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   1437021篇
  免费   108144篇
  国内免费   2604篇
耳鼻咽喉   20619篇
儿科学   48710篇
妇产科学   38063篇
基础医学   202852篇
口腔科学   36862篇
临床医学   126972篇
内科学   291500篇
皮肤病学   30536篇
神经病学   116487篇
特种医学   56685篇
外国民族医学   673篇
外科学   219496篇
综合类   29164篇
现状与发展   4篇
一般理论   569篇
预防医学   107740篇
眼科学   32218篇
药学   104972篇
  2篇
中国医学   2602篇
肿瘤学   81043篇
  2019年   11591篇
  2018年   16092篇
  2017年   12067篇
  2016年   13400篇
  2015年   15406篇
  2014年   21645篇
  2013年   33258篇
  2012年   45997篇
  2011年   48829篇
  2010年   28830篇
  2009年   27412篇
  2008年   46784篇
  2007年   50039篇
  2006年   50003篇
  2005年   49272篇
  2004年   47850篇
  2003年   46274篇
  2002年   45211篇
  2001年   65283篇
  2000年   67467篇
  1999年   57768篇
  1998年   17205篇
  1997年   15547篇
  1996年   15716篇
  1995年   14840篇
  1994年   14024篇
  1993年   13024篇
  1992年   45461篇
  1991年   44304篇
  1990年   42954篇
  1989年   40822篇
  1988年   37605篇
  1987年   36870篇
  1986年   34355篇
  1985年   33108篇
  1984年   25245篇
  1983年   21339篇
  1982年   13190篇
  1981年   12084篇
  1980年   10811篇
  1979年   22066篇
  1978年   15653篇
  1977年   13255篇
  1976年   12340篇
  1975年   13143篇
  1974年   15212篇
  1973年   14548篇
  1972年   13283篇
  1971年   11983篇
  1970年   11259篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Advanced age has been associated with a wide range of defects in both the innate and adaptive immune systems including diminished specific antibody responses that increase the risk of invasive pneumococcal disease (IPD) and limit the effectiveness of vaccines. However, the elderly are a heterogeneous group and measures of overall frailty may be a better indicator of disease susceptibility (or vaccine response) than chronological age alone.  相似文献   
993.
994.
Neuroimaging has in recent years greatly contributed to our understanding of a wide range of aspects of central neurological diseases. These include the classification and localization of disease (e.g., in headache), the understanding of pathology (e.g., in Parkinson’s disease), mechanisms of reorganization (e.g., in stroke), and the subclinical progress of disease (e.g., in degenerative diseases). Apart form presurgical mapping, clinical applications of fMRI are limited. However, functional imaging enables the formulation of neurobiological hypotheses that can be tested clinically and is suited to test classical clinical hypotheses about how the brain works. Understanding the mechanisms and the site of pathology, e.g., in cluster headaches, will lead and has led to new therapeutic strategies. New methodological developments for neuroscientific applications are aimed at the integration of functional and morphological connectivity through a combination of magnetic resonance techniques (fMRI, DTI) and electrophysiological (EEG, MEG) recordings. In addition to stimulus-dependent activations, resting state activity has found increasing interest, for example, in sleep research and various psychiatric diseases (e.g., schizophrenia, borderline).  相似文献   
995.
996.
PURPOSE The purpose of this study was to examine the psychological effects of physical and verbal abuse in a cohort of older women.METHODS This observational cohort study was conducted at 40 clinical sites nationwide that are part of the Women’s Health Initiative (WHI) Observational Study. We surveyed 93,676 women aged 50 to 79 years using the mental health subscales and the combined mental component summary (MCS) score of the RAND Medical Outcomes Study 36-item instrument.RESULTS At baseline, women reporting exposure to physical abuse only, verbal abuse only, or both physical and verbal abuse had a greater number of depressive symptoms (1.6,1.6, and 3 more symptoms, respectively) and lower MCS scores (4.6, 5.4, and 8.1 lower scores, respectively) than women not reporting abuse. Compared with women who had no exposure to abuse, women had a greater increase in the number of depressive symptoms when they reported a 3-year incident exposure to physical abuse only (0.2; 95% confidence interval [CI], −0.21 to 0.60), verbal abuse only (0.18; 95% CI, 0.11 to 0.24), or both physical and verbal abuse (0.15; 95% CI, −0.05 to 0.36); and they had a decrease in MCS scores when they reported a 3-year incident exposure to physical abuse only (−1.12; 95% CI, −2.45 to 0.12), verbal abuse only (−0.55; 95% CI, −0.75 to −0.34), and both physical and verbal abuse (−0.44; 95% CI, −1.11 to −0.22) even after adjustment for sociodemographic characteristics.CONCLUSION Exposure to abuse in older, functionally independent women is associated with poorer mental health. The persistence of these findings suggests that clinicians need to consider abuse exposure in their older female patients who have depressive symptoms. Clinicians caring for older women should identify women at risk for physical and verbal abuse and intervene appropriately.  相似文献   
997.
Palliative whole brain radiotherapy (WBRT) is often recommended in the management of multiple brain metastases. Allowing for WBRT waiting time, duration of the WBRT course and time to clinical response, it may take 6 weeks from the point of initial assessment for a benefit from WBRT to manifest. Patients who die within 6 weeks (‘early death’) may not benefit from WBRT and may instead experience a decline in quality of life. This study aimed to develop a prognostic index (PI) that identifies the subset of patients with lung cancer with multiple brain metastases who may not benefit from WBRT because of ‘early death’. The medical records of patients with lung cancer who had WBRT recommended for multiple brain metastases over a 10-year period were retrospectively reviewed. Patients were classified as either having died within 6 weeks or having lived beyond 6 weeks. Potential prognostic indicators were evaluated for correlation with ‘early death’. A PI was constructed by modelling the survival classification to determine the contribution of these factors towards shortened survival. Of the 275 patients recommended WBRT, 64 (23.22%) died within 6 weeks. The main prognostic factor predicting early death was Eastern Cooperative Oncology Group (ECOG) status >2. Patients with a high PI score (>13) were at higher risk of ‘early death’. Twenty-three per cent of patients died prior to benefit from WBRT. ECOG status was the most predictive for ‘early death’. Other factors may also contribute towards a poor outcome. With further refinement and validation, the PI could be a valuable clinical decision tool.  相似文献   
998.
999.
1000.
Facial paralysis     
  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