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21.
A successful feature of the 4th-year curriculum in the Medical Faculty of the Queen's University, Belfast has been the development of interdisciplinary teaching in a three-week joint course to which several clinical departments contribute...Co-ordinated teaching of topics of common interest in small groups included, until the academic year 1987/88, a three-hour session on medical ethics. In the spring of 1987 the authors approached the Department of Philosophy at Queen's; subsequently proposals for a formal multidiscipinary course in medical ethics for 4th-year clinical students in the Medical Faculty, for the academic year 1987/88, were approved by the Education Committee of the Medical Faculty. 相似文献
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Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318
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Staphylococcal exopolysaccharides inhibit lymphocyte proliferative responses by activation of monocyte prostaglandin production. 下载免费PDF全文
The glycocalyx (exopolysaccharides) of Staphylococcus epidermidis has been reported to inhibit a variety of host defense mechanisms. We have examined the inhibitory effects of glycocalyx on the proliferation of human peripheral blood mononuclear cells (PBMC) and the mechanism of this inhibition. Glycocalyx isolated and partially purified under endotoxin-free conditions from defined liquid medium cultures of S. epidermidis and Staphylococcus lugdunensis inhibited the proliferative response of PBMC when added to cultures at 10 to 100 micrograms/ml. Glycocalyx-mediated inhibition of phytohemagglutinin-stimulated proliferation of PBMC required the presence of plastic-adherent peripheral blood monocytes. Culture supernatants of monocytes stimulated with glycocalyx contained a soluble factor that inhibited the proliferation of monocyte-depleted PBMC. This soluble inhibitory factor was not produced in the absence of glycocalyx or in the presence of both glycocalyx and indomethacin. Analysis of the supernatants of cultures of adherent monocytes revealed that glycocalyx from S. epidermidis and from S. lugdunensis could activate monocyte production of prostaglandin E2 (PGE2), human interleukin-1, and tumor necrosis factor alpha. The addition of purified PGE2, at the same levels of PGE2 (greater than or equal to 10(-9) M) generated in the monocyte cultures, to PBMC cultures resulted in a similar inhibition of proliferative responses. It is concluded that, contrary to previous suggestions, the bacterial glycocalyx does not have a direct inhibitory effect on T lymphocytes. However, it does appear that glycocalyx from coagulase-negative staphylococci can activate monocyte PGE2 production and that it is this activity that in turn contributes to the inhibition of T-cell proliferation. 相似文献
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Zelinski-Wooten MB; Slayden OD; Chwalisz K; Hess DL; Brenner RM; Stouffer RL 《Human reproduction (Oxford, England)》1998,13(2):259-267
Large doses of antiprogestin typically disrupt menstrual cyclicity. A
chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which
permits continued menstrual cyclicity but alters gonadal- reproductive
tract activity, was established. Rhesus monkeys received vehicle (n = 6) or
0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight
daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and
gonadotrophin profiles were normal during cycles involving vehicle and 0.01
and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle
oestradiol and gonadotrophin surges, and subsequent progesterone
production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied
by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half
the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group
were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of
C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and
cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily
treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in
macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed
ovarian cyclicity, menstruation was disrupted in some animals. Increasing
the dose to 0.1 mg/kg antagonized pituitary function and resulted in
anovulation and amenorrhoea. A chronic low-dose regimen of the
antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity,
has potential as a contraceptive in women.
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