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71.
PURPOSE: The aim of this study was to assess the efficacy of portoenterostomy in biliary atresia and determine factors that predict outcomes. METHODS: The outcomes after portoenterostomy for biliary atresia from 1976 to 1996 were graded into 3 defined groups: G (good, jaundice free); I (intermediate, progressive liver disease with liver transplant if needed after 3 years of age); P (poor, liver transplant or death at less than 3 years of age). RESULTS: Twenty-seven of 49 children (55%) who underwent portoenterostomy responded. Of these, 13 (26%) were jaundice free (G). Of 14 children (28%) in I, 6 underwent liver transplant after 3 years of age. Of 22 children (44.8%) in P, 14 (28%) died before 3 years and 8 underwent liver transplant before 3 years. Thus, 42% of the children in this series are surviving with native liver. Age at operation in P was significantly different compared with G. Preoperative values of bilirubin and alanine transaminase were comparable in the 3 groups. Postoperative values of bilirubin and alanine transaminase were lower in G and I compared with P Complications were significantly lower in group G. CONCLUSIONS: Portoenterostomy alone in biliary atresia is beneficial in 40% of cases. Factors associated with the outcome include age at operation, postoperative cholangitis, and change in values of bilirubin and alanine transaminase. A classification based on decline of bilirubin and enzyme levels 3 months after portoenterostomy is proposed to predict the long-term outcome of an individual case of biliary atresia. It is particularly relevant in the intermediate group in which timing of referral may preclude or compromise liver transplant.  相似文献   
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OBJECTIVE: This experiment evaluated enterally administered low molecular weight heparin (LMWH) combined with sodium N-[10-(2-hydroxybenzoyl)amino] decanoate (SNAD) for the treatment of induced venous thrombosis. SUMMARY BACKGROUND DATA: SNAD is a delivery agent that potentiates the gastrointestinal absorption of LMWH. METHODS: Forty female pigs were equally assigned to four groups: control (saline); enteral LMWH, 2,000 IU/kg; enteral SNAD, 50 mg/kg; and enteral LMWH, 2,000 IU/kg and SNAD, 50 mg/kg. Under fluoroscopic guidance, the infrarenal vena cava was occluded with a balloon catheter. Two milliliters of ethanol was injected into the distal vena cava. The inflated balloon catheter remained in situ for 5 days, at which time animals angiographically exhibiting thrombus were randomly assigned to the four groups. Study medications were dosed at 12-hour intervals by means of a gastrostomy tube placed previously. After 7 days of treatment, thrombus was extracted. A separate group of 10 animals was used to measure plasma antifactor Xa levels for 6 hours after enteral dosing of LMWH/SNAD. RESULTS: The amount of residual thrombus after treatment with enteral LMWH/SNAD was significantly decreased. Antifactor Xa levels were significantly elevated in the LMWH/SNAD group versus baseline. CONCLUSION: The combination of enterally administered LMWH and SNAD given for 7 days appeared to decrease caval thrombosis in this model of deep vein thrombosis. Enteral LMWH/SNAD effected an increase in plasma levels of antifactor Xa.  相似文献   
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Differences in survival by histologic type of pancreatic cancer.   总被引:3,自引:0,他引:3  
OBJECTIVE: Although pancreatic cancer has an extremely high case fatality rate, little is known about differences in mortality by histologic types. We examined median survival and risk of mortality for endocrine pancreatic tumors and two types of exocrine tumors, adenocarcinomas, and mucinous tumors. METHOD: This analysis included 35,276 pancreatic cancer cases reported to the nine population-based cancer registries participating in the Surveillance, Epidemiology, and End Results program from 1973 to 2000. Survival among cases with pancreatic adenocarcinomas, mucinous tumors, and endocrine tumors were compared using Kaplan-Meier plots. Comparative risks of mortality were evaluated using multivariate adjusted Cox regression models. RESULTS: Endocrine pancreatic cancer cases had a median survival of 27 months compared with a median survival of 4 months for adenocarcinoma and mucinous tumor cases. Compared with adenocarcinoma cases, endocrine tumor cases had a 0.28-fold lower risk of mortality [95% confidence interval (95% CI), 0.26-0.30], and mucinous tumor cases had a 0.88-fold lower risk (95% CI, 0.84-0.91). These results were similar for men and women. Within histologic types, advanced tumor stage, older diagnosis age, surgery, and Black race were associated with increased risks of mortality, whereas female sex and more recent year of diagnosis were associated with decreased risks. CONCLUSION: This study confirms the clinical observation that patients with endocrine pancreatic cancer survive longer than patients with exocrine tumors. A better understanding of these differences could contribute to identifying the underlying causes of pancreatic cancer and to improving survival rates across all histologic types.  相似文献   
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Ethane and pentane are alkanes that are excreted through the lungs to a small degree in healthy subjects. These gasses are produced from the peroxidation of unsaturated fats which are found both in body tissues and in foods. These gasses are excreted in larger amounts by patients with increased production of reactive oxygen metabolites, including those with inflammation or ischemia. Thus, detection of these gasses in excessive quantities is considered evidence for lipid peroxidation. However, the effects of dietary factors on these measurements have not been defined. To define the effects of eating on the pulmonary excretion of these alkanes, 29 healthy subjects were fed a standardized liquid diet (1060 kcal, 12.9 g linoleic acid and 385 mg linolenic acid) after an overnight fast. Breath alkanes were measured at 0, 1, 3, and 6 hours. All subjects had normal vitamin E (1.11 + 0.26 mg/dl), retinol (64 +/? 14 micrograms/dl), beta carotene (27 +/? 21 micrograms/dl), lycopene (23 +/? 12 micrograms/dl) and zinc (81.9 +/? 13.5 micrograms/dl) levels. No statistically significant changes in either alkane were noted relative to the fasting level. We conclude that oral diet does not alter pulmonary ethane or pentane excretion in healthy subjects.  相似文献   
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设计了一种新型Fe-Ga合金磁特性测试装置。建立了该测试装置磁路部分三维有限元磁场分析模型,在该模型基础上通过调整结构和元件尺寸优化了磁路结构,并制作了样机。搭建了磁特性测试装置的实验平台,进行了Fe-Ga合金磁特性测试。实验结果表明,该装置可对Fe-Ga合金磁致伸缩棒材磁致伸缩效应和逆磁致伸缩效应进行静态、准静态和动态测量,测量结果与国外报道的结果一致。设计的磁特性测试装置具有稳定可靠、精度高、操作简单、自动记录等优点。该装置还适用于Fe-Ni、Fe-Co等饱和磁场低的磁致伸缩材料的磁特性测量。  相似文献   
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