English dictionary of medical terms (02)
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- No:20 - activate
1.to render activity. 2.to become active. 3.to convert (a compound,
as a provitamin or enzyme) into an active form or different
compound, esp. into one that has a particular biological action
(e.g. ergosterol by irradiation to vitamin D2 for use in treating
- No:21 - active
characterized by action; not passive; not expectant.
- No:22 - activity
1. the state of being active; the ability to produce some effect;
the extent of some function or action. 2. a thermodynamic quantity
that represents the effective concentration of a solute in a
nonideal solution; if concentrations are replaced by activities,
the equations for equilibrium constants, electrode potentials,
osmotic pressure, boiling point elevation, freezing point
depression, and vapour pressures of volatile solutes are converted
from approximations that hold only for dilute solutions to exact
equations that hold for all concentrations. The activity is equal
to the product of the concentration and the activity coefficient,
a dimensionless number measuring deviation from nonideality.
Symbol a. 3. radioactivity; the number of disintegrations per unit
time of a radioactive material, measured in curies or becquerels.
Symbol A. 4. optical activity.
- No:23 - acuity
(L. acuitas sharpness) clarity or clearness, especially of the
- No:24 - acute
(L. acutus sharp) 1. sharp, poignant. 2. having a short and
relatively severe course.
- No:25 - adaptation
(L. adaptare to fit) 1. the adjustment of an organism to its
environment, or the process by which it enhances such fitness. 2.
the normal ability of the eye to adjust itself to variations in the
intensity of light; the adjustment to such variations. 3. the
decline in the frequency of firing of a neuron, particularly of a
receptor, under conditions of constant stimulation. 4. in
dentistry, (a) the proper fitting of a denture, (b) the degree of
proximity and interlocking of restorative material to a tooth
preparation, (c) the exact adjustment of bands to teeth. 5. in
microbiology, the adjustment of bacterial physiology to a new
- No:26 - addiction
the state of being given up to some habit, especially strong
dependence on a drug.
- No:27 - additional
- existing or coming by way of addition; added, further.
- No:28 - additive
1. characterized by addition. 2. a substance, as a flavouring
agent, preservative, or vitamin, added to another substance to
improve its appearance, increase its nutritional value, etc.
- No:29 - adenitis
inflammation of a gland.
- No:30 - adenoma
(adeno- + -oma) a benign epithelial tumour in which the cells form
recognizable glandular structures or in which the cells are clearly
derived from glandular epithelium.
- No:31 - adequate
satisfactory in quantity or quality; sufficient.
- No:32 - adhesion
(L. adhaesio, from adhaerere to stick to) 1. the property of
remaining in close proximity, as that resulting from the physical
attraction of molecules to a substance, or the molecular attraction
existing between the surfaces of contacting bodies. 2. the stable
joining of parts to each other, which may occur abnormally. 3. a
fibrous band or structure by which parts abnormally adhere.
- No:33 - adjuvant
(L. adjuvans aiding) a substance which aids another, such as an
auxiliary remedy; in immunology, nonspecific stimulator (e.g., BCG
vaccine) of the immune response.
- No:34 - adnexitis
inflammation of the adnexa uteri.
- No:35 - adolescent
an individual during the period of adolescence.
- No:36 - adrenergic
activated by, characteristic of, or secreting epinephrine or
substances with similar activity; the term is applied to those
nerve fibres that liberate norepinephrine at a synapse when a nerve
impulse passes, i.e., the sympathetic fibres.
- No:37 - adrenolytic
(adreno + Gr. lysis a loosening) inhibiting the action of
adrenergic nerves; inhibiting the response to epinephrine.
- No:38 - adsorption
(L. ad to + sorbere to suck) the attachment of one substance to the
surface of another; the concentration of a gas or a substance in
solution in a liquid on a surface in contact with the gas or
liquid, resulting in a relatively high concentration of the gas or
solution at the surface. Cf. absorption.
- No:39 - adult
(L. adultus grown up) a living organism which has attained full
growth or maturity.
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