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111.
Cytogenetic and histologic correlations in malignant lymphoma 总被引:9,自引:0,他引:9
Koduru PR; Filippa DA; Richardson ME; Jhanwar SC; Chaganti SR; Koziner B; Clarkson BD; Lieberman PH; Chaganti RS 《Blood》1987,69(1):97-102
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change. 相似文献
112.
关于空腹血糖、空腹胰岛素乘积的倒数在流行病学研究中应用的补充说明 总被引:26,自引:0,他引:26
高胰岛素正糖钳夹技术可以测定活体的胰岛素敏感性,但它并不适用于大规模流行病学研究。流行病学研究需要简单的胰岛素抵抗测定法。本文补充报告在空腹血糖(FPG)(75~306mg/dl或4.2~17.1mmol/L)及空腹胰岛素(FIns)(9.7~120mU/L)范围很宽的Pima印第安人群中,正糖钳夹技术测定的胰岛素介导的葡萄糖代谢率(M)与涉及FPG、FIns的多种复合的胰岛素敏感指数的相关性:胰岛素作用指数(IAI)=1/(FPG×FIns)在非糖尿病人群及2型糖尿病人群都与M显著正相关(r>0.7,P=0.0001),而且这两者的相关性强于M与其他指数如FIns或FPG/FIns比值的相关性,也不弱于M与糖负荷后3~5个时间点的血糖、胰岛素曲线下面积乘积的相关性。IAI的五分变量分布情况表明有90.4%的IAI落在所预测的M值五分变量区域或与之相邻的一个五分变量区域之内。1/FPG×FIns虽相对简单但确实与机体的胰岛素敏感性密切相关,它可以做为胰岛素敏感指数在流行病学研究中应用。 相似文献
113.
Regulation of stimulated integrin surface expression in human neutrophils by tyrosine phosphorylation 总被引:4,自引:0,他引:4
The control of the adhesive properties of human neutrophils is an essential element of their defense function. One level at which this control is exerted involves the upregulation of the surface expression of beta 2-integrins. In this study, we have examined the potential involvement of tyrosine phosphorylation in the latter process. Two inhibitors of tyrosine kinases with differing modes of action, erbstatin and herbimycin A, were found to inhibit the expression of CD11b and CD18 stimulated by chemotactic factors (fMet-Leu-Phe or leukotriene B4) or growth factors (tumor necrosis factor alpha). This inhibition was not shared by an inactive analog of erbstatin or by the protein kinase C inhibitor Ro 31-8330. Erbstatin also inhibited the unveiling of activation-specific neoepitopes detected by antibody CBRM1/5. Pretreatment of neutrophils (but not of endothelial cells) with erbstatin inhibited the stimulation of neutrophils' adherence to endothelial cells induced by fMet-Leu-Phe. Augmentation of tyrosine phosphorylation by inhibiting tyrosine phosphatases using hydroperoxyvanadate led to an increased surface expression of CD11b and CD18 and enhanced the adhesion of neutrophils to endothelial cells. Finally, the leumedin NPC 15669, which had previously been shown to inhibit stimulated CD11b expression and neutrophil adherence to endothelial cells and to exhibit anti-inflammatory properties in various in vivo models of inflammation, inhibited the stimulation of tyrosine, phosphorylation induced by fMet-Leu-Phe. Taken together, these data establish a strong correlation between tyrosine phosphorylation and integrin upregulation in stimulated human neutrophils. 相似文献
114.
High prevalence of antibodies to intestinal epithelial antigens in patients with inflammatory bowel disease and their relatives 总被引:4,自引:0,他引:4
STUDY OBJECTIVE: To assess whether healthy members of families of patients with inflammatory bowel disease share an immune reactivity to gut epithelial cell antigens. DESIGN: Assessment of immune reactivity against epithelial-cell-associated components (ECAC). METHODS: Detection of specific anti-ECAC serum antibodies by antibody-dependent cellular cytotoxicity (percent specific lysis) and by immunoblotting (Western blots). PATIENTS: Index cases (131) and first-degree relatives in 17 families with 2 or more affected members, and 13 with only 1 member affected. MAIN RESULTS: Compared with a gastrointestinal disease control group (0.5% +/- 0.8%), specific lysis against ECAC-C (colon-derived) among patients with inflammatory bowel disease was significantly greater in both multiply affected (8.4% +/- 8.2%; P less than 0.01) and singly affected (5.2% +/- 5.4%; P less than 0.05) families. In contrast, specific lysis by patients with other inflammatory processes of the small and large bowel (1.1% +/- 1.4%) or autoimmune disease (0.7% +/- 1.0%) did not differ from that of the gastrointestinal disease control group. Among relatives of patients with inflammatory bowel disease (index cases), specific lysis was also significantly higher than in the control group (4.8% +/- 5.5% for multiply affected, P less than 0.01, and 4.3% +/- 5.5% for singly affected, P less than 0.05). Relatives of patients with chronic inflammatory liver disease had a level of lysis (0.6% +/- 0.9%) similar to that of controls. The prevalence of antibodies to ECAC-C was 69.7% among patients with chronic inflammatory bowel disease, and 55.7% among relatives; both prevalences were significantly higher than that of the control group (8.0%, P less than 0.001). Using small-bowel-derived ECAC, the prevalence of antibodies among patients with inflammatory bowel disease and relatives was also significantly higher than that of controls. Reactivity of sera was directed to a 160- and a 137-kilodalton macromolecule. CONCLUSIONS: Immune sensitization to intestinal epithelial antigens is common in families with chronic inflammatory bowel disease; its high frequency among asymptomatic relatives suggests it may represent a primary phenomenon, perhaps predisposing individuals to gut tissue injury. 相似文献
115.
On PAR: A feasibility study of the Promoting Adult Resilience programme with mental health nurses 下载免费PDF全文
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Is Going Beyond Rasch Analysis Necessary to Assess the Construct Validity of a Motor Function Scale?
Tiffanie Guillot Sylvain Roche Pascal Rippert Dalil Hamroun Jean Iwaz René Ecochard Carole Vuillerot 《Archives of physical medicine and rehabilitation》2018,99(9):1776-1782.e9