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G M Christman J F Randolph R P Kelch J C Marshall 《The Journal of clinical endocrinology and metabolism》1991,72(6):1278-1285
Polycystic ovarian disease (PCO) is characterized by hyperandrogenism, ovulatory dysfunction, and altered gonadotropin secretion. Mean plasma FSH concentrations are low, while LH is elevated in a majority of patients. LH pulsatile secretion has been shown to occur at rapid follicular phase frequencies (approximately one pulse per h) in PCO, suggesting persistent rapid frequency GnRH secretion in this disorder. Anovulatory women with PCO were given estradiol (E2; Estraderm skin patches) and progesterone (P; vaginal suppositories) to produce midluteal concentrations for 21 days. The aim was to determine if E2 and P would slow LH (GnRH) pulse frequency and if this would result in augmented FSH secretion and follicular development after withdrawal of E2 and P. Plasma LH was measured every 10 min for 8 h before, during (days 10 and 20), and 7 days after withdrawal of E2 and P (day 28). On each of these study days FSH was measured hourly, and E2 and P were measured every 2 h. After sampling, GnRH (25 and 250 ng/kg, iv) was given to assess pituitary responsiveness. Follicular development was monitored by vaginal ultrasound through day 34 of the study. Basal LH frequency was 8.5 +/- 0.5 pulses/8 h (mean +/- SEM). During E2 and P, LH pulse frequency fell to 3.3 +/- 1.0 (10 days) and 2.3 +/- 0.8 (20 days), 39% and 27% of the basal value, respectively, and subsequently increased to 5.6 +/- 0.7 (66% of basal) 7 days after withdrawal of E2 and P. LH pulse amplitude (basal, 7.2 +/- 1.5 IU/L) was not reduced until day 20, but remained suppressed (3.9 +/- 1.1 IU/L) on day 28. As a result, mean LH (basal, 21.0 +/- 3.5 IU/L) fell progressively during E2 and P, to 3.8 +/- 1.2 IU/L on day 20, and remained low (39% of basal) 7 days after steroid withdrawal. Mean plasma FSH (basal, 7.1 +/- 0.9 IU/L) also fell during steroid administration, but in contrast to LH, had risen to 93% of the basal value by 7 days after E2 and P. LH release in response to exogenous GnRH revealed marked initial responses which did not decrease until day 20, but remained suppressed (8% of basal) after withdrawal of E2 and P. FSH responses were also suppressed on day 20, but had increased to 75% of the basal value by day 28. Initiation of follicular development occurred in all patients, and the lead follicle measured 12.3 +/- 0.8 mm 13 days post-E2 and P. Ovulation occurred in one patient.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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L Christman 《American journal of psychotherapy》1987,41(3):384-390
Up to now not many patients have interacted with trained psychiatric nurses, since their numbers have been small. It is only a recent development that nurses are continuing their education to the Master's and Ph.D. levels. Suggestions for courses are made. Because of the growing convergence of the biological and behavioral sciences, nurses will be in a strong position to provide effective patient management. Their traditional involvement in the community, the work place, the schools, as well as the fact that they are in close contact with medical and surgical patients in particular stressful situations, may enable them not only to treat but even mitigate emergent psychopathology. Nurses would be uniquely placed to interact with other members of the mental health professions and to supplement their work. 相似文献
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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
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Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献
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