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Background II has hecn well documented that environmental factors such as antigenpresenting cells and related cytokines could affect the development of T helper cells. Objective The purpose of this study is to investigate the effect of different adjuvants on T cell development. Methods Ovalbumin (OVA) combined with aluminum hydroxide (Alum) plus pertussis toxin (PT) or complete Freund's adjuvant (CFA) were used to sensitize mice; the production of IgG and IgE anli-OVA antibodies was then followed. In addition, OVA-specific proliferative responses and cytokine production by spleen cells were also investigated. Results The data showed that the adjuvants themselves could modify the pattern of immune response: (1) IgG2a > anti-OVA antibody was higher in mice sensitized with OVA + CFA compared to that of mice sensitized with OVA + Alum + PT; (2) the ratio of IFN-γ/IL-4 produced by OVA-stimutated spleen cells was higher in mice sensitized with OVA + CFA than that of mice sensitized with OVA + Alum + PT; (3) increased percentage of γδ T cells was noted in the peritoneal exudate cells of OVA + CFA immunized mice; and (4) the immune response of mice sensitized wilh OVA + Alum+ PT was inhibited by the adoptively transferred ascitic cells from OVA + CFA immunized mice. Conclusion In general, the data suggested higher IgG2a and the ratio of IFN-γ/IL-4 was noted In mice sensitized with OVA + CFA. Further elucidation of the regulatory mechanism of allergen-specific T helper cells development and exploration of possible agents for inmiunotherapy might shed light on the management of atopic diseases.  相似文献   
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用国产Na~(125)I源、氯胺-T法、制备(-)~(125)I心得静标记配体【(-)~(125)I-IPIN】,放射色谱法分离复合物,测得(-)_(125)I-IPIN的Rf值为0.35,比活度为46.12~55.32TBq/mmol,标记率为37%,放射化学纯度达95%以上,该标记配体与小鼠脑细胞膜β受体的结合用受体的放射配体结合分析法(RBA)考核,呈典型的饱和曲线,Scatchard分析呈一直线,平衡解离常数(Kd)为0.041±0.001nM,Hill系数接近于1(0.99)。  相似文献   
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Q—T间期延长对急性心肌梗死预后的估价   总被引:1,自引:0,他引:1  
近来,对Q—T间期在心肌梗死中变化的意义愈来愈受到重视。恶性室性心律失常或摔死被认为与Q—TIN期的变化有关、本文将对27例急性心肌梗死病例进行回顾性分析.提示Q—TIW期延长是影响心肌梗死病人预后的重要因素之一。llta床资料1.l一般资料。取自我院收治的27例急性心肌梗死(AMI)病历。其中男20例,女7例。年龄分布40~84岁,其中40岁~50岁6例,sl岁~60岁9例,61岁~70岁10例,71岁以上者2例。1.2方法。测量所有心电图的Q—T间期变化.排除心率、年龄、性别及药物对Q—T间期的影响。根据D。rshazi及Cinca标准,测量AMI敏…  相似文献   
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史艳侠  张晓实  刘冬耕  管忠震  姜文奇 《癌症》2004,23(Z1):1437-1442
背景及目的:目前认为B细胞非霍奇金淋巴瘤(B-NHL)常伴随免疫抑制,CD8 CD28-Ts(Ts)细胞和CD3 CD56 NKT(NKT)是新鉴定的新型免疫抑制性调节细胞,在肿瘤的免疫抑制及免疫逃逸机制中起重要作用,但它们在B细胞淋巴瘤患者外周血的分布情况及其免疫抑制中的作用目前尚不清楚。本文通过分析两者在化疗前及化疗后B-NHL患者外周血中比例及变化规律,初步探讨它们在B-NHL的免疫抑制作用及其影响因素,为有效干预患者的免疫功能提供参考。方法:应用流式细胞仪检测79例治疗前的B-NHL患者、经4~6周期化疗后完全缓解(CR)的18例患者、30例健康志愿者外周静脉血中NKT及Ts细胞的比例。结果:在79例治疗前B-NHL患者的外周血中,Ts细胞比例为(18.19±5.03)%,较正常对照组(11.20±3.49)%明显增高(P<0.01);NKT的比例为(6.08±3.29)%,亦较正常对照组的(3.52±1.56)%明显增高(P<0.01)。Ts在不同临床分期的患者之间无显著性差异P>0.05;Ⅰ期为(17.56±4.10)%、Ⅱ期为(18.05±5.64)%、Ⅲ期为(18.14±5.58)%、Ⅳ期为(18.95±4.64)%;在不同恶性程度的患者之间亦无显著性差异P>0.05;低度恶性为(17.81±5.24)%、中度恶性为(18.37±4.83)%、高度恶性为(18.31±5.93)%;在治疗前(18.64±4.55)%和CR后(19.42±4.95)%患者之间亦无显著性差异(P=0  相似文献   
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Background: It has been suggested that routine assessment and quantification of different lymphocyte subsets can provide clinically meaningful prognostic information in breast cancer (BC). Objective: To determine the relationship between peripheral blood lymphocyte subsets and pathological parameters and response to therapy in patients with BC. Methods: Thirty patients with operable breast cancer treated surgically with either modified radical mastectomy or breast conservative surgery, and 20 healthy controls were included. For detection of lymphocyte subsets in peripheral blood; Fluorochrome-labeled monoclonal antibodies were used and cells were analyzed by flow cytometry. Patients were treated with chemotherapy, radiotherapy and hormonal treatment, and followed up to determine relapse and recurrence-free survival (RFS). Results: Significant differences were found in the frequencies of B, T, NK, NKT, and CD28‒T cells between patients with BC and controls. Moreover, a significant difference was found in the percentage of CD8+CD28‒ T cells between patients with different pathologic subtypes of BC and negative correlations were observed between the frequency of CD8+CD28‒T cells and memory B cells, and RFS. Also, a significant difference in the frequency of naïve B cells was found in patients with different tumor grades and a negative correlation was found between the frequencies of B cells and NKT cells. Conclusion: NK, NKT, lymphocytes, and CD28‒ T cells significantly differed between healthy controls and BC patients. Also, memory B cells were associated with good response to treatment while CD28‒ T cells were associated with shorter RFS.  相似文献   
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The article presents the results of the analysis of the interactions between the single point incremental forming (SPIF) process parameters and the main roughness parameters of stiffened ribs fabricated in Alclad aluminium alloy panels. EN AW-7075-T6 and EN AW-2024-T3 Alclad aluminium alloy sheets were used as the research material. Panels with longitudinal ribs were produced with different values of incremental vertical step size and tool rotational speed. Alclad is formed of high-purity aluminium surface layers metallurgically bonded to aluminium alloy core material. The quality of the surface roughness and unbroken Alclad are key problems in SPIF of Alclad sheets destined for aerospace applications. The interactions between the SPIF process parameters and the main roughness parameters of the stiffened ribs were determined. The influence of forming parameters on average roughness Sa and the 10-point peak–valley surface roughness Sz was determined using artificial neural networks. The greater the value of the incremental vertical step size, the more prominent the ridges found in the inner surface of stiffened ribs, especially in the case of both Alclad aluminium alloy sheets. The predictive models of ANNs for the Sa and the Sz were characterised by performance measures with R2 values lying between 0.657 and 0.979. A different character of change in surface roughness was found for sheets covered with and not covered with a soft layer of technically pure aluminium. In the case of Alclad sheets, increasing the value of the incremental vertical step size increases the value of the surface roughness parameters Sa and Sz. In the case of the sheets not covered by Alclad, reduction of the tool rotational speed increases the Sz parameter and decreases the Sa parameter. An obvious increase in the Sz parameter was observed with an increase in the incremental vertical step size.  相似文献   
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