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排序方式: 共有1982条查询结果,搜索用时 15 毫秒
81.
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83.
The changes in unconjugated estradiol-17beta and estriol, progesterone and chorionic somatomammotropin (HCS) in peripheral plasma have been studied in 18 women at 30-minute intervals following intra-uterine prostaglandin E2 administration for therapeutic termination of second trimester pregnancy. The hormonal changes were related to the time of fetal death detected by the disappearance of fetal heart pulsations. Prostaglandin E2 was given by the intra-amniotic route with urea (5 patients) or with intravenous oxytocin (5 patients), or by the extra-amniotic route with intravenous oxytocin (8 patients). Fetal death occurred rapidly with intra-amniotic PGE2, but usually at a late stage with extra-amniotic PGE2. Three fetuses in the extra-amniotic group died at or just before abortion. A variety of fetal heart changes were noted and the time of fetal death did not appear to influence the time of abortion within each treatment subgroup. Estradiol and estriol showed a sligh but persistent fall over 24 hours prior to induction of abortion. A more rapid fall usually occurred after induction, with a consistent fall around the time of fetal death. Progesterone and HCS usually fell much less before and immediately after fetal death. A marked rise in estradiol sometimes occurred before fetal death, particularly in the intraamniotic PGE2 and urea subgroup. Estriol levels declined more rapidly before than after fetal death, whereas fetal death had less consistent effects on the other hormones. All hormones had usually fallen considerably at the time of abortion, and in some individuals marked fluctuations in hormone levels were seen. 相似文献
84.
KM Mattila C Forsell T Pirttil? JO Rinne T Lehtim?ki M R?ytt? L Lilius A Eerola PH St George-Hyslop H Frey L Lannfelt 《Canadian Metallurgical Quarterly》1998,44(6):965-967
In early-onset familial Alzheimer's disease (AD) pathogenic mutations have been found in the amyloid precursor protein (APP) gene and in the presenilin (PS)-1 and PS-2 genes. We screened for mutations in these genes in 20 patients with familial AD from the Finnish population. In addition, we sampled 41 sporadic AD patients and 59 controls to test for mutations identified in our familial AD cases. We detected an A-to-G transition in the PS-1 gene, resulting in a glutamic acid (Glu)-to-glycine (Gly) substitution at codon 318 in 2 familial and 2 sporadic AD patients. The Glu318Gly mutation has previously been reported to cause AD. We also found the Glu318Gly mutation in 4 healthy aged controls (range, 74-87 years). We thus conclude that the mutation is most likely a rare polymorphism not related to AD. 相似文献
85.
Testosterone and the testosterone precursors pregnenolone, progesterone, 17 alpha-hydroxyprogesterone, 17 alpha-hydroxypregnenolone, androstenedione, androstenediol and dehydroepiandrosterone were measured in the spermatic vein plasma and in the testicular tissue of young and old men. Testosterone and its precursors decreased in the testicular tissue of old men. However, progesterone and 17 alpha-hydroxyprogesterone increased in relation to testosterone in the testicular tissue and in the spermatic vein of old men. It is assumed that these age-dependent changes are caused by an impaired oxygen supply of the ageing testes. This hypothesis is supported by the observation that the same changes in steroid pattern seen in old age can be observed under reduced oxygen supply in in vitro incubation experiments with testicular tissue. 相似文献
86.
KM Moritz A Butkus AC McFarlane A Albiston R Salenmi EM Wintour 《Canadian Metallurgical Quarterly》1998,24(3-4):937-941
By mid-gestation (75-85 days, term=150 days), the ovine fetal adrenal gland is zoned into cortex and medulla. The cortex has an outer layer of cells which have the morphological characteristics of zona glomerulosa cells, containing mitochondria with lamellar cristae. It has been reported that cultured adrenal cells from mid-gestation bovine and ovine fetuses can be stimulated to increase aldosterone production, ten fold, by angiotensin II, and that this can be maintained for at least 3 days. However, the situation in vivo is unknown. In the current report we show that in chronically cannulated ovine fetuses at mid-gestation, angiotensin II (1 microg/h) does not increase aldosterone either in the short term (3 hours) or long term (3 days). However, ACTH (450 ng/h) can increase plasma aldosterone in the short but not long term. ACTH at this dose produces progressive and large increases in cortisol production. Angiotensin II is pressor and produces a modest diuresis without stimulating cortisol. 相似文献
87.
DB Veprintsev SE Permyakov EA Permyakov VV Rogov KM Cawthern LJ Berliner 《Canadian Metallurgical Quarterly》1997,412(3):625-628
The thermal denaturation of bovine and human apo-alpha-lactalbumins at neutral pH has been studied by intrinsic protein fluorescence, circular dichroism (CD), and differential scanning microcalorimetry (DSC) methods. Apo-alpha-lactalbumin possesses a thermal transition with a midpoint about 25-30 degrees C under these conditions (pH 8.1, 10 mM borate, 1 mM EGTA), which is reflected in changes in both fluorescence emission maximum and quantum yield. However, the CD showed a decrease in ellipticity at 270 nm with a midpoint at about 10-15 degrees C, while DSC shows the transition within the region of 15-20 degrees C. The non-coincidence of transition monitored by different methods suggests the existence of an intermediate state in the course of the thermal denaturation process. This intermediate state is not the classical molten globule state which occurs at higher temperature (i.e. denatured state at these conditions) [D.A. Dolgikh, R.I. Gilmanshin, E.V. Brazhnikov, V.E. Bychkova, G.V. Semisotnov, S.Y. Venyaminov and O.B. Ptitsyn, FEBS Letters, 136 (1981) 311-315] and has physical properties intermediate between the native and molten globule states. 相似文献
88.
Our laboratory has shown that tumor necrosis factor-alpha (TNF alpha) can regulate normal mammary epithelial cell (MEC) growth, morphogenesis, and, under certain circumstances, functional differentiation in a manner similar to epidermal growth factor (EGF). As TNF alpha has been shown to up-regulate EGF receptor (EGFR) expression and function in other systems, the present studies were undertaken to determine whether TNF alpha action in MEC was indirect through stimulation of the EGFR. An inhibitor of EGFR tyrosine kinase activity, PD158780, failed to block proliferation induced by 40 ng/ml TNF alpha and only partially inhibited growth in response to 2 ng/ml TNF alpha. PD158780 was also unable to suppress the extensive morphological development induced by either TNF alpha concentration. In contrast, the effects of TNF alpha and PD158780 on functional differentiation (i.e. casein accumulation) were time dependent. When measured on day 7 after 48 h of treatment, casein accumulation was unaffected by either concentration of TNF alpha or by PD158780. When assessed on day 21 after 16 days of treatment, however, casein levels were decreased by 40 ng/ml TNF alpha and increased by PD158780. Significantly, this PD158780-induced increase in casein was not observed in MEC that had been treated with both PD158780 and TNF alpha. These results thus suggest that EGFR tyrosine kinase activity is not necessary for TNF alpha action in normal MEC. 相似文献
89.
90.
KM Koslowski PR Shaver JT Casey T Wilson G Yamanaka AK Sheaffer DJ Tenney NE Pederson 《Canadian Metallurgical Quarterly》1999,73(2):1704-1707
Herpes simplex virus (HSV) DNA is cleaved from concatemers and packaged into capsids in infected cell nuclei. This process requires seven viral proteins, including UL15 and UL28. UL15 expressed alone displays a nuclear localization, while UL28 remains cytoplasmic. Coexpression with UL15 enables UL28 to enter nuclei, suggesting an interaction between the two proteins. Additionally, UL28 copurified with UL15 from HSV-infected cells after ion-exchange and DNA affinity chromatography, and the complex sedimented as a 1:1 heterodimer upon sucrose gradient centrifugation. These findings are evidence of a physical interaction of UL15 and UL28 and a functional role for UL15 in directing UL28 to the nucleus. 相似文献