| a1PI | Symbol for human alpha 1-proteinase inhibitor. (05 Mar 2000) |
|---|---|
| A2 thalassaemia | Beta thalassaemia, heterozygous state. (05 Mar 2000) |
| a2-neuraminoglycoprotein | A glycoprotein that contains neuraminic acid and which during electrophoresis migrates with the a2 portion of serum proteins. See: C1 esterase inhibitor. (05 Mar 2000) |
| AA | <biochemistry> A class of organic molecules that containing an amino group and can combine in linear arrays to form proteins in living organisms. There are twenty common amino acids: alanine, arginine, aspargine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine. They are key components in all living things from which proteins are synthesised by formation of peptide bonds during ribosomal translation of messenger RNA. All the amino acids have the L configuration, except glycine which is not optically active. Other amino acids occurring in proteins, such as hydroxyproline in collagen, are formed by post translational enzymatic modification of amino acid residues in polypeptide chains. There are also several important amino acids, such as the neurotransmitter y aminobutyric acid, that have no relation to proteins. Amino acids can now be produced by biotechnology in bulk using fermentation and biotransformation. Acronym: AA (13 Nov 1997) |
| aaa disease | Endemic anaemia of ancient Egypt, ascribed in the Papyrus Ebers to intestinal infestation with ancylostoma; now called ancylostomiasis. (05 Mar 2000) |
| Aad | <abbreviation> Alpha-aminoadipic acid. (05 Mar 2000) |
| AAF | <abbreviation> 2-acetylaminofluorene; 2-acetamidofluorene. (05 Mar 2000) |
| AAMC | <abbreviation> Association of American Medical Colleges. (05 Mar 2000) |
| AAR | <abbreviation> Antigen-antibody reaction. (05 Mar 2000) |
| aardvark | <zoology> An edentate mammal, of the genus Orycteropus, somewhat resembling a pig, common in some parts of Southern Africa. It burrows in the ground, and feeds entirely on ants, which it catches with its long, slimy tongue. Origin: D, earth-pig. Source: Websters Dictionary (01 Mar 1998) |
| aardwolf | <zoology> A carnivorous quadruped (Proteles Lalandii), of South Africa, resembling the fox and hyena. See Proteles. Origin: D, earth-wolf. Source: Websters Dictionary (01 Mar 1998) |
| Aaron's rod | 1. A rod with one serpent twined around it, thus differing from the caduceus of Mercury, which has two. 2. <botany> A plant with a tall flowering stem; especially. The great mullein, or hag-taper, and the golden-rod. (19 Mar 1998) |
| Aaron's sign | <clinical sign> In acute appendicitis, a referred pain or feeling of distress in the epigastrium or precordial region on continuous firm pressure over McBurney's point. (05 Mar 2000) |
| Aaron, Charles | U.S. Physician, 1866-1951. See: Aaron's sign. (05 Mar 2000) |
| Aarskog syndrome | <syndrome> Grier et al. (1983) reported father and 2 sons with typical Aarskog syndrome, including short stature, hypertelorism, and shawl scrotum. They tabulated the findings in 82 previous cases. X-linked recessive inheritance has been repeatedly suggested. The family reported by Welch (1974) had affected males in 3 consecutive generations. Thus, there is either genetic heterogeneity or this is an autosomal dominant with strong sex-influence and possibly ascertainment bias resulting from use of the shawl scrotum as a main criterion. Stretchable skin was present in the cases of Grier et al. (1983). Teebi et al. (1993) reported the case of an affected mother and 4 sons (including a pair of monozygotic twins) by 2 different husbands. They suggested that the manifestations were as severe in the mother as in the sons and that this suggested autosomal dominant inheritance. Actually, the mother seemed less severely affected, compatible with X-linked inheritance. Clinical signs: Mild to moderate short stature,normocephaly, Widow's peak hair, maxillary hypoplasia, broad nasal bridge, anteverted nostrils, long philtrum, broad upper lip, curved linear dimple below the lower lip, hypertelorism, ptosis, down-slanted palpebral fissures, ophthalmoplegia, strabismus, hyperopic astigmatism, large cornea, floppy ears, lop-ears,cleft lip/palate, shawl scrotum, saddle-bag scrotum, cryptorchidism, brachydactyly, digital contractures, clinodactyly, mild syndactyly, transverse palmar crease, lymphoedema of the feet, ligamentous laxity, osteochondritis dissecans, proximal finger joint hyperextensibility, flexed distal finger joints, genu recurvatum, flat feet, stretchable skin, cervical spine hypermobility, odontoid anomaly, macrocytic anaemia, hemochromatosis, hepatomegaly, portal cirrhosis, imperforate anus, rectoperineal fistula, interstitial pulmonary disease, sternal deformity. Inheritance: Sex-influenced autosomal dominant form, also X-linked form. (05 Aug 1998) |