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61.
目的 探讨Fas/Apo-1(CD95)在下肢静脉性溃疡的表达及意义.方法 采用流式细胞技术、半定量逆转录-聚合酶链反应(RT-PCR)和免疫组织化学方法检测不同体位下肢外周血和局部皮肤Fas/Apo-l(CD95)的表达.结果 溃疡组平卧位、下垂位血液中Fas/Apo-1(CD95)阳性细胞数分别为41.45±14.25、40.20±12.42,mRNA为0.74±0.33、0.78±0.22,皮肤中阳性细胞数为42.62±22.19、46.50±20.12,分别与无溃疡组和对照组比较,差异均有统计学意义(P<0.05);无溃疡组和对照组比较,差异无统计学意义(P>0.05);不同体位之间Fas/Apo-1(CD95)阳性细胞数和含量比较,差异无统计学意义(P>0.05).结论 Fas/Apo-1高表达可能与下肢静脉性溃疡发生密切相关.  相似文献   
62.
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   
63.
Microinjections of Leu-enkephalin into the dorsal vagal complex induced hypotension and bradycardia. Both naloxone, given at a dose conferring selectivity for μ receptors, and the S antagonist ICI 154,129 prevented the cardiovascular effects of Leu-enkephalin. Naloxone was also found to decrease the gain of the baroreflex. These results suggest that Leu-enkephalin is involved in cardiovascular regulation through activation of δ-, and possibly μ-, opioid receptors in the dorsal vagal complex.  相似文献   
64.
评价了PPV系列衍生物的电学性质、非线性光学性质及其应用。  相似文献   
65.
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   
66.
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   
67.
68.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C.  相似文献   
69.
N┐(4┐乙氧苯基)苯甲酰胺类化合物的合成及抗炎、抗变态反应活性研究周玉新1)党永红刘建飞2)徐颖刘百里(沈阳药科大学制药系,沈阳110015)郑文义(东北第六制药厂,沈阳110043)1981年,刘百里等〔1,2〕发现和研制的新药益肤酰胺,经药理实...  相似文献   
70.
We have investigated the ontogeny of MHC class I, class II, CD45, and macrophage antigens in wholemounts of normal human fetal retina at 10–25 weeks gestation (WG) using monoclonal antibodies and immunogold histochemistry. MHC class I antigens were expressed on retinal vascular endothelial cells and provided a useful marker of vessel organization from 14–25 WG. Microglial cells expressed immunoreactivity to MHC class I, class II, and CD45 antigens from 10 WG (pre-vascularization) and macrophage S22 (Mac S22) antigen from 14 WG (post-vascularization), although none of the antigens tested were detected on neuronal or macroglial elements. Microglia expressing MHC, CD45, and macrophage antigens occurred in both ramified and rounded forms with no close correlation being observed between morphology and antigenicity. The numbers of immunoreactive cells labeled with each of the four markers increased steadily throughout gestation in all specimens studied. Equivalent numbers of microglia expressed MHC class I, class II, and CD45 antigens in retinae at similar gestational ages; however, our data indicate that microglia expressing Mac S22 antigen comprise approximately 40% or less of the population of MHC and CD45-immunoreactive cells during development. Topographical analyses suggest that MHC class I, class II, and CD45-positive microglia enter the retina from both the peripheral retinal margin and the optic disc from at least 10 WG; Mac S22-positive cells appear in association with the development of the retinal vasculature and enter the retina via the optic disc after 14 WG. © 1995 Wiley-Liss, Inc.  相似文献   
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