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排序方式: 共有509条查询结果,搜索用时 15 毫秒
1.
Here we retrospectively examine the efficacy of two antibody induction regimens using Zenapax or Thymoglobulin in patients with positive complement-dependent cytotoxicity crossmatches (CDC-CMXs) desensitized with IVIG (intravenous immunoglobulin). Between January 1999 and March 2005, 97 patients with (+) CDC-CMXs received kidney transplants (43 deceased donors/54 living donors). All patients received at least 2 g/kg IVIG (maximum four doses) until an acceptable CMX was obtained. Patients were divided into two groups: 1. IVIG + Zenapax (n = 58), 2. IVIG + Thymoglobulin (n = 39). A total of 94% of patients in Group 1 and 84% in G2 have at least 2 years of follow up. Patient and graft survival was 96%/84% in Group 1 and 100%/90% in Group 2, p = NS. The number and severity of AR episodes were similar (36% Group 1 vs. 31% Group 2, p = NS) as was the incidence of C4d (+) antibody-mediated rejection (AMR) (Banff Grade II/III) (22% Group 1 vs. 21% Group 2). Mean serum creatinines (SCrs) at 24 months were similar (Group 1: 1.4 +/- 0.7 vs. G2: 1.5 +/- 0.7 mg/dL). Induction therapy with Zenapax or Thymoglobulin results in excellent patient, graft survival and graft function at 2 years. There was no increased risk of viral infections or malignancies with either agent. Neither agent was effective in reducing the incidence of AMR.  相似文献   
2.
The effects of concurrent graft-versus-host reaction (GvHR) on the course of Giardia infection in CBA x BALB/c F1 mice have been examined, to test the hypothesis that T-cell-mediated immunity, in the form of a local DTH reaction, alters the host-parasite relationship in favour of the host by changing the physical environment of the parasite. GvHR did not enhance immunity, indeed mice infected with Giardia at a late stage of GvHR had significantly higher faecal cyst excretion and prolongation of the plateau phase of infection, indicating a degree of immunodeficiency.  相似文献   
3.
本文应用植物血凝素(PHA)检测了乌市维汉族学龄儿童的细胞免疫功能。结果表明,汉族儿童的PHA红斑直径均值高于维族,不论维汉族男女生均以9~10岁年龄段PHA红斑均值最大,并有随年龄增加而下降的趋势。同时对缺铁性贫血、生长发育水平及营养状况对细胞免疫功能的影响进行了初步探讨。  相似文献   
4.
In vitro comparisons of induction of perforin (PFP), granzyme B (GRB), production of cytokines, and cell-mediated cytotoxicity by interleukin-2 (IL-2), interleukin-15 (IL-15), or combinational IL-2/IL-15-induced lymphokine-activated killer cells were studied in this study. Whereas IL-2-induction was associated with a decrease in cultured cell population over a 7-day period, IL-15 alone or in combination with IL-2 resulted in significant increase including cytotoxic T lymphocytes and subsets of CD56+ lymphocytes, particularly cytokine-induced killer and cytolytic natural killer-T lymphocytes. The overall PFP, GRB, and tumor necrosis factor-alpha expression in different subtypes were also significantly higher with IL-15 alone or in combination with IL-2 induction with resultant superior cytotoxicity compared to IL-2 treatment. There was no significant advantage of addition of IL-2 over IL-15 induction. These results offer further information on the cytotoxic potency of these cytokines and their mechanisms of action implicating potential use of IL-15 as part of cytokine adoptive immunotherapy.  相似文献   
5.
Lymphocyte transformation response of calves to respiratory syncytial virus   总被引:1,自引:0,他引:1  
Virus-specific cell-mediated immunity, as determined by in vitro lymphocyte transformation (LT), was demonstrated in calves following infection and vaccination with respiratory syncytial virus (RSV). After experimental infection, 4 of 6 gnotobiotic calves and 6 of 21 conventional calves developed a significant LT response to RSV. By means of a whole blood assay, the LT responses of calves were examined after vaccination with an inactivated vaccine, which consisted of glutaraldehyde-fixed bovine nasal mucosa cells persistently infected with a bovine strain of RSV (GC), a live modified bovine strain of RSV (MV), or a live temperature-sensitive mutant of a human strain of RSV (ts-l). Three weeks after vaccination, a virus-specific LT response was detected in 6 of 6 calves given the GC vaccine, 0 of 4 calves given the MV vaccine, and 2 of 4 calves given the ts-l vaccine. The magnitude of the response was greatest in those animals given the GC vaccine. There was no significant correlation between the magnitude of the LT response and levels of serum neutralising antibody. However, the LT response did correlate with serum antibody measured by the single radial haemolysis test 3 weeks after the first vaccination. LT activity to RSV was associated with T and not B lymphocytes. The development of a virus-specific LT response in calves given an inactivated RSV vaccine was not associated with an increase in respiratory disease following challenge with live virus, but rather was related to increased resistance to RSV infection.  相似文献   
6.
Three sets of cytotoxic effector cells were generated against the A1, B8, DR3 haplotype using haptoidentical individuals in three different families. The three sets of effector cells generated against this haplotype showed excellent reproducibility testing, strong cytotoxicity against their specific targets, low autologous kill, and segregation with the sensitizing haplotype within the family. When tested against a panel of cells bearing all combinations the A1, B8. DR3 antigens, a hierarchy of contribution of the individual HLA antigens as CML target determinants was seen. A new strong target cell determinant was identified by cytotoxicity with one of the effector cells not explicable in terms of the A1, B8, DR3 antigens or known HLA cross-reactivity. A family study demonstrated that this determinant clearly segregates with HLA. The success of this approach in defining new CML determinants may result from the generation of effector cells across a single haplotype in strong linkage disequilibrium or from the presentation of CML determinants in the context of self.  相似文献   
7.
Cell mediated lympholysis (CML) has been proposed as an in vitro model of the rejection process that results from transplantation of allogeneic tissue. To date, the absolute frequencies of cytotoxic T lymphocytes (CTL) and their precursors (CTL.P) have not been directly estimated in man because of technical difficulties. Through optimizing the conditions for radiometric detection of 51Cr release and the attendant improvement in CML sensitivity, direct CTL frequency estimates have been determined in peripheral blood (PBL), spleen (SPL), and lymph nodes (LNC) after in vitro allostimulation using unrelated human cells and limiting dilution assays. The mean frequency of CTL generated from PBL is 1 in 826 cells (0.121% +/- 0.101%) which, from preliminary experiments, is significantly greater than that generated from either LNC or SPL (p less than 0.05). With restimulation of primed cells on day 10, the frequency of CTL generated from PBL was increased 400%. The CTL.P frequency (0.0064% +/- 0.0050%) was approximately 5% of the corresponding CTL frequency. The CTL.P frequencies were found to be minimal estimates as both accessory "filler" cells and T cell growth factors increased the level of detection of CTL.P an average of threefold. The limiting cell dilution assay as detailed in this report should be a powerful tool for defining the cellular requirements and related factors necessary for optimal induction of a CTL response and should provide the means for determination of the immunogenetic requirements and the allospecificity of human cytotoxic lymphocytes.  相似文献   
8.
Interleukin-12 (IL-12) is a disulfide-linked heterodimeric cytokine originally identified as a product of EBV-transformed B cell lines. Monocyte/macrophages are the physiologically most relevant producers of IL-12, in response to both Gram-positive and -negative bacteria, bacterial products, and intracellular parasites. Although IL-12 has an enhancing effect on the survival and growth of early hematopoietic progenitor cells, most of the IL-12 biological activity has been described on T and NK cells, on which it induces production of lymphokines, primarily IFN-, enhances cytotoxic activity, and, in cooperation with other stimuli, increases proliferation. IL-12 is an inducer of development of T helper type 1 (Th-1) cells and the equilibrium between IL-12 and IL-4 is probably important for the balancein vivo between Th-1 and Th-2 responses. IL-12 has an important role in the host resistance to infection, in particular to intracellular pathogens, by activating macrophages through induction of IFN- from NK and T cells and by enhancing cell-mediated immune responses, dependent on Th-1 cell development. Peripheral blood mononuclear cells from HIV-seropositive individuals are impaired in their ability to produce IL-12 in response to bacterial stimulation, and IL-12 restoresin vitro some of the depressed immunological functions, suggesting that a defect in IL-12 production may have a pathogenic role in the immunodeficiency of HIV-infected individuals. Natural IL-12 appears to provide a regulatory link between innate resistance and the development of the antigen-specific adaptive immune response and the recombinant protein has therapeutic potential because of its activity against tumors and infections and its effectiveness as an adjuvant enhancing cell-mediated immunity in vaccination.  相似文献   
9.
目的探讨中草药抗糖尿病发病和降血糖的机制.方法将大白鼠分成5组,芪苓汤组、八味地黄丸组、柴苓汤组,分别接受相应药物治疗;模型组接受自来水治疗.各组从实验的 d 8 起腹腔内注射链脲霉素 30 mg*kg-1,每天1次,连续 5 d.另设正常对照组,不作任何处理.检测大白鼠的体重、血糖、果糖胺、胰岛素及T淋巴细胞(W3/25和OX8)的百分率,取胰腺组织作组织学检查.结果用药各组的糖尿病发病率比模型组低(P<0.05).d 26 八味地黄丸组和柴苓汤组的血糖分别比 d 15 下降25%和18%(P<0.05).芪苓汤组和八味地黄丸组的W3/25细胞比率明显高于对照组.用药各组的平均胰岛面积和平均β细胞面积较模型组大.结论八味地黄丸、柴苓汤方剂具有降血糖作用;3方剂不同程度降低糖尿病发病率可能与提高细胞免疫功能有关.  相似文献   
10.
Background and aim:?Sixty male Wistar rats, divided into 4 groups, 15 each, were designed as I-control rats, II-rats orally intubated with Nigella sativa oil (1?ml/kg b.wt./day) for 5 days/week, III-whole body gamma irradiated rats with the estimated LD50/30 (4 Gray) and IV-rats daily intubated with Nigella sativa oil then subjected to whole body gamma irradiation, to investigate the radioprotective potential of Nigella crude oil against hemopoietic adverse effects of gamma irradiation.

Results:?Irradiation resulted in significant reduction in hemolysin antibodies titers and delayed type hypersensitivity reaction of irradiated rats, in addition to significant leukopenia and significant decrease in plasma total protein and globulin concentrations and depletion of lymphoid follicles of spleen and thymus gland. Furthermore, there was a significant increase in malondialdehyde concentration with a significant decrease in plasma glutathione peroxidase, catalase and erythrocyte superoxide dismutase activities were recorded. Oral administration of Nigella sativa oil before irradiation considerably normalized all the above-mentioned criteria; and produced significant regeneration in spleen and thymus lymphoid follicles.

Conclusion:?Our results strongly recommend Nigella sativa oil as a promising natural radioprotective agent against immunosuppressive and oxidative effects of ionizing radiation.  相似文献   
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