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BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献   
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Antigen detection techniques are available for the identification of bacterial polysaccharides, viruses, and chlamydia. Viruses and chlamydia are detected by direct immunofluorescence (DFA) or enzyme immunoassay (EIA). Bacterial polysaccharides are detected by latex agglutination or staphylococcal coagglutination of serum or concentrated urine. Most studies have not compared these techniques to the gold standard of lung puncture, so the role of dual infections with bacteria and viruses cannot be adequately determined. The sensitivity of any of these techniques is dependent on the quality of the antisera used. Monoclonal sera are now available for the detection of most viruses and seem to be as sensitive as polyclonal sera. DFA or EIA may offer equal sensitivity but their advantages and disadvantages must be considered by the local diagnostic laboratories. Most DFA and EIA systems have a sensitivity of 90% when compared with viral cultural for the identification of the organism. Agglutination reagents are available commercially for the detection of pneumococcal and Hemophilus influenzae type b polysaccharides. The sensitivity and specificity of each brand should be determined on serum or urine from patients known to have positive blood cultures and those free of disease. The brand chosen should be the one that has reasonable sensitivity and specificity. Rapid diagnostic techniques are helpful if they are used within a clinical context and they are positive. Negative tests do not rule out infection.  相似文献   
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The Low Vision Clinic at the Palmerston North Hospital has now been oerating for 70 years. Over the course of these ten years a number of factors have emerged which can be as readily applied to general ophthalmological practice as to low vision practice. The philosophy of low vision care is one of which all ophthalmologists should be aware and includes factors to be taken into account when dealing with children, people in the workplace, and everyday factors involved in daily living activities, all of which are equally relevant in routine ophthalmological practice. This paper endeavours to share some thoughts on these factors and also discusses means by which the visually handicapped can be helped in areas where specialist low vision services are not readily available.  相似文献   
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A. S. C. Rice  MB  BS  Registrar  F. Reynolds  MD  FFARCS 《Anaesthesia》1987,42(12):1320-1323
Forty women who underwent gynaecological surgery were randomly allocated to receive trichloroethylene, enflurane, or enflurane plus fentanyl as adjuncts to nitrous oxide/relaxant anaesthesia with controlled ventilation. No serious cardiac dysrhythmias were seen in any group. Each patient was observed postoperatively for 4 hours by a nurse blind to the technique used, and questioned at 24 hours by a similarly blinded anaesthetist. Recovery after trichloroethylene was not significantly prolonged although postoperative analgesia by visual analogue was better, opiate analgesia was required less frequently and there was less nausea and vomiting than in either of the enflurane groups. We argue for the continued use of trichloroethylene by this technique, because it costs one hundred times less than enflurane and because of the potential morbidity of the postoperative opiate dosage required after enflurane.  相似文献   
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OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems. (Am J Obstet Gynecol 1998;178:1222-8.)  相似文献   
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