A

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A

 

A

 
absorbance, activity (radioactivity), area, mass number.

ā

 (L.)
an´te (before).

α

 
alpha, the first letter of the Greek alphabet, often used to indicate the first member of a series, such as the α chain of hemoglobin. See also terms beginning alpha.

A

1. Abbreviation for ampere; adenine; alanine; alanyl.
2. As a subscript, refers to alveolar gas.
3. Symbol (usually capitalized italic, A) for absorbance.
4. Symbol for adenosine or adenylic acid in polynucleotides; alanine or alanyl in polypeptides.
5. First substrate in a multisubstrate enzyme-catalyzed reaction.

A


a

1. Abbreviation for total acidity; ante; area; asymmetric; auris; artery; arteria [TA].
2. Symbol for atto-.
3. As a subscript, refers to systemic arterial blood.

a

A

abbr.
1. adenine
2. ampere
3. or Å angstrom
4. area

a

Abbreviation for:
absorptivity
acceleration
chemical activity
arterial blood gas
atto-

A

Abbreviation for:
abnormal
absorbance
accessory
acetum
actin
Actinomyces
adenine
adenosine
admittance Electricity
adrenaline
adriamycin
agar
akinetic
alanine
albino guinea pig
alcohol
allele
allergist
allergy
alternating current
alveolar gas
ampere
amphetamine
anaphylaxis
Angstrom
animal
anion
annealing
anterior
antigen
antinuclear antibody (ANA is more commonly used)
aqueous
area
arterial
arteriolar
asbestos
asparagine
atrial
atrium
assist
atropine
auricular
auris (ear)
axis
a regional street term for LSD ONDCP
mass number
radioactivity

A

Symbol for:
1. Actin.
2. Adenine.
3. Adrenaline.
4. Adriamycin.
5. Alanine.
6. Ampere.
7. Amphetamine.
8. Anaphylaxis.
9. Angstrom.
10. Anion.
11. Anterior.
12. Aqueous.
13. Area.
14. Asparagine.
15. Atrium.
16. Auricular.
17. Axis.

a

Symbol for:
1. Absorptivity.
2. Acceleration.
3. Chemical activity.
4. Arterial blood gas.
5. atto-.

°A

Abbreviation for degree absolute; replaced by K (kelvin).

A

Abbreviation for alveolar ventilation

A

Abbreviation for absolute; adenine; alanine; ampere.

A

Abbreviation for Helmholtz energy.

a

Abbreviation for absorptivity.

a

Abbreviation for specific absorption coefficient.

A

abbrev.
  1. ABSORBANCE.
  2. the nitrogenous base ADENINE in NUCLEIC ACIDS.
  3. ALANINE.
  4. ANGSTROM.

Å

abbrev. ANGSTROM.

A

Abbreviation for alanine; ampere.

Ā

Abbreviation for anion.
References in periodicals archive ?
(1995) determined that the structures of both PbTx-1 and PbTx-2 are relatively linear with a bend approximately mid-molecule, possess a lactone functionality in the A-ring, have a strictly rigid region in the terminal four rings, possess a side chain allowing modest modification at the molecules' termini, and have a spacer region that separates the rigid region from the A-ring lactone.
(1995) described a brevetoxin PbTx-2 molecule believed to be composed of three distinct segments: a relatively rigid fourring H-K ring system, an A-ring lactone, and a B-G ring region with limited flexibility.
The B-G ring system is a spacer region that separates binding from an activity locus, the A-ring. The intact A-ring lactone modulates both inactivation activity and mean open time in single-channel patch-clamp experiments (Jeglitsch et al.
(a) Toxin Shift Subconductance Longer mean modification activation states (b) open time Natural toxins Yes Yes (1) Yes Modified A-ring Yes No No Open A-ring Yes Yes (4) Yes Short spacer region Yes No No Bulky side chain Yes No No Saturated H-ring No (c) No No Brevenal ND ND ND Toxin Inhibit Toxin modification inactivation antagonist Natural toxins Yes No Modified A-ring Yes No Open A-ring Yes No Short spacer region No No Bulky side chain No Yes Saturated H-ring No No Brevenal ND Yes ND, not determined.
The relationship of brevetoxins "length" and A-ring functionality to binding and activity in neuronal sodium channels.
Likewise, for 17[beta]-estradiol (Figure 2), the 3-OH group of the A-ring and the C17[beta] hydroxylic oxygen of the D-ring both act as anchoring elements and H-bond donors within ER[alpha] (Brzozowski et al.
1996) that the carbonyl oxygen of the A-ring and the C17[beta] hydroxylic oxygen of the D-ring in DHT most likely interact through H-bonds with [Arg.sup.752] in helix 5 and [Thr.sup.877] in helix 11 in AR-LBD, respectively, because mutation of these residues caused a complete androgen-insensitivity syndrome (Sultan et al.
In common with other known AR antagonists, fenitrothion and its organophosphorus-like AR antagonist analogues all contain the essential A-ring phenyl feature with a putative strong H-bond interaction site.
These compounds did not, however, provide a good candidate feature for D-ring H-bond interaction according to the "near-10 [Angstrom] polar interactions rule" (the thiol was computed to be a 7.5 [Angstrom] separation from the A-ring H-bond acceptor site), which is consistent with lack of reported agonist properties.
The importance of essential structural elements in the central binding region is also supported by the observed 15-fold increase in binding affinity for fenitrothion versus methylparathion upon A-ring substitution of a hydrogen for a methyl at the R3 A-ring position (see Table 1).