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1.
Although the lung has extensive regenerative capacity, some diseases affecting the distal lung result in irreversible loss of pulmonary alveoli. Hitherto, treatments are supportive and do not specifically target tissue repair. Regenerative medicine offers prospects to promote lung repair and regeneration. The neonatal lung may be particularly receptive, because of its growth potential, compared to the adult lung. Based on our current understanding of neonatal lung injury, the ideal therapeutic approach includes mitigation of inflammation and fibrosis, and induction of regenerative signals. Cell-based therapies have shown potential to prevent and reverse impaired lung development. Their mechanisms of action suggest effects on both, mitigating the pathophysiological processes and promoting lung growth. Here, we review our current understanding of normal and impaired alveolarization, provide some rationale for the use of cell-based therapies and summarize current evidence for the therapeutic potential of cell-based therapies for pulmonary regeneration in preterm infants.  相似文献   
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The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) maintains a database of extremely preterm infants known as the Generic Database (GDB). Begun in 1987, this database now includes more than 91,000 infants, most of whom are extremely preterm (<29 weeks gestation). The GDB has been the backbone of the NRN, providing high quality, prospectively collected data to study the changing epidemiology of extreme prematurity and its outcomes over time. In addition, GDB data have been used to generate hypotheses for prospective studies and to develop new clinical trials by providing information about the numbers and characteristics of available subjects and the expected event rates for conditions and complications to be studied. Since its inception, the GDB has been the basis of more than 200 publications in peer-reviewed journals, many of which have had a significant impact on the field of neonatology.  相似文献   
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目的通过研究诱骗受体2(DcR2)在小鼠胚肾发育过程中的定位和表达,探讨DcR2在胚肾发育中与细胞衰老的关系。 方法分别选取胚龄为12.5 d、16.5 d、20.5 d和出生后8w小鼠的肾脏组织,使用过碘酸雪夫(PAS)染色观察肾组织形态,定量RT-PCR检测肾组织DcR2 mRNA表达水平,免疫组织化学染色观察DcR2的表达分布,免疫荧光共染检测DcR2与近端肾小管标志绒毛蛋白villin、远端肾小管标志水通道蛋白2(AQP-2)、衰老标志P16、胞核形态标志物核纤层蛋白B1(LaminB1)、增殖标志Ki-67和增殖细胞核抗原(PCNA)的共表达关系。 结果随着胚肾的发育,胚肾组织中DcR2 mRNA及蛋白表达逐渐增多,且明显高于成年肾脏;DcR2特异性表达于肾小管,且与villin共表达,但不与AQP-2共表达;DcR2阳性细胞高表达P16,却低表达LaminB1、Ki-67和PCNA。 结论DcR2特异性表达于胚肾近端肾小管细胞,且表达水平随胚龄增长而增多。此外,DcR2阳性细胞具有衰老相关表型,提示DcR2可能在胚肾发育过程中通过调控细胞衰老而具有重要作用。  相似文献   
4.
《Vaccine》2022,40(24):3380-3388
BackgroundWe evaluated the safety and immunogenicity of NVX-CoV2373, a recombinant SARS-CoV-2 nanoparticle vaccine, in healthy Japanese participants.MethodsThis phase 1/2, randomized, observer-blind, placebo-controlled trial conducted in Japan (two sites), enrolled healthy Japanese adults aged ≥ 20 years with no history/risk of SARS-CoV-2 infection and no prior exposure to other approved/investigational SARS-CoV-2 vaccines or treatments. Participants were stratified by age (< 65 or ≥ 65 years) and randomized to receive two doses of either NVX-CoV2373 (5 μg SARS-CoV-2 rS; 50 μg Matrix-M1) or placebo, 21 days apart. Primary outcomes were safety and immunogenicity assessed by serum IgG antibody levels against SARS-CoV-2 rS protein on day 36. Herein, we report the primary data analysis at 4 weeks after the second dose, ahead of 12-month follow-up completion (data cut-off: 8 May 2021).ResultsBetween 12 February 2021 and 17 March 2021, 326 subjects were screened, and 200 participants enrolled and randomized: NVX-CoV2373, n = 150; placebo, n = 50. Solicited adverse events (AEs) through 7 days after each injection occurred in 121/150 (80.7%) and 11/50 (22.0%) participants in the NVX-CoV2373 and placebo arms, respectively. In the NVX-CoV2373 arm, tenderness and injection site pain were the most frequently reported solicited AEs after each vaccination, irrespective of age. Robust immune responses occurred with NVX-CoV2373 (n = 150) by day 36: IgG geometric mean fold rise (95% confidence interval) 259 (219, 306); seroconversion rate 100% (97.6, 100). No such response occurred with placebo (n = 49).ConclusionTwo doses of NVX-CoV2373 given with a 21-day interval demonstrated acceptable safety and induced robust anti-SARS-CoV-2 immune responses in healthy Japanese adults. Funding: Takeda Pharmaceutical Company Limited and Japan Agency for Medical Research and Development (AMED). ClinicalTrials.gov identifier: NCT04712110.  相似文献   
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护理学科高质量发展促进公立医院高质量发展。介绍了陕西省人民医院以符合时代要求的护理管理、患者体验、人才队伍、学科建设、效率提升、文化建设为切入点的临床护理高质量发展“六新”模式,对实施成果进行总结分析,并从信息化建设角度思考如何进一步推进临床护理高质量发展,为推动临床护理高质量发展提供参考。  相似文献   
7.
人类遗传资源对推进生命科学研究和促进医药产业发展具有重要意义。随着精准医学战略的实施和基因编辑技术的不断成熟,各国对人类遗传资源的争夺及其相关科技发展和产业的竞争愈发激烈。经济合作与发展组织(OECD)作为最重要的国际经济组织,其指南的制定通常是围绕各国政府普遍关注的科学进步和科学效率问题,从国家和全球公共利益的角度出发,提出应对技术发展、科研范式变化的方案,近年来美国、日本和英国等发达国家也出台了相应的遗传资源数据共享政策和管理指南。本文旨在通过对OECD提出的人类遗传资源共享指南和以美国、英国、日本为代表的技术发达国家在实践中的管理要点进行分析,为提高中国人类遗传资源共享的监管效力,促进资源的合法共享和有效利用提供参考。  相似文献   
8.
《Pediatric Dental Journal》2019,29(3):116-122
ObjectiveInvestigation of dynamic occlusal contacts when food particles are being pulverized during chewing is of interest for many researchers and clinicians. However, measurement of dynamic occlusal contacts during chewing is difficult, and differences between children and adults have not been established. The purpose of this study is to test the hypothesis that dynamic occlusal contacts of children differ from those of adult females.Subjectsand methods: Thirteen healthy children (4–6 years of age; mean age 5 years, 7 months) and thirteen adult females (18–26 years of age; mean age 20 years, 7 months) with normal occlusion participated in this study. Occlusal contact area (OCA) was estimated with a developed measurement system combining 3-D digitization of tooth shape with 3-D tracking of mandibular movements (1) during the closing stroke, (2) at the maximum closing position (MCP), and (3) during the opening stroke. OCA at static maximum intercuspation (ICP) was also estimated.ResultsAt the MCP, the children's OCA was less than 76.4% of the contact area seen at the ICP. The timing of maximum OCA in children was shifted more towards the opening stroke compared with adults, and the OCA remained greater during opening in children than adults. The occurrence of the MCP was less stable in children than in adults, both between subjects and within subjects.ConclusionsWe conclude that both the amount of OCA and the pattern of occlusal contacts during the occlusal phase of chewing completely differ between children and adult females.  相似文献   
9.
BackgroundThe growing number of online nursing programs increased the demand to utilize interactive virtual patient learning systems in online nursing courses.PurposeTo develop and assess the validity of a tool named “Virtual Patient Learning System Evaluation Tool”.MethodsThis study was conducted in 2015–2017. The tool’s validity was determined through the assessment of content validity using an exploratory factor analysis on the data provided by 160 RN-BSN online nursing students.ResultsExploratory factor analysis was used to analyze four factors including: (a) communication (19%), (b) nursing care plan application (21%), (c) competency development using a virtual learning system (42%), and performance evaluation (4.5%). These factors explained 86.5% of the total variance, with a correlation coefficient ranging from 0.46 to .921 (p < .001). In this study, reliability was demonstrated by a Cronbach’s alpha coefficient of 0.973 indicating a reliable measure for this tool.ConclusionEvaluating the effectiveness of virtual learning systems will guide the online teaching pedagogies and the online nursing program development.  相似文献   
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