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91.
The clinical role and potential molecular mechanisms of microRNA-449c-5p (miR-449c-5p) in hepatocellular carcinoma (HCC) tissues remains unclear. Combining multiple bioinformatic tools, we studied the miR-449c-5p expression levels in HCC tissues and explored possible target genes and related signaling pathways. First, miR-449c-5p expression data from microarrays provided by publicly available sources were mined and analyzed using various meta-analysis methods. Next, genes that were downregulated after miR-449c-5p mimic transfection into HCC cells were identified, and in silico methods were used to predict potential target genes. Several bioinformatic assessments were also performed to evaluate the possible signaling pathways of miR-449c-5p in HCC. Five microarrays were included in the current study, including GSE98269, GSE64632, GSE74618, GSE40744 and GSE57555. The standard mean difference was 0.44 (0.07–0.80), and the area under the curve was 0.68 (0.63–0.72), as assessed by meta-analyses, which consistently indicated the upregulation of miR-449c-5p in HCC tissues. A total of 2244 genes were downregulated after miR-449c-5p mimic transfection into an HCC cell line, while 5217 target genes were predicted by in silico methods. The overlap of these two gene pools led to a final group of 428 potential target genes of miR-449c-5p. These 428 potential target genes were primarily enriched in the homologous recombination pathway, which includes DNA Polymerase Delta 3 (POLD3). Data mining with Oncomine and the Human Protein Atlas showed a decreasing trend in POLD3 mRNA and protein levels in HCC tissue samples. This evidence suggests that miR-449c-5p could play an essential role in HCC through various pathways and that POLD3 could be a potential miR-449c-5p target. However, these in silico findings should be validated with further experiments.  相似文献   
92.
Polycystic ovary syndrome (PCOS) is one of the most complex and common reproductive and endocrinologic disorders in the child-bearing age of women. Recently, miR-222 were reported to be associated with the etiology of PCOS. However, the function of miR-222 during the pathogenesis of PCOS remains unclear. In the present study, we aimed to investigate the role of miR-222 in PCOS. Firstly, miR-222 expression was examined by quantitative real-time PCR (qRT-PCR) in PCOS. The effects of miR-222 on proliferation, apoptosis and cell cycle in KGN cells were analyzed by CCK-8 assay and flow cytometry analysis, respectively. In addition, bioinformatics analysis was used to predict the target genes of miR-222, and dual-luciferase reporter assay was applied to verified the interaction between miR-222 and p27 Kip1 in KGN cells. Moreover, the expressions of p27 Kip1 in KGN cells treated with miR-222 mimics or miR-222 inhibitor were evaluated by qRT-PCR and western blot assays. The results showed that the expression of miR-222 was remarkably upregulated in PCOS tissues compared with corresponding normal tissues. In the gain-of-function and loss-of-function assays, we revealed that miR-222 mimics significantly promoted cell proliferation, while miR-222 inhibitor induced cell apoptosis and cell cycle arrested. Furthermore, p27 Kip1 was identified as a target gene of miR-222, and could be negatively regulated by miR-222 mimics in KGN cells. In conclusion, our findings suggested that miR-222 may promote the progression of PCOS by targeting p27 Kip1.  相似文献   
93.
目的总结近年来股骨转子间骨折在稳定性重建方面的概念演化与研究进展。方法查阅国内外相关文献并结合自身经验,从股骨转子间骨折的解剖特点、稳定型骨折与不稳定型骨折分类、稳定性复位与不稳定性复位、术中加压初始稳定与术后滑动二次稳定、内固定术后稳定性评估、早期下地站立负重等方面进行总结分析。结果股骨转子间骨折发生于股骨颈干骺端转换区,具有天然的内翻不稳定倾向。骨折复位质量是影响后续内固定物安放的最重要前提因素。判断骨折复位质量有对线和对位两方面,对线采用 Garden 指数;在对位方面,随着皮质对位理念(正性、中性、负性)的提出,特别强调前内侧皮质的相互砥住支撑(解剖、正性),是获得骨折稳定性复位的关键,而不再强调后内侧小转子骨块的作用。术后影像学的稳定性评分为早期下地站立负重提供了量化指标。但术中的前内侧皮质支撑复位,在术后头颈骨块滑动获得二次稳定的过程中,仍有皮质对位丢失现象,需研究其危险因素和防范措施。结论股骨转子间骨折在取得良好对线的基础上,只要获得了前内侧皮质的相互砥住和支撑,并用内固定器械维持住,就获得了术后稳定性。术后稳定性评分优良者,可以安全地早期下地负重、站立行走活动。  相似文献   
94.
95.

Background

The clinical effectiveness of cardiac rehabilitation (CR) on health-related quality of life (HRQOL) is an area that has not been consistently explored. The objective of this systematic review was to evaluate the effectiveness of providing any core component of CR on HRQOL domains.

Methods

We performed a meta-analysis and meta-regression of randomized controlled trials (RCTs) on the core components of CR. RCTs included adult patients with diagnosed coronary artery disease via angiography, myocardial infarction, angina, or who had undergone coronary revascularization. The Cochrane Library, MEDLINE, EMBASE, CINAHL, SCI-EXPANDED, Psych INFO, and Web of Science were searched from inception to April 27, 2017. Outcomes included overall, physical, emotional, and social HRQOL. Outcomes were reported as standardized mean change (SMC) with 95% confidence intervals (CIs). Effect size changes of 0.2, 0.5, and 0.8 SD units reflect a small, moderate, and large effect, respectively.

Results

Forty-nine reports of 41 RCTs with 11,747 patients were included. Summary effect sizes were: overall HRQOL SMC, 0.28 (95% CI, 0.05-0.50), physical HRQOL SMC, 0.47 (95% CI, 0.13-0.81), emotional HRQOL SMC, 0.37 (95% CI, ?0.02 to 0.77), and social HRQOL SMC, 0.13 (95% CI, ?0.06 to 0.32). Meta-regression revealed type of CR intervention and year of publication as positive statistically significant treatment effect modifiers.

Conclusions

Receiving CR was shown to improve HRQOL, with exercise-, nonexercise-, and psychological-based interventions playing a vital role. Although these improvements in HRQOL were modest they still reflect an incremental benefit compared with receiving usual care.  相似文献   
96.
miRNAs是一类长度约为20~25个核苷酸,参与基因调控表达的内源性非编码RNA。miR-149作为miRNAs的重要成员,在多种肿瘤中表达异常,其表达水平与肿瘤细胞增殖、转移、凋亡、耐药、患者的早期诊断及预后密切相关。因此,miR-149有望成为新一类抗肿瘤治疗的靶点。  相似文献   
97.
Antiphospholipid antibody syndrome (APLS) is a rare disorder characterized by a hypercoagulable state. Manifestations include arterial or venous thrombosis, recurrent fetal wastage, coronary artery disease, valvular heart disease, dilated cardiomyopathy, pulmonary artery hypertension, and intracardiac thrombus. Most commonly mitral valve is affected followed by aortic and then tricuspid valve. In this report, a rare case of spontaneous aortic thrombosis with tricuspid stenosis uncomplicated by other valve lesions is presented with clinical and echocardiographic studies and computed tomographic images.  相似文献   
98.
99.
《中国现代医生》2020,58(2):34-37+41
目的研究中缝核miR-16以及5-羟色胺转运体(serotonin transporter,SERT)的表达在失眠症发病机制中的作用。方法 20只雌性SD大鼠,随机分成对照组和失眠组。失眠组大鼠接受腹腔注射对氯苯丙氨酸(pchlorophenalanine,PCPA)350 mg/(kg·d),连续3 d,对照组给予等量生理盐水。取中缝核组织,测定其miR-16、SERT m RNA与SERT蛋白水平,进行注射前后的组间比较。结果失眠组大鼠中缝核miR-16相对水平(1.23±0.33)与对照组(0.71±0.25)比较明显升高,差异具有统计学意义(t=6.68,P=0.000);而失眠组SERT mRNA相对水平(0.68±0.14)以及SERT蛋白相对水平(0.28±0.11)显著低于相应的对照组(1.06±0.30,0.57±0.15)(t=3.94,P=0.004;t=4.69,P=0.002)。结论中缝核miR-16以及SERT的异常表达,可能参与了失眠症的发病机制。  相似文献   
100.
目的:研究miR-194、EZH2对甲状腺癌细胞增殖、迁移和侵袭的影响,并探讨其作用机制。方法:采用qRT-PCR法检测甲状腺癌组织、癌旁正常组织及甲状腺癌细胞和正常甲状腺上皮细胞中miR-194和EZH2的mRNA表达;将miR-194(转染miR-194 mimics)、miR-NC(未转染细胞)、inhibitor-NC(转染空inhibitor)、miR-194 inhibitor(转染miR-194 inhibitor)、si-EZH2(转染si-EZH2)、miR-194+Vector(miR-194 mimics和pcDNA 3.1共转染)、miR-194+EZH2(miR-194 mimics和pcDNA 3.1-EZH2共转染)均以脂质体法转染到SW579、IHH-4细胞;Western blot检测细胞中EZH2的蛋白表达;MTT法检测细胞的增殖;Transwell检测细胞的迁移和侵袭;双荧光素酶报告基因检测实验检测细胞荧光素酶活性。结果:与正常组相比,甲状腺癌组EZH2的表达显著升高,miR-194的表达显著降低;与人正常甲状腺上皮细胞相比,甲状腺癌细胞中EZH2表达显著升高,miR-194的表达显著降低,且过表达miR-194和沉默EZH2均可抑制甲状腺癌细胞增殖、迁移和侵袭。EZH2为miR-194的靶标,且EZH2可逆转过表达miR-194对甲状腺癌细胞增殖、迁移和侵袭的抑制作用。结论:miR-194可抑制甲状腺癌细胞的增殖、迁移和侵袭,可能与靶向EZH2有关,将可为miR-194靶向治疗甲状腺癌提供依据。  相似文献   
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