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1.
驱虫斑鸠菊注射液对小鼠免疫功能的影响   总被引:4,自引:0,他引:4  
目的:探讨驱虫斑鸠菊对小鼠免疫功能的影响。方法:采用[3H]-TdR掺入法和脾细胞介导羊红细胞定量溶血分光光度法以及迟发型超敏反应试验等观察了驱虫斑鸠菊对小鼠兔疫功能的作用。结果:驱虫斑鸠菊在体内外均可以明显抑制ConA刺激的小鼠T淋巴细胞的增殖反应和LPS刺激的小鼠B淋巴细胞的增殖反应(P<0.01);对小鼠胸腺指数和脾脏指数、绵羊红细胞(SRBC)诱导的正常小鼠脾抗体细胞生成反应以及小鼠皮肤迟发型超敏反应都显示出明显的抑制作用,而且上述抑制作用与药物浓度有一定的剂量效应关系。结论:驱虫斑鸠菊对机体体液免疫、细胞免疫都有明显的抑制作用。  相似文献   
2.
D.S. Linthicum 《Immunobiology》1982,162(3):211-220
The development of acute experimental autoimmune encephalomyelitis (EAE) in mice is potentiated by the use of Bordetella pertussis vaccine as an adjuvant. Histamine sensitizing factor (HSF) extracted from B. pertussis is the active adjuvant agent and causes a mild increase in cerebrovascular permeability. During the development of EAE, there is an additional increase in vascular permeability of the brain and spinal cord. The adjuvant action of B. pertussis HSF does not appear to mimic a generalized beta-adrenergic blockade, since the course of EAE is not potentiated by adrenalectomy. The cerebrovascular permeability changes observed in EAE are probably mediated by vasoactive amines, since the expression of EAE can be blocked by vasoactive amine antagonists.  相似文献   
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We have determined cutaneous DTH reactions to SK-SD and PPD and peripheral blood lymphocyte profiles in a group of asbestos workers in two consecutive surveys. It was found that asbestosis and, to a lesser extent, the presence of ANA are significantly correlated with the lack of response to the above antigens. 83% of asbestos workers when tested at a 4 year interval fell into the same two categories of responsiveness (lack of response or response at least to one antigen).The asbestosis cases had lower total lymphocyte count as well as proportions and absolute number of E-RFC as compared to asbestos workers without asbestosis and/or ANA. Furthermore, the latter group showed the lower percentages and absolute number of E-RFC than the matched controls. The presence of ANA is also correlated with lower proportions of E-RFC. However, this is related at least in part to asbestosis.  相似文献   
5.
We studied late graft rejection in a patient who had received a kidney transplant 9–10 years earlier from his mother and who had been off all immunosuppressive drugs for 7 years at the time of graft rejection onset. The mother differed for one HLA-A (A3) and one HLA-B (B62) antigen but had only a subtype mismatch at the HLA-DRβ1 locus (donor: DRβ1*1104; recipient: DRβ1*1102). A gradual rise in serum creatinine from 1.8 to 2.0 mg/dl at year 9 prompted a biopsy, which was negative for rejection (focal infiltrates but no tubulitis). Ten months later the patient’s creatinine had risen to > 3.4 mg/dl, and a second biopsy revealed extensive tubulitis, cellular rejection, and glomerular sclerosis. Sonicates of donor leukocytes triggered no delayed-type hypersensitivity (DTH) response above background (PBMC only) in the patient’s peripheral blood leukocytes obtained prior to year 9. A gradual recovery of antidonor DTH response between year 9 and 10 closely paralleled the change from tolerant to rejection status. Antidonor antibody was also undetectable in serum prior to year 9, but a donor-reactive antibody did develop at year 10.2 shortly after the peak of DTH response. The serum level of soluble donor HLA class I B62 antigen rose > 10-fold over prerejection level at the time of the biopsy-proven rejection, suggesting a possible trigger for both the cellular and humoral immune response. Nonetheless, we found no evidence for the de-velopment of humoral or cellular immunity to maternal HLA class I. Instead, DTH analysis of memory T cells of the patient obtained after rejection showed that a single maternal HLA DRβ1*1104 allopeptide, differing by two amino acids in sequence from the peptide of the recipient (DRβ1*1102), stimulated a strong memory DTH response. Similarly, we found an anti-HLA class II donor-specific antibody in serum that appeared to be crossreactive with DRβ1*1104 and DRβ1*1101 but not with the recipient DRβ1*1102 antigen. The data support the idea of a profound unresponsive state at both the cellular (DTH) and humoral level toward maternal HLA class I antigens that was not reversed even during late cellular rejection, despite the release of high levels of soluble HLA class I. Furthermore, the data suggest that DTH recovery was a close correlate of the onset of rejection and this “indirect” alloresponse, like the anti-donor alloantibody response that followed, was directed not to noninherited maternal HLA-A,B antigens but to the maternal HLA DRβ1*1104 subtype.  相似文献   
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Five T cell clones and two lines were derived from the lymph nodes (LN) of C57BL/6 mice immunized with radiation-attenuated lung-stage larvae of Schistosoma mansoni. All seven clones/lines were CD4+, CD8- and expressed high levels of CD44 and CD45RB surface markers. After prolonged maintenance in-vitro, with soluble antigen from 18 h schistosomula (SSP), five retained the ability to proliferate readily and release IFNg in response to conca-navalin A (Con-A) and to SSP and/or soluble adult worm antigen (SWAP). These Th clones/lines induced significant footpad DTH reactions when injected with SWAP, but were unable to confer protective immunity after transfer to naïve recipient mice. This result could be explained by the antigen specificity of the clones/lines, since they were not able to release IFNg when cultured in-vitro with living lung-stage larvae. A second possibility is that the high level of CD45RB expression, which is not seen on the surface of pulmonary CD4+ memory/effector cells isolated directly from protectively-vaccinated mice, alters the ability of the clones/lines to release IFNg and to induce a DTH response in the lungs when they encounter antigen released from migrating schistosomula.  相似文献   
8.
Components of high molecular-weight (PI) obtained from Ascaris suum extract down-regulate the Th1/Th2-related immune responses induced by ovalbumin (OVA)-immunization in mice. Furthermore, the PI down-modulates the ability of dendritic cells (DCs) to activate T lymphocytes by an IL-10-mediated mechanism. Here, we evaluated the role of toll like receptors 2 and 4 (TLR2 and 4) in the modulatory effect of PI on OVA-specific immune response and the PI interference on DC full activation. An inhibition of OVA-specific cellular and humoral responses were observed in wild type (WT) or in deficient in TLR2 (TLR2−/−) or 4 (TLR4−/−) mice immunized with OVA plus PI when compared with OVA-immunized mice. Low expression of class II MHC, CD40, CD80 and CD86 molecules was observed in lymph node (LN) cells from WT, TLR2−/− or TLR4−/− mice immunized with OVA plus PI compared with OVA-primed cells. We also verified that PI was able to modulate the activation of DCs derived from bone marrow of WT, TLR2−/− or TLR4−/− mice induced in vitro by agonists of TLRs, as observed by a decreased expression of class II MHC and costimulatory molecules and by low secretion of pro-inflammatory cytokines. Its effect was accompanied by IL-10 synthesis. In this sense, the modulatory effect of PI on specific-immune response and DC activation is independent of TLR2 or TLR4.  相似文献   
9.
This study explores the role of ovarian hormones in the phenotypic shaping of peripheral T-cell pool over the reproductive lifespan of rats. For this purpose, 2-month-old prepubertally ovariectomised (Ox) rats, showing oestrogen and progesterone deficiency, and 11-month-old Ox rats, exhibiting only progesterone deficiency, were examined for thymus output, and cellularity and composition of major TCRαβ+ peripheral blood lymphocyte (PBL) and splenocyte subsets. Although ovariectomy increased thymic output in both 2- and 11-month-old rats, the count of both CD4+ and CD8+ PBLs and splenocytes increased only in the former. In the blood and spleen of 11-month-old Ox rats only the count of CD8+ cells increased. Although ovariectomy affected the total CD4+ count in none of the examined compartments from the 11-month-old rats, it increased CD4+FoxP3+ PBL and splenocyte relative proportions over those in the age-matched controls. The age-related differences in the cellularity and the major subset composition in Ox rats were linked to the differences in the ovarian steroid hormone levels registered in 2- and 11-month-old rats. The administration of progesterone to Ox rats during the seven days before the sacrificing confirmed contribution of this hormone deficiency to the ovariectomy-induced changes in the TCRαβ+ PBL and splenocyte pool from 11-month-old rats. The expansion of the CD8+ splenocyte subset in the 11-month-old Ox rats reflected increases in cellularity of memory and, particularly, naïve cells. This was due to greater thymic output of CD8+ cells and homeostatic proliferation than apoptosis in 11-month-old Ox rats when compared with age-matched sham-Ox control rats. The homeostatic changes within CD8+ splenocyte pool from 11-month-old Ox rats, most likely, reflected the enhanced splenic IL-7 and TGF-β mRNA expression. Overall, in adult female rats, circulating oestrogen and progesterone provide maintenance of T-cell counts, a diversity of T-cell repertoire, and the main T-cell subset composition in the periphery. Progesterone deficiency affects mainly the CD8+ lymphocyte compartment through increasing thymic CD8+ cell export and upsetting homeostatic regulation within the CD8+ splenocyte pool. These alterations were reversible through progesterone supplementation.  相似文献   
10.
目的 了解结核分支杆菌重组抗原ESAT6 (E)、MPT64 (M)、Ag85A(A)及两两混合物诱发豚鼠产生迟发型超敏 (DTH)反应的能力。方法 常规皮肤实验法 :灭活H37Rv全菌体致敏豚鼠,皮肤试验以生理盐水为阴性对照,5UPPD标准品为阳性对照,0.8μgE、0.8μgM、0.8μgA、0.4μgA+0.4μgM、0.4μgA+0.4μgE、0.4μgE+0.4μgM分别于背部皮内注射,注射后24、48、72h分别测量硬结反应横、纵直径 (mm),取二者的平均值。皮肤试验轮圈法 :生理盐水、5UPPD及0.8μgE、0.8μgM、0.8μgA、0.4μgA+0.4μgM、0.4μgA+0.4μgE、0.4μgE+0.4μgM,以轮圈法注射于同一只豚鼠背部两侧,每批6只,共3批。注射后24、48、72h分别测量硬结反应横、纵直径 (mm),取二者的平均值。结果 常规皮肤试验0.8μgM、A、M+E及E+A诱发豚鼠DTH的平均直径与PPD相比无显著性差异 (P>0.05),而0.8μgE抗原及M+A诱发豚鼠DTH的平均直径与PPD相比有显著性差异(P<0.05)。时间效应 :重组抗原及其混合物诱发豚鼠DTH的平均直径24h平均直径显著高于48h平均直径 (P<0.05),24h测量效果较好。轮圈法皮肤试验排除个体差异后,结果与常规皮肤试验结果一致。结论 从试验结果看,重组ESAT6抗原及MTP64与Ag85A混合物诱发豚鼠DTH反应强于PPD。  相似文献   
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