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281.
A double-blind trial with clonidine and a placebo to treat hot flushes   总被引:2,自引:0,他引:2  
A double-blind crossover study that compared clonidine and a placebo, which were administered to 19 postmenopausal women who were suffering from hot flushes, failed to demonstrate any statistical reduction in the number of hot flushes. Therefore, clonidine is not recommended as a treatment drug for this symptom.  相似文献   
282.
Previous studies suggest species differences in the central neural effects of gold thioglucose (GTG). To further assess these differences, we studied the effects of single intraperitoneal injections of GTG on the brains of golden hamsters (Mesocricetus auratus). Within 48 hr of treatment, each of the GTG doses tested (500, 1000 and 1500 mg/kg) had produced lesions in the ventromedial hypothalamus and area postrema. These findings are of interest since they identify the hamster as the first animal known to be susceptible to GTG-induced lesion formation, but resistant to the hyperphagia commonly associated with glucose analog glucoprivation.  相似文献   
283.
Over a 10-year period, 65 of 196 patients (33%) with ovarian epithelial malignancy, previously treated with chemotherapy, had a second-look operation if the disease was clinically absent. All procedures were done by one of three gynecologic oncologists, and 48% of the patients had a positive second-look procedure. Of patients with original stage I, II disease, 25% had a positive second-look operation, contrasting with 61% of patients with stage III, IV. Significant perioperative morbidity occurred: one patient had intraoperative vascular collapse; 15% had prolonged ileus; 17% had small bowel resections at the time of the second-look operation or in the postoperative period. Of all patients with negative second-look operations, 24% have had recurrent disease from 5 to 23 months after the procedure. These recurrences were in the liver or distant sites in 63% of the patients. Second-look operations, if still indicated by negative noninvasive techniques, should be performed in tertiary care centers under study situations in a standard fashion.  相似文献   
284.
In acute quadriplegia we have noted that about one in five patients develops unexplained production of markedly excessive and tenacious bronchial mucus. Spontaneous recovery from mucus hypersecretion usually occurs within weeks to months. Mucus samples collected from 12 patients have been found to be abnormal. Macromolecular contents of single aspirates yielded as much as 500 mg. Analytical ultracentrifuge analysis showed the mucus to contain considerable epithelial glycoprotein (GP) of typical buoyant density; its amino acid and carbohydrate compositions were characteristic of the GP from hypersecretory bronchial mucus such as in chronic bronchitis and cystic fibrosis. In five patients studied after recovery from hypersecretion, there tended to be relatively less GP. The mucus samples contained a high density glycoconjugate (GC): this had sugars of GP but also reacted positively with a monoclonal antibody to keratan sulfate. Its amino acid composition was different from that of GP: threonine was lower and glycine was higher than in GP. In mucus from one patient who died, chondroitin sulfate ABC and hyaluronic acid were identified as well. This suggests proteoglycans are involved in the pathophysiology of mucus hypersecretion. The sudden onset and spontaneous recovery of hypersecretion suggests that it is not due to gland hypertrophy. We speculate that in acute quadriplegia it is due to disturbed neuronal control of bronchial mucus gland secretion, perhaps related to initial disappearance and later reappearance of peripheral sympathetic nervous system tone.  相似文献   
285.
286.
Archives of Sexual Behavior - Over a 6-year period, 106 women involved with men who cross-dress (mostly heterosexual transvestites) completed a questionnaire regarding themselves, their male...  相似文献   
287.
Cross-sectional analysis of four general representative populations of middle-aged adults in the United States in 1986-1989 provides estimates of the close relation of high density lipoprotein cholesterol (HDL cholesterol) to its major structural apolipoprotein (apolipoprotein A-I) and to fasting plasma triglyceride levels. HDL cholesterol differences of approximately 0.4 mg were associated with 1-mg differences in apolipoprotein A-I; differences of 20% in HDL cholesterol (reductions) were associated with triglyceride doublings. Variation in apolipoprotein A-I and triglyceride concentration together accounted for 66% of the population variance in HDL cholesterol. The uniformity of this pattern in the four race-sex groups studied suggests an important role of triglyceride-cholesterol transfer as a determinant of HDL cholesterol. The fundamental relations observed among HDL cholesterol, apolipoprotein A-I, and triglycerides were unaltered by levels of factors under personal volition. The volitional factors appeared to influence HDL cholesterol indirectly: Obesity and physical activity were affected primarily through their associations with triglycerides, and alcohol use and smoking through associations with apolipoprotein A-I. The association of alcohol use with elevated HDL cholesterol was attenuated in persons with greater body mass.  相似文献   
288.
In 82 patients who underwent gastroduodenoscopy, acute and chronic gastric mucosal inflammation was scored for severity, and systemic humoral immune responses to Helicobacter pylori antigens were assessed by enzyme-linked immunosorbent assays. On the basis of culture, gastric histology, and serologic evaluation, 33 patients were classified as H. pylori infected and 36 were classified as uninfected. Thirteen patients had negative cultures and stains but were seropositive and were analyzed separately from the other two groups. Specific serum immunoglobulin G (IgG) subclass responses to H. pylori whole-cell antigens and specific IgG responses to the 54-kDa heat shock protein homolog (Hp54K) and vacuolating cytotoxin were significantly greater in infected than in uninfected patients as were specific IgA responses to whole-cell antigens and cytotoxin (P < 0.001). Among the H. pylori-infected persons, serum IgG responses to Hp54K and to the vacuolating cytotoxin were correlated with acute mucosal inflammatory scores. In contrast, serum IgA responses to whole-cell sonicate and to vacuolating cytotoxin were inversely related to chronic inflammatory scores. By multivariant regression analysis, only specific serum IgG responses to Hp54K correlated with severity of inflammation (both acute and chronic; P < 0.001); these responses may be markers of inflammation or these antibodies could play a direct role in the pathogenesis of H. pylori-induced inflammation.  相似文献   
289.
Many concerns surround the preparation of a person with spina bifida for a successful transition into adult life and responsibilities. A model of intervention must be based on developmental concerns and timely issues from infancy through all stages of development to young-adult life. This article discusses, within a developmental framework, issues of transition in relation to physical, social, emotional, and educational/vocational needs; it also presents a conceptual framework for the transition into adulthood. Guidelines were developed by incorporating expected outcomes of people with spina bifida and using a philosophical framework that encompasses the achievement of a balance among dependence, independence, and interdependence. This model is based on developmental issues from infancy through all stages of development to young-adult life. Using this framework for care, the rehabilitation nurse can feel confident that the needs of clients with spina bifida and similar chronic conditions are being met.  相似文献   
290.
Assembly of synthetic cellulose I.   总被引:2,自引:0,他引:2       下载免费PDF全文
Cellulose microfibrils with an electron diffraction pattern characteristic of crystalline native cellulose I have been assembled abiotically by means of a cellulase-catalyzed polymerization of beta-cellobiosyl fluoride substrate monomer in acetonitrile/acetate buffer. Substantial purification of the Trichoderma viride cellulase enzyme was found to be essential for the formation of the synthetic cellulose I allomorph. Assembly of synthetic cellulose I appears to be a result of a micellar aggregation of the partially purified enzyme and the substrate in an organic/aqueous solvent system favoring the alignment of glucan chains with the same polarity and extended chain conformation, resulting in crystallization to form the metastable cellulose I allomorph.  相似文献   
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