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991.
OBJECTIVE: To investigate the association between angiotensinogen gene M235T polymorphism and ischemic stroke in East Asians. DATA RETRIEVAL: A computer-based online search was conducted in PubMed, Google scholar, China National Knowledge lnfrastructure database between January 1990 and April 2012 for relevant studies. The were angiotensinogen or AGT, polymorphism or genetic and ischemic stroke or cerebral infarction. SELECTION CRITERIA: Case-controlled studies addressing the correlation between angiotensinogen gene M235T polymorphism and ischemic stroke in East Asians were included. The distribution of genotypes in the included studies was tested for Hardy-Weinberg equilibrium. Quality evaluation of the included studies was conducted by two physicians. Statistical analyses were carried out using Stata 12.0 software for meta-analysis. Heterogeneity tests, sensitivity analysis and publication bias were also conducted. MAIN OUTCOME MEASURES: The association between angiotensinogen gene M235T polymorphism and ischemic stroke risk in East Asians was assessed. RESULTS: Six relevant studies involving 891 patients with ischemic stroke and 727 controls were included in this meta-analysis. Results showed that there was a significant association between angiotensinogen gene M235T polymorphism and the risk of ischemic stroke in East Asians (T vs. M: odds ratio (OR) = 1.54, 95% confidence interval (CI) = 1.10-2.16; TT vs. MM: OR = 2.24, 95%CI = 1.37-3.66; TT vs. MT: OR = 1.76, 95%CI = 1.41-2.20; MM + MT vs. TT: OR = 0.57, 95%CI = 0.46-0.70). Sensitivity analysis confirmed that the study results were stable and reliable, with no publication bias. CONCLUSION: The angiotensinogen gene M235T polymorphism is associated with ischemic stroke in East Asians, and the TT genotype and T allele are risk factors for ischemic stroke.  相似文献   
992.
目的通过前瞻性研究,对比分析国产髋关节假体与国际品牌髋关节产品的全髋关节置换术后近期疗效。方法以我科自2009年3月至2010年4月由同一组手术医生进行的国产髋关节假体全髋关节置换26例患者(26髋)为研究对象,并与同期本手术组医生所进行的国际品牌的26例髋对比分析。实验组和对照组术前及术后均行Harris评分,实验组术前平均(37.6±4.32)分,对照组术前平均(38.7±4.16)分。所有患者进行平均17个月随访。结果对实验组和对照组分别统计术后1周、4周、3个月、半年Harris评分。实验组术后Harris平均分较术前明显提高(<0.05),两组间术后对比无统计学意义(>0.05)。实验组病例术后出现1例置换关节脱位,两组均无明显下肢深静脉血栓症状、感染、下肢不等长及坐骨神经损伤等并发症发生。结论实验组在近期疗效上能达到与对照组同样的满意效果。全髋关节置换术能够明显解除患侧关节疼痛、改善关节功能;对于股骨颈骨折患者能早期恢复活动;避免长期卧床所致的并发症;使患者术后明显提高生活质量。  相似文献   
993.
A star-shaped biodegradable polymer, mannitol-core poly(d,l-lactide-co-glycolide)-d-α-tocopheryl polyethylene glycol 1000 succinate (M-PLGA-TPGS), was synthesized in order to provide a novel nanoformulation for breast cancer chemotherapy. This novel copolymer was prepared by a core-first approach via three stages of chemical reaction, and was characterized by nuclear magnetic resonance, gel permeation chromatography and thermogravimetric analysis. The docetaxel-loaded M-PLGA-TPGS nanoparticles (NPs), prepared by a modified nanoprecipitation method, were observed to be near-spherical shape with narrow size distribution. Confocal laser scanning microscopy showed that the uptake level of M-PLGA-TPGS NPs was higher than that of PLGA NPs and PLGA-TPGS NPs in MCF-7 cells. A significantly higher level of cytotoxicity was achieved with docetaxel-loaded M-PLGA-TPGS NPs than with commercial Taxotere®, docetaxel-loaded PLGA-TPGS and PLGA NPs. Examination of the drug loading and encapsulation efficiency proved that star-shaped M-PLGA-TPGS could carry higher levels of drug than linear polymer. The in vivo experiment showed docetaxel-loaded M-PLGA-TPGS NPs to have the highest anti-tumor efficacy. In conclusion, the star-like M-PLGA-TPGS copolymer shows potential as a promising drug-loaded biomaterial that can be applied in developing novel nanoformulations for breast cancer therapy.  相似文献   
994.
Newcastle disease virus (NDV) is a potential antitumor agent, and its antitumor effect has been evaluated in preclinical tests. However, the mechanisms of NDV‐based antitumor therapy are still not completely clear. In the present study we found that NDV‐stimulation enhanced the killing ability of mouse spleen natural killer (NK) cells towards mouse hepatoma cell lines, and tumor necrosis factor (TNF)‐related apoptosis‐inducing ligand (TRAIL) plays an important role in this tumoricidal activity. NDV stimulation induced up‐regulation of TRAIL both at the mRNA and protein levels in NK cells. Blocking TRAIL by antibody (Ab) almost completely eliminated the killing effect of NK cells on hepatoma cell lines. Furthermore, neutralizing interferon (IFN)‐γ by Ab could inhibit TRAIL expression and tumoricidal activity of NDV‐stimulated NK cells. These results indicated a substantial role of TRAIL as an effector molecule in NDV‐induced NK cells mediated tumoricidal activity. The NDV stimulation triggered TRAIL expression in mouse spleen NK cells could be mediated by IFN‐γ induction. Anat Rec, 296:1552–1560, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
995.
Biglycan (BGN), an extracellular matrix component, has been reported to play a crucial role in the tumor progression of various cancers. However, the relation between the expression of BGN and clinical prognosis has not been studied yet. We therefore carry out the present study to elucidate the role of BGN in predicting outcomes of patients with esophageal squamous cell carcinoma (ESCC). In this study, the expression of BGN in 170 cases of ESCC tissues and matched 46 adjacent non-tumorous tissues was measured by quantitative real-time PCR and immunohistochemistry. Upregulation of BGN occurred in approximately 60% of primary ESCCs compared with their non-tumor counterparts. In addition, high expression of BGN was significantly associated with clinical stage (P = 0.009), tumor invasion (P = 0.006) and lymph node metastasis (P = 0.046). The 5-year disease-specific survival (DSS) in high expression of BGN group is poorer than that in low level expression group (36.8% VS 57.4%, P = 0.006). Stratified analysis according to the pathological stage revealed its discernibility on DSS was only pronounced in patients with advanced clinical stage (P = 0.010). Cox multivariate analysis revealed that pathologic N category (P < 0.001; hazard ratio, 2.482, 95% CI, 1.576-3.909) and BGN expression (P = 0.019; hazard ratio, 1.713, 95% CI, 1.092-2.688) were two independent prognostic factors. The findings of the present study provide evidence that BGN represents a potential novel prognostic biomarker for resected ESCC patients in advanced clinical stage.  相似文献   
996.
Despite the recent realization of Interleukin (IL)-35 in tumorigenesis, its exact impact on colorectal cancer (CRC) progression and prognosis, however, is yet to be elucidated clearly. We thus in the present report conducted comparative analysis of IL-35 levels between CRC patients and matched control subjects. IL-35 is highly expressed in all CRC tissues, which can be detected in vast majority of colorectal cancer cells. IL-35 levels in CRC lysates and serum samples are highly correlated to the severity of malignancy and the clinical stage of tumor. Particularly, a significant reduction for serum IL-35 was noted in patients after surgical resection, indicating that IL-35 promotes CRC progression associated with poor prognosis. Mechanistic study demonstrated a significant correlation between serum IL-35 levels and the number of peripheral regulatory T (Treg) cells in CRC patients, suggesting that IL-35 implicates in CRC pathogenesis probably by inducing Treg cells, while cancer cell-derived IL-35 may also recruit Treg cells into the tumor microenvironment in favor of tumor growth. Together, our data support that IL-35 could be a valuable biomarker for assessing CRC progression and prognosis in clinical settings.  相似文献   
997.
Heme oxygenase-1 (HO-1) is a stress-inducible rate-limiting enzyme in heme degradation that confers cytoprotection against oxidative injury and performs a vital function in the maintenance of cell hemostasis. Increasing numbers of reports have indicated that mycoplasma-derived membrane lipoproteins/lipopeptides, such as macrophage-activating lipopeptide-2 (MALP-2), function as agents that stimulate the immune system by producing various inflammatory mediators, such as cytokines and cyclooxygenase 2 (COX-2), which play roles in the pathogenesis of inflammatory responses during mycoplasma infection. Here, we report that MALP-2 induced HO-1 mRNA and protein expression and upregulated HO-1 enzyme activity in THP-1 cells. Specific inhibitors of mitogen-activated protein kinases (MAPKs), SB203580, PD98059, and SP600125, significantly abolished HO-1 expression. In addition, MALP-2 also induced NF-E2-related factor 2 (Nrf2) translocation, and the silencing of Nrf2 expression in THP-1 cells decreased the levels of MALP-2-mediated HO-1 expression. Furthermore, COX-2 protein expression levels were upregulated in THP-1 cells in response to MALP-2, and transfection with small interfering RNAs of HO-1 significantly increased COX-2 accumulation. These results demonstrate that MALP-2 induces HO-1 expression via MAPKs and Nrf2 pathways and, furthermore, that MALP-2-induced COX-2 expression was modulated by HO-1 in THP-1 cells.  相似文献   
998.
Syphilis is a chronic infection caused by Treponema pallidum subsp. pallidum, and diagnosis with sensitive and specific methods is a challenging process that is important for its prevention and treatment. In the present study, we established a recombinant protein TpF1-based indirect immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) and a Western blot assay for human and rabbit sera. The 20-kDa recombinant protein TpF1 was detected by Western blotting performed with sera from rabbits immunized with recombinant TpF1 and infected with the T. pallidum Nichols strain and T. pallidum clinical isolates but was not detected by Western blotting with sera from uninfected rabbits. The sensitivity of the recombinant protein was determined by screening sera from individuals with primary, secondary, latent, and congenital syphilis (n = 82). The specificity of the recombinant protein was determined by screening sera from uninfected controls (n = 30) and individuals with potentially cross-reactive infections, including Lyme disease (n = 30) and leptospirosis (n = 5). The sensitivities of TpF1-based ELISAs were 93.3%, 100%, 100%, and 100% for primary, secondary, latent, and congenital syphilis, respectively, and the specificities were all 100% for sera from uninfected controls and individuals with potentially cross-reactive infections. In Western blot assays, the sensitivities and specificities of TpF1 for human sera were all 100%. The reactivities of TpF1 with syphilitic sera were proportional to the titers of the T. pallidum particle agglutination (TPPA) assay. These data indicate that the recombinant protein TpF1 is a highly immunogenic protein in human and rabbit infections and a promising marker for the screening of syphilis.  相似文献   
999.
Severe fever with thrombocytopenia syndrome virus (SFTSV), a newly discovered member of the Bunyaviridae family, is the causative agent of an emerging hemorrhagic fever, SFTS, in China. Currently, there are no vaccines or effective therapies against SFTS. In this study, a combinatorial human antibody library was constructed from the peripheral lymphocytes of 5 patients who had recovered from SFTS. The library was screened against purified virions for the production of single-chain variable-region fragments (ScFv). Of the 6 positive clones, one clone (monoclonal antibody [MAb] 4-5) showed neutralizing activity against SFTSV infection in Vero cells. MAb 4-5 was found to effectively neutralize all of the clinical isolates of SFTSV tested, which were isolated from patients in China from 2010 to 2012. MAb 4-5 was found to bind a linear epitope in the ectodomain of glycoprotein Gn. Its neutralizing activity is attributed to blockage of the interactions between the Gn protein and the cellular receptor, indicating that inhibition of virus-cell attachment is its main mechanism. These data suggest that MAb 4-5 can be used as a promising candidate molecule for immunotherapy against SFTSV infection.  相似文献   
1000.
目的:建立人皮肤成纤维细胞的体外原代及传代培养并鉴定的技术方法.方法:取临床无菌切除的幼儿包皮,利用胶原酶分离表皮和真皮,将真皮剪成肉糜状,再用胰蛋白酶消化,接种于培养皿,加少许含10%小牛血清的DMEM-高糖培养液进行培养,次日补加培养液.原代长满后,进行传代,并对所培养的细胞进行形态学观察及组化鉴定.结果:接种次日倒置镜下可见有长梭形细胞迁出、生长,5-6d进行传代,传代后约5d长满,可长期传代.免疫组化Vimentin表达阳性.结论:该方法可快速高效获得构建组织皮肤真皮所需的成纤维细胞.  相似文献   
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