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51.
医院用血液制品HCV污染情况的调查   总被引:1,自引:0,他引:1  
目的调查医院治疗用血液制品HCV污染情况.方法临床治疗所用的血液制品,在输完后留容器之残液备检.采用酶标免疫法(ELISA)检测.对ELISA检测之阳性标本及在阴性标本中随机抽取9份,采用逆转录双PCR方法检测HCV_RNA.结果血浆白蛋白抗_HCV阳性率458%,新鲜血浆阳性率26%.两种方法检测同一标本,ELISA检测阳性的血液制品中,用PCR证实,并非都有病毒复制;而在ELISA检测的阴性标本中,仍旧有较高的PCR阳性检出.结论血液制品存在着HCV污染,抗_HCV对于HCV感染的诊断价值很高.检测血液制品中的抗_HCV,合理使用血液成份,可防止HCV在医院内传播.  相似文献   
52.
We report a first case of a 19 year old female suffering from an acute lymphatic leukemia, which developed shortly after the initiation of a chemotherapy an intracerebral hemorrhage and fatal multiple brain abscesses caused by Bacillus cereus. There is much evidence that Bacillus cereus in immunocompromised patients leads to a localized, necrotizing tissue infection due to the production of potent toxins and usually results in rapid and fulminant tissue destruction. Bacillus species has an special affinity for the CNS mediated by phospholipase C, which tends to associate with the lipid membranes of the brain.  相似文献   
53.
Keratinocyte intercellular adhesion molecule (ICAM)-I expression is induced by interferon (IFN)-gamma. It has been previously reported that IFN-beta suppresses IFN-gamma-induced ICAM-I expression in A431 cells, a human squamous cell carcinoma cell line. In this study, the suppression mechanisms were investigated at the post second messenger level. Both 12-O-tetradecanoylphorbol-13-acetate (TPA) and calcium ionophore (A23187) induce ICAM-I expression in A431 cells. ICAM-I expression induced by either was not suppressed with cotreatment with IFN-beta. Furthermore, IFN-beta did not inhibit the translocation of protein kinase C (PKC) by TPA. It appears that the pathways involved in ICAM-I expression induced by activation of PKC or increased in intracellular Ca++ are not affected by IFN-beta.  相似文献   
54.
Interferon (IFN) therapy is of proven efficacy in chronic hepatitis C, but it is not universally effective and is often limited by side effects. Cyclosporine A (CsA) is a potent immunosuppressant widely used in organ transplantation. We conducted a pilot study to determine whether CsA therapy could affect aminotransferase activity and hepatitis C virus RNA levels in patients with chronic hepatitis C. Cyclosporine A was administered to 10 patients (mean age of 59 years; male: female = 9:1) who did not respond to IFN therapy previously and who had elevated serum alanine aminotransferase (ALT) values for at least 6 months. All patients were positive for HCV-RNA by RT-PCR with genotype 1b. Their mean duration of hepatitis was 15 years. Oral CsA was given for 3 months in a dose that was increased at 1 month intervals from 1.5–2.0 to 2.0–3.0 and 3.0–4.0 mg/kg per day. All patients completed the treatment schedule, although two patients developed mild non-symptomatic hypertension. Serum ALT levels gradually decreased in all but one patient. The mean percentage decrease was 59.5% at the end of therapy (from 153 ± 82 to 62 ± 48 IU/L; P < 0.02). The ALT levels fell to the normal range in five patients, although once therapy was discontinued the enzyme levels tended to return to pretreatment levels. Serum aspartate aminotransferase and g-glutamyl transpeptidase levels similarly decreased. The serum HCV-RNA titre, determined by competitive RT-PCR, did not change in any patient throughout the study period. There were no appreciable alterations in other laboratory tests, such as serum creatinine levels and lymphocyte subsets, except for an increase in serum alkaline phosphatase levels. These findings suggest that CsA, even in a relatively low dose, reduces serum aminotransferase levels without serious side effects in patients with chronic-hepatitis C, although an antiviral effect was not noted.  相似文献   
55.
钩体基因疫苗对豚鼠延髓原癌基因表达的影响   总被引:1,自引:1,他引:0  
张燕华  李峻 《华西医学》1998,13(2):166-169
我们的研究已表明,赖型017株钩体外膜疏水蛋白OmpL39是稳定的免疫原,在此我们分别用OmpL39与钩体死菌苗和生理盐水对照免疫豚鼠,研究OmpL39的免疫保护作用和免疫机理,对OmpL39的抗原特异性刺激引起中枢原癌基因(Cfos基因)表达进行了观察。结果表明,OmpL39在豚鼠体内能产生高效价的阳性抗体,免疫保护率为100%。在OmpL39对中枢Cfos基因表达的影响中,我们观察到OmpL39免疫的豚鼠较空白和死菌苗组Cfos表达明显少于死菌苗组和空白对照组(p<005)。提示OmpL39能特异性地抑制Cfos基因的表达,减轻强毒钩体对动物体内的病理损伤,有较死菌苗强的免疫保护作用。  相似文献   
56.
57.
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   
58.
A set-up for D.C. recordings of slow ocular potentials such as the c-wave of the electroretinogram (ERG) as well as the fast oscillation (FO), the light peak (LP) and the dark trough (DT) in both clinical and experimental work is described. It includes matched calomel half-cells connected by saline-agar bridges to a corneal contact lens on the eye and a reference chamber on the forehead, a low-drift differential-input D.C. amplifier, an A/D converter, a computer, a thermoprinter, a flexible disc memory, a plotter, and a device for light stimulation controlled by the computer.Examples of the usefulness of the set-up in clinical work are shown in the form of D.C. c-wave ERGs of normal subjects as well as of patients with vitelliform macular degeneration, choriocapillaris atrophy, and retinitis pigmentosa. The direct corneal recording of the FO and LP is demonstrated as well. The different origins of the standing potential (SP) of the eye, the ERG c-wave, the FO and the LP are reviewed briefly.  相似文献   
59.
Abstract. The aim of the study was to determine the role of peripancreatic lymph node swelling in systemic immunological alterations during chronic hepatitis C (HC). The prospective study was carried out as a clinical study in a university hospital. Clinical, haematochemical and ultrasonographic findings in 182 patients were studied. Ultrasonography was performed by the same operator and the findings were evaluated blind without the operator knowing the clinical and haematochemical parameters. Hepatitis B virus (HBV) markers, anti-HCV antibodies. LKMl, cryoglobulinaemia, rheumatoid factor and anti-tissue antibodies were determined. Liver biopsy was carried out in 43 of the 182 patients. One or two pathological peripancreatic lymph nodes (PLNs) were present in 30 of the 182 patients and, of the 30, 28 were anti-HC positive. Only one patient in the non-PLN group was positive for anti-HCV, there being statistical significance ( P <0.0001) between the PLN and non-PLN groups. In HCV-positive patients, extrahepatic immunological manifestations were observed (cryoglobulinaemia; positivity to anti-smooth muscle, antinuclear and antimitochondrial antibodies; positivity to rheumatoid factor and LKMl). In five patients the presence of focal lymphocytic aggregates was detected by biopsy, whereas one patient presented typical ocular lesion of Mikulicz's syndrome. Our results may confirm the marked lymphotropism shown by the HC virus and indicate more complex immune system involvement, especially in view of the coexisting signs of immune system involvement related to the presence of intrahepatic cellular aggregates detected in our study. We believe that the peripancreatic adenopathy in chronic HCV hepatitis is an important diagnostic sign and may indicate an involvement of the C virus in the still unexplained extrahepatic immunological disorders.  相似文献   
60.
维生素C浸泡羊膜对眼碱烧伤后移植的可用性研究   总被引:2,自引:0,他引:2  
张奕霞  张明昌 《眼科新进展》2006,26(11):836-838
目的探讨维生素C浸泡羊膜的特性和生物活性物质的改变,以求为维生素C浸泡羊膜在眼碱烧伤羊膜移植中的合理应用提供依据。方法维生素C浸泡新鲜羊膜、保存1月羊膜,分别观察其大体物理特性、光学显微镜观察组织特性、免疫组织化学检测细胞因子的表达。结果维生素C浸泡羊膜与非浸泡羊膜的大体物理特性及光学显微镜观察组织特性无显著差别、部分细胞因子的活性表达无改变。结论维生素C浸泡羊膜不改变羊膜的组织学特性及部分细胞因子的活性,可以方便、安全地应用眼碱烧伤的移植治疗。  相似文献   
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