Biomedical subjects

P Hsieh

Publications and source records attributed to P Hsieh.

56 records · Page 4Linked to original sources

PubMed1975

Altered blood androgens in elderly men with prostate hyperplasia.

Plasma testosterone (T) and dihydrotestosterone (DHT) were measured in the plasma of otherwise healthy men ages 60-90 who had prostate hyperplasia. The androgens were measured by specific radioimmunoassays using paper and celite column chromatography. In the elderly subjects, plasma T was 466+/-35 (SE) ng per 100 ml which is reduced (p less than 0.05) as compared with values from younger men. In contrast, DHT levels were elevated when compared with values from men ages 20-39, 89 (53-152) versus 49 (33-74) 95% confidence ng per 100 ml. Analysis of data by the Mann Whitney U test demonstrates that the groups are different (p less than 0.001). These studies indicate that DHT levels and T/DHT ratios are altered in unstressed elderly men with BPH. Further study is necessary to delineate the source of DHT and whether these altered androgen levels are the cause of prostate hypertrophy or an unrelated effect of aging.

Adult↗

PubMed1973

A rat mammary carcinoma in vivo and in vitro: establishment of clonal lines of the tumor.

Clonal cell lines from a pituitary hormone-dependent rat mammary carcinoma were established. The growth of these cell lines in vitro is markedly stimulated in the presence of prolactin. The cells grow well in a medium supplemented with fetal-calf serum (generation time: 9-10 hr), but do not grow with calf serum. Fetal-calf serum supports little growth when the serum is subjected to anti-prolactin-affinity chromatography. Gel filtration of fetal-calf serum indicates that the growth stimulatory activity is in a large molecular weight material (close to 100,000), suggesting that prolactin is associated with another serum component. A variant of the original tumor, which does not require hormone for growth, was obtained, and clonal cell lines of this tumor were also established. These cells, in contrast to the hormone-dependent ones, grow well with either fetal-calf serum (with or without anti-prolactin treatment) or calf serum.

Animals↗