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We have successfully cloned nine NKR-P1+ TCR alpha beta + cells from PVG rat spleens, utilizing murine macrophage inflammatory protein-1 alpha (MIP-1 alpha) and IL-2. These clones are either double negative (DN, CD4-CD8-), which included clones 3.31, 3.71, 4.19, 4.59 and 4.65, or single positive (SP, CD4+CD8-), which included clones 1.64, 3.8, 3.76 and 3.78. No CD8+ clone was recovered. All nine clones are restricted in terms of their expression of the V beta antigens, since they express V beta 8.2 but not V beta 8.5, V beta 10 or V beta 16. These clones are agranular and they fall to generate NK or LAK activity upon incubation with IL-2, IL-12 or their combination. On the basis of their production of intracellular cytokines they can be divided into three categories: (I) SP clones (1.64, 3.8, 3.76 and 3.78) do not produce IL-2 or IL-4, but produce IFN-gamma and IL-12, and they vary in their production of IL-1, RANTES or tumor necrosis factor (TNF)-alpha; (II) DN clones 4.59 and 4.65 produce IL-1 alpha and IFN-gamma only, and fall to produce other cytokines; and (III) DN clones 3.31, 3.71 and 4.19 produce IL-1 alpha, IL-1 beta, IL-2, IL-12, IFN-gamma, RANTES and TNF-alpha. From all the clones examined only DN clones 3.31 and to a lesser degree 4.19 produce IL-4. In vivo tissue localization of clones 3.8, 3.31 and 4.59 shows that these cells distribute into the liver and bone marrow 24 h post i.v. administration. Their accumulation in the liver and bone marrow along with their ability to secrete various cytokines suggest that these cells may influence the generation, differentiation or apoptosis of immune or hematopoietic cells.   相似文献   
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A substudy of a phase I/II, prospective, multicenter clinical trial was carried out to investigate the potential benefit of therapeutic vaccination on hepatitis B e antigen-negative patients with chronic hepatitis B (CHB), treated efficiently with analogues. Patients were randomized in 2 arms, one receiving a hepatitis B virus (HBV) envelope DNA vaccine, and one without vaccination. At baseline, HBV-specific interferon (IFN)-γ–producing T cells were detected in both groups after in vitro expansion of peripheral blood mononuclear cells. Vaccine-specific responses remained stable in the vaccine group, whereas in the control group the percentage of patients with HBV-specific IFN-γ–producing T cells decreased over time. The vaccine-specific cytokine-producing T cells were mostly polyfunctional CD4+ T cells, and the proportion of triple cytokine-producer T cells was boosted after DNA injections. However, these T-cell responses did not impact on HBV reactivation after stopping analogue treatment. Importantly, before cessation of treatment serum hepatitis B surface antigen (HBsAg) titers were significantly associated with DNA or HBsAg clearance. Therapeutic vaccination in CHB patients with persistent suppression of HBV replication led to the persistence of T-cell responses, but further improvements should be searched for to control infection after treatment discontinuation.  相似文献   
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用[3H]TdR参入法检测小鼠脾细胞增殖能力及产生集落刺激因子(colony stimulating factor. CSF)含量.证明商陆多糖Ⅱ(PAP-Ⅱ)在31~500 μg·m-1范围内显著促进小鼠稗细胞增殖。PAP-Ⅱ,31~125 μg·ml-1可剂量依赖性地促进Con A(1,2.8μg·ml-1),LPS(3,10,30 μg·ml-1)诱导的淋巴细胞细咆增殖,随着PAP-Ⅱ剂量加大,对丝裂原诱导的淋巴细胞增殖反呈抑制作用。PAP-Ⅱ。10~500μg·ml-1呈剂量及时间依赖性地促进脾细胞产生CSF,其最适剂量为100 μg·ml-1。最佳时间为5 d,提示PAP-Ⅱ能增强免疫及促进造血功能。  相似文献   
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以培养血管平滑肌细胞(vascularsmcothmusclecell,VSMC)为模型,观察了间硝苯地平(m-nifedipine,m-Nif)对血管紧张素Ⅱ(angiotensinⅡ,ANGⅡ)促进VSMC增殖和蛋白质合成的影响。结果表明,m-Nif抑制ANGⅡ(100nmol·L ̄(-1))引起VSMC[ ̄3H]thymidine和[ ̄3H]leucine参入,并呈剂量依赖性。m-Nif(2×10 ̄(-6)mol·L ̄(-1))可抑制ANGⅡ对VSMC的刺激、DNA及蛋白质合成速率,分别降低了46%,58%,53%。提示m-Nif可抑制ANGⅡ对VSMC增殖和蛋白合成的促进作用  相似文献   
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J E Macintosh  N Bogduk 《Spine》1987,12(7):658-668
The lumbar erector spinae consists of two muscles--iliocostalis lumborum and longissimus thoracis--each with distinct thoracic and lumbar parts. The thoracic parts consist of tiny muscle bellies with segmental origins from the thorax and long caudal tendons that form the erector spinae aponeurosis. The lumbar fibers arise from the lumbar accessory processes and the L1-4 transverse processes, and insert independently of the erector spinae aponeurosis into the ilium. The intrinsic lumbar fibers of the erector spinae are poorly described in the literature, and the existence of the iliocostalis lumborum pars lumborum has rarely been recognized even though it constitutes a substantial portion of the total muscle mass acting directly on the lumbar vertebrae.  相似文献   
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