors only in the presence of Murine leukemia viruses (LEUKEMIA VIRUS, MURINE).