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951.
H1-blockers are often added to the standard treatment of acute sinusitis, but this is not supported by a controlled study. A multicentric, randomized, double-blind, placebo-controlled, parallel-group study was done in 139 allergic patients (15–65 years) to assess the adjunct efficacy of loratadine in acute exacerbation of rhinosinusitis. Sinusitis was diagnosed by symptoms and confirmed by rhinoscopy and sinus radiograph. Allergy was characterized by skin tests, RAST, and history. Patients were treated with antibiotics (14 days), oral corticosteroids (10 days), and loratadine (10 mg OD) or placebo (28 days). Treatment efficacy was assessed over 28 days by symptom scores quoted daily by patients. Physicians also rated total symptom scores at entry and at day 28. At entry, both groups had similar symptoms. Placebo-treated patients improved significantly, but patients who received loratadine had a significantly greater improvement in sneezing ( P =0.003) after 14 days, and in nasal obstruction ( P =0.002) after 28 days. Physicians found that patients receiving loratadine were significantly improved compared to placebo patients ( P =0. 0125). Loratadine in addition to standard therapy was found to improve the control of some symptoms of sinusitis.  相似文献   
952.
An interleukin (IL)-4 dependant mouse T cell clone 8.2 derived from an IL-2-dependent T cell line was characterized. As measured by flow cytometric analysis and Northern blotting, it expresses IL-2 receptor β (IL-2Rβ) and γ (IL-2Rγ) chains, but has lost expression of IL-2 receptor α chain (IL-2Rα). To investigate the properties of the mouse IL-2Rβγ complex and the role of IL-2Rα gene expression, this clone was further studied. T cell clone 8.2 has lost the capacity to bind 125I-labeled human IL-2 under experimental conditions able to detect intermediate-affinity IL-2R in human cells. Mouse IL-2 is unable to block the binding of mAb TMβ1 to 8.2 cells. Under the same experimental conditions, mouse IL-2 blocks the binding of TMβ1 to C30-1 cells expressing the IL-2αβγ complex. Since TMβ1 recognizes an epitope related to the IL-2 binding site of IL-2Rβ, these results can be taken as a demonstration that mouse IL-2Rβγ does not bind mouse IL-2. Furthermore, T cell clone 8.2 does not proliferate in response to recombinant mouse or human IL-2. On the other hand, T cell transfectant lines expressing heterospecific receptors made of the human IL-2Rβ and mouse IL-2Rγ chains bind 125I-labeled human IL-2 and proliferate in response to IL-2. This establishes the difference between mouse and human IL-2Rβ chains. Transfection of T cell clone 8.2 with human IL-2Rα genes restores their capacity to proliferate in response to IL-2. In addition, all transfectants grown in IL-2 express the endogeneous mouse IL-2Rα chain. When grown in IL-4, the endogeneous mouse IL-2Rα gene remains silent in all these transfectants. These results show that, contrary to the human, the mouse does not express an intermediate-affinity IL-2R. Expression of the IL-2Rα gene is therefore required for the formation of the functional IL-2R in mice.  相似文献   
953.
Summary In three patients treated with cephalosporins (one patient with latamoxef, two patients with cefazedone) vitamin K1 was injected to investigate whether this was followed by an increase in vitamin K1 2,3-epoxide plasma concentrations as compared to controls. Such a rise in K1-epoxide concentrations in the plasma can be demonstrated following treatment with coumarins. This reflects an inhibition of the vitamin K1-epoxide reductase in the liver. Coumarins are thought to induce hypoprothrombinaemia by such a mechanism. In all three patients we found a considerable increase in the vitamin K1-epoxide plasma concentrations following injection of 10 mg vitamin K1, whereas in normal subjects only traces of K1-epoxide could be detected (<0.030 µg/ml). The K1-epoxide concentrations found in our three patients treated with cephalosporins were 0.12, 0.16 and 0.19 µg/ml, respectively. This indicates that latamoxef or cefazedone might reduce clotting factor synthesis by a coumarin-like mechanism of action in these patients. Although the effect of cephalosporins in enhancing vitamin K1-epoxide plasma concentrations is less than that of coumarins, it might cause severe hypoprothrombinaemia in the presence of latent vitamin K deficiency.Abbreviation PT prothrombin time - TT thrombin time - PTT partial thromboplastin time - PC platelet count - ICU intensive care unit - EEG electroencephalogram - K1-epoxide vitamin K1 2,3-epoxide  相似文献   
954.
Accumulating evidence indicates that tumor viruses represent a major etiological factor in a significant portion of human cancers. These cancers include human papillomavirus induced anogenital cancers, hepatitis B and C virus associated hepatocellular carcinomas, nasopharyngeal carcinomas and lymphomas linked to Epstein-Barr virus infection, and human T cell leukemia virus associated adult T cell leukemias. This review summarizes the recent progress made in understanding the molecular mechanisms of viral carcinogenesis, with a particular focus on the interaction of viral factors with cellular tumor suppressor proteins. The functional inactivation of tumor suppressor proteins may represent a common strategy by which several tumor viruses contribute to malignant cell transformation.Abbreviations EBV Epstein-Barr virus - E6AP E6-associated protein - HBV Hepatitis B virus - HCC Hepatocellular carcinoma - HPV Human papillomavirus - HTLV Human T cell leukemia virus - pRb Retinoblastoma protein - RB Retinoblastoma - SV40 Simian virus 40  相似文献   
955.
兰州地区汉族人群HLA-A、B和DRB1等位基因多态性分析   总被引:1,自引:0,他引:1  
目的分析兰州地区汉族人群HLA-A、B和DRB1位点等位基因多态性特点。方法采用序列特异性引物聚合酶链反应技术对兰州地区200名健康无血缘关系的汉族个体HLA-A、B和DRB1基因座进行分型,并与西北、北方和南方汉族、西北回族、维吾尔族和藏族人群进行比较。结果兰州汉族人群中HLA-A基因座共检出14个等位基因,以A*02,A*11,A*24,A*33,A*30,A*01和A*31基因最常见;HLA—B基因座共检出32个等位基因,以B*40,B*15,B*46,B*13,B*51,B*60,B*58和B*44基因最为常见;HLA-DRB1基因座共检出13个等位基因,最多见的基因依次为DRB1*09.DRB*15,DRB1*12,DRB1*04,DRB1*11,DRB1*07,DRB1*08和DRB1*14,接近北方汉族而与南方汉族有差异,与西北回族无明显差异,但与西北维吾尔族和藏族差异有统计学意义。结论兰州地区汉族人群HLA-A、B和DRB1位点等位基因多态性与南、北汉族人群存在不同程度的差异,与西北维吾尔族和藏族差异显著。  相似文献   
956.
目的 研究HIV-1膜蛋白(Env)特定糖基化位点改造对Env免疫原性及功能性假病毒形成能力的影响.方法 采用环形诱变,DpnⅠ筛选的方法对Env进行定点突变,单周期感染试验检测功能性假病毒形成能力,免疫小鼠,利用假病毒中和试验与ELISPOT分别检测突变对中和抗体和T细胞分泌Env特异的IFN-γ的影响.结果 N197Q突变体使Env诱导中和抗体的能力提高而诱导T细胞分泌Env特异的IFN-γ的能力降低,并使Env不能形成功能性假病毒;G2突变体(N624Q,N637Q)诱导的中和抗体能更好地中和假病毒74-2,仉中和假病毒Wt的能力下降,对Env诱导T细胞分泌Env特异的IFN-γ的能力和功能性假病毒形成无明显影响.结论 特定糖基化位点的改造影响假病毒的形成及Env的免疫原性.  相似文献   
957.
A number of HLA alleles have been newly identified. This concerns HLA-A*0310, A*2907, B*4435, Cw*0206, Cw*0506, of which Cw*0206 was found in three unrelated individuals, all B*4002 positive. Some other alleles are also presented but confirm earlier detected sequences: A*3106, Cw*0314, DRB1*0322, and DRB1*1433. Moreover, we identified B*3924 in a bone marrow transplant recipient and in five of six unrelated stem cell donors, selected for this patient. In all cases, B*3924 was found on a haplotype combining A*0201, B*3924, Cw*0701, and DRB1*1303. The observation of this extended haplotype is of importance for the selection for stem cell transplantation. Cells expressing B*3924 and B*4435 were typed by serology as B39 and B44, respectively. Cells expressing HLA-A*0310 do not express A3 but type as A-Blank.  相似文献   
958.
目的:探讨FIZZ1在ApoE基因敲除小鼠粥样斑块内的表达。方法:C57BL/6JApoE基因敲除鼠及C57BL/6J野生型小鼠各9只,分别喂食高脂饲料及普通饲料,24周后处死,自主动脉根部至腹主动脉离断整支血管,石蜡包埋后作连续切片,行HE染色及FIZZ1免疫组化,检测血管斑块内FIZZ1表达情况,RT-PCR检测斑块内FIZZ1mRNA表达。结果:ApoE基因敲除鼠高脂饲养24周后,主动脉根部动脉粥样硬化明显,斑块体积较大,免疫组化及其RT-PCR可见FIZZ1及其mRNA在粥样硬化斑块内明显表达,同龄野生型C57BL/6J鼠血管壁内未见FIZZ1及其mRNA表达。结论:FIZZ1能在动脉粥样硬化斑块内表达。  相似文献   
959.
目的研究以重组蛋白作为包被抗原检测口蹄疫病毒(FMDV)感染后的动物血清中特异性抗体的可能性,为建立一种非病毒颗粒的ELISA检测试剂盒提供实验依据。方法利用自行构建表达的O型口蹄疫病毒VP1表位肽重组蛋白(VP1epi)作为包被抗原,采用间接ELISA方法确定抗原的最佳工作浓度和包被方法,优化各项实验条件,并以FMDV感染后的豚鼠血清作为标准阳性血清确定ELISA方法的特异性和灵敏度。结果FMDV感染后的阳性豚鼠血清可以很好地识别VP1epi重组蛋白,用此蛋白包被检测抗FMDV抗体的灵敏度可达1∶3200,并证明所检测的抗体是FMDV特异性的。结论VP1epi重组蛋白可以替代FMDV颗粒用于建立检测抗FMDV抗体的ELISA试剂盒。  相似文献   
960.
We report here the identification of a novel DQB1*06 allele, DQB1*0618, found in a bone marrow donor. The new allele was detected during routine DNA-based HLA typing by an ambiguous pattern of probe hybridization, obtained by polymerase chain reaction using sequence-specific oligonucleotides (PCR-SSO). Molecular cloning and sequencing confirmed that the new allele is identical to DQB1*0609 at exon 2 except for 3 nucleotide substitutions at positions 353, 356 and 367, also found in other alleles. These nucleotide changes may explain its anomalous reactivity.  相似文献   
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