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   58285篇
  免费   5019篇
  国内免费   197篇
耳鼻咽喉   532篇
儿科学   1923篇
妇产科学   1538篇
基础医学   8614篇
口腔科学   838篇
临床医学   8401篇
内科学   11156篇
皮肤病学   1257篇
神经病学   6301篇
特种医学   1347篇
外国民族医学   4篇
外科学   5479篇
综合类   579篇
现状与发展   1篇
一般理论   39篇
预防医学   6085篇
眼科学   894篇
药学   3803篇
中国医学   60篇
肿瘤学   4650篇
  2023年   518篇
  2022年   792篇
  2021年   1616篇
  2020年   1173篇
  2019年   1793篇
  2018年   2051篇
  2017年   1601篇
  2016年   1724篇
  2015年   1811篇
  2014年   2397篇
  2013年   3174篇
  2012年   4586篇
  2011年   4578篇
  2010年   2633篇
  2009年   2384篇
  2008年   3885篇
  2007年   3942篇
  2006年   3592篇
  2005年   3590篇
  2004年   3274篇
  2003年   2999篇
  2002年   2802篇
  2001年   459篇
  2000年   336篇
  1999年   507篇
  1998年   633篇
  1997年   509篇
  1996年   387篇
  1995年   383篇
  1994年   323篇
  1993年   294篇
  1992年   210篇
  1991年   201篇
  1990年   182篇
  1989年   181篇
  1988年   155篇
  1987年   123篇
  1986年   134篇
  1985年   125篇
  1984年   137篇
  1983年   118篇
  1982年   133篇
  1981年   140篇
  1980年   108篇
  1979年   62篇
  1978年   65篇
  1977年   80篇
  1976年   80篇
  1975年   56篇
  1974年   62篇
排序方式: 共有10000条查询结果,搜索用时 19 毫秒
71.
A brief overview is provided of the bioactivity of macrolides against a range of bacterial species. Topics considered include the cellular pharmacokinetics of uptake and efflux of these drugs and the importance of intra- or extracellular and cytoplasmic or granular location on their activity. Emphasis is placed on the importance of synergy between macrolides and host defenses, with drug accumulation producing modification of cellular function, such as enhancement of phagocytosis, and exocytosis of polymorphonuclear neutrophils. Such interaction may explain the activity of such agents against organisms which normally inhibit fusion of phagolysosomes.  相似文献   
72.
Summary This study was carried out in order: (1) to examine the effects of isolated and combined prolonged exposures to noise and whole-body vibration on hearing, vision and subjectively experienced strain, and (2) to check the combined effects with repeated exposures. Six male subjects were exposed twice to noise (N) at 92 dBA, whole-body vibration (V) in the Z-axis at 4 Hz and 1.0 ms–2 rms, and noise and vibration (NV) for 90 min with each condition. Temporary threshold shifts of hearing (TTS) and their integrals (ITTS) were measured at 4, 6, 10, and 12 kHz. Visual acuity was examined by means of a very sensitive test. Cross-modality matching (CMM) of the handgrip force was used to judge the subjectively experienced strain. NV induced a clear tendency of higher TTS and ITTS than N, with several significant differences most pronounced at 10 kHz. With repeated exposures, the effect of NV decreased, while the reactions to N and V remained unchanged. The individual reactions to NV differed. The influence of the duration of exposures on vision depended on the condition; N caused time-dependent changes, whereas V did not. CMM-data increased with the duration of the exposure during V and NV. N was generally judged to be more straining than V; NV caused higher strain than V during the first 30 min of exposure only. Correlations between different effects suggest certain links between them. Additionally, less motivation — daily obtained by a questionnaire — often correlated with higher ITTS during N and NV. The results also illustrate the combined effects on the individual susceptibility, repetition of exposure, the kind of response, and, possibly, the actual psychic state.Abbreviations CMM cross-modality matching - MVC maximum voluntary contraction force - N exposure condition: noise level 92dBA, no whole-body vibration - NV exposure condition: combined exposure to noise with a level of 92 dBA and wholebody vibration with 4 Hz, 1 ms–2 rms - V exposure condition: whole-body vibration with 4 Hz, 1 ms–2 rms - TTS temporary threshold shift - ITTS integral of temporary threshold shift - WBV whole-body vibration in the common sense This work was done in the Temporary International Research Team on Combined Effects of Noise and Vibration of the Council of Mutual Economic Assistance of the Socialist Countries. The authors gratefully acknowledge the help and assistance of L.-M. Brumm, Y. Bening, M. Godau, G. Weber, and R. Vizcaino.  相似文献   
73.
Executive and compensatory memory retraining in traumatic brain injury   总被引:3,自引:0,他引:3  
A controlled treatment outcome study was conducted comparing the efficacy of memory remediation treatment with no treatment on traumatic brain-injury patients. The memory remediation treatment consisted of both compensatory and executive training skills and was delivered 6 hours weekly over a 2 1/2-week period. Six subjects in the treatment group and 6 subjects in the control group were matched on WAIS-R FSIQ scores, pre-test memory scores and age. Pre-and post-test measures were obtained for both groups on a paragraph memory task. A significant difference was demonstrated between the treatment and control post-test memory scores. The experimental group significantly improved memory scores beyond that of the control group, suggesting that memory remediation is effective for head-injury patients with memory deficits. Discussion of findings and suggestions for further investigation are presented.  相似文献   
74.
75.
The rapid movement of information technologies into health care organizations has raised managerial concern regarding the capability of today's institutions to satisfactorily manage their introduction. Indeed, several health care institutions have consumed huge amounts of money and frustrated countless people in wasted information systems implementation efforts. Unfortunately, there are no easy answers as to why so many health informatics projects are not more successful. In this light, the aim of this study is to provide a deeper understanding of how clinical information systems are being implemented by emphasizing research efforts on the dynamic nature of the process, that is, the “how” and “why” of what happened. Using a case study methodology, we examined the implementation of a patient charting system in the Burn Center of a large, not-for-profit, teaching hospital. Based on an in-depth examination of this implementation, several insights are offered to those who have responsibility for managing complex and risky clinical information system implementation projects.  相似文献   
76.
77.
78.
Why should depression screening be conducted in chronically ill populations? Depression is a disabling illness and is very common among patients who have chronic illnesses. Despite its high prevalence in this patient population, depression often goes unrecognized. Having a plan for a population-based screening program for depression can not only identify patients who are at risk of depression, but can also help to foster early treatment and enhanced care for these patients. This article provides an overview of commonly-used depression screening tools and presents an example of how this might be carried out in a healthcare organization.  相似文献   
79.
The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.  相似文献   
80.
Explanations of cancer need to take into account developmental changes in children's cognitive and emotional abilities to understand illness. Children below 5 years of age are usually informed by parents, and older children by medical staff. Information tends to focus on details of treatments and procedures, and less on the seriousness of the disease and length of time involved. There are indications that early and honest information is associated with better behaviour and adjustment in the child, communication within the family and compliance with treatment, although methodological inadequacies in assessment of adjustment and knowledge of cancer limit the ability to generalize these findings. Communication with children should take into account developmental changes in children's ability to understand illness information. Communicators should also provide emotional support to deal with the threatening nature of this information.  相似文献   
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