Body Fluid Compartments: The two types of spaces between which water and other body fluids are distributed: extracellular and intracellular.Aortopulmonary Septal Defect: A developmental abnormality in which the spiral (aortopulmonary) septum failed to completely divide the TRUNCUS ARTERIOSUS into ASCENDING AORTA and PULMONARY ARTERY. This abnormal communication between the two major vessels usually lies above their respective valves (AORTIC VALVE; PULMONARY VALVE).Body Fluids: Liquid components of living organisms.Body Water: Fluids composed mainly of water found within the body.Extracellular Fluid: The fluid of the body that is outside of CELLS. It is the external environment for the cells.Extracellular Space: Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.Renin: A highly specific (Leu-Leu) endopeptidase that generates ANGIOTENSIN I from its precursor ANGIOTENSINOGEN, leading to a cascade of reactions which elevate BLOOD PRESSURE and increase sodium retention by the kidney in the RENIN-ANGIOTENSIN SYSTEM. The enzyme was formerly listed as EC 3.4.99.19.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Blepharospasm: Excessive winking; tonic or clonic spasm of the orbicularis oculi muscle.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.Glomerular Filtration Rate: The volume of water filtered out of plasma through glomerular capillary walls into Bowman's capsules per unit of time. It is considered to be equivalent to INULIN clearance.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Plasma Volume: Volume of PLASMA in the circulation. It is usually measured by INDICATOR DILUTION TECHNIQUES.Blogging: Using an INTERNET based personal journal which may consist of reflections, comments, and often hyperlinks.Dipteryx: A plant genus of the family FABACEAE. Members contain COUMARINS.Educational Technology: Systematic identification, development, organization, or utilization of educational resources and the management of these processes. It is occasionally used also in a more limited sense to describe the use of equipment-oriented techniques or audiovisual aids in educational settings. (Thesaurus of ERIC Descriptors, December 1993, p132)Hydrodynamics: The motion of fluids, especially noncompressible liquids, under the influence of internal and external forces.Water-Electrolyte Imbalance: Disturbances in the body's WATER-ELECTROLYTE BALANCE.Hypernatremia: Excessive amount of sodium in the blood. (Dorland, 27th ed)Hyponatremia: Deficiency of sodium in the blood; salt depletion. (Dorland, 27th ed)Water-Electrolyte Balance: The balance of fluid in the BODY FLUID COMPARTMENTS; total BODY WATER; BLOOD VOLUME; EXTRACELLULAR SPACE; INTRACELLULAR SPACE, maintained by processes in the body that regulate the intake and excretion of WATER and ELECTROLYTES, particularly SODIUM and POTASSIUM.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Hypokalemia: Abnormally low potassium concentration in the blood. It may result from potassium loss by renal secretion or by the gastrointestinal route, as by vomiting or diarrhea. It may be manifested clinically by neuromuscular disorders ranging from weakness to paralysis, by electrocardiographic abnormalities (depression of the T wave and elevation of the U wave), by renal disease, and by gastrointestinal disorders. (Dorland, 27th ed)Illusions: The misinterpretation of a real external, sensory experience.Light Signal Transduction: The conversion of absorbed light energy into molecular signals.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Confidentiality: The privacy of information and its protection against unauthorized disclosure.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Informed Consent: Voluntary authorization, by a patient or research subject, with full comprehension of the risks involved, for diagnostic or investigative procedures, and for medical and surgical treatment.Science: The study of natural phenomena by observation, measurement, and experimentation.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.Sports Medicine: The field of medicine concerned with physical fitness and the diagnosis and treatment of injuries sustained in exercise and sports activities.Astronauts: Members of spacecraft crew including those who travel in space, and those in training for space flight. (From Webster, 10th ed; Jane's Aerospace Dictionary, 3d ed)Space Flight: Travel beyond the earth's atmosphere.Biology: One of the BIOLOGICAL SCIENCE DISCIPLINES concerned with the origin, structure, development, growth, function, genetics, and reproduction of animals, plants, and microorganisms.Flight, Animal: The use of wings or wing-like appendages to remain aloft and move through the air.Leeches: Annelids of the class Hirudinea. Some species, the bloodsuckers, may become temporarily parasitic upon animals, including man. Medicinal leeches (HIRUDO MEDICINALIS) have been used therapeutically for drawing blood since ancient times.Weightlessness: Condition in which no acceleration, whether due to gravity or any other force, can be detected by an observer within a system. It also means the absence of weight or the absence of the force of gravity acting on a body. Microgravity, gravitational force between 0 and 10 -6 g, is included here. (From NASA Thesaurus, 1988)Atrial Function: The hemodynamic and electrophysiological action of the HEART ATRIA.Animal Testing Alternatives: Procedures, such as TISSUE CULTURE TECHNIQUES; mathematical models; etc., when used or advocated for use in place of the use of animals in research or diagnostic laboratories.Animal Welfare: The protection of animals in laboratories or other specific environments by promoting their health through better nutrition, housing, and care.Animal Experimentation: The use of animals as investigational subjects.Animals, LaboratoryAnimal Use Alternatives: Alternatives to the use of animals in research, testing, and education. The alternatives may include reduction in the number of animals used, replacement of animals with a non-animal model or with animals of a species lower phylogenetically, or refinement of methods to minimize pain and distress of animals used.Animal Care Committees: Institutional committees established to protect the welfare of animals used in research and education. The 1971 NIH Guide for the Care and Use of Laboratory Animals introduced the policy that institutions using warm-blooded animals in projects supported by NIH grants either be accredited by a recognized professional laboratory animal accrediting body or establish its own committee to evaluate animal care; the Public Health Service adopted a policy in 1979 requiring such committees; and the 1985 amendments to the Animal Welfare Act mandate review and approval of federally funded research with animals by a formally designated Institutional Animal Care and Use Committee (IACUC).Toxicity Tests: An array of tests used to determine the toxicity of a substance to living systems. These include tests on clinical drugs, foods, and environmental pollutants.Postural Balance: A POSTURE in which an ideal body mass distribution is achieved. Postural balance provides the body carriage stability and conditions for normal functions in stationary position or in movement, such as sitting, standing, or walking.Sensation: The process in which specialized SENSORY RECEPTOR CELLS transduce peripheral stimuli (physical or chemical) into NERVE IMPULSES which are then transmitted to the various sensory centers in the CENTRAL NERVOUS SYSTEM.Proprioception: Sensory functions that transduce stimuli received by proprioceptive receptors in joints, tendons, muscles, and the INNER EAR into neural impulses to be transmitted to the CENTRAL NERVOUS SYSTEM. Proprioception provides sense of stationary positions and movements of one's body parts, and is important in maintaining KINESTHESIA and POSTURAL BALANCE.Sensation Disorders: Disorders of the special senses (i.e., VISION; HEARING; TASTE; and SMELL) or somatosensory system (i.e., afferent components of the PERIPHERAL NERVOUS SYSTEM).Posture: The position or attitude of the body.Clinical Trials as Topic: Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.Orientation: Awareness of oneself in relation to time, place and person.