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121.
AIM: Uterine transplantation is developing into a clinical treatment for uterine factor infertility. An animal model with a similar uterus size and vessels to humans and with pregnancy extending over several months would be beneficial for research on uterine transplantation. The aim of this study was to develop and evaluate autotransplantation of the sheep uterus to an orthotopic position in the pelvis. METHODS: Female sheep (n=7) were subjected to laparotomy with the uterus and its vascular supply and drainage being surgically isolated. The excised uterus was kept ex vivo at +4 degrees C for 60 min and then autotransplanted with vascular end-to-side anastomoses to the external iliac vessels. The effects of uterine blood-reperfusion were assessed by measurements of pCO(2), pO(2), lactate and pH in uterine venous blood. Uterine contractility and histology was assessed after 3 h of reperfusion. RESULTS: Reperfusion of blood was observed in five out of seven transplanted uteri. The pCO(2)/pO(2)-ratio and the lactate level were initially elevated but decreased and became normal after 60 min. After 3 h of reperfusion there was a visible tissue blood flow and spontaneous uterine contractions were seen. Histological analysis revealed a mild inflammation, but no edema or stasis. CONCLUSIONS: This study demonstrates that the sheep uterus can successfully be autotransplanted to an orthotopic position with novel vascular connections. This model is suitable for future experiments studying long-term results concerning uterine viability and pregnancy using a transplanted uterus of similar size to the human uterus.  相似文献   
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Several 1-(hydroxy/substituted phenyl)propenones were tested as molluscicidal agents among which the 1-(2-hydroxy/substituted phenyl)-3-(2-furyl)propenones 1a - c show the most promising results. In an attempt to improve their activity, new dihydropyrazolo[1,5-c][1,3]benzoxazines, their thio and their dehydrogenated derivatives were prepared. The pyrazolo[1,5-c][1,3]benzoxazines 4a , b were hydrolyzed affording the 3-(2-furyl)-5-(2-hydroxy/substituted phenyl) pyrazoles 8a , b . The hydroxyimino derivatives 10a - c were synthesized together with their corresponding isoxazole derivatives 11a - c . - Molluscicidal assay indicated that the oximes 10b , c . the isoxazole 11b , the pyrazole 8b , and its N-carbamoyl derivative 9b are most effective. They have in common the conjugated system shown in Fig. 1 which is presumably the active core.  相似文献   
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Recent reports have indicated the presence of transmissible spongiform encephalopathy or Creutzfeldt-Jakob disease in the United States. This disease can occur as a rare, sporadic disease with no recognizable pattern of transmission or as a familial disease associated with prion protein gene mutations. This article discusses the presence of sporadic Creutzfeldt-Jakob disease in a woman who became pregnant early in the course of the disease and subsequent care pre- and postdelivery.  相似文献   
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Background: The current prospective study investigated the hypothesis of metal fume fever (MFF) being a predictor for the development of respiratory symptoms and functional abnormalities. Methods: The study consisted of a pre-exposure and two follow up assessments of 286 welding apprentices during an average period of 15 months. A respiratory and a systemic symptom questionnaire, skin prick tests to common allergens and metal salts, spirometry, and methacholine challenge tests were administered. Results: Developing at least one positive skin prick test to a metallic salt solution was found in 11.8% of apprentices. Possible MFF (at least one of fever, feelings of flu, general malaise, chills, dry cough, metallic taste, or shortness of breath) was reported by 39.2% of apprentices. The presence of at least one welding related respiratory symptom (cough, wheezing, or chest tightness) suggestive of welding related asthma was reported by 13.8%. MFF was significantly associated with these respiratory symptoms (OR = 4.92, 95% CI 2.10 to 11.52), after adjusting for age, atopy, smoking, physician diagnosed asthma, and symptoms of non-welding related asthma. Apprentices with possible MFF, and no welding related respiratory symptoms suggestive of welding related asthma at the first follow up, had an increased risk of developing the latter symptoms by the second follow up visit (OR = 7.4, 95% CI 1.97 to 27.45) compared with those not having MFF. MFF was not significantly associated with an increase in bronchial responsiveness. Conclusion: MFF could be a predictor for the development of respiratory symptoms but not for functional abnormalities in welders.  相似文献   
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Aims: To explore associations between work status and multidimensional health indices in a sample of urban Lebanese children.  相似文献   
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HYPOTHESIS: At mass contraction of the descending colon, the colonic contents stop at the sigmoid colon (SC) and do not pass directly to the rectum. We investigated the hypothesis that a continent mechanism seems to exist at the rectosigmoidal junction (RSJ), preventing the direct passage of stools from the descending colon to the rectum. METHODS: The SC in 16 healthy volunteers (mean +/- SD age, 38.6 +/- 10.2 years; 9 men and 7 women) was distended with an isotonic sodium chloride solution-filled balloon, and the pressure response of the RSJ and the rectum was recorded at rapid and gradual filling of the balloon. The test was repeated after the SC and RSJ were anesthetized separately. RESULTS: Rapid SC balloon distension with a mean +/- SD of 52.1 +/- 3.6 mL of isotonic sodium chloride solution effected an RSJ pressure increase to a mean +/- SD of 67.8 +/- 18.4 cm H(2)O (P<.01) with no rectal pressure response (P>.05). Slow SC filling produced a progressive increase in RSJ pressure but no rectal pressure change. At a mean +/- SD SC distending volume of 86.3 +/- 4.1 mL, the RSJ pressure decreased to 9.6 +/- 2.8 (P<.01), and the balloon was dispelled to the rectum; rectal pressure increased (P<.001), and the balloon was expelled to the exterior. The RSJ pressure did not respond to distension of the anesthetized SC. CONCLUSIONS: Contraction of the RSJ at rapid SC distension with big volumes implies a reflex relationship that we call the RSJ guarding reflex. This reflex seems to prevent the descending colon contents from passing directly to the rectum. It is considered the first continent reflex and may serve as an investigative tool in the study of fecal incontinence.  相似文献   
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