首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   237385篇
  免费   8062篇
  国内免费   4965篇
耳鼻咽喉   1601篇
儿科学   7461篇
妇产科学   3696篇
基础医学   22903篇
口腔科学   2724篇
临床医学   20813篇
内科学   39027篇
皮肤病学   1121篇
神经病学   19258篇
特种医学   11180篇
外国民族医学   40篇
外科学   34338篇
综合类   15224篇
现状与发展   24篇
一般理论   3篇
预防医学   22942篇
眼科学   4217篇
药学   16714篇
  90篇
中国医学   5568篇
肿瘤学   21468篇
  2024年   273篇
  2023年   1185篇
  2022年   2745篇
  2021年   3861篇
  2020年   2966篇
  2019年   2395篇
  2018年   24126篇
  2017年   19598篇
  2016年   21546篇
  2015年   4220篇
  2014年   4684篇
  2013年   4290篇
  2012年   12071篇
  2011年   26386篇
  2010年   22540篇
  2009年   14731篇
  2008年   22977篇
  2007年   24916篇
  2006年   3640篇
  2005年   4927篇
  2004年   5264篇
  2003年   6120篇
  2002年   3956篇
  2001年   1584篇
  2000年   1632篇
  1999年   1319篇
  1998年   894篇
  1997年   844篇
  1996年   638篇
  1995年   629篇
  1994年   508篇
  1993年   312篇
  1992年   337篇
  1991年   362篇
  1990年   338篇
  1989年   245篇
  1988年   221篇
  1987年   176篇
  1986年   124篇
  1985年   110篇
  1984年   58篇
  1983年   56篇
  1982年   47篇
  1980年   50篇
  1970年   23篇
  1938年   60篇
  1937年   25篇
  1934年   30篇
  1932年   56篇
  1930年   46篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
Farnesyltransferase (FTase) is one of the prenyltransferase family enzymes that catalyse the transfer of 15-membered isoprenoid (farnesyl) moiety to the cysteine of CAAX motif-containing proteins including Rho and Ras family of G proteins. Inhibitors of FTase act as drugs for cancer, malaria, progeria and other diseases. In the present investigation, we have developed two structure-based pharmacophore models from protein–ligand complex (3E33 and 3E37) obtained from the protein data bank. Molecular dynamics (MD) simulations were performed on the complexes, and different conformers of the same complex were generated. These conformers were undergone protein–ligand interaction fingerprint (PLIF) analysis, and the fingerprint bits have been used for structure-based pharmacophore model development. The PLIF results showed that Lys164, Tyr166, TrpB106 and TyrB361 are the major interacting residues in both the complexes. The RMSD and RMSF analyses on the MD-simulated systems showed that the absence of FPP in the complex 3E37 has significant effect in the conformational changes of the ligands. During this conformational change, some interactions between the protein and the ligands are lost, but regained after some simulations (after 2 ns). The structure-based pharmacophore models showed that the hydrophobic and acceptor contours are predominantly present in the models. The pharmacophore models were validated using reference compounds, which significantly identified as HITs with smaller RMSD values. The developed structure-based pharmacophore models are significant, and the methodology used in this study is novel from the existing methods (the original X-ray crystallographic coordination of the ligands is used for the model building). In our study, along with the original coordination of the ligand, different conformers of the same complex (protein–ligand) are used. It concluded that the developed methodology is significant for the virtual screening of novel molecules on different targets.  相似文献   
22.
23.
Platelet function has been described by many laboratory assays, and PL-11 is a new point-of-care platelet function analyzer based on platelet count drop method, which counts platelet before and after the addition of agonists in the citrated whole blood samples. The present study sought to compare PL-11 with other three major more established assays, light transmission aggregometry (LTA), VerifyNow? aspirin system and thromboelastography (TEG), for monitoring the short-term aspirin responses in healthy individuals. Ten healthy young men took 100?mg/d aspirin for 3-day treatment. Platelet function was measured via PL-11, LTA, VerifyNow and TEG, respectively. The blood samples were collected at baseline, 2 hour, 1 day during the aspirin treatment and 1 day, 5?±?1 days, 8?±?1 days after the aspirin withdrawal. Moreover, 90 additional healthy subjects were recruited to establish a reference range for PL-11. Platelet function of healthy subjects decreased significantly 2 hours after 100?mg/d aspirin intake and began to recover during 4–6 days after the aspirin withdrawal. Correlations between methods were PL-11 vs. LTA (r?=?0.614, p?<?0.01); PL-11 vs. VerifyNow (r?=?0.829, p?<?0.01); PL-11 vs. TEG (r?=?0.697, p?<?0.001). There was no significant bias between PL-11 and LTA at baseline (bias?=?1.94%, p?=?0.804) using Bland-Altman analysis, while the data of PL-11 were significantly higher than LTA (bias?=?24.02%, p?<?0.001) during the aspirin therapy. The reference range for PL-11 in healthy young individuals was from 66.8 to 90.5% (95%CI). When aspirin low-responsiveness was defined as LTA?>?20%, the cut-off values for each method were, respectively: PL-11?>?50%, VerifyNow?>?533 ARU, TEG?>?60.2%. The results of different platelet function assays were uninterchangeable for monitoring aspirin response and correlations among them were also varied. Correlations among PL-11 and other three major assays suggested the ability of PL-11 to assess the treatment effects of aspirin. But a large cohort study is needed to confirm the cut-off value of aspirin response detected by PL-11.  相似文献   
24.
This paper takes a somewhat slant perspective on flourishing and care in the context of suffering, death and dying, arguing that care in this context consists principally of ‘acts of work and courage that enable flourishing’. Starting with the perception that individuals, society and health care professionals have become dulled to death and the process of dying in Western advanced health systems, it suggests that for flourishing to occur, both of these aspects of life need to be faced more directly. The last days of life need to be ‘undulled’. Reflections upon the experiences of the author as carer and daughter in the face of her mother’s experience of death are used as basis for making suggestions about how care systems and professionals might better assist people in dealing with ‘the most grown up thing’ humans ever do, which is to die.  相似文献   
25.
26.
目的 通过对公开发表在网络和数据库的有关中医药治疗2019新型冠状病毒肺炎(corona virus disease 2019,COVID-19)的文献进行方、药、证的可视化分析,客观全面的对COVID-19的中医药治疗进行探讨,为现代中医临床诊疗提供参考。方法 本文选用运用文献计量学方法和VOSviewer可视化软件对纳入文献中的用药情况进行数据拆分、整理和分析。结果 本研究高质量数据的主要期刊来源是核心期刊《中医杂志》;新冠临床用方以解表清热剂、开窍补益剂、辟秽祛湿剂为主;临床用药以解表药、清热解毒药、化湿祛痰药以及补益药为主;临床治病思路以六经辨证、三焦辨证和卫气营血辨证理论为指导;临床常见证型为湿、热、寒、毒相关证型;重视新冠前期预防以及后期恢复调养;治疗过程用药考究,注重养阴与祛邪并进。结论 新冠的中医临床诊治考病全面,并注重养阴与祛邪并进,可为官方制定治疗方案提供参考。  相似文献   
27.
综述护士个人-组织契合度的概念、评估工具以及现状,通过分析影响护士个人-组织契合度的因素,明确提高护士个人-组织契合度的策略,以期为护理管理者改善护士工作环境,构建良好稳固的护理队伍提供参考.  相似文献   
28.
Advancing nanomedicines from concept to clinic requires integration of new science with traditional pharmaceutical development. The medical and commercial success of nanomedicines is greatly facilitated when those charged with developing nanomedicines are cognizant of the unique opportunities and technical challenges that these products present. These individuals must also be knowledgeable about the processes of clinical and product development, including regulatory considerations, to maximize the odds for successful product registration. This article outlines these topics with a goal to accelerate the combination of academic innovation with collaborative industrial scientists who understand pharmaceutical development and regulatory approval requirements—only together can they realize the full potential of nanomedicines for patients.  相似文献   
29.
30.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号