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KL Gatford TP Fletcher IJ Clarke PC Owens KJ Quinn PE Walton PA Grant BJ Hosking AR Egan EN Ponnampalam 《Canadian Metallurgical Quarterly》1996,74(6):1314-1325
The effects of sex and age on patterns of circulating somatotropin (ST) concentration and plasma IGF-I, IGF-II, insulin, and IGF binding protein-3 (IGFBP-3) were studied in ram, wether, and ewe lambs (n = 7 or 8) sampled at mean ages of 81 (I1) and 158 d (I2). Between 81 and 158 d of age, rams grew more rapidly than wethers (P < .01), and wethers grew more rapidly than ewes (P < .01). The sex differences in growth were reflected in empty body weight at slaughter: rams > wethers > ewes (P < .05). Mean plasma ST concentrations, ST pulse amplitude, and integrated plasma ST concentrations were greater (P < .05) in rams than in ewes at I1 and I2. Characteristics of the ST plasma profile in wethers were generally intermediate between those of rams and ewes. The interpulse interval was greater in ewes than in wethers at I2. The IGF-I and IGFBP-3 concentrations were greater in rams than in ewes at both sampling times. Plasma IGF-II was greater in ewes than in rams at I2. Mean plasma ST was approximately two thirds less at I2 than at I1 regardless of sex. Mean plasma ST and IGF-I at both ages were positively correlated with growth. Mean plasma ST at I2 was negatively correlated with fatness at slaughter. Sex and age significantly affected patterns of circulating ST and concentrations of IGF-I and IGFBP-3 in prepubertal growing lambs, under conditions for which growth rates and composition were also sexually dimorphic. 相似文献
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Hepatic and pancreatic effects of polyenoylphosphatidylcholine in rats with alloxan-induced diabetes
V Buko O Lukivskaya V Nikitin Y Tarasov L Zavodnik A Borodinsky B Gorenshtein B Janz KJ Gundermann R Schumacher 《Canadian Metallurgical Quarterly》1996,14(2):131-137
In neonatally allylestrenol treated animals in adult age a single benzpyrene treatment significantly decreases the female and significantly increases the male rat's sexual activity. Three month old females display the negative sexual behavioral effect of neonatal allylestrenol treatment less than the six month old ones. The benzpyrene treatment in adult age decreases the sexual activity of male rats. The experiments call the attention to the modifying effect of perinatal steroid treatments to similar exposure in adult age. 相似文献
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N Iyer MS Reagan KJ Wu B Canagarajah EC Friedberg 《Canadian Metallurgical Quarterly》1996,35(7):2157-2167
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R Pichlmayr A Weimann J Klempnauer KJ Oldhafer H Maschek G Tusch B Ringe 《Canadian Metallurgical Quarterly》1996,224(5):628-638
OBJECTIVES: The authors evaluated the experience and results of a single center in surgical treatment of proximal bile duct carcinoma. SUMMARY BACKGROUND DATA: Whenever feasible, surgery is the appropriate treatment in proximal bile duct carcinoma. To improve survival rates and with special regard to liver transplantation, the extent of surgical radicalness remains an open issue. PATIENTS AND METHODS: Retrospective analysis of 249 patients who underwent surgery for proximal bile duct carcinoma via the following procedures: resection (n = 125), liver transplantation (n = 25), and exploratory laparotomy (n = 99). Survival rates were calculated according to the Kaplan-Meier method, uni- and multivariate analysis of prognostic factors, and log rank test (p < 0.05). RESULTS: Survival rates after resection and liver transplantation are correlated with international Union Against Cancer (UICC) tumor stage (resection: overall 5-year, 27.1%; stage I and II, 41.9%; stage IV, 20.7%; liver transplantation: overall 5-year, 17.1%; stage I and II, 37.8%; stage IV, 5.8%). Significant univariate prognostic factors for survival after liver resection were lymph node involvement (N category), tumor stage, tumor-free margins, and vascular invasion; for transplantation, they were local tumor extent, N category, tumor stage, and infiltration of liver parenchyma. For resection and transplantation, a multivariate analysis showed prognostic significance of tumor stage and tumor-free margins. CONCLUSION: Resection remains the treatment of choice in proximal bile duct carcinoma. Whenever possible, decisions about resectability should be made during laparotomy. With regard to the observation of long-term survivors, liver transplantation still can be justified in selected patients with stage II carcinoma. It is unknown whether more radical procedures, such as liver transplantation combined with multivisceral resections, will lead to better outcome in advanced stages. With regard to palliation, surgical drainage of the biliary system performed as hepatojejunostomy can be recommended. 相似文献
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MG Beconi-Barker RE Hornish TJ Vidmar KJ Dame SA Brown 《Canadian Metallurgical Quarterly》1996,19(3):192-199
Coccidioides immitis, the primary pathogenic fungus that causes coccidioidomycosis, is most commonly found in the deserts of the southwestern United States and Central and South America. During the early 1990s, the incidence of coccidioidomycosis in California increased dramatically. Even though most infections are subclinical or self-limited, the outbreak is estimated to have cost more than $66 million in direct medical expenses and time lost from work in Kern County, California, alone. In addition to the financial loss, this pathogen causes serious and life-threatening disseminated infections, especially among the immunosuppressed, including AIDS patients. This article discusses factors that may be responsible for the increased incidence of coccidioidomycosis (e.g., climatic and demographic changes and the clinical problems of coccidioidomycosis in the immunocompromised) and new approaches to therapy and prevention. 相似文献
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