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   1944篇
  免费   127篇
  国内免费   3篇
耳鼻咽喉   8篇
儿科学   88篇
妇产科学   47篇
基础医学   283篇
口腔科学   23篇
临床医学   202篇
内科学   374篇
皮肤病学   34篇
神经病学   180篇
特种医学   28篇
外科学   116篇
综合类   18篇
一般理论   1篇
预防医学   294篇
眼科学   47篇
药学   92篇
中国医学   1篇
肿瘤学   238篇
  2023年   21篇
  2022年   22篇
  2021年   38篇
  2020年   28篇
  2019年   66篇
  2018年   71篇
  2017年   27篇
  2016年   34篇
  2015年   65篇
  2014年   72篇
  2013年   113篇
  2012年   136篇
  2011年   142篇
  2010年   75篇
  2009年   81篇
  2008年   138篇
  2007年   135篇
  2006年   131篇
  2005年   123篇
  2004年   119篇
  2003年   94篇
  2002年   76篇
  2001年   23篇
  2000年   13篇
  1999年   18篇
  1998年   23篇
  1997年   21篇
  1996年   11篇
  1995年   14篇
  1994年   13篇
  1993年   12篇
  1992年   7篇
  1991年   11篇
  1990年   6篇
  1989年   7篇
  1988年   5篇
  1987年   3篇
  1986年   4篇
  1985年   7篇
  1984年   5篇
  1983年   6篇
  1982年   8篇
  1981年   7篇
  1980年   8篇
  1978年   6篇
  1976年   6篇
  1975年   3篇
  1974年   3篇
  1973年   3篇
  1918年   2篇
排序方式: 共有2074条查询结果,搜索用时 15 毫秒
91.
OBJECTIVE: There is a need for a brief, efficient depression screening measure for general practice settings, particularly for identifying those who are at high risk of depression. We therefore test the usefulness of a measure developed in a sample of medically ill hospitalized patients. METHOD: More than 600 patients attending six Sydney general practices completed the Depression in the Medically Ill (DMI-10) measure, in conjunction with sociodemographic, depression history and personality profile measures. The impacts of sociodemographic, personality and lifetime depression variables on DMI-10 scores (and identified 'cases') were examined as a measure of its usefulness. RESULTS: Gender did not influence depression scores, while there were slight associations between DMI-10 scores and age, marital and occupational status. Higher scores were returned by those with more severe, lengthier and perceived stressful medical illnesses. Using a predetermined cut-off score, 36% rated as putative 'cases', a prevalence almost identical to our general hospital study. 'Cases' were distinctly more likely to have had previous depressive episodes, to have sought help for such episodes and to have received antidepressant medication. They also scored higher on measures of anxious (anxious worrying and irritability) and self-critical ('depressive personality') personality styles. CONCLUSIONS: The DMI-10 appears useful as a brief and acceptable screen for depression in a general practice setting, both identifying those who are likely to be currently depressed and those with a background of previous depression.  相似文献   
92.
93.
The aim of this uncontrolled, prospective, clinical study was to investigate the efficacy and safety of molgramostim administration in patients with severe sepsis. The subjects were 20 critically ill, mechanically ventilated patients with severe sepsis in a university intensive care unit (ICU). Molgramostim 300 microg s.c. was given every 12 h for 3 d. Treatment for severe sepsis was also administered as medically indicated. No adverse events (clinical or serum chemistry) were considered as drug related. Temperature (p = 0.334) and PaO2/FiO2 index (arterial oxygen tension/inspiratory oxygen fraction) (p = 0.178) were not significantly changed. Total leukocyte and neutrophil count increased significantly (p < 0.001) during drug administration. Simplified Acute Physiology Score II (SAPS II) was not significantly increased (p = 0.955), but there was a statistically significant decrease (p = 0.006) in Sepsis-related Organ Failure Assessment (SOFA) score. Death probability was not statistically different compared with mortality rate on day 28 and overall mortality (p = 0.238 and 0.700, respectively). There were statistically significant decreases (p < 0.01) in serum tumor necrosis factor-alpha (TNF-alpha), TNF-RII and interleukin-2 (IL-2), and an increase in TNF-RI levels between study entry and day 3. Mean ICU stay was 40.2 +/- 7.7 d. In conclusion, molgramostim administration may not affect serum chemistry and PaO2/FiO2 index, may decrease SOFA score but does not produce significant clinical benefit in terms of patients' outcome compared with death probability. It may also influence TNF-alpha, TNF-RI and TNF-RII serum complex levels. These changes may be attributed to the natural clinical course of sepsis or therapy applied.  相似文献   
94.
Protein kinase C (PKC) beta isoform activity is increased in myocardium of diabetic rodents and heart failure patients. Transgenic mice overexpressing PKCbeta2 (PKCbeta2Tg) in the myocardium exhibit cardiomyopathy and cardiac fibrosis. In this study, we characterized the expression of connective tissue growth factor (CTGF) and transforming growth factor beta (TGFbeta) with the development of fibrosis in heart from PKCbeta2Tg mice at 4-16 weeks of age. Heart-to-body weight ratios of transgenic mice increased at 8 and 12 weeks, indicating hypertrophy, and ratios did not differ at 16 weeks. Collagen VI and fibronectin mRNA expression increased in PKCbeta2Tg hearts at 4-12 weeks. Histological examination revealed myocyte hypertrophy and fibrosis in 4- to 16-week PKCbeta2Tg hearts. CTGF expression increased in PKCbeta2Tg hearts at all ages, whereas TGFbeta increased only at 8 and 12 weeks. In 8-week diabetic mouse heart, CTGF and TGFbeta expression increased two- and fourfold, respectively. Similarly, CTGF expression increased in rat hearts at 2-8 weeks of diabetes. This is the first report of increased CTGF expression in myocardium of diabetic rodents suggesting that cardiac injury associated with PKCbeta2 activation, diabetes, or heart failure is marked by increased CTGF expression. CTGF could act independently or together with other cytokines to induce cardiac fibrosis and dysfunction.  相似文献   
95.
96.
BACKGROUND: Practicing primary care physicians often encounter the difficult clinical situation of evaluating the older driver. We wanted to investigate the relation between self-reported driving behavior, neuropsychological measures, and crash risk to inform the development of a test battery that could predict unsafe driving behavior and was feasible for use by primary care physicians. METHODS: This study was a prospective follow-up of 107 drivers aged 65 years and older recruited from a primary care setting in 1995. Tests of attention, visual information processing, spatial orientation, and general mental status were administered at baseline. At baseline and after 2 years of follow-up, patients were asked about their driving history using the driving questionnaire. Risk for reported crashes in the follow-up period was assessed in relation to baseline driving history and measures of cognition. RESULTS: Baseline self-reports of driving habits and attitudes were associated with an increased risk of reporting a crash after 2 years of follow-up (relative risk ratio = 5.31; 95% confidence interval [CI], 0.63, 44.63). In addition, baseline tests of attention, visual information processing, and spatial orientation were associated with an increased risk of reporting motor vehicle crash at follow-up. For example, respondents with poor performance on the Trail Making Test-part A, were almost four times more likely to report a crash at follow-up (risk ratio = 3.15; 95% CI, 0.76, 13.07). CONCLUSION: Although our conclusions are tempered by small sample size, this preliminary study suggests that brief cognitive tests and simple questions about driving habits warrant further investigation as indicators of crash risk with potential utility for assessing older drivers in primary care.  相似文献   
97.
Immunity or tolerance are determined through the bone marrow-derived, antigen-presenting cells, dendritic cells (DC). Stimulation of lymphocytes by different types of DC, DC at different stages of maturity and DC producing and responding to different growth factors modulate immune responses. Innate receptors for foreign or self antigens provide scope in DC for discrimination between different antigenic stimuli. DC also transfer processed antigens to other DC. We propose that DC do not stimulate responses to antigens in their own environment but only to antigens acquired from other DC, providing a mechanism for discriminating between environmental and non-environmental antigens.  相似文献   
98.
99.
100.
Women's perceptions of breast cancer risk are largely inaccurate and are often associated with high levels of anxiety about cancer. There are interesting cultural differences that are not well researched. Genetic risk counselling significantly improves accuracy of women's perceptions of risk, but not necessarily to the correct level. Reasons for this are unclear, but may relate to personal beliefs about susceptibility and to problems or variations in risk communication. Research into the impact of demographic and psychological factors on risk perception has been inconclusive. An understanding of the process of developing a perception of risk would help to inform risk counselling strategies. This is important, because knowledge of risk is needed both for appropriate health care decision making and to reassure women who are not at increased risk.  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