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OBJECTIVE: Published guidelines state that allopurinol doses should be adjusted according to creatinine clearance. We investigated whether such dosing provides adequate control of hyperuricemia. METHODS: We studied 250 patients with gout attending rheumatology clinics in South Auckland from 2001 to 2004. Allopurinol dose, creatinine clearance, and serum uric acid (SUA) level were recorded. We analyzed the relationship between recommended allopurinol dose and SUA lowering to 相似文献   
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Segmental mediolytic arteriopathy (SMA) is a rare condition. It was first defined in 1976 and has been well described in the literature, although to date the aetiology of the condition is unknown. In most case reports SMA is diagnosed retrospectively once tissue has undergone histological examination. We present the first known case of SMA of the colic, mid-jejunal, common hepatic, intrahepatic and gastric arteries to be diagnosed at angiography after multiple episodes of undiagnosed intraperitoneal bleeding, and, perhaps related to this, one of the few reported patients with SMA involving multiple intra-abdominal arteries to have survived.  相似文献   
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Women recover from sleep deprivation more efficiently than men, but the mechanism for this difference is unknown. Effects of estrogen on sleep suggest that it could play a role, but the brain targets on which estrogen may act to have this effect have not been identified. Sleep deprivation increases levels of the immediate-early gene protein c-Fos in selected brain regions, but it is unknown whether estrogen modulates this response. We investigated the influence of different levels of exogenous estradiol on the c-Fos response to sleep deprivation in ovariectomized female rats. Female rats were treated with low or high levels of estradiol (mimicking diestrous and proestrous levels, respectively) delivered via subcutaneous silastic tubes. Control ovariectomized females and sham-operated males were implanted with tubes filled with cholesterol. One week after surgery, half of the rats underwent a 3 h period of sleep deprivation during the light phase in a motorized Wahmann activity wheel that rotated constantly at a slow speed, while half were confined to fixed wheels. Immediately after sleep deprivation, animals were killed and their brains processed to detect c-Fos using immunohistochemistry. Sleep deprivation increased the number of c-Fos positive cells in a number of brain areas, including the caudate putamen, medial preoptic area, perifornical hypothalamus, and anterior paraventricular thalamic nucleus. Other areas, including the suprachiasmatic nucleus, posterior paraventricular hypothalamic nucleus, posterior paraventricular thalamic nucleus, arcuate nucleus, and central amygdala, did not respond to 3 h sleep deprivation with a significant increase in c-Fos levels. Levels of c-Fos induced in the selected brain regions by sleep deprivation were not modulated by estrogen levels, nor by sex.  相似文献   
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Monoclonal antibodies against cell surface markers are powerful tools in the study of tissue regeneration, repair, and neoplasia, but there is a paucity of specific reagents to identify stem and progenitor cells in tissues of endodermal origin. The epitope defined by the GCTM-5 monoclonal antibody is a putative marker of hepatic progenitors. We sought to analyze further the distribution of the GCTM-5 antigen in normal tissues and disease states and to characterize the antigen biochemically. The GCTM-5 epitope was specifically expressed on tissues derived from the definitive endoderm, in particular the fetal gut, liver, and pancreas. Antibody reactivity was detected in subpopulations of normal adult biliary and pancreatic duct cells, and GCTM-5-positive cells isolated from the nonparenchymal fraction of adult liver expressed markers of progenitor cells. The GCTM-5-positive cell populations in liver and pancreas expanded greatly in numbers in disease states such as biliary atresia, cirrhosis, and pancreatitis. Neoplasms arising in these tissues also expressed the GCTM-5 antigen, with pancreatic adenocarcinoma in particular showing strong and consistent reactivity. The GCTM-5 epitope was also strongly displayed on cells undergoing intestinal metaplasia in Barrett's esophagus, a precursor to esophageal carcinoma. Biochemical, mass spectrometry, and immunochemical studies revealed that the GCTM-5 epitope is associated with the mucin-like glycoprotein FCGBP. The GCTM-5 epitope on the mucin-like glycoprotein FCGBP is a cell surface marker for the study of normal differentiation lineages, regeneration, and disease progression in tissues of endodermal origin. Stem Cells2012;30:1999-2009.  相似文献   
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Polyacrylamide gel electrophoresis (PAGE) of proteins with subsequent western blotting has become a routine technique for the analysis of proteins from both cultured cells and fresh whole tissue. We have developed a method to extract proteins from methacarn-fixed tissue which renders them suitable for SDS-PAGE and western blotting. With a panel of antibodies to specific intermediate filaments, transforming growth factor-α (TGF-α), and albumin, immunohistochemistry was performed in parallel with western blotting on sections cut from methacarn-fixed samples of normal rat liver and liver from rats treated under a regime which induces oval cell proliferation. Immunohistochemistry enabled the determination of changes in tissue distribution and abundance of the target proteins, which was mirrored by the corresponding western blot data. This technique can be especially effective when used in conjunction with immunohistochemistry. Tissue samples are easy to prepare, avoiding the precautions which need to be taken when handling fresh tissue (Abstract: J Pathol 1994; 173S : No. 41).  相似文献   
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The authors have used transgenic mice to study the activity of a hybrid oncogene made up of 1.25 kb of 5' upstream sequences, derived from the bovine vasopressin gene, promoting the expression of the large T-antigen coding sequences of the early region of simian virus 40. Rather than promoting tumorigenesis in vasopressinergic cells of the hypothalamus, expression and activity of the hybrid oncogene, and consequent tumor formation, were confined to insulin-producing beta cells of the endocrine pancreas and to cells in the anterior pituitary. These observations suggest that the specificity of vasopressin gene expression normally results from an interaction between several regulatory elements, some of which are absent from the hybrid oncogene. The possible relationship between the endocrine tumor syndrome found in the vasopressin-SV40 transgenic mice and familial human multiple endocrine neoplasia is discussed.  相似文献   
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