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101.
Although it is agreed upon by most that adequate and timely bile decompression can preserve or even improve existing liver function much debate centers on whether pre-existing liver cirrhosis can also be reversed. To help answer this question we analyzed data on 47 children with choledochal cyst disease (CD) who underwent simultaneous liver biopsy during bile decompression surgery. We collected data on two groups of children with CD spanning two different time periods: January 1985 through November 1994 (Group A) and June 1995 through November 1999 (Group B). In Group A 37 children (16 boys and 21 girls ages 5 days to 10 years) underwent simultaneous liver biopsy during elective definitive surgery for CD. In Group B ten children (five boys and five girls age one month to 7 years) underwent liver biopsy twice: first during initial cyst decompression for acute obstruction and second during elective definitive surgery after resolution of acute disease. Degree of liver cirrhosis was based on a modified World Health Organization classification system (0-IV). In Group A 15/37 (40.5%) had significant liver cirrhosis at time of biopsy (III or IV) with altered liver function in all cases; eight of nine had normal liver function on follow-up, six were lost to follow-up. In Group B seven of ten (70%) had less liver cirrhosis on pathology at second operation with three unchanged; nine of ten (90%) regained normal liver function. We conclude that bile duct obstruction is the main cause of liver cirrhosis in children with CD. Adequate and timely bile decompression can restore normal liver function and even reverse severe cirrhosis.  相似文献   
102.
Mantle Cell Lymphoma (MCL) is a well-known histological and clinical subtype of B-cell non-Hodgkin's Lymphomas. It is usually characterized by an aggressive disease course, presenting with advanced stage disease at diagnosis and with low response rates to therapy. However few cases of indolent course MCL have been described. We herein report a case of MCL with splenomegaly and peripheral blood involvement as main clinical features. The patient underwent moderate dose splenic radiation therapy and achieved spleen downsizing and peripheral blood complete remission. Splenic irradiation has been extensively used in the past as palliative treatment in several lymphoproliferative disorders and a systemic effect and sometimes peripheral blood complete remissions have been observed. Mainly advocated mechanisms responsible for this phenomenon are considered direct radiation-induced apoptotic cell death, immune modulation via proportional changes of lymphocyte subsets due to known differences in intrinsic radiosensitivity and a radiation-induced cytokine release. The peculiar intrinsic radiosensitivity pattern of lymphoid cells could probably be explained by well-defined individual genetic and molecular features. In this context, among NHLs, MCL subtype has the highest rate of ATM (Ataxia Teleangiectasia Mutated) inactivation. While the ATM gene is thought to play a key-role in detecting radiation-induced DNA damage (expecially Double Strand Breaks), recent in vitro data support the hypothesis that ATM loss may actually contribute to the radiosensitivity of MCL cells. ATM status was retrospectively investigated in our patient, with the tool of Fluorescence In Situ Hybridization, showing a complete inactivation of a single ATM allele secondary to the deletion of chromosomal region 11q22-23. The presence of this kind of cytogenetic aberration may be regarded in the future as a potential predictive marker of radiation response.  相似文献   
103.

Background  

Public health research characterising the course of life through the middle age in developing societies is scarce. The aim of this study is to explore patterns of adult (15–64 years) mortality in an Ethiopian population over time, by gender, urban or rural lifestyle, causes of death and in relation to household economic status and decision-making.  相似文献   
104.
The strontium content of bone has hitherto been impossible to measure noninvasively. A novel dual-photon absorptiometry (DPA) method was developed. 241Am (59.5 keV) and 133Ba (356 keV) were used as radiation sources. The linearity of the DPA method was studied in monkey bones ex vivo after treatment over 52 wk with strontium ranelate. The bone strontium expressed in terms of the percentage molar ratio SrHA/(SrHA + CaHA) x 100%, where HA denotes hydroxyapatite, was measured (1) by the DPA method and (2) by inductively coupled plasma-atomic emission spectrophotometry at the same distal site of the femur. The results correlated significantly: y = 0.33%Sr + 1.086x; r = 0.976; standard error of the estimate (SEE) = 0.57%Sr. In order to measure the accuracy error of Sr%, 30 normal volunteers were measured. Their mean values did not differ significantly from zero and the SD was 0.5%. The radiation dose was small, the equivalent whole-body dose to human subjects being 0.005 micro Sv. This novel DPA method is likely to be successful for bone strontium measurement in humans.  相似文献   
105.
The blood flow in an experimental adenocarcinoma in the rat liver was determined with the 133Xe-washout technique before and after hepatic artery ligation (HAL). There was an initial reduction of the washout of 50%. This was further reduced after 1 day by 50%, which was maintained for 7 days. Seven days after HAL or sham procedures the 133Xe-washout was of similar magnitude in the liver tumours, although after the sham procedure the tumours were larger (3.4 g vs. 1.5 g). The estimated tumour blood flow was then approximately 0.04 ml x min-1 x g-1. The influence on normal liver parenchyma of HAL was a reduction at 30 minutes, which was maintained for 7 days. Postacton--a synthetic vasopressin--did not influence the 133Xe-washout in normal liver parenchyma in non-tumour, as well as in tumour-bearing animals. There was no influence of Postacton on the 133Xe-washout in the liver tumours. Thirty minutes after HAL Postacton gave a reduction of blood flow in normal liver parenchyma of tumour-bearing animals, which is thus only from the portal vein. In tumours Postacton did not significantly reduce the tumour blood flow immediately after HAL.  相似文献   
106.
The pharmaceutical industry can be divided into a top tier of about 30 major league companies and a second tier (minor league) comprising several thousand. This paper focused on the second tier and the particular challenge of minor league companies—especially niche players—to balance operating requirements and strategic ambitions within limited and limiting resources. In the authors' experience, survival as a niche player requires not only that the company stays on the technology frontier but also that risk willingness and innovative behavior be characteristic of managers' mindset. To this end, the authors share 13 “ground rules” to perform appropriately as a niche player. © 1993 wiley-Liss, Inc.  相似文献   
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109.
In a retrospective analysis of 819 patients operated on for gallbladder disease, the costs and mortality rates were compared for 2 different strategies: (a) routine use of intraoperative cholangiography, or (b) selective use of intraoperative cholangiography on patients fulfilling at least 1 of 4 common clinical criteria. Selective use led to lower costs and lower mortality rates. The main reason for this outcome was that the benefits of detecting more stones in the bile duct by the routine use of cholangiography were counterbalanced by an increase in costs and risks because false-positive operative cholangiograms led to a greater number of unnecessary choledochotomies.  相似文献   
110.
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