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991.
This article estimates the population prevalence of current injection drug users (IDUs) in 96 large US metropolitan areas to facilitate structural analyses of its predictors and sequelae and assesses the extent to which drug abuse treatment and human immunodeficiency virus (HIV) counseling and testing are made available to drug injectors in each metropolitan area. We estimated the total number of current IDUs in the United States and then allocated the large metropolitan area total among large metropolitan areas using four different multiplier methods. Mean values were used as best estimates, and their validity and limitations were assessed. Prevalence of drug injectors per 10,000 population varied from 19 to 173 (median 60; interquartile range 42–87). Proportions of drug injectors in treatment varied from 1.0% to 39.3% (median 8.6%); and the ratio of HIV counseling and testing events to the estimated number of IDUs varied from 0.013 to 0.285 (median 0.082). Despite limitations in the accuracy of these estimates, they can be used for structural analyses of the correlates and predictors of the population density of drug injectors in metropolitan areas and for assessing the extent of service delivery to drug injectors. Although service provision levels varied considerably, few if any metropolitan areas seemed to be providing adequate levels of services.  相似文献   
992.
Capacity and competence in the field of child and adolescent psychiatry are complex issues, because of the many different influences that are involved in how children and adolescents make treatment decisions within the setting of mental health. This article will examine some of the influences which must be considered, namely: developmental aspects, the paradoxical relationship between the need for autonomy and participation and the capacity of children, family psychiatry, and the duty of care towards children and adolescents. The legal frameworks relevant to consideration of consent and competence will be briefly considered, as well as some studies of children's consent, participation and competence. A case vignette will be used as a focus to consider the complexity of the issue of competence in child and adolescent psychiatry, in the particular mental disorder of anorexia nervosa.  相似文献   
993.
994.
The discriminatory effects of categorizing psychiatric patients into competent and incompetent, have urged lawyers, philosophers and health care professionals to seek a functional approach to capacity assessment. Dutch and English law have produced some guidelines concerning this issue. So far, most legal systems under investigation have concentrated on alternatives for informed consent by the patient in case of mental incapacity, notably substitute decision-making, intervention of a judge and advance directives. It is hard to judge the way in which the law may further adapt to a more functional assessment of capacity, because the nature of law shows that legal reforms usually take place only when new methods have been accepted by the field. This is not yet the case today.  相似文献   
995.
996.
997.
目的了解乌鲁木齐市维吾尔族婴儿母乳喂养状况。方法采用队列研究的方法,对362例新生儿的母亲进行了为期6个月的随访调查。结果产妇出院时婴儿的纯母乳喂养率为15.5%。几乎纯母乳喂养率为70.4%,80%母乳喂养率为6.1%,50%母乳喂养率为1.4%,20%母乳喂养率为1.7%,人工喂养率为5.0%。在随访的母乳喂养婴儿中,0.5个月、1.5个月、2.5个月、3.5个月、4.5个月和6个月的纯母乳喂养率分别为9.9%、17.8%、1.5%、0.4%、0%、0%;几乎纯母乳喂养率分别为81%、72.2%、76.7%、47.1%、1.7%、3.3%;80%母乳喂养率分别为6.7%、4.8%、9.1%、23.8%、41.3%、1.4%;50%母乳喂养率分别为0%、0.9%、7.3%、11.2%、17.0%、5.1%;20%母乳喂养率分别为1.5%、1.5%、1.8%、13.9%、35.2%、59.1%;人工喂养率分别为0.9%、2.7%、3.6%、3.6%、4.8%、31.2%:考虑到产妇出院时的人工喂养率,上述各月份的人工喂养率分别为5.9%、7.7%、8.6%、8.6%、9.8%、36.2%。结论纯母乳喂养率较低,应该加强母乳喂养重要性的宣传,尽可能使婴儿母乳喂养时间延长到6个月。  相似文献   
998.
BACKGROUND/PURPOSE: This study was designed to investigate the effects of 6 months of nocturnal nasal positive pressure ventilation (NNPPV) on respiratory muscle function and exercise capacity in patients with chronic respiratory failure. METHODS: A prospective, randomized, controlled design was used. Twenty-nine patients with chronic respiratory failure were enrolled and allocated to either the NNPPV (n = 14) or control group (n = 15). Patients in the NNPPV group received bi-level positive pressure ventilation via nasal mask for 6 consecutive months. Arterial blood gas, respiratory muscle assessment and 6-minute walk test (6MWT) were performed before and after the 6-month NNPPV intervention. Respiratory muscle function was assessed using the variables of maximal inspiratory pressure (Pimax), maximal expiratory pressure (Pemax), and maximum voluntary ventilation (MVV). RESULTS: Subjects in the NNPPV group showed a significant improvement in blood gas exchange and increased 6-minute walk distance (6MWD) compared to baseline and the control group. The 6MWD was significantly increased from 257.1 +/- 114.1 to 345.2 +/- 109.9 m (34.3%) in the NNPPV group. NNPPV also significantly improved MVV and Pimax relative to baseline. MVV was significantly increased from 19.2 +/- 6.5 to 22.3 +/- 7.1 L/min (16.1%) in the NNPPV group (p < 0.05). Furthermore, there was a significant correlation between the magnitude of MVV improvement and 6MWD change. CONCLUSION: The 6-month NNPPV treatment significantly decreased the partial pressure of carbon dioxide and improved daytime respiratory muscle function, thus contributing to exercise-capacity increase in patients with chronic respiratory failure.  相似文献   
999.
OBJECTIVE: To determine whether endoscopic retrograde cholangiopancreatography (ERCP) and common bile duct (CBD) stone extraction should be performed routinely before surgery or'selectively after surgery in patients with mild to moderate gallstone pancreatitis. SUMMARY BACKGROUND DATA: The role and timing of ERCP in mild to moderate gallstone pancreatitis remains controversial. Routine preoperative ERCP identifies persisting CBD stones but carries risks of complications and may delay definitive care. Selective postoperative ERCP, performed only if a CBD stone is seen on intraoperative cholangiography (IOC), avoids unnecessary ERCP but risks unsuccessful stone extraction. METHODS: A prospective, randomized study of consecutive patients with gallstone pancreatitis was conducted. Using previously determined criteria, patients with acute cholangitis or necrotizing pancreatitis were excluded. Patients considered at high risk for persisting CBD stones (CBD size > or =8 mm on admission ultrasound, serum total bilirubin > or = 1.7 mg/dL, or serum amylase > or = 150 U/L on hospital day 4) were randomly assigned to routine preoperative ERCP followed by laparoscopic cholecystectomy, or laparoscopic cholecystectomy with selective postoperative ERCP and endoscopic sphincterotomy only if a CBD stone was present on IOC. Primary end points were costs, length of hospital stay, and the combined treatment failure rates (failure of diagnostic ERCP and IOC, complications of ERCP and endoscopic sphincterotomy, and complications of surgery). RESULTS: One hundred fifty-four consecutive patients with gallstone pancreatitis were evaluated prospectively for study eligibility. Sixty patients met the randomization criteria. Thirty patients were randomized to routine preoperative ERCP and 29 patients to selective postoperative ERCP (1 patient refused). Age, admission laboratory values, and APACHE II and Imrie scores were similar in both groups. By protocol, ERCP was performed in all patients in the preoperative ERCP group. In the postoperative ERCP group, ERCP was necessary in only 7 of 29 patients (24%). Mean hospital stay was significantly longer in the routine preoperative ERCP group (11.7 days) than in the selective postoperative ERCP group (9.0 days). Mean total cost was higher in the preoperative ERCP group ($9,426) than in the postoperative ERCP group ($7,798). The combined treatment failure rate was 10% in both groups. CONCLUSIONS: In patients with mild to moderate gallstone pancreatitis without cholangitis, selective postoperative ERCP and CBD stone extraction is associated with a shorter hospital stay, less cost, no increase in combined treatment failure rate, and significant reduction in ERCP use compared with routine preoperative ERCP.  相似文献   
1000.
Fan ST  Lo CM  Liu CL 《Annals of surgery》2000,231(1):126-131
OBJECTIVE: To report the authors' experience with living donor liver transplantation in adults using right lobe liver grafts, performed by a modified technique. SUMMARY BACKGROUND DATA: The initial results of seven living donor liver transplants in adults using extended right lobe grafts were satisfactory, but serious complications occurred in two donors, and six recipients required repeat laparotomy. Another 11 similar operations were performed. Further evaluation was made with the aim of improving the postoperative outcome. METHODS: From December 1996 to August 1998, 11 patients underwent living donor liver transplantation using right lobe grafts. The first four patients underwent surgery using methods previously designed and the next seven underwent a modification designed to minimize devitalized tissues on the liver transection surface, improve hepatic venous drainage, and reduce the number of hepatic duct orifices. RESULTS: There were no donor deaths. Donor complications included cholestasis (n = 1) and minor wound infection (n = 1). All the first four recipients required a repeat laparotomy for infected necrotic liver transection surface (n = 1), acute pancreatitis (n = 1), hepatic vein thrombosis (n = 1), and leakage from one of the two bilioenteric anastomoses (n = 1). The patient with hepatic vein thrombosis died. In the last seven recipients, all of whom survived the operation, one required a repeat laparotomy with the discovery of a methicillin-resistant Staphylococcus aureus culture of fibrinous exudate at the left subphrenic peritoneum, and another had right hepatic duct stump necrosis. The latter was likely related to hypovolemic shock secondary to bleeding from the right saphenous vein on removal of a hemofiltration catheter. Comparison of the incidence of repeat laparotomy between the first four and the remaining seven recipients showed a significant trend of improvement. Combining the result of the seven patients reported previously, the improvement in terms of relaparotomy rate is significant. CONCLUSION: With modification of surgical technique, living donor liver transplantation in adults using right lobe liver grafts can become a relatively safe procedure.  相似文献   
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