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141.
CD44v6和组织蛋白酶D表达与食管癌预后的关系   总被引:2,自引:0,他引:2  
目的 研究CD4 4v6和组织蛋白酶D(cathepsinD ,CD)表达与食管癌生物学行为的关系。方法 应用免疫组化法 ,检测 6 5例食管鳞状细胞癌组织中CD4 4v6和CD表达水平。结果 在食管癌中CD4 4v6和CD表达阳性率分别为 5 8.5 %和 6 4 .6 %。CD4 4v6和CD表达均与肿瘤分级、浸润、淋巴结转移和预后相关。结论 CD4 4v6和CD异常表达与食管癌的病理生物学行为密切相关 ,可作为是预测食管癌转移潜能和评估食管癌预后的客观指标  相似文献   
142.
Infusion of 1 μg of carbachol, a potent cholinergic agonist, into the lateral septum of the urethane-anaesthetized rat systematically caused the induction of clear-cut hippocampal theta (θ). However, infusion of an equivalent amount of the drug into the hippocampus, close to the recording electrode, failed to induce θ in 50% of the animals and produced a mixture of θ waves and desynchronized activity, resulting in atypical EEG patterns, in the remaining subjects. Both carbachol EEG effects were blocked by intraseptal infusion of the antimuscarinic agent, atropine. Our data demontrate that muscarinic receptors in the septum are predominent sites for cholinergic agonist-antagonist action capable of generating or suppressing hippocampal θ in the rat. They also indicate that intraseptal cholinergic mechanisms play an important role in the initiation and generation of this rhythm.  相似文献   
143.
Deletions of chromosome 20q are associated with myeloid malignancies and have been previously shown to arise in a multipotent progenitor of both myeloid and B cells. However, B-cell differentiation from the abnormal progenitor was impaired. The CD40 antigen is a surface glycoprotein which is expressed in B cells and haemopoietic stem cells and is important for B-cell growth and development. Following the recent mapping of CD40 to chromosome 20q we sought to determine its position relative to 20q deletions. Analysis of lymphoblastoid cell lines carrying 20q deletions placed CD40 within a 19–21 cM interval which is almost coincidental with the common deleted region defined by previous analysis of patient samples. Our results raise the possibility that genetic alteration of this locus may contribute to the pathogenesis of myeloid disorders associated with 20q deletions.  相似文献   
144.
CD24 expression on human keratinocytes   总被引:4,自引:0,他引:4  
Abstract: CD24 or Nectadrin is a cell surface glycoprotein expressed in pre-B lymphocytes, T lymphocytes, neurons, muscle cells and carcinoma cells. Its function is not completely known, but it has been suggested that it is involved in cell adhesion and signalling. CD24 has recently been identified as the human molecule homologous to the murine heat-stable antigen (HSA). HSA is expressed by murine keratinocytes and delivers costimulatory signals in T-cell activation. Long-term cultures of normal human keratinocytes (HKC) were obtained from skin of human female breast sections and either left untreated or were treated with phorbol-12-myristate-13-acetate (PMA) at 10–100 ng/ml, calcium 0.5–2 mM or IFN-γ 100–1000 U/ml, for 24–48 h. Using RT-PCR and flow cytometry we showed that HKC express low levels of CD24 even under basal conditions, and the treatment with calcium, PMA or IFN-γ increased levels of CD24 mRNA and protein. To the best of our knowledge, this is the first report to measure CD24 expression and production by cultured HKC in basal conditions and after stimulation. Further studies are needed to determine biological and therapeutical relevance of these findings.  相似文献   
145.
146.
风湿性心脏病二尖瓣置换术中细胞因子水平的变化   总被引:1,自引:0,他引:1  
目的测定风湿性心脏病二尖瓣置换术中细胞因子水平,了解它们的变化规律。方法 11例体外循环(CPB)下二尖瓣置换术患者,分别于术前,主动脉阻断前,主动脉阻断后5min,主动脉开放后10min、1h、2h、4h、24h测定白介素6(IL-6)、白介素8(IL-8)、白介素10(IL-10)以及肿瘤坏死因子(TNF)。结果IL-6、IL-8、IL-10水平在CPB开始后逐渐升高,在主动脉开放后2h左右达到高峰(P<0.01)。之后逐渐下降,到主动脉开放后24h已显著下降。TNF水平在CPB开始后逐渐升高,在主动脉开放后24h仍维持在很高的水平(P<0.01)。结论CPB下二尖瓣置换术中既有促炎因子水平的升高,又有抗炎因子的激活。  相似文献   
147.
Superoxide release in neutrophils and sera levels of interleukin 8 (IL-8) were determined in 15 patients with complicated acute myocardial infarction (MI) and 15 patients with uncomplicated MI. All patients showed increased superoxide release in unstimulated and stimulated neutrophils compared with healthy control subjects, indicating priming of these cells. Superoxide release of unstimulated or stimulated neutrophils was found to be significantly higher in patients with complicated MI than in patients with uncomplicated MI. Thrombolytic therapy did not affect the rates of superoxide release. The neutrophil chemoattractant/activator IL-8 was detected in the sera of all patients, with significantly higher levels in those with complicated MI. The highest levels of IL-8 were detected at admission to the Coronary Care Unit and significantly decreased thereafter, suggesting its contribution to neutrophil-mediated tissue injury. The high levels of IL-8 may be one of the major contributors to the priming of neutrophils in these patients.  相似文献   
148.
Thirty patients diagnosed with breast cancer were included in a prospective randomized study comparing the in vivo priming effect of bioequivalent doses of glycosylated (lenograstim) and nonglycosylated (filgrastim) rG-CSF administration. Analysis of the efficacy of equivalent biological doses of both rG-CSFs showed no significant differences either in the mobilization of the subpopulations of PBPC considered (CD34+, CD34+/38, CD34+/DR), the content of such CD34+ cell subsets in the leukapheresis product, or the cost of the mobilization and collection procedures between both recombinant molecules. These results suggest that priming with bioequivalent doses of the two commercially available forms of glycosylated or nonglycosylated rG-CSF has a similar in vivo effect on PBPC mobilization.  相似文献   
149.
Abstract: Our current understanding of human haematopoietic stem cell biology is based in part on the characterization of human CD34+ bone marrow cell differentiation in vitro. CD34 is highly expressed on early stem cells and haematopoietic progenitor cells with clonogenic potential and is gradually lost during differentiation and commitment. However, CD71 (transferrin receptor) is expressed at low levels on early stem cells and generally increases during haematopoietic progenitor cell proliferation. We reasoned that the combination of these surface markers would provide a useful framework for the simultaneous analysis of multiple lineage differentiation of CD34+ haematopoietic progenitor cells in liquid culture. In this report, we identify the phenotype of distinct subpopulations of myeloid, erythroid and lymphoid cells in liquid suspension culture using differential expression of CD34 vs. CD71 in combination with specific lineage markers. Freshly isolated human CD34+ bone marrow cells were introduced into suspension culture and monitored over a 6-d period using 3-colour flow cytometry. This is the first demonstration that differential expression of CD34 vs. CD71 can be used to simultaneously monitor differentiation of multiple haematopoietic cell lineages in liquid suspension culture, facilitating the study of cytokine-, drug- or chemical-induced alterations in haematopoietic progenitor cell differentiation in vitro.  相似文献   
150.
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