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41.
Previously, we reported that short term administration of a highly potent GnRH agonist (GnRHa) for 1 month to patients with polycystic ovarian disease (PCO) resulted in complete suppression of ovarian steroidogenesis without measurable effects on adrenal steroid production. This new study was designed to evaluate the effects of long term GnRHa administration in PCO patients with respect to their hormone secretion patterns and clinical responses. Eight PCO patients and 10 ovulatory women with endometriosis were treated daily with sc injections of [D-His6-(imBzl]),Pro9-NEt]GnRH (GnRHa; 100 micrograms) for 6 months. Their results were compared to hormone values in 8 women who had undergone bilateral oophorectomies. In response to GnRHa, PCO and ovulatory women had rises of serum LH at 1 month, after which it gradually declined to baseline. In both groups FSH secretion was suppressed throughout treatment. Serum estradiol, estrone, progesterone, 17-hydroxyprogesterone, androstenedione, and testosterone levels markedly decreased to values found in oophorectomized women by 1 month and remained low thereafter. In contrast, serum pregnenolone and 17-hydroxypregnenolone were partially suppressed, and dehydroepiandrosterone, dehydroepiandrosterone sulfate, and cortisol levels did not change. Clinically, hyperplastic endometrial histology in three PCO patients reverted to an inactive pattern, and proliferative endometrium in two other PCO patients became inactive in one and did not change in the other. Regression of proliferative endometrial histology occurred in all ovulatory women. Vaginal bleeding occurred in all women studied during the first month of GnRHa administration, after which all but one PCO patient became amenorrheic. Hot flashes were noted by all ovulatory women and by four of eight PCO patients. All PCO patients noted subjective reduction of skin oiliness, and five had decreased hair growth. We conclude that in premenopausal women: 1) chronic GnRHa administration results in apparently complete persistent suppression of ovarian steroid secretion; 2) adrenal steroid secretion is not influenced directly or indirectly; and 3) its use may be helpful in the treatment of endometrial hyperplasia and ovarian androgen excess in women with PCO.  相似文献   
42.
Although the revision rates for modern knee prostheses have decreased drastically, the total number of revisions a year is increasing because many more primary knee replacements are being done. At the time of revision, bone loss is common, which compromises prosthetic stability. To improve stability, intramedullary stems are often used. The aim of this study was to estimate the effects of a stem, its diameter and the interface bonding conditions on patterns of the bone remodeling in the distal femur.

We created finite element models of the distal half of a femur in which 4 types of knee prostheses were placed. The bone remodeling process was simulated using a strain-adaptive bone remodeling theory. The amount of such remodeling was determined by calculating the changes in bone mineral density in 9 regions of interest from simulated DEXA scans.

The computer simulation model showed that revision prostheses tend to cause more bone resorption than primary ones, especially in the most distal regions. Predicted long-term bone loss due to a revision prosthesis with a thin stem equalled that around a prosthesis with an intercondylar box. However, strong regional differences were found- the stemmed prostheses having more bone loss in the most distal areas and some bone gain in the more proximal ones. A prosthesis with a thick stem led to an increase in bone loss. When the prosthesis-cement interface was bonded, more bone loss was predicted than with an unbonded interface. These results suggest that a stem which increases stability initially may reduce stability in the long term. This is due to an increase in stress shielding and bone resorption.  相似文献   
43.
Evidence indicates that endogenous opioid peptides and glucocorticoids participate in the control of cardiovascular regulation during hemorrhagic shock. In the present study, we investigated a possible interaction between brain opioid peptides and adrenal corticosteroids regarding the control of arterial pressure during hemorrhage. The bleeding volumes required to lower arterial pressure to 80, 60 and 40 mmHg were studied in anesthetized sham-operated (SHAM) and adrenalectomized (ADX) rats. I.c.v. administration of 10 micrograms of naloxone resulted in a significant increase in the bleeding volume required to lower arterial pressure from 60 to 40 mmHg in SHAM animals, whereas no effect of naloxone was observed in ADX animals. Replacement therapy with a 100% corticosterone pellet (100 mg, s.c.), but not with a 12.5% corticosterone pellet (12.5 mg corticosterone and 87.5 mg cholesterol, s.c.), resulted in an effect of naloxone on the bleeding volume in ADX animals. The effect of replacement therapy could be inhibited by i.c.v. pretreatment with the synthetic glucocorticoid receptor antagonist, RU38486 (100 ng). These data suggest that (1) opioid mechanisms are involved in the regulation of blood pressure during hemorrhage, and (2) occupancy of glucocorticoid receptors is required for naloxone to exert its hemodynamic effect during hemorrhagic hypotension in ADX rats.  相似文献   
44.
Rat brain hippocampal slices were incubated with or without the convulsant 4-aminopyridine (4-AP). From these slices a crude mitochondrial/synaptosomal membrane fraction was prepared and analyzed for endogenous protein phosphorylation. 4-AP (10(-5) M) stimulated the phosphorylation of a 50 kDa protein by 86%. The phosphorylation of this 50 kDa protein is Ca2+/calmodulin-dependent and we suggest that this protein is the lower molecular weight subunit of Ca2+/calmodulin-dependent protein kinase II (CaMK II).  相似文献   
45.
A longitudinal survey (February 1984 - January 1985) on the incidence of acute diarrhea episodes in a sample of 8,164 children (aged 0–12 years) living in southeastern Sicily was carried out by means of weekly telephone interviews with doctors practising in the territory. The incidence rate was 0.479 (0.472–0.485 95% C.I.) per child per year and the frequency of episodes was significantly higher (p < 0.001) in children aged 0–4 years (0.86). Diarrhea was more frequent in industrial areas than in rural ones, and almost half (45.1%) of the total episodes had a mild course. No death from diarrhea occurred and admission to hospital was reported for 8.4% of all cases.Corresponding author.  相似文献   
46.
目的:探讨周围血管损伤自全大隐静脉移植治疗的方法。适应证和治疗效果。方法:回顾性分析22例周围血管损伤自体大隐静脉移植治疗的临床资料,并阐述了术中注意事项,提出最佳手术时机及预后情况。结果:22例均采用自体大隐静脉移植,痊愈19例(86.4%)。截肢3例(13.6%),22例患者无死亡,随访2-9年,20例肢体功能恢复满意,2例移植段狭窄,但肢体功能良好。结论:自体大隐静脉移植是治疗周围血管损伤行之有效的方法之一。血管吻合的时间应在24h以内,最佳为8h以内。  相似文献   
47.
Female rats consistently show a pattern of differences in defensive behaviors compared to males which parallel the effects of exposure to a nonpainful threat stimulus (cat or cat odor) in the same tests and measures. These indications of greater defensiveness for females are particularly common in situations involving potential, as opposed to actual and present, threat, a factor which probably also reflects ceiling or floor effects in situations involving very intense defensiveness. In addition, pharmacological studies indicate sex differences in the effects of selective serotonin (5-HT) receptor agonists and antagonists on defensive responding. These findings indicate that sex effects must be considered in studies of the pharmacological control of defensive behaviors, and suggest that responsivity to sex effects may be an additional criterion for the suitability of animal models of anxiety.  相似文献   
48.
Is interleukin 2 a neuromodulator in the brain?   总被引:5,自引:0,他引:5  
A bidirectional flow of information exists between the CNS and the neuroendocrine and immune systems, representing an important homeostatic mechanism in the body. Lymphokines and other products of immunocompetent cells seem to play a crucial role in this communication and seem to exert powerful effects on neurones in the brain. In this article, Giuseppe Nisticò and Giovambattista De Sarro describe the central effects following interleukin 2 (IL-2) microinfusion into several areas of the rat brain. The locus coeruleus seems to be the main site in the brain through which IL-2 exerts soporific effects. In addition, the possible transducing mechanisms coupling IL-2 receptor stimulation and the electroencephalogram (EEG) spectrum power responses elicited from the locus coeruleus seem to involve stimulation of specific receptors coupled to adenylate cyclase through a Gi protein.  相似文献   
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