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31.
The effect of proctocolectomy on the primary sclerosing cholangitis that frequently is associated with chronic ulcerative colitis in patients with both conditions is unknown. We have studied prospectively the progression of clinical, biochemical, cholangiographic, and hepatic histologic features in 45 patients with both primary sclerosing cholangitis and chronic ulcerative colitis to compare these variables in the 20 patients who had undergone proctocolectomy with the 25 who had not. The two groups were similar initially with regard to clinical, biochemical, cholangiographic, and hepatic histologic findings. All patients were followed for a minimum of 1 yr and overall duration of follow-up was similar in both groups (4.1 vs. 3.9 yr). Clinically, new onset of hepatomegaly, splenomegaly, esophageal varices, and ascites did not differ in patients with and without proctocolectomy. Biochemically, the serial changes in bilirubin, alkaline phosphatase, aspartate aminotransferase, prothrombin time, and albumin were similar. Histologic progression on liver biopsy did not differ between groups, nor did changes on serial cholangiograms. Proctocolectomy also had no effect on survival. We conclude that proctocolectomy for chronic ulcerative colitis has no beneficial effect on the primary sclerosing cholangitis in patients with both diseases.  相似文献   
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We have previously shown that normal-density human peripheral blood eosinophils transcribe and translate mRNA for granulocyte-macrophage colony-stimulating factor (GM-CSF) and that the intracellular distribution was granular as assessed by light microscopy immunocytochemistry. The present study was conducted to confirm this apparent association between GM-CSF and the crystalloid granule using a subcellular fractionation method for human eosinophils and immunogold electron microscopy (EM). Highly purified (> 99%, by negative selection using anti-CD16 immunomagnetic microbeads) human peripheral blood eosinophils were obtained from four asthmatic subjects (not taking systemic medication), homogenized and density fractionated (5 x 10(7) cells/subject) on linear Nycodenz gradients. Twenty-four fractions were collected from each cell preparation and analyzed for marker enzyme activities as well as total protein. Dot blot analysis with specific monoclonal antibodies (MoAbs) was used to detect the eosinophil granule proteins major basic protein (MBP) and eosinophil cationic protein (ECP). An anti-CD9 MoAb was used as an eosinophil plasma membrane marker. Lactate dehydrogenase (LDH) was used as a cytosolic marker. Immunoreactivity for GM-CSF was detected by a specific enzyme-linked immunosorbent assay using a polyclonal antihuman GM-CSF antibody and confirmed by dot blot. GM-CSF coeluted with the cellular fractions containing granule markers (MBP, ECP, eosinophil peroxidase, hexosaminidase, and arylsulphatase), but not those containing cytoplasm (LDH+) or membrane (CD9+) markers. EM examination of pooled fractions associated with the peak of GM-CSF immunoreactivity confirmed that they contained crystalloid and small granules, but not plasma membrane. In addition, quantification, using immunogold labeling with an anti/GM-CSF MoAb, indicated preferential localization of gold particles over the eosinophil granule cores of intact cells. Thus, our results indicate that GM-CSF resides as a granule-associated, stored mediator in unstimulated human eosinophils.  相似文献   
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Lymphocyte subsets in primary sclerosing cholangitis   总被引:4,自引:0,他引:4  
As an initial step in testing the hypothesis that immunoregulatory abnormalities are important in the pathogenesis of primary sclerosing cholangitis, we determined the number and percentage of lymphocyte subsets in the peripheral blood of 33 patients with primary sclerosing cholangitis. In these patients, when compared with normal and diseased controls, there was a significant reduction in the total number of circulating T cells because of a disproportionate decrease in Leu-2a (suppressor/cytotoxic) cells. This decrease resulted in a significantly increased ratio of Leu-3a to Leu-2a cells. Patients with cirrhosis had significantly higher Leu-3a/Leu-2a (helper/suppressor) ratios than did noncirrhotic patients; both disease groups, however, had ratios that were significantly higher than controls. The number and percentage of B cells were significantly increased. Alterations in the percentage of B cells correlated significantly with histologic stage and concentrations of gamma globulin, serum IgG, and bilirubin. We conclude that these abnormalities are suggestive of a defect in immunoregulation in primary sclerosing cholangitis, which is not secondary to advanced liver disease alone and appears to be independent of chronic ulcerative colitis,or obstructive jaundice.Presented at the Annual Meeting of the American Gastroenterologic Association, New Orleans, Louisiana, May 19–25, 1984.This work was supported by the Mayo Foundation and Sandoz Inc., East Hanover, New Jersey.  相似文献   
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A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
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手术是脉管性病变治疗的一种手段,其主要作用是与放射治疗及各种药物治疗协同作用。对于血管瘤患者,手术仅限于普萘洛尔治疗无效,出现并发症及位于眼部的病变。整形手术可使血管瘤消退后遗留的面部畸形得到改善。对于一些范围较小的局灶性病变,手术往往可以取得满意的效果;对于巨大、多发的血管瘤,手术治疗往往作用有限,常常为减瘤术。手术患者一般在术前均经过栓塞硬化治疗,这样可以大大减少术中出血。手术无法治愈脉管性疾病,是一种辅助  相似文献   
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One of the most consistent findings to emerge from domestic/intimate partner violence (IPV) research is that IPV tends to “run in the family.” Social learning theories appear to be consistent with empirical data, but almost no attention has been given to alternative explanations, including that genetic factors explain intergenerational transmission of IPV. Data for this study were drawn from wave 4 of the National Longitudinal Study of Adolescent Health (Add Health). Three indicators of IPV were measured and genetic factors accounted for 24% of the variance in hitting one's partner, 54% of the variance in injuring one's partner, and 51% of the variance in forcing sexual activity on one's partner. The shared environment explained none of the variance across all three indicators and the nonshared environment explained the remainder of the variance. These findings point to the importance of genetic factors in the etiology of IPV.  相似文献   
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