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排序方式: 共有771条查询结果,搜索用时 19 毫秒
761.
Jürgen Glas Astrid Konrad Silke Schmechel Julia Dambacher Julia Seiderer Frieder Schroff Martin Wetzke Darina Roeske Helga-Paula T?r?k Laurian Tonenchi Simone Pfennig Dirk Haller Thomas Griga Wolfram Klein J?rg T Epplen Christian Folwaczny Peter Lohse Burkhard G?ke Thomas Ochsenkühn Thomas Mussack Matthias Folwaczny Bertram Müller-Myhsok Stephan Brand 《The American journal of gastroenterology》2008,103(3):682-691
762.
Expression of NK-lineage markers on peripheral blood lymphocytes with T- helper (Leu3+/T4+) phenotype in B cell chronic lymphocytic leukemia 总被引:1,自引:0,他引:1
Heterogeneity within lymphocyte subsets expressing T-helper (T4+/Leu3+) or T-suppressor (T8+/Leu2+) markers was analyzed in 38 patients with B cell chronic lymphocytic leukemia (B-CLL) and in 11 age-matched controls. Co-expression of NK-lineage markers (M1, Leu7) on Leu2+ or Leu3+ cells was investigated by two-color immunofluorescence, and the proportion of granular lymphocytes within each subset was determined by cytochemical staining for acid phosphatase. B-CLL patients and normal controls had similar absolute numbers of cells per microL with T- suppressor phenotype. However, the proportion of Leu2+ cells co- expressing the Leu7 antigen was higher in the B-CLL patients than in the control subjects (54 +/- 3% v 27 +/- 4%, P less than .0001). The absolute number per microL of cells with T-helper phenotype was somewhat decreased in B-CLL patients compared with normal subjects (649 +/- 104 v 799 +/- 33, P less than .02), with a consequent decrease of the helper/suppressor ratio. Furthermore, co-expression of the Leu7 and, more strikingly, of the M1 markers was increased significantly on Leu3+ cells from B-CLL patients compared with normal controls (11 +/- 2% v 2 +/- 0.7%, P less than .002 for Leu7 and 40 +/- 5% v 4 +/- 1%, P less than .00001 for M1). Cytochemical studies showed that a large proportion of Leu3+ cells from B-CLL patients were granular lymphocytes, as suggested by the co-expression of natural killer (NK) cell markers. The emergence of a population of Leu3+ granular lymphocytes with NK markers, which is barely detectable in normal subjects, may provide an explanation for the impairment of T cell functions repeatedly described in B-CLL. 相似文献
763.
764.
Change in antigen specificity of cytotoxic T lymphocytes is associated with the rearrangement and expression of a T-cell receptor beta-chain gene.
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J T Epplen F Bartels A Becker G Nerz M Prester A Rinaldy M M Simon 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(12):4441-4445
Cloned H-Y-specific murine cytotoxic T lymphocytes, which alter antigen specificity in vitro ("aging"), simultaneously exhibit changes in the T-cell antigen receptor beta-chain rearrangements and respective mRNAs expressed. beta-chain cDNA clones were isolated from a library prepared from mRNA of aged killer T cells. The sequence of the beta-chain variable region element (VAK) was found to be identical with germ-line DNA. Four bases at the beta-chain diversity-joining region (D beta--J beta) junction cannot be explained by known germ-line D beta and J beta elements. These results illustrate that in T-cell clones altered antigen specificity correlates with a switch in productive beta-chain rearrangements of the T-cell receptor. When tested for its expression under physiological conditions, significant levels of VAK mRNA were found in normal lymphocyte populations. 相似文献
765.
Wieczorek S Hellmich B Arning L Moosig F Lamprecht P Gross WL Epplen JT 《Arthritis and rheumatism》2008,58(6):1839-1848
OBJECTIVE: Wegener's granulomatosis (WG) and Churg-Strauss syndrome (CSS) belong to the heterogeneous group of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides. Current understanding of their pathogenesis and genetic background is limited. Expression levels of interleukin-10 (IL-10), a potent and pleiotropic cytokine, are largely determined by variations in the gene encoding the IL-10 precursor. This study was undertaken to determine the impact of IL10 polymorphisms on the pathogenesis of both WG and CSS in large cohorts. METHODS: Three single-nucleotide polymorphisms (SNPs) tagging the promoter haplotypes of the IL10 gene (IL10 -3575, IL10 -1082, and IL10 -592) were analyzed in 403 patients with WG and 103 patients with CSS as well as 507 matched control subjects from Germany. In addition, 3 informative SNPs in other parts of IL10 were genotyped. RESULTS: None of the markers or their haplotypes was associated with WG or any of its subgroups classified according to ANCA status, sex, or presence of further WG genetic risk factors. In contrast, the IL10 -3575/-1082/-592 TAC haplotype, part of the extended ancient haplotype IL10.2, was highly significantly associated with ANCA-negative CSS (chi2 = 19.14, P = 0.000012, corrected P = 0.0003, odds ratio 2.16, 95% confidence interval 1.52-3.06). CONCLUSION: These findings challenge those from previous studies of IL10 in WG and provide further evidence that CSS and WG have distinct genetic backgrounds. Because the IL10.2 haplotype has been correlated reproducibly with increased IL10 expression, the possible role of IL-10 in the pathogenesis of ANCA-negative CSS needs to be further elucidated. 相似文献
766.
Steady-state binding of ADP to blood platelets and isolated membranes has not previously been obtained because of complications arising from metabolism of the ligand and dilution due to its secretion from storage granules. In the present studies, competition binding isotherms (n = 9) using paraformaldehyde-fixed platelets showed that [2-3 H]ADP bound to two sites with a small amount (approximately 5% of total) of nonspecific binding: 410,000 +/- 40,000 sites of low affinity (Kd 7.9 +/- 2.0 mumol/L) and 160,000 +/- 20,000 sites of high affinity (Kd 0.35 +/- 0.04 mumol/L) corresponding to the ADP concentration required for activation in fresh platelets (0.1-0.5 mumol/L). All agonists and antagonists examined were able to compete with ADP at the high-affinity site. The strong platelet agonists 2-methylthio ADP and 2-(3- aminopropylthio)ADP competed with ADP at the high-affinity site with dissociation constant values of 7 mumol/L and 200 mumol/L, respectively. The partial agonist 2',3'-dialdehyde ADP and the weak agonist GDP also competed at the high-affinity site with Kd values of 5 mumol/L and 49 mumol/L, respectively. The sequence of binding affinities of other adenine nucleotides at the high-affinity site corresponded to their relative activities as known antagonists of platelet activation by ADP; namely, ADP(Kd 0.35 mumol/L) approximately equal to ATP (Kd 0.45 mumol/L) much greater than AMP (Kd 360 mumol/L). Adenosine and 2-chloroadenosine did not compete with ADP. ADP binding to the high-affinity site was inhibited by p-mercuribenzene sulfonate (Ki 250 mumol/L) but only very weakly by 5'-p- fluorosulfonylbenzoyladenosine (Ki 1 mmol/L). All the above nucleotides also competed with ADP at the low-affinity sites but, because of the high concentrations of competing nucleotide required, dissociation constants at this site were obtained only for ATP (21 mumol/L), 2-MeS ADP (200 mumol/L) and 2',3'-dialdehyde ADP (270 mumol/L). 8-Bromo ADP competed strongly with ADP at the high-affinity site (Kd 0.40 mumol/L) but weakly if at all at the low-affinity site. 8-Bromo ADP inhibited platelet activation induced by ADP (EC50 approximately 100 mumol/L) but not by collagen, thrombin, or ionophore A23187.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
767.
人工髓核假体置入治疗腰椎间盘突出症的疗效分析 总被引:2,自引:0,他引:2
目的:观察已在临床初步开展起来的人工髓核置换术治疗腰椎间盘突出症的中、远期临床疗效及并发症,分析其对策。
方法:纳入2002-02/2004-08南方医科大学附属南方医院脊柱骨病外科采用单枚人工髓核假体置换术治疗单节段腰椎间盘突出症患者98例,获得24~48个月随访患者75例,按平均随访时间达24,36,48个月,分为24个月组(n=30),36个月组(n=23),48个月组(n=22)。选同期采用单纯椎间盘髓核摘除术患者30例作为对照组,评估各组术后临床疗效,主观症状采用Oswestry功能障碍指数问卷表(0%表示正常,越接近100%则功能障碍越严重)和Prolo功能评分表(小于或等于5分为差,6~7分为中等,8~10为优)评价,分析术后影像学检查并测量手术节段活动度和椎间隙高度变化情况,同时观察假体位置情况,腰椎MRI观察假体位置和软骨终板的信号变化情况。腰椎活动度=(腰椎中立角度-前屈角度)+(后伸角度-腰椎中立角度)=后伸角度-前屈角度;为消除X射线放大率的影响,椎间隙高度变化情况采用病变椎间隙后缘高度与上位椎体中部矢状径的比值表示。
结果:75例获得24~48个月随访者,全部进入结果分析。①48个月组2例、36个月组1例发生假体脱出,二次手术取出。其余患者术后临床症状均明显缓解,疼痛消失。②24,36,48个月组及对照组术后末次Oswestry功能障碍指数均较术前降低,差异有显著性意义(14.2%,52.1%;15.5%,55.2%;15.1%,53.6%;15.5%,51.5%;P〈0.05)。③24,36,48个月组及对照组术后末次Prolo能评分均较术前升高,差异有显著性意义(8.5,4.6分;8.6,4.5分;8.7,4.3分;8.4,4.2分;P〈0.05)。④24,36,48个月组同期手术节段腰椎活动度均高于对照组,差异有显著意义(P〈0.05)。⑤24个月组手术节段椎间高度较术前降低约4%、36个月组降低约12%、48个月组降低约18%、对照组较术前降低约25%,各组术前和术后椎间隙高度比值比较,差异具有显著性意义(P〈0.05)。⑥主要并发症:早期出现术后一过性腰痛24例,假体脱出3例。中、远期发现假体下沉32例,软骨终板损伤39例。
结论:单枚人工髓核假体置换治疗腰椎间盘突出症中、远期随访临床疗效肯定,但存在较严重并发症,应慎重开展此项手术。 相似文献
768.
A retrospective study at our hospital determined the race or ethnicity of patients seen in an 8-year period who had formed antibodies to Duffy antigens. During that time, 9876 serologic investigations had been performed as a result of a positive direct or indirect antiglobulin test. Among these samples, sera from 45 previously transfused or pregnant patients contained anti-Fya and two contained anti-Fy3. Twenty-nine of the sera that contained anti-Fya (62%) were from blacks, 12 (25%) were from whites, and 6 (13%) were from Hispanics. Both examples of anti-Fy3 were made by black patients. Red cells (RBCs) from 21 of the black patients were Fy(a-b-), those from 7 were Fy(a-b+), and those from 1 could not be phenotyped. RBCs from 17 of the non-black patients were Fy(a-b+) and those from 1 could not be phenotyped. The population of transfused patients evaluated in this study was 47 percent black, 29 percent white, and 24 percent Hispanic. Calculations based on an expected Fy(a-) frequency of 88 percent in blacks, 33 percent in whites, and 20 percent in Hispanics predict that the racial makeup of the Fy(a-) population at our hospital would be 73 percent black, 18 percent white, and 9 percent Hispanic, which is not significantly different (p = 0.25) from the racial makeup of the patients forming anti-Fya and -Fy3. These data indicate that blacks make antibodies to Duffy antigens as frequently as non-blacks. 相似文献
769.
770.
柯萨奇-腺病毒受体在肾癌组织中的表达及意义 总被引:4,自引:1,他引:4
目的:研究柯萨奇-腺病毒受体(CAR)在肾癌组织中的表达及意义.方法:应用免疫组化SP法检测12例癌旁正常肾组织和48例肾细胞癌组织中CAR的表达.结果:12例正常肾组织全部表达CAR,48例肾细胞癌组织中31例无CAR表达.不同分级CAR表达率分别为Ⅰ级54.5%(12/22)、Ⅱ级23.5%(4/17)、Ⅲ级11.1%(1/9);不同分期CAR表达率分别为Ⅰ期57.9%(11/19)、Ⅱ期30.8%(4/13)、Ⅲ期18.2%(2/11)、Ⅳ期0(0/5).结论:在多数肾细胞癌组织中CAR基因表达丧失;CAR表达变化与肾癌的分级、分期相关,可以作为肾癌分化、转移的重要生物学指标. 相似文献