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71.
Follicular lymphoma (FL) is a germinal center-derived B-cell lymphoma that is known to proliferate in the intrafollicular region. However, lymphoma cells can be identified in the extrafollicular regions, which are related to disease dissemination. We purified the intrafollicular and extrafollicular regions of FL cells by laser microdissection and conducted microarray analysis in order to characterize the gene expression profiles of FL cells from both regions. BCL2 and genes of germinal B-cell markers clearly separated intrafollicular and extrafollicular regions of reactive follicular hyperplasia, suggesting the adequacy of the current analysis. In FL cases, cytokine-related genes were significantly enriched in extrafollicular regions compared with those in the intrafollicular regions. In intrafollicular regions of FL, cell-cycle–related genes were enriched. We found that the FL cells in the extrafollicular region more strongly expressed IL3RA and CXCL12 than those of intrafollicular regions. The cytokines might be also derived from stroma cells in the extrafollicular regions, which may initiate activation and migration of the tumor cells to this region. Our results suggest that FL cell interaction with surrounding stroma cells plays an important role in the pathophysiology of FL and that such interactions should be a good target for therapy.  相似文献   
72.
目的:探讨引经药防风对痛泻要方调控腹泻型肠易激综合征(IBS-D)大鼠水液代谢和5-羟色胺(5-HT)信号系统的影响。方法:将40只IBS-D SD大鼠随机分为模型组,痛泻要方缺防风组(26 g·kg^-1),痛泻要方全方组(30 g·kg^-1)和痛泻要方倍用防风组(34 g·kg^-1),另取10只正常SD大鼠作为正常组,除正常组外,其余各组采用母子分离联合乙酸灌肠法,建立腹泻型肠易激综合征大鼠模型,造模后各组灌胃给予相应药物,连续14 d,观察并计算腹泻指数和粪便含水量,微量法检测肠黏膜Na^+-K^+-ATP酶活性,酶联免疫吸附测定(ELISA)检测5-HT的含量,化学发光法检测单胺氧化酶-A(MAO-A)活性,通过免疫组化法检测结肠中水通道蛋白4(AQP4)的表达,蛋白免疫印迹法(Western blot)检测下丘脑和结肠中5-HT受体3(5-HT3R),5-HT受体4(5-HT4R)和5-HT转运体(SERT)的蛋白表达水平。结果:与正常组比较,模型组大鼠的粪便含水量,5-HT含量,MAO-A酶活性,5-HT3R表达均显著升高(P<0.01),肠黏膜Na^+-K^+-ATP酶活性,AQP4,5-HT4R和SERT表达均显著降低(P<0.01);与模型组比较,各给药组大鼠的腹泻指数和粪便含水量、下丘脑与结肠中的5-HT含量,MAO-A酶活性,5-HT3R蛋白表达均明显降低(P<0.05,P<0.01),但痛泻要方缺防风组5-HT3R蛋白表达未见明显差异,各给药组肠黏膜Na^+-K^+-ATP酶活性,AQP4,5-HT4R和SERT表达均明显增加(P<0.05,P<0.01);与痛泻要方缺防风组比较,痛泻要方全方组和痛泻要方倍用防风组大鼠腹泻指数和粪便含水量,5-HT含量及MAO-A酶活性,5-HT3R的蛋白表达均明显降低(P<0.05,P<0.01),Na^+-K^+-ATP酶活性和SERT的蛋白表达明显增加(P<0.05,P<0.01)。结论:防风可增强痛泻要方改善IBS-D水液代谢、调控5-HT信号系统多靶点的效应,进一步证实了防风的引经增效作用。  相似文献   
73.
Cardiovascular complications are a side effect of cancer therapy, potentially through reduced blood vessel function. ONC201 (TIC10) is currently used in phase 2 clinical trials to treat high-grade gliomas. TIC10 is a phosphatidylinositol 3-kinase (PI3K)/AKT/extracellular signal-regulated kinase (ERK) inhibitor that induces apoptosis via upregulation of TNF-related apoptosis-inducing ligand, which via stimulation of FOXO and death receptor could increase eNOS upregulation. This has the potential to improve vascular function through increased NO bioavailability. Our aim was to investigate the role of TIC10 on vascular function to determine if it would affect the risk of CVD. Excised abdominal aorta from White New Zealand male rabbits were cut into rings. Vessels were incubated with TIC10 and AS1842856 (FOXO1 inhibitor) followed by cumulative doses of acetylcholine (Ach) to assess vessel function. Vessels were then processed for immunohistochemistry. Incubation of blood vessels with TIC10 resulted in enhanced vasodilatory capacity. Combination treatment with the FOXO1 inhibitor and TIC10 resulted in reduced vascular function compared to control. Immunohistochemical analysis indicated a 3-fold increase in death receptor 5 (DR5) expression in the TIC10-treated blood vessels but the addition of the FOXO1 inhibitor downregulated DR5 expression. The expression of DR4 receptor was not significantly increased in the presence of TIC10; however, addition of the FOXO1 inhibitor downregulated expression. TIC10 has the capacity to improve the function of healthy vessels when stimulated with the vasodilator Ach. This highlights its therapeutic potential not only in cancer treatment without cardiovascular side effects, but also as a possible drug to treat established CVD.  相似文献   
74.
基于代谢组学方法,对给予醋甘遂不同成分群(B,C)前后大鼠的粪便代谢物进行比较研究,探求与醋甘遂毒性相关的差异性代谢物和代谢通路,揭示醋甘遂的毒性作用机制。采用快速液相色谱串联四极杆飞行时间质谱(UFLC-Q-TOF-MS)技术,对大鼠粪便样本进行测定,结合主成分分析(PCA)和偏最小二乘-判别分析(OPLS-DA)等多种方法筛选并鉴定与醋甘遂毒性相关的生物标志物,并采用t检验进行单变量统计分析,考察给予醋甘遂成分群B,C后正常大鼠粪便这些生物标志物的含量变化,揭示醋甘遂成分群B,C对大鼠粪便代谢组的影响程度,并结合基于MetaboAnalyst数据库的代谢通路分析探求醋甘遂成分群B,C的毒性作用机制。结果显示,与空白组相比,醋甘遂成分群B和C组大鼠粪便样本代谢组发生了明显改变,且醋B组改变程度更大,发现并鉴定了16种醋甘遂毒性潜在生物标志物及5条相关代谢通路。醋甘遂的毒性作用可能与色氨酸代谢、初级胆汁酸生物合成、氨基糖和核苷酸糖代谢、嘌呤代谢和缬氨酸,亮氨酸和异亮氨酸降解等代谢通路的紊乱有关。该研究为醋甘遂的临床安全应用提供了科学依据。  相似文献   
75.
BackgroundOur previous study states that propofol suppresses proliferation and migration of papillary thyroid cancer (PTC) cells by downregulation of lncRNA ANRIL. This study intended to probe the downstream mechanism of ANRIL in PTC with potential microRNAs (miR) and genes.MethodsANRIL expression was detected in normal thyroid epithelial cells (Nthy-ori 3-1) and PTC cells (TPC-1, FTC-133, K1 and BCPAP). ANRIL expression was inhibited in TPC-1 and BCPAP cells to explore the effects of si-ANRIL in PTC malignant behaviors. The gain-and loss-of functions of ANRIL/miR-320a were performed to measure their roles in PTC. Levels of ANRIL, miR-320a, HMGB1, apoptosis- and Wnt/β-catenin and NF-κB pathways-related proteins were measured. Dual-luciferase reporter gene assay and RNA pull-down assay were applied to verify ANRIL/miR-320a/HMGB1 relation. si-ANRIL was transplanted into xenograft tumors in nude mice.ResultsANRIL was upregulated in TPC-1 and BCPAP cells. miR-320a targeted HMGB1, and ANRIL bound to miR-320a. In TPC-1 and BCPAP cells, si-ANRIL prevented PTC cell malignant behaviors, and inactivated the Wnt/β-catenin and NF-κB pathways; while si-ANRIL + miR-320a inhibition showed opposite trends. Overexpressing miR-320a promoted malignant behaviors of TPC-1 cells. In 6 μg/mL propofol-treated TPC-1 cells, miR-320a inhibition weakened propofol’s inhibitory effects on PTC cell growth. After ANRIL inhibition, the volume and weight of xenograft tumors were decreased.ConclusionPropofol upregulated miR-320a and reduced HMGB1 by downregulating ANRIL and inactivating the Wnt/β-catenin and NF-κB pathways, thus preventing PTC cell malignant behaviors. This study may offer new insights in PTC prevention and treatment.  相似文献   
76.
目的基于网络药理学和生物信息学方法探究左金丸抗幽门螺杆菌(Hp)感染的分子网络调控机制。方法通过中药系统药理学数据库和分析平台(TCMSP)检索左金丸化学成分,筛选并预测其入血活性成分和作用靶点,检索疾病数据库中与Hp感染相关的作用靶点,构建左金丸成分靶点与疾病靶点的交互网络,获得左金丸抗Hp的特征性基因;通过DAVID6.8数据库对上述特征性基因进行GO功能富集和KEGG通路富集分析;利用Cytohubba筛选出左金丸抗Hp感染的关键靶点。结果通过TCMSP筛选、预测得到左金丸32个入血活性成分和197个作用靶点。GO分析共得到199条富集结果,其中生物过程包含炎症反应、RNA信号转录、信号传导等152条,细胞组分包含细胞核、细胞外基质、蛋白复合物等19条,分子功能包含细胞因子活性、DNA结合、ATP结合等28条。KEGG分析结果显示,Jak-STAT信号通路、T细胞受体信号通路、细胞周期信号通路、Wnt信号通路等65条通路与左金丸抗Hp感染密切相关。经Cytohubba筛选得到CXCL8、IL10、IL4、VEGFA、MMP9等10个关键基因。结论左金丸抗Hp感染具有多成分、多靶点、多通路协同作用的特点,可为其活性成分研究和抗Hp药效及机制研究提供依据。  相似文献   
77.
多囊蛋白(polycystin,PC)作为一个细胞表面的膜受体,是一种位于细胞表面的多功能跨膜蛋白,在多种上皮细胞中表达。作为一种新型的机械敏感分子,参与常染色体显性多囊肾病、多囊肝等疾病中囊肿形成扩张、骨骼生长发育及创伤愈合等多种生理病理过程。近年来研究发现多囊蛋白与肿瘤的发生发展密切相关,通过cAMP/PKA、Wnt/β-catenin、mTOR、GSK3β等多个信号传导通路,参与肿瘤细胞的增殖、黏附、凋亡及迁移过程,并与肿瘤治疗及预后相关。现总结近年来PC在肿瘤中的生物学作用及研究进展作一综述。  相似文献   
78.
The endosome is a membrane-bound organ inside most eukaryotic cells, playing an important role in adaptive immunity by delivering endocytosed antigens to both MHC class I and II pathways. Here, by analyzing genotyping data from two published genome-wide association studies (GWASs), we evaluated associations between genetic variants in the endosome-related gene-set and survival of patients with nonsmall cell lung cancer (NSCLC). The discovery included 44,112 (3,478 genotyped and 40,634 imputed) single-nucleotide polymorphisms (SNPs) in 220 genes in a singlelocus analysis for their associations with survival of 1,185 NSCLC patients from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. After validation of the 821 survival-associated significant SNPs in additional 984 NSCLC patients from the Harvard Lung Cancer Susceptibility Study, 14 SNPs remained significant. The final multivariate stepwise Cox proportional hazards regression modeling of the PLCO dataset identified three potentially functional and independent SNPs (i.e., KIF16B rs1555195 C>T, NEDD4L rs11660748 A>G and rs73440898 A>G) with an adjusted hazards ratio (HR) of 0.86 (95% confidence interval [CI] = 0.79–0.94, p = 0.0007), 1.31 (1.16–1.47, p = 6.0 × 10−5) and 1.27 (1.12–1.44, p = 0.0001) for overall survival (OS), respectively. Combined analysis of the adverse genotypes of these three SNPs revealed a trend in the genotype-survival association (ptrend < 0.0001 for OS and ptrend < 0.0001 for disease-specific survival). Furthermore, the survival-associated KIF16B rs1555195T allele was significantly associated with decreased mRNA expression levels of KIF16B in both lung tissues and blood cells. Therefore, genetic variants of the endosome-related genes may be biomarker for NSCLC survival, possibly through modulating the expression of corresponding genes.  相似文献   
79.
目的:探索清肺化痰汤对慢性阻塞性肺疾病(COPD)的治疗作用及其机制研究。方法:应用烟雾吸入联合脂多糖(LPS)灌肺复合素的方法,建立COPD大鼠模型,造模成功后将大鼠随机分为6组,分别为正常组,COPD模型组,清肺化痰汤低、中、高剂量组和氨溴索组。造模28 d后开始给药,清肺化痰汤低、中、高剂量7.5,15,30 g·kg~(-1),氨溴索35 mg·kg~(-1),连续给药14 d。免疫组化和实时荧光定量聚合酶链式反应(Real-time PCR)检测肺组织囊性纤维化跨膜转导调节因子(CFTR)蛋白和mRNA的表达。应用LPS诱导NCI-H292细胞建立黏液高分泌模型,实验分为8组,分别为空白组,LPS组,LPS+10%胎牛血清,LPS+生理血清,LPS+5%含药血清,LPS+10%含药血清,LPS+20%含药血清,LPS+AG490组。免疫荧光、蛋白免疫印迹法(Western blot)和Real-time PCR观察LPS刺激后的NCI-H292细胞中CFTR蛋白和mRNA的表达,Western blot检测LPS刺激后的NCI-H292细胞中Janus激酶2/信号转导与转录激活因子3(JAK2/STAT3)信号通路表达。结果:正常组大鼠肺组织管腔周围有大量棕褐色颗粒,COPD表达升高,与正常组比较,模型组大鼠肺组织管腔周围的棕褐色颗粒极少,COPD表达较低。与正常组比较,COPD模型组大鼠肺组织中CFTR mRNA和蛋白表达明显降低(P0.05);与模型组比较,清肺化痰汤低、中、高剂量组明显升高大鼠肺组织CFTR mRNA和蛋白表达水平(P0.05)。与空白组比较,LPS组NCI-H292细胞CFTR mRNA和蛋白表达显著降低(P0.01),p-JAK2,p-STAT3蛋白表达明显升高(P0.05);与模型组比较,清肺化痰汤5%,10%,20%含药血清组明显升高CFTR mRNA和蛋白表达,明显降低p-JAK2,p-STAT3蛋白表达(P0.05,P0.01)。结论:清肺化痰汤通过抑制JAK2/STAT3通路来上调CFTR治疗COPD。  相似文献   
80.
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