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The objective was to determine the effect of hypophysectomy on the store of gonadotropin-releasing hormone (GnRH) in certain parts of the brain as revealed by immunocytochemistry. The antiserum used was prepared against synthetic GnRH conjugated with limpet hemocyanin. No change was observed in the store of GnRH in the organum vasculosum of the lamina terminalis or in the cephalic segment of the median eminence GnRH was depleted severely from the central and caudal (junction with the infundibular stem) segments of the median eminence. GnRH was not found in the axons of magnocellular neurons that regenerate during repair of the median eminence-pituitary stalk after hypophysectomy. 相似文献
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BACKGROUND: Although many studies have examined the effects of antihypertensive agents on proteinuria and glomerular filtration rate in patients with kidney disease, many questions remain unresolved. These questions include whether the effects of agents differ, whether their effects are similar in diabetic and nondiabetic patients with renal disease, and whether the effects of any agents are independent of blood pressure reductions. METHODS: We conducted a meta-analysis of studies obtained with MEDLINE and bibliographies from comprehensive reviews but included only investigations with follow-up times of at least 6 months. We combined data (1) in an analysis of randomized controlled trials, (2) in a separate univariate analysis of controlled and uncontrolled trials, and (3) using weighted multiple linear regression. RESULTS: In 14 randomized controlled trials, angiotensin-converting enzyme inhibitors caused a greater decrease in proteinuria (pooled mean [95% confidence intervals], -0.51[-0.68 to -0.35], ln [treatment/control]), improvement in glomerular filtration rate (0.13 mL/min per month [0.10 to 0.16 mL/min per month]), and decline in mean arterial pressure (-4.0 mm Hg [-4.9 to -3.0 mm Hg]) compared with controls. In a multivariate analysis of controlled and uncontrolled trials, each 10-mm Hg reduction in blood pressure decreased proteinuria (regression coefficient [95% confidence interval] -0.14 [-0.22 to -0.06] ln [after/before]), but angiotensin-converting enzyme inhibitors (-0.45 [-0.58 to -0.32]) and nondihydropyridine calcium antagonists (-0.38 [-0.70 to -0.06]) were associated with additional declines in proteinuria that were independent of blood pressure changes and diabetes. Each 10-mm Hg reduction in blood pressure caused a relative improvement in glomerular filtration rate (0.18 mL/min per month [0.04 to 0.31 mL/min per month]), but among diabetic patients there was a tendency for dihydropyridine calcium antagonists to cause a relative reduction in glomerular filtration rate (-0.68 mL/min per month [-1.31 to -0.04 mL/min per month]). CONCLUSIONS: Long-term beneficial effects of antihypertensive agents on proteinuria and glomerular filtration rate are proportional to blood pressure reductions and are similar in diabetic and nondiabetic patients with renal disease. In addition, angiotensin-converting enzyme inhibitors, and possibly nondihydropyridine calcium antagonists, have additional beneficial effects on proteinuria that are independent of blood pressure reductions. 相似文献
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Four treatment levels (1.0, 2.5, 5.0 and 10.0 x the recommended use level) of a gentian violet premix (Dye-Gen) were compared with non-medicated controls for breeder chickens during a 168-day study. There were no treatment effects up to and including 10 x the recommended use level on: average daily feed consumption, feed/dozen eggs, hatchability of fertile eggs, or mortality. Fertility was higher for the birds receiving 2.5 x the recommended use level than for the non-medicated controls. Egg production was higher (P less than .05) for the non-medicated controls and 10x groups than for the birds receiving the gentian violet premix at 2.5 x the recommended use level. Semen of breeder males was observed for % abnormal sperm, % dead sperm, % motility, vigor, and semen volume. There was no treatment effect on any of the semen characteristics evaluated. It can be concluded from these data that the gentian violet premix is safe for breeder chickens under the conditions of this study. 相似文献
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MT Ashworth BL Pizer A Oakhill RD Spicer PJ Berry 《Canadian Metallurgical Quarterly》1996,16(5):853-859
Tumor markers are used to diagnose certain cancers and can be useful in monitoring the response to treatment. We describe a renal tumor with the features of a teratoid nephroblastoma associated with a raised serum level of alpha-fetoprotein (AFP). The serum AFP remained high during chemotherapy but returned to normal after nephrectomy. AFP was demonstrated by immunohistochemistry in cysts lined by enteric-type epithelium within the tumor. Cytogenetic examination of the tumor showed a clone of cells with trisomy 8. Raised serum AFP has not previously been described in teratoid Wilms' tumor. 相似文献
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BL Blagburn KL Drain TM Land PH Moore RG Kinard DS Lindsay A Kumar J Shi DW Boykin RR Tidwell 《Canadian Metallurgical Quarterly》1998,84(4):851-856
The efficacy of dicationic diarylfurans was evaluated against Cryptosporidium parvum by a suckling murine model. Candidate drugs were solubilized or suspended in deionized water and administered orally at a constant dose rate on days 0-5 (treatment day 0) to suckling ICR Swiss mice experimentally inoculated with oocysts of C. parvum. Efficacy was based on numbers of oocysts recovered from the intestinal tracts of mice subjected to necropsy examination on day 6. Numerous candidate furans significantly reduced the numbers of oocysts recovered from treated mice compared with control mice. Compounds 1, 2, 4, and 9 demonstrated superior efficacies (10% of controls or better) against C. parvum. Compounds 3, 5, 6, 7, 8, 11, 17, 18, and 19 also significantly reduced the numbers of oocysts recovered from treated mice but demonstrated efficacies ranging from 17 to 65% of controls. Compound 4 was particularly efficacious against C. parvum at a dosage as low as 8.5 mg/kg of body weight. Compound 4 is identified as a lead compound for additional studies in other animal models. 相似文献