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81.
82.
PROBLEM: Abortion of chromosomally normal embryos in the CBA X DBA/2 mating combination is triggered by release of Th1 cytokines (tumor necrosis factor [TNF]-alpha, interferon [IFN]-gamma, and interleukin [IL]-1), which cause abortion via a novel prothrombinase, Fgl2, and polymorphonuclear leukocytes. The site of activation may be maternal vascular endothelium on arteries and veins nourishing the placenta. Activation of coagulation is also prominent in spontaneous abortion of chromosomally normal human embryos. We asked where is Fgl2 up-regulated in the uterus in murine abortions, and if similar Fgl2 expression occurs in human pregnancy failure. METHODS: Control CBA X DBA/2 pregnant mice, or from mice injected with TNF-alpha + IFN-gamma on day 7.5 of gestation, were removed on day 8.5, fixed, sectioned, and subject to in situ hybridization for Fgl2. Sections were also stained for fibrin. Elective first trimester termination samples or biopsies taken early in the course of a recurrent miscarriage were similarly fixed, sectioned, and analyzed by in situ hybridization. Control and cytokine-treated mice were anticoagulated with heparin, an activator of antithrombin III, and/or the direct anti-thrombin inhibitor hirudin. RESULTS: Low level Fgl2 expression localized to basal decidua remote from the embryo was noted in control mice; cytokine treatment, which causes greater than 80% of abortions, produced a striking up-regulation in this area as well as in a band at the junction of decidua and myometrium. Trophoblast also became strikingly positive. Fgl2 expression was associated with increased fibrin staining. Anticoagulation significantly protected against abortions, but doses were limited by the complication of retroplacental hemorrhage. In tissue from normal first trimester pregnancy, minimal Fgl2 positivity was seen in some villous syncytiotrophoblast, in villous stroma, cytotrophoblast, and in some cells in decidua. In spontaneous abortion of normal embryo, striking Fgl2 positivity was seen in syncytiotrophoblast and extravillous cytotrophoblast, in association with areas of thrombus formation. CONCLUSIONS: Fgl2 appears to be physiologically expressed and may protect against the internal danger of maternal and/or fetal bleeding during pregnancy and at parturition; a role in inhibiting transplacental traffic is also possible. External dangers in the form of stress, endotoxin, and antigens eliciting Th1 cytokine responses upregulate Fgl2 prothrombinase in trophoblast as well as in decidua, which results in spontaneous abortion of immunogenetically "weaker" embryos.  相似文献   
83.
目的 研究准备抗病毒治疗的慢性丙型肝炎患者的免疫特点.方法 将30例慢性丙型肝炎患者和10例正常对照外周血单个核细胞(PBMC)体外培养72 h后,用ELISA法检测培养上清中细胞因子IL-2、IL-4、IL-10、IL-12、IFN-γ和TNF-α的浓度.结果 (1)慢性丙型肝炎患者PBMC培养上清中IFN-γ、IL-10和TNF-α的水平明显升高(P<0.05),没有检测到IL-2、IL-4、IL-12的基础分泌.(2)不同病情患者间的细胞因子的分泌水平差异无统计学意义(P>0.05).结论 慢性丙型肝炎患者体内TH2型细胞因子的分泌占优势.提示通过调整TH1/TH2失衡可能达到抗病毒治疗目的.  相似文献   
84.
目的: 抗体蛋白质芯片初步筛选常见细胞因子在卵巢癌耐药细胞株中的表达。 方法: 对6株卵巢癌细胞分别进行平行药敏试验及细胞因子抗体蛋白质芯片检测,同时筛选78种细胞因子的表达差异,并进行两两比较。 结果: 不同种类卵巢癌细胞系对于ADM的IC50值从高到低前3位依次为SKOV3,OVCAR5,OVCAR4;CBPDA为IGROV1,SKOV3,OVCAR3;TAXOL为OVCAR4,SKOV3,IGROV1;VP16为OVCAR4,OVCAR5,OVCAR8。在对一线化疗药ADM和 CBPDA耐药性较高的SKOV3细胞中GRO,IL-6,IL-8和TIMP-2均较其余5株相对敏感细胞增高,对二线化疗药TAXOL,VP16耐药性较高细胞株OVCAR4中IL-6,IL-8较之IGROV1,OVCAR3,OVCAR5升高。 结论: 在常见分泌型细胞因子中,GRO,IL-6,IL-8和TIMP-2升高与一线化疗药ADM和CBPDA耐药性相关,IL-6,IL-8与二线化疗药TAXOL,VP16耐药性相关,不同来源的卵巢癌细胞分泌型蛋白作用机制可能存在共同的上述几种蛋白参与的调节体系。  相似文献   
85.
张斗霞  张丽梅  张凌  白明 《微循环学杂志》2005,15(2):36-38,F003
目的:探讨兔急性肺血栓栓塞症(PTE)时血浆及支气管肺泡灌洗液(BALF)中TNF-α,IL-8、IL-10的水平和地塞米松(Dex)的影响。方法:采用自体血栓回输法建立兔急性PTF模型。36只兔随机分为对照组、Dex治疗组和PTE模型组。用ELISA方法检测上述细胞因子(CK)水平,术毕肺组织行病理观察。结果:栓塞后上述CK均有升高,治疗后TNF-α、IL-8均有下降,IL-10变化不明显。组织病理学可见栓塞后肺动脉内血栓形成,肺组织萎缩、出血、炎性反应明显,Dex治疗后肺组织病理改变明显减轻。结论:PTE后促炎性CK在引起肺部炎性反应和肺组织及肺动脉病损中起了重要作用,抗炎治疗可以明显减轻CK引起的这种损伤。抗炎治疗能降低PTE急性期病死率,改善远期预后,CK可能起了很重要的作用。  相似文献   
86.
SARS患者血清IL-8、IL-12和TGF-β1的检测及意义   总被引:5,自引:0,他引:5  
目的 :探讨SARS患者血清IL 8、IL 12和TGF β1在SARS冠状病毒感染致病中的作用。 方法 :应用酶联免疫吸附法 (ELISA)测定广州地区 2 8例SARS冠状病毒感染患者双份血清IL 8、IL 12和TGF β1的水平。实验数据采用两样本均数t检验法。结果 :2 8例SARS冠状病毒感染者血清IL 8水平、病程第 2周IL 12水平比正常健康对照组明显降低 (P <0 0 5 )。SARS冠状病毒感染者血清TGF β1水平与对照组比较无明显差异 (P >0 0 5 )。 结论 :IL 8和IL 12在SARS冠状病毒的致病与免疫过程中可能起降低细胞免疫功能作用  相似文献   
87.
Cytokine production in the spleens of mice infected with the protozoan parasite Trypanosoma cruzi was analyzed in three models which differ in the outcome of the infection. Using immunocytochemical techniques to detect cytokine-producing cells, the production of type 1 [interleukin-2 (IL-2) and interferon (IFN)-γ], type 2 (IL-4, IL-5, IL-10), inflammatory [tumor necrosis factor (TNF)-α, IL-1α, IL-6] and regulatory (transforming growth factor-β) cytokines were examined. With the exception of IL-4 and IL-5, cells producing all of the cytokines assayed were detected in both the resistant and susceptible models of T. cruzi infection. Cells producing IL-4 and IL-5 were not detected until later in infection in the resistant mice (>34 days), at about the time animals of the susceptible strain succumb to the infection. Mice of the susceptible model showed a slight delay in the appearance of cells producing the type 1 cytokines IL-2 and IFN-γ and an earlier appearance of TNF-producing cells, in comparison to resistant mice. Cells producing IL-2 or IL-10 were transient in their appearance in the spleen while cells producing IL-1, IL-4, IL-5, IL-6, IFN-γ, TNF, or TGF-β were first detectable in either the acute or post-acute stage of the infection and persisted up to 700 days post infection in two different resistant models of the infection. Cells producing IFN-γ, TNF-α and TGF-β were particularly numerous even very late in the infection. Double-staining techniques were used to show that the vast majority of the IFN-γ-producing cells in the spleen were CD4?, CD8? α/β TCR+ T cells. This study confirms the transience of IL-2 production in the acute stage of T. cruzi infection and the persistent and simultaneous production of type 1 and type 2 cytokines during the late-acute and chronic stages of the infection. Susceptibility or resistance to T. cruzi infection does not associate with a Th2 pattern of cytokine production in the three models examined in this study. The overlapping pattern of type 1 and type 2 cytokine-producing cells in both the acute and chronic stages of T. cruzi infection demonstrates that longterm infections do not necessarily lead to a dominance of either type 1 or type 2 cytokine production.  相似文献   
88.
The previously observed occurrence of antineutrophil cytoplasmic autoantibodies (ANCA) in patients who have cystic fibrosis (CF), together with the reported decrease in IgG2, a Th1-controlled isotype, suggests a potential for Th1/Th2 imbalance in CF patients with a possible Th2 predominance. 48 CF patients and 16 controls had levels of IFNgamma, IL-4, and IL-10 measured in supernatants of whole blood cell cultures stimulated by lipopolysaccharide (LPS) and phytohemaglutinine (PHA). The patients were divided into 2 groups: "low responders", having negligible secretion of cytokines (IFNgamma: 10.0-200.0 pg/ml, IL-4: 0.0-0.3 pg/ml) and "high responders", producing high levels of both IFNgamma (500.0-2000.0 pg/ml) and IL-4 (1.0-200.0 pg/ml). There was a statistically significant (P < 0.01) deterioration of lung function measured by an FEV(1) decline by 11.2% over 3 years in the "low responder" group. 10 of 16 "low responders" had chronic lung infections with P. aeruginosa while such infection was less prevalent in the "high responder" group where only 13 of 32 CF patients had positive cultures. A shift towards Th2 response was observed in the "high responder" group as children chronically infected with P. aeruginosa had greater IL-4 production than non-infected CF patients within the same cohort. ANCA autoantibodies were found only in the "high responder" group. Th2 immune response predominance in a subset of CF patients is associated with chronic P. aeruginosa infection.  相似文献   
89.
Immunity against Eimeria-infections is highly specific and it depends on cell-mediated effector mechanisms. Infections of BALB/c mice with 1000 sporulated oocysts of Eimeria falciformis led to protection against challenge infections. Treatment with the anticoccidium Toltrazuril, during primary infection, terminated the ongoing disease and did not interfere with the establishment of protective immunity against challenge infections. Mesenteric lymph node cells of infected, treated as well as non-treated and challenged BALB/c mice, showed a similar proliferation upon stimulation with parasite antigen. In contrast, neither cells of the Peyers patches, intraepithelial lymphocytes, nor spleen cells responded to stimulation with parasite antigens. Cells from all compartments and of all investigated groups proliferated and released the cytokines IFN- and IL-4 in response to the mitogen Concanavalin A. The number of cells releasing IFN- or IL-4 was not dependent on the status of infection or previous treatment with Toltrazuril. The serum IgG response against total sporozoite antigens of individual mice showed that in addition, a systemic humoral response developed in infected mice, independent of a previous drug treatment, although the specific IgG antibody concentration was higher in non-treated mice. Thus, Toltrazuril does not impair the parasite specific intestinal cellular and systemic antibody response and does not prevent the development of protection against challenge infection.  相似文献   
90.
Effector T cells fall into two subpopulations based on cytokine-secretion. Type 1 cells secrete IFN-gamma, whereas type 2 cells secrete IL-4, IL-10, and GM-CSF. NKT cells represent a third subpopulation that secretes similar cytokines and have been associated with immunoregulation. Using the TS/A adenocarcinoma, we assessed the phenotype and kinetics of tumor-infiltrating lymphocytes (TIL) in mice challenged subcutaneously in the mammary region. Flow cytometric analysis shows that T cells do not infiltrate the primary tumor site until days 7-14 following tumor challenge. Both CD4 and CD8 TILs were predominantly CD44(High) and expressed CD25, CD69, and CD95 cell surface activation markers. Activated CD4/CD44(High) TIL numbers reached peak levels at day 21 that precipitously decreased by day 28 whereas corresponding CD8 cell numbers progressively increased, however, at lower levels and with later kinetics. Intracellular cytokine staining showed that greater numbers of IL-4-producing Th2 cells were elicited and with earlier kinetics than that of IFN-gamma-producing Th1 cells. T cells co-expressing DX5 (CD3(+)/DX5(+)) emerged (>21 days), suggesting a recruitment of NK-like T cells at later stages of tumor progression. Moreover, tumors selectively up-regulated TGF-beta, MIF, and IP-10 gene expression at times as early as day 4, with peak levels at day 7 in vivo. Such gene expression remained elevated and correlated with a continued progression in tumor growth suggesting that preferential effector cell recruitment and production of select factors during different stages of tumor maturation may aid in regulating effective endogenous antitumor responses in progressive breast cancer.  相似文献   
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