Biomedical subjects

S J Cook

Publications and source records attributed to S J Cook.

75 records · Page 5Linked to original sources

PubMed1982

Quantitation of six androgens by combined high performance liquid chromatography and radioimmunoassay.

A technique was developed to separate six androgens (testosterone, dihydrotestosterone, androstenedione, 5 alpha-androstane-3 alpha, 17 beta-diol, 5 alpha-androstane-3 beta, 17 beta-diol, and androsterone) by high performance liquid chromatography prior to quantitation by specific radioimmunoassay systems. Methanol:water (60:40 v:v) was used as the solvent system with a C18 reversed-phase column. The method was verified and used to quantitate the androgens in serum from adult rams bled every 20 minutes for 6 hours and yearling bulls bled every 30 minutes for 8 hours. Concentrations of all 6 androgens varied in an episodic manner with testosterone being the dominant androgen.

Androgens↗

PubMed1980

Plasma C19-delta 5-steroid levels during normal human pregnancy.

Plasma levels of dehydroepiandrosterone sulfate, dehydroepiandrosterone and delta 5-androstenediol were measured in several women throughout pregnancy. The levels of both dehydroepiandrosterone and its sulfate decreased while those of delta 5-androstenediol did not. The levels of binding of the latter steroid to plasma proteins increased.

Adult↗

PubMed1972

New deoxyribonucleic acid polymerase induced by Bacillus subtilis bacteriophage PBS2.

The deoxyribonucleic acid (DNA) of Bacillus subtilis phage PBS2 has been confirmed to contain uracil instead of thymine. PBS2 phage infection of wild-type cells or DNA polymerase-deficient cells results in an increase in the specific activity of DNA polymerase. This induction of DNA polymerase activity is prevented by actinomycin D and chloramphenicol. In contrast to the major B. subtilis DNA polymerase, which prefers deoxythymidine triphosphate (dTTP) to deoxyuridine triphosphate (dUTP), the DNA polymerase in crude extracts of PBS2-infected cells is equally active whether dTTP or dUTP is employed. This phage-induced polymerase may be responsible for the synthesis of uracil-containing DNA during PBS2 phage infection.

Bacillus subtilis↗