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51.
OBJECTIVES: To study reproductive pattern and perinatal mortality in rural Tamil Nadu, South India. DESIGN: Community based, cross sectional questionnaire study of 30 randomly selected areas served by health subcentres. SETTING: Rural parts of Salem District, Tamil Nadu, South India. SUBJECTS: 1321 women and their offspring delivered in the 6 months before the interview. MAIN OUTCOME MEASURES: Number of pregnancies, pregnancy outcome, spacing of pregnancies, sex of offspring, perinatal and neonatal mortality rates. RESULTS: 41% of the women (535) were primiparous; 7 women (0.5%) were grand multiparous (> 6 births). The women had a mean age of 22 years and a mean of 2.3 pregnancies and 1.8 live children. The sex ratio at birth of the index children was 107 boys per 100 girls. The stillbirth rate was 13.5/1000 births, the neonatal mortality rate was 35.3/1000, and the perinatal mortality rate was 42.0/1000. Girls had an excess neonatal mortality (rate ratio 3.42%; 95% confidence interval 1.68 to 6.98; this was most pronounced among girls born to multiparous women with no living sons (rate ratio 15.48 (2.04 to 177.73) v 1.87 (0.63 to 5.58) in multiparous women with at least one son alive). CONCLUSIONS: In this rural part of Tamil Nadu, women had a controlled reproductive pattern. The excess neonatal mortality among girls constitutes about one third of the perinatal mortality rate. It seems to be linked to a preference for sons and should therefore be addressed through a holistic societal approach rather than through specific healthcare measures.  相似文献   
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Although self-report data are generally evaluated as reliable, validity estimates for self-reported drinking behavior are not as favorable. A new method of measurement addressing problems currently associated with the questionable validity of self-report drinking information is introduced. Study 1 tests the correspondence between the new measure (occasions per year blood alcohol level exceeded 0.08%), traditional self-report measures, and laboratory alcohol consumption. The novel measure correlated most strongly with volume of alcohol consumed in the laboratory compared to the traditional measures. In Study 2 the novel measure was favored over a traditional measure when discriminating between the presence and absence of problem-drinking symptoms.  相似文献   
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Pancreatic cancer is an aggressive disease with a dismal prognosis. It has long been regarded as one of the most difficult cancers to accurately diagnose and stage preoperatively. The purpose of this review is to provide an update of the state-of-the-art for early detection, diagnosis, and staging of pancreatic cancer. These methods include spiral CT scans, magnetic resonance imaging, positron emission tomography (PET) imaging, laparoscopy, endoscopic ultrasound, CA 19-9 serology, fine needle aspiration cytology, ERCP brush cytology, and screening for p53 and ras oncogenes. These advanced techniques should help us to detect pancreatic cancers in high-risk populations at a curative stage and to decrease pancreaticoduodenectomies for benign disease which could otherwise be treated with less morbid procedures. In addition, these tests will help reliably diagnose pancreatic cancer preoperatively.  相似文献   
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OBJECTIVE: To describe the occurrence of endometriosis in monozygotic twins. DESIGN: Postal questionnaire plus confirmation of disease status. SETTING: Twins were recruited via the American Endometriosis Association and the National Endometriosis Society of Great Britain and via British gynecologists. RESULT(S): Fourteen twin pairs were concordant for endometriosis, and two were discordant. Nine pairs of twins had moderate-severe endometriosis. CONCLUSION(S): These findings contribute to the growing body of literature that suggests endometriosis has a genetic basis.  相似文献   
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Primary mouse epidermal cells underwent spontaneous malignant transformation in culture. TWelve malignant epidermal cell lines were established which produced squamous cell carcinomas in syngeneic hosts. These lines were used to define criteria for recognizing transformed epidermal cells in vitro. Growth in suspension in agar, agarose, or Methocel was minimal for 11 of the lines. All lines tested retained specific epidermal antigens (pemphigus, pemphigoid, keratin) by indirect immunofluorescence, but keratin content was reduced when quantified by radioimmunoassay. Basal activity of ornithine decarboxylase and activity induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate were variable among lines. All malignant lines as well as normal epidermal cells grew well at reduced extracellular calcium concentrations. When the extracellular calcium was elevated, normal cells ceased proliferation, terminally differentiated, and sloughed from the culture dish, while malignant cells continued to proliferate although they expressed differentiative functions. These results indicate that malignant transformation in epidermis is associated with a fundamental alteration in the program of terminal differentiation which allows some cells to escape the proliferative block and cell death which accompanies differentiation in normal keratinocytes. This alteration should be useful to select for transformants during the process of carcinogenesis in vitro.  相似文献   
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