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1.
Twenty-eight patients underwent surgery for intractable pain, duodenal or extrahepatic biliary obstruction secondary to chronic pancreatitis. Eleven had pancreatic duct obstruction alone, six biliary obstruction alone, seven combined pancreatic and biliary, two combined biliary and duodenal, one combined pancreatic and duodenal, and one simultaneous pancreatic, biliary, and duodenal obstruction. Pancreatitis was secondary to alcohol in all but one case. The following operations were performed: longitudinal pancreatojejunostomy (20), choledochoduodenostomy (8), choledochojejunostomy (7), cholecystojejunostomy (1), and gastrojejunostomy (4). Of the 20 patients with pancreatic duct drainage, pain relief was complete in 11 and partial in six. Initial incomplete relief of pain, or recurrence, stimulated further diagnostic procedures, leading to improvement or correction of the problem in five patients. A significant (p less than 0.01) fall in alkaline phosphatase (935 +/- 228 to 219 +/- 61 U/L) occurred following surgery. One patient was subsequently found to have pancreatic carcinoma. Two patients were lost to follow-up and four patients died (one perioperative and three late). In conclusion, the possibility of pancreatic, biliary, and duodenal obstruction must be considered in symptomatic patients with chronic pancreatitis. Surgery must be individualized. Drainage procedures, either alone or in combination, are associated with a low morbidity and improved clinical condition and may be preferable to resection in the surgical management of these patients.  相似文献   
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Topical, intravaginal microbicides and spermicides are greatly needed to prevent transmission of sexually transmitted diseases and/or unwanted pregnancies. The development of such compounds is a high research priority. The presumed method of action of existing, or novel, microbicides/spermicides is to provide a chemical barrier to the vaginal epithelium preventing exposure to micro-organisms. Other intravaginal products are used to treat vaginal bacteria of fungal infections. Little is known, however, about the actual or optimal initial distribution and subsequent spread of medications placed in the vagina. We describe a sensitive new technique to quantify the spread of a gel placed in the vagina using magnetic resonance imaging (MRI). Five millilitres of an over-the-counter spermicide containing Nonoxynol-9 was mixed with Gadolinium. MRI was used to quantify spread of the mixture 10 min after insertion with a standard applicator. We demonstrated contiguous spread of gel throughout the vagina. The coverage of material was thicker in the upper vagina than in the lower vagina. We also demonstrated, for the first time, that spermicidal compounds may migrate from the vaginal canal into the endocervix within 10 min of insertion. This finding suggests that topical microbicides/spermicides may act both in the vaginal canal and in the upper female genital tract.  相似文献   
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BACKGROUND: A 1999 study in Hanoi, Vietnam using the International Study on Asthma and Allergies in Childhood (ISAAC) questionnaire showed a high prevalence of atopic symptoms. Identifying risk factors for symptoms in these children may help in understanding the causes for these high estimates. METHODS: An ISAAC questionnaire with supplemental questions on environmental variables was distributed to 5495 school children in Hanoi and a suburban district, Dong Anh. The response rate was 65.7%. RESULTS: In Dong Anh, the following were among the significant age and gender adjusted associations: pig ownership [odds ratio (OR) (95% confidence interval), OR = 1.79 (1.18-2.70) for doctor-diagnosed asthma (DDA), OR = 1.72 (1.08-2.78) for doctor diagnosed hay fever (DDHF)] and farming [OR = 1.67 (1.27-2.19) for ever asthma, OR = 1.51 (1.09-2.09) for DDHF]. In multivariate models, tuberculosis (TB) was a significant predictor of atopic symptoms [Hanoi: OR = 3.09 (1.10-8.70) for DDA, Dong Anh: OR = 3.71 (1.40-9.84) for DDA, OR = 4.66 (1.88-11.57) for DDHF]. CONCLUSIONS: These findings are contrary to the "hygiene hypothesis". Recent immunologic and epidemiologic studies refute the inverse association between allergy and TB and may be one explanation for the positive association in this study. The positive association with pig ownership and farming may be because of exposures on farms in a developing country that may be different from exposures in farms of developed countries.  相似文献   
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Although firefighters have been shown in some studies to suffer chronic respiratory morbidity from their occupational exposures, an increased risk for dying from non-malignant respiratory diseases has not been documented in any previous retrospective cohort mortality study. In order to assess the possibility that an unusually strong "healthy worker effect" among firefighters might mask this increased risk, a mortality analysis of firefighters was carried out in three cities in relation to the United States population and also to a comparison cohort of police officers. The firefighters were employed between 1945 and 1980 and experienced 886 deaths by 1 January 1984; compared with the United States population they had a significantly reduced risk of dying from all causes (SMR = 82, 95% confidence interval, 77-87), and from non-malignant circulatory diseases (SMR = 81, 95% confidence interval 73-89), but no significant difference in risk of non-malignant respiratory diseases (SMR = 88, 95% confidence interval 66-117). Compared with police, the firefighters experienced a trend toward improved mortality outcomes for all causes investigated (SMR = 82), but they had an excess of deaths from non-malignant respiratory diseases (SMR = 141). The results indicate that firefighters are probably at increased risk for dying from non-malignant respiratory diseases; this increased risk may have been missed in previous studies because of the limitations of using a general reference population.  相似文献   
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Actual or perceived exposure to hazardous materials may result in physiologic and psychological effects. However, hyperventilation following such exposures has not previously been reported. After a large-scale industrial release of oxides of nitrogen, five (29%) of 17 patients evaluated at a major trauma center were hyperventilating, as defined by arterial PCO2 <33 mm Hg, and nine patients (53%) had arterial PCO2 <37 mm Hg. First responders (rescue team members and paramedics) had a higher rate of hyperventilation than other occupational groups. Age, gender, marital status, decontamination, and mode of arrival were not significantly associated with hyperventilation, although marital status approached significance. This study suggests that hyperventilation may be a common reaction after hazardous-materials incidents, and that certain populations may be at increased risk for this condition.  相似文献   
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Multivariate random length data occur when we observe multiple measurements of a quantitative variable and the variable number of these measurements is also an observed outcome for each experimental unit. For example, for a patient with coronary artery disease, we may observe a number of lesions in that patient's coronary arteries, along with percentage of blockage of each lesion. Barnhart and Sampson first proposed the multiple population model to analyse multivariate random length data without covariates. This paper extends their approach to deal with multiple covariates. We propose a new multiple population regression model with covariates, and discuss the estimation issues. We analyse data from the TYPE II coronary intervention study to illustrate the methodology.  相似文献   
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As we move into the 1990s, the challenges we face are many. Our ever-changing health care industry is giving managers, directors, and administrators much to ponder: how do we reduce costs and improve patient care? One promising area that may help answer this question in pharmacy services is bar code technology. This article offers helpful advice about the development of bar code and drug delivery systems and discusses the future applications of bar code technology in pharmacy practice, based on 3 years of hands-on experience at Florida Medical Center.  相似文献   
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Neonatal mice 1 and 5 days of age and older mice 25 days of age were injected with an increasing dose of monosodium glutamate (MSG) for a ten-day period and observed for at least 150 days. Both male and female animals in the 1- and 5-day age group treated with MSG showed large increases in weight over controls along with a shortened body length. The MSG group also showed decreases in locomotor and explatory behavior. The 25-day animals took much longer to show effects or failed to show any effects, indicating that the MSG-induced changes studied are age dependent. Possible methodological considerations accounting for conflicting reports in the MSG literature are discussed in light of the present findings.  相似文献   
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