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1.
Alcoholics admitted to the hospital solely for detoxication have been studied by flow cytometry to evaluate changes in the surface markers of peripheral blood leukocytes. As we have shown previously, such patients have an elevated percentage of CD8hl lymphocytes that are HLA DR+; we now demonstrate that they also have striking alterations in the quantitative relationships of the fine T-cell subsets. Both CD4+ and CD8hl lymphocytes have a sharply reduced percentage of the l -selectin+ CD45RA+ subset, increased percentages of the CD45RA-subsets, and several other fine subset alterations. The fine subset profile suggests, according to current correlations of phenotype and function, that both CD4+ suppressor inducer and CD4-dependent CD8+ suppressor effector cells are reduced, whereas other subsets, including CD8+ CTL or their precursors, are increased in relative percentages. Some of the phenotypic changes are reversible over the several days following withdrawal. In other results, the percentage of CD8hl lymphocytes expressing CD11b (β-integrin) is shown to be reciprocal with the percentage expressing l -selectin both in normals and alcoholics. However, the regression function of CD11b vs. l -selectin on CD8hl cells is different for the alcoholics than for the normals, indicating an abnormality in the regulation of the expression of these two adhesion markers. Taken together, this abnormality of adhesion molecules and the fine subset alterations previously described indicate widespread changes in the peripheral lymphocytes of currently drinking alcoholics. These changes suggest functional deficiencies that may include alterations of lymphocyte traffic and other adhesion-dependent functions, and a shift in the balance of regulatory interactions.  相似文献   
2.
Alcoholic patients often have impaired immune function, yet little is known about the precise mechanism(s) of this impairment. We have previously shown that ethanol consumption by mice alters copolymer-specific humoral and cellular immune responses. In this study, we asked whether alcohol consumption by mice would phenotypically alter lymphocyte populations. Female C57BL/6 mice were fed a nutritionally complete liquid diet containing 35% ethanol-derived calories for up to 8 days. As controls, mice either were fed a liquid control diet that isocalorically substitutes sucrose for ethanol or remained on a standard solid diet and water ad libitum. Although mice fed ethanol-containing liquid or pair-fed control liquid diets have decreased numbers of spleen cells compared with solid diet controls, only the ethanol-containing diet allowed normally nonresponder C57BL/6 spleen cells to make antibody responses to the poly(Glu50Tyr50) synthetic copolymer antigen. Flow cytometric analysis of splenic lymphocyte populations of mice on the ethanol-containing diet shows an increase in the relative proportion of T-lymphocytes as compared with mice on either solid or liquid control diets. No such change is seen for either B-cell or natural killer cell populations in these same mice. Both liquid control and liquid ethanol diets caused a slight decrease in the CD4:CD8 ratios of splenic T-lymphocytes. We see the relative percentage of T-cells bearing the αβ-cell receptor (TcR) increases in the spleens of liquid ethanol diet mice; a smaller increase TcRαβ usage is seen in the spleens of liquid control mice, compared with solid diet mice. Flow cytometric analysis shows that little, if any, difference exists in TcRγδ expression between the liquid ethanol and either the liquid control or solid diet groups. Preliminary analysis of TcRαβ subsets suggest that ethanol increases the percentage of T-cells expressing Vβ5 and Vβ8, and decreases the percentage of Vβ11 expressing cells. These findings suggest that, in addition to modifying the immune response, ethanol alters the phenotypic expression of lymphocyte subsets.  相似文献   
3.
本文用体外实验方法,研究BCG-PSN对TL-CFu形成及IL-2R表达的调节作用。结果表明,当BCG-PSN浓度为80μg/ml时,TL-CFU形成及IL-2R表达均达到峰值,对IL-2R表达的调节于72h达最高水平,并且.TL-CFU形成和IL-2R表达均显著高于对照组。提示BCG-PSN能增进T淋巴细胞功能。  相似文献   
4.
Summary A hypothesis is forwarded regarding the role of secondary spindle afferents and the FRA (flexor reflex afferents) in motor control. The hypothesis is based on evidence (cf. Lundberg et al. 1987a, b) summarized in 9 introductory paragraphs. Group II excitation. It is postulated that subsets of excitatory group II interneurones (transmitting disynaptic group II excitation to motoneurones) may be used by the brain to mediate motor commands. It is assumed that the brain selects subsets of interneurones with convergence of secondary afferents from muscles whose activity is required for the movement. During movements depending on coactivation of static -motoneurones impulses in secondary afferents may servo-control transmission to -motoneurones at an interneuronal level. The large group II unitary EPSPs in interneurones are taken to indicate that, given an adequate interneuronal excitability, impulses in single secondary afferents may fire the interneurone and produce EPSPs in motoneurones; interneuronal transmission would then be equivalent to that in a monosynaptic pathway but with impulses from different muscles combining into one line. It is postulated that impulses in the FRA are evoked by the active movements and that the role of the multisensory convergence from the FRA onto the group II interneurones is to provide the high background excitability which allows the secondary spindle afferents to operate as outlined above. The working hypothesis is put forward that a movement governed by the excitatory group II interneurones is initiated by descending activation of these interneurones, but is maintained in a later phase by the combined effect of FRA activity evoked by the movement and by spindle secondaries activated by descending activation of static -motoneurones. As in the original follow up length servo hypothesis (Rossi 1927; Merton 1953), we assume that a movement at least in a certain phase can be governed from the brain solely or mainly via static -motoneurones. However, our hypothesis implies that the excitatory group II reflex connexions have a strength which does not allow transmission to motoneurones at rest and that the increase in the gain of transmission during an active movement is supplied by the movement itself. Group II inhibition. It is suggested that the inhibitory reflex pathways like the excitatory ones have subsets of interneurones with limited group II convergence. When higher centres utilize a subset of excitatory group II interneurones to evoke a given movement, they may mobilize inhibitory subsets to inhibit muscles not required in the movement. Inhibition may be reciprocal of extensors during flexor activation (the spinal pattern), of flexors during extensor activation or of flexors and extensors in more complex movements involving cocontraction of other flexors and extensors. It is postulated that group II inhibition depends on conjoint activation from spindle afferents and other sources (descending and/or the FRA) so that inhibition may be coupled to group II excitation of other motoneurones. Such a coupling would correspond to the --linkage in reciprocal Ia inhibition (Lundberg 1970) and is denoted --linkage in lateral group II inhibition. FRA and other reflex pathways. Results are summarized showing that the FRA evoke convergent excitation in interneurones not only in group II reflex pathways but also in other reflex pathways like the reciprocal Ia inhibitory, the nonreciprocal group I inhibitory and probably also in specialized reflex pathways from cutaneous afferents. It is inferred that facilitation of reflex transmission by impulses in the FRA evoked by the active movement may be a general principle. In this way reflex transmission to -motoneurones may be weak at rest and not disturb passive movements but have a high gain when the reflexes are required to regulate active movement.This work was supported by the Swedish Medical Research Council (project no. 94)  相似文献   
5.
乙型肝炎的T淋巴细胞亚群的演变规律   总被引:1,自引:0,他引:1  
目的:了解不同类型乙型肝炎患者T淋巴细胞亚群的演变规律及意义。方法:我院2002年7月~2004年6月收治的16例急性肝炎、40例慢性肝炎及46例重型肝炎病例的抗凝血,通过流式细胞仪检测其T淋巴细胞亚群,对不同类型肝炎进行统计学分析。结果:慢性肝炎组与急性肝炎组比较CD3 ,CD8 细胞计数降低且差异有显著性(P<0.05)。重型肝炎组与非重型肝炎组(急性肝炎组与慢性肝炎组)比较CD3 ,CD4 ,CD8 细胞计数明显降低(P<0.05),幼稚的CD4 ,CD8 细胞计数明显升高(P<0.05)。结论:不同类型乙型肝炎的T淋巴细胞亚群有明显差异,乙型肝炎随着病情严重及病程延长,CD3 ,CD4 ,CD8 淋巴细胞逐渐减少,重型肝炎出现大量幼稚的CD4 CD8 淋巴细胞,T淋巴细胞亚群的变化可以反映病情严重程度及免疫状态,对免疫调节治疗有指导意义。  相似文献   
6.
针药复合麻醉对肿瘤患者围手术期功能状态的影响   总被引:2,自引:3,他引:2  
顾陈怿  胡军  蔡云彪 《中国针灸》2004,24(4):257-259
目的:探讨针药复合麻醉对肿瘤患者围手术期免疫功能和血液动力学的影响.方法:将22例择期腹部肿瘤手术患者,随机分为全身麻醉组(A组)、针药复合全身麻醉组(B组),分别于麻醉前、术后、术后第2天及第5天测定 T淋巴细胞亚群值,并监测平均动脉压和心率的变化.结果:针药复合麻醉可以减轻肿瘤患者围手术期细胞免疫功能抑制的程度,并且对维持围手术期血流动力学的平稳也起一定作用.结论:针药复合全麻是一种可供临床选择运用的良好麻醉方法.  相似文献   
7.
Background: Host effector mechanism against Mycobacterium tuberculosis (Mtb) infection is dependent on innate immune response by macrophages and neutrophils and the alterations in balanced adaptive immunity. Coordinated release of cytolytic effector molecules from NK cells and effector T cells and the subsequent granule-associated killing of infected cells have been documented; however, their role in clinical tuberculosis (TB) is still controversy.Objective: To investigate whether circulating granulysin and other effector molecules are associated with the number of NK cells, iNKT cells, Vγ9+Vδ2+ T cells, CD4+ T cells and CD8+ T cells, and such association influences the clinical outcome of the disease in patients with pulmonary TB and HIV/TB coinfection.Methods: Circulating granulysin, perforin, granzyme-B and IFN-γ levels were determined by ELISA. The isoforms of granulysin were analyzed by Western blot analysis. The effector cells were analyzed by flow cytometry.Results: Circulating granulysin and perforin levels in TB patients were lower than healthy controls, whereas the granulysin levels in HIV/TB coinfection were much higher than in any other groups, TB and HIV with or without receiving HAART, which corresponded to the number of CD8+ T cells which kept high, but not with NK cells and other possible cellular sources of granulysin. In addition, the 17kDa, 15kDa and 9kDa isoforms of granulysin were recognized in plasma of HIV/TB coinfection. Increased granulysin and decreased IFN-γ levels in HIV/TB coinfection and TB after completion of anti-TB therapy were observed.Conclusion: The results suggested that the alteration of circulating granulysin has potential function in host immune response against TB and HIV/TB coinfection. This is the first demonstration so far of granulysin in HIV/TB coinfection.  相似文献   
8.
目的分析卵巢癌患者外周血T淋巴细胞亚群、免疫球蛋白的变化,监测卵巢癌患者的免疫功能水平。方法用流式细胞仪测定45例卵巢癌患者、35例卵巢良性肿瘤患者和30名健康对照组的外周血T淋巴细胞亚群,采用免疫比浊法测定3组样本血清Ig A、Ig G、Ig M含量。结果卵巢癌患者全血CD8+明显高于健康对照组(P<0.05),而血CD4+及CD4+/CD8+比值则显著低于健康对照组(P<0.05)。Ig G、Ig M水平均高于对照组(P<0.05),而Ig A水平两组无显著差异(P>0.05)。外周血T淋巴细胞亚群和免疫球蛋白的改变与卵巢癌病理分期有关,分期越晚,CD4+及CD4+/CD8+比值越低,CD8+、Ig G、Ig M水平越高,Ⅱ期与Ⅲ期、Ⅳ期之间有显著性差异(P<0.05)。结论卵巢癌患者细胞免疫功能降低,体液免疫功能增强。外周血T细胞亚群和免疫球蛋白的检测对判断卵巢癌患者的病情、预后以及机体的免疫功能的判断有一定意义。  相似文献   
9.
目的探讨恩替卡韦分散片(ETV)治疗对高病毒载量慢性乙肝患者的T细胞亚群及血清脂联素(ADP)、干扰素-γ(IFN-γ)、白细胞介素-2(IL-2)水平的影响。方法从本院于2018年6月至2020年6月收治慢性乙肝患者中筛选经荧光定量PCR法测定HBV-DNA>2×105 IU/mL为高病毒载量86例进行研究,按随机数字表法分对照组和观察组,予以对照组常规减黄、保肝及营养支持等对症治疗,观察组在对症治疗基础上予以ETV治疗,均持续治疗6个月,比较两组T细胞亚群、病毒载量指标及Th1/Th2型与相关炎性因子水平。结果经治疗,两组CD3+、CD4+水平均见提升,CD8+水平有一定下降,观察组CD3+、CD4+水平较对照组更高,CD8+水平则更低(P<0.05);两组HBsAg、HBeAg及HBV-DNA载量水平均见相应降低,观察组低于对照组(P<0.05);两组ADP水平呈上升趋势,IFN-γ及IL-2水平均呈下降趋势,观察组ADP水平高于对照组,IFN-γ及IL-2水平均更低(P<0.05)。结论高病毒载量慢性乙肝患者应用恩替卡韦分散片治疗,有助于T细胞亚群改善,且较大程度降低了病毒载量水平,并增强了机体免疫功能。  相似文献   
10.
Integration of cellular and humoral arms of the innate immune response is fundamental to the development of powerful effector functions in host defence as well as aberrant immune responses. Here, we provide evidence in support of the relationship between complement activation and NK cell functional modulation. We demonstrate that human NK cells and both CD56brightCD16 and CD56dimCD16+ populations express receptors known to detect the biologically active peptides C3a and C5a (i.e. C3aR, C5aR, C5L2) and the covalently-bound fragments C3b and metabolites iC3b and C3d which serve in immune adhesion (e.g. CR3, CR4). We also show that several pathogen- or tumour/inflammation-related stimuli differentially regulated those complement receptor expression. Furthermore, our results suggest that C3 fragments (C3a, iC3b) have a negative regulatory effect on IFN-γ production in NK cells. This work provides extensive information of human complement receptors relevant to the integrated actions of complement and NK cells which has been suggested by animal studies. The observations may act as a resource that allows further understanding and exploitation of role of complement in human health and immune mediated diseases.  相似文献   
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