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991.
目的探讨芪三酚(Res)对人乳腺癌MDA—MB-231细胞增殖抑制的相关效应及其与MDCl基因的关系。方法以人乳腺癌MDA—MB-231细胞株为研究对象,采用MTS方法测定细胞增殖,应用吖啶橙荧光染色观察Res对乳腺癌MDA—MB-231细胞的影响,用RT-PCR与免疫印迹方法测定MDCl基因与蛋白表达水平,用小RNA干扰MDCl基因后,用流式细胞仪检测细胞的凋亡并观察其对Res的敏感性影响。结果40μmol/L以上的Res可显著抑制乳腺癌MDA—MB-231细胞的增殖(P〈0.05),给予0、60、120μmol/LRes能明显降低MDCl基因和蛋白的表达(P〈0.05)。用小RNA干扰MDC1基因后,流式细胞术分析显示,实验组(MDCl.siRNA)的细胞凋亡率[(45.13±6.2)%]较阴性对照组[(24.34±2.6)%]和未处理组[(17.69±4.9)%]明显上升(P〈0.05),MTS结果显示MDCl基因干扰后细胞对Res的敏感性增加。结论40μmol/L以上的Res可以抑制MDA-MB-231细胞的增殖,Res可以有效降低MDC基因和蛋白的表达并促进细胞的凋亡。用小RNA干扰MDCl基因(MDCl-siRNA)后,MDA-MB-231细胞对Res的敏感性增加。  相似文献   
992.
993.
Alzheimer's disease (AD) neuropathology is characterized by innate immune activation primarily through prostaglandin E2 (PGE2) signaling. Dedicator of cytokinesis 2 (DOCK2) is a guanyl nucleotide exchange factor expressed exclusively in microglia in the brain and is regulated by PGE2 receptor EP2. DOCK2 modulates microglia cytokine secretion, phagocytosis, and paracrine neurotoxicity. EP2 ablation in experimental AD results in reduced oxidative damage and amyloid beta (Aβ) burden. This discovery led us to hypothesize that genetic ablation of DOCK2 would replicate the anti-Aβ effects of loss of EP2 in experimental AD. To test this hypothesis, we crossed mice that lacked DOCK2 (DOCK2 −/−), were hemizygous for DOCK2 (DOCK2 +/−), or that expressed two DOCK2 genes (DOCK2 +/+) with APPswe-PS1Δe9 mice (a model of AD). While we found no DOCK2-dependent differences in cortex or in hippocampal microglia density or morphology in APPswe-PS1Δe9 mice, cerebral cortical and hippocampal Aβ plaque area and size were significantly reduced in 10-month-old APPswe-PS1Δe9/DOCK2 −/− mice compared with APPswe-PS1Δe9/DOCK2 +/+ controls. DOCK2 hemizygous APPswe-PS1Δe9 mice had intermediate Aβ plaque levels. Interestingly, soluble Aβ42 was not significantly different among the three genotypes, suggesting the effects were mediated specifically in fibrillar Aβ. In combination with earlier cell culture results, our in vivo results presented here suggest DOCK2 contributes to Aβ plaque burden via regulation of microglial innate immune function and may represent a novel therapeutic target for AD.  相似文献   
994.
Myeloid‐derived suppressor cells (MDSCs) accumulate in tumor‐bearing hosts and play a major role in tumor‐induced immunosuppression, which hampers effective immuno‐therapeutic approaches. β‐Glucans have been reported to function as potent immuno‐modulators to stimulate innate and adaptive immune responses, which contributes to their antitumor property. Here, we investigated the effect of particulate β‐glucans on MDSCs and found that β‐glucan treatment could promote the differentiation of M‐MDSCs (monocytic MDSCs) into a more mature CD11c+ F4/80+ Ly6Clow population via dectin‐1 pathway in vitro, which is NF‐κB dependent, and the suppressive function of M‐MDSCs was significantly decreased. Treatment of orally administered yeast‐derived particulate β‐glucan drastically downregulated MDSCs but increased the infiltrated DCs and macrophages in tumor‐bearing mice, thus eliciting CTL and Th1 responses, inhibiting the suppressive activity of regulatory T cells, thereby leading to the delayed tumor progression. We show here for the first time that β‐glucans induce the differentiation of MDSCs and inhibit the regulatory function of MDSCs, therefore revealing a novel mechanism for β‐glucans in immunotherapy and suggesting their potential clinical benefit.  相似文献   
995.
996.
Whole cell tumor vaccine (WCTV), as a potential treatment modality, elicits limited immune responses because of the poor immunogenicity. To address this issue, researchers have attempted to transduce a cytokine adjuvant into tumor cells, but these single-adjuvant WCTVs curtail the high expectations. In present study, we constructed a multi-adjuvant WCTV based on the nanoparticles modified with cell penetrating peptide, which could facilitate the transportation of granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin 2 (IL-2) into tumor cells. After inactivation, as-designed multi-adjuvant WCTV exhibited programmed promotions on DC recruitment, antigen presentation, and T-cell activation. In vivo evaluations demonstrated the satisfactory effects on tumor growth suppression, metastasis inhibition, and recurrence prevention. Therefore, the nanoparticles-based multi-adjuvant WCTV may serve as a high-performance treatment for anti-tumor immunotherapy.  相似文献   
997.
Schwann cell (SC), which plays a key role in peripheral nerve regeneration, is one of the most classic supportive cells in neural tissue engineering. However, the biological activity of SCs seeded in nerve scaffolds decays subsequently due to local hypoxia induced by ischemia. Thus, we aimed to investigate whether a synthetic oxygen carrier-enriched fibrin gel would provide a sustained oxygen release to cultured SCs in vitro for overcoming a temporary (48 h) oxygen deprivation. In this study, perfluorotributylamine (PFTBA)-based oxygen carrying fibrin gel was prepared to provide oxygen for SCs under normoxic or hypoxic conditions. The dissolved oxygen within the culture media was measured by a blood-gas analyzer to quantify the time course of oxygen release from the PFTBA-enriched fibrin gel. SCs were cultured in the presence or absence of PFTBA-enriched fibrin gel under normoxic or hypoxic conditions. The tolerance of SCs to hypoxia was examined by a cell apoptosis assay. The growth of cells was characterized using S-100 staining and a CCK-8 assay. The migration of cells was examined using a Transwell chamber. The mRNA of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial cell derived neurotrophic factor (GDNF), neural cell adhesion molecule (N-CAM) and vascular endothelial growth factor (VEGF) in SCs were assayed by RT-PCR. In addition, SCs cultured in 3D PFTBA-enriched hydrogel were characterized by Live/Dead staining and the mRNA levels of BDNF, NGF, GDNF, N-CAM and VEGF were assayed by RT-PCR. The results showed that the PFTBA-enriched fibrin hydrogel was able to promote cell adhesion, migration, and proliferation under hypoxic conditions. Interestingly, PFTBA applied through the fibrin hydrogel dramatically enhanced the mRNA of BDNF, NGF, GDNF, N-CAM and VEGF under hypoxic condition. These findings highlight the possibility of enhancing nerve regeneration in cellular nerve grafts through PFTBA increased neurotropic secretion in SCs.  相似文献   
998.
BackgroundAnxiety is common in stroke survivors and may adversely affect recovery. Polymorphisms of tryptophan hydroxylase2 (THP2) gene have been shown to be associated with anxiety disorders and other affective disorders. This study was aimed to investigate the association of two polymorphisms of THP2 gene, rs4570625 and rs4565946, with poststroke anxiety disorders in a Han Chinese population.MethodsThis case control study included 112poststroke anxiety patients and 246 non-anxious controls. All participants completed Hamilton Anxiety Rating Scale and DNA was extracted from blood and genotyped for the two polymorphisms of THP2 gene.ResultsResults revealed that the G allele of rs4570625 was associated with the increased risk of poststroke anxiety. In the female subgroup, both the GG genotype and G allele were observed to be significantly higher in case than in control. No significant difference in genotype and allele frequencies of the rs4565946 was found between case and control. Haplotype analysis identified that patients with the G-C haplotype had significantly increased the risk of poststroke anxiety.LimitationsMore than 20 TPH2 polymorphisms have been detected, some of which are tightly-linked and may function together, only two SNPs of TPH2 were investigated in this study.ConclusionsThe findings suggest that these polymorphisms in TPH2 gene are involved in development of poststroke anxiety in the Han Chinese population.  相似文献   
999.
Abstract

Objective: Recent studies have found that selenium (Se) levels were associated with the risk of Parkinson’s disease (PD), but the results were contradictory. Therefore, this meta-analysis was conducted to investigate the correlation between Se levels and PD.

Methods: PubMed, Embase and Web of Science were searched published up to 28 October 2019. The differences between groups were analyzed by forest plots and results were pooled and assessed using a random-effect model. Standardized mean difference (SMD) and 95% confidence interval (CI) were used to assess the association between Se levels and the risk of PD. Subgroup analysis, meta-regression, and sensitivity analysis were also conducted. Publication bias was estimated using Begg’s regression asymmetry test.

Results: Finally, 12 articles involving 601 PD patients and 749 controls were included in this meta-analysis. The meta-analysis revealed a significantly higher cerebrospinal fluid (CSF) Se level in PD patients than those in controls (SMD = 1.22; 95%CI [0.05, 2.39]; p?=?0.000). No publication bias was found.

Conclusion: The meta-analysis indicated that CSF Se levels in PD patients were significantly higher than those in controls.  相似文献   
1000.
Journal of Autism and Developmental Disorders - This study describes charges, outcomes, and recidivism in both the juvenile and adult criminal justice systems (CJS) for young adults aged 17 to...  相似文献   
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