Bohr effect(redirected from Bohr shift)
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Related to Bohr shift: root effect
a result produced by an action.
additive effect the combined effect produced by the action of two or more agents, being equal to the sum of their separate effects.
adverse effect a symptom produced by a drug or therapy that is injurious to the patient.
Bainbridge effect Bainbridge reflex.
Bohr effect decreased affinity of hemoglobin for oxygen caused by an increase of carbon dioxide; the oxyhemoglobin dissociation curve is displaced to the right because of higher partial pressure of carbon dioxide and lower pH. See also Haldane effect.
Crabtree effect the inhibition of oxygen consumption on the addition of glucose to tissues or microorganisms having a high rate of aerobic glycolysis; the converse of the Pasteur effect.
cumulative effect the action of a drug or treatment resulting from repeated use.
Doppler effect see doppler effect.
experimenter e's demand characteristics.
extrapyramidal e's the side effects caused by neuroleptic medications, including dystonias, parkinsonism, akathisia, and tardive dyskinesia.
Haldane effect increased oxygenation of hemoglobin promotes dissociation of carbon dioxide; see also Bohr effect.
Hawthorne effect a psychological response in which the subjects in a research study change their behavior simply because they are subjects in a study, not because of the research treatment.
heel effect variation in x-ray beam intensity and projected focal spot size along the long axis of the x-ray tube from cathode to anode.
parallax effect the position of the image on each emulsion of dual emulsion film; it is accentuated by tube-angled x-ray techniques.
Pasteur effect the decrease in the rate of glycolysis and the suppression of lactate accumulation by tissues or microorganisms in the presence of oxygen.
photoelectric effect ejection of electrons from matter as a result of interaction with photons from high frequency electromagnetic radiation, such as x-rays; the ejected electrons may be energetic enough to ionize multiple additional atoms.
placebo effect the total of all nonspecific effects, both good and adverse, of treatment; it refers primarily to psychological and psychophysiological effects associated with the caregiver-patient relationship and the patient's expectations and apprehensions concerning the treatment. See also placebo.
position effect in genetics, the changed effect produced by alteration of the relative positions of various genes on the chromosomes.
pressure effect the sum of the changes that are due to obstruction of tissue drainage by pressure.
proarrhythmic effect any new, more advanced form of arrhythmia caused by an antiarrhythmic agent, especially those that produce hemodynamically important symptoms. These arrhythmias occur less than 30 days after initiation of treatment and are not due to a new event such as acute myocardial infarction or hypokalemia.
side effect a consequence other than that for which an agent is used, especially an adverse effect on another organ system.
Somogyi effect see somogyi effect.
the influence exerted by carbon dioxide on the oxygen dissociation curve of blood, that is, the curve is shifted to the right, which means an apparent reduction in the affinity of hemoglobin for oxygen. Compare: Haldane effect.
Etymology: Christian Bohr, Danish physiologist, 1855-1911
the effect of CO2 and H+ on the affinity of hemoglobin for molecular O2. Increasing PCO2 and H+ decrease oxyhemoglobin saturation, whereas decreasing concentrations have the opposite effect. In humans a decrease of pH from 7.4 to 7.3 at 40 mm Hg PO2 decreases oxyhemoglobin saturation by 6%. The Bohr effect is particularly significant in the capillaries of working muscles and the myocardium and in maternal and fetal exchange vessels of the placenta.
Bohr effectThe reduction in haemoglobin affinity for O2 caused by a reduction in pH resulting from addition of protons (H+) or CO2 to blood.
Bohr ef·fect(bōr e-fekt')
The product of H+ concentration on the affinity of hemoglobin for oxygen. As the H+ concentration increases, the oxygen affinity decreases, causing a release of more oxygen to the tissue. One of the most important buffer systems in the body.
Bohr shifta phenomenon named after its discoverer, the Danish physiologist Christian Bohr (1855–1911), who showed that the oxygen-carrying capacity of blood HAEMOGLOBIN varies with PH. At high pH values haemoglobin has a high affinity for oxygen, but more acid conditions cause haemoglobin to release its oxygen, as in tissues with a high concentration of dissolved carbon dioxide. See OXYGEN DISSOCIATION CURVE.
Bohr,Christian, Danish physiologist, 1855-1911.
Bohr effect - the influence exerted by carbon dioxide on the oxygen dissociation curve of blood.
Bohr equation - an equation to calculate respiratory dead space.
Bohr effectdescribes a shift of the oxyhaemoglobin dissociation curve to the right, due to an increase in acidity, carbon dioxide tension and/or temperature of the blood; these reduce the percentage saturation of haemoglobin with oxygen, and hence the amount of oxygen carried per litre of blood, at any given oxygen tension.
displacement of the oxyhemoglobin dissociation curve by a change in carbon dioxide tension.