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   235463篇
  免费   14897篇
  国内免费   989篇
耳鼻咽喉   2529篇
儿科学   5993篇
妇产科学   4418篇
基础医学   29337篇
口腔科学   4321篇
临床医学   24093篇
内科学   49608篇
皮肤病学   3230篇
神经病学   23662篇
特种医学   10123篇
外国民族医学   13篇
外科学   37107篇
综合类   2538篇
现状与发展   1篇
一般理论   178篇
预防医学   16569篇
眼科学   5541篇
药学   15499篇
  1篇
中国医学   320篇
肿瘤学   16268篇
  2023年   1337篇
  2022年   2198篇
  2021年   5337篇
  2020年   3046篇
  2019年   5056篇
  2018年   6060篇
  2017年   4447篇
  2016年   4854篇
  2015年   5741篇
  2014年   8356篇
  2013年   11267篇
  2012年   17306篇
  2011年   18022篇
  2010年   10080篇
  2009年   9328篇
  2008年   15880篇
  2007年   16670篇
  2006年   16214篇
  2005年   16069篇
  2004年   15120篇
  2003年   13797篇
  2002年   13191篇
  2001年   1933篇
  2000年   1433篇
  1999年   2018篇
  1998年   2787篇
  1997年   2214篇
  1996年   1925篇
  1995年   1765篇
  1994年   1529篇
  1993年   1493篇
  1992年   981篇
  1991年   926篇
  1990年   790篇
  1989年   747篇
  1988年   680篇
  1987年   620篇
  1986年   636篇
  1985年   679篇
  1984年   913篇
  1983年   787篇
  1982年   1035篇
  1981年   965篇
  1980年   837篇
  1979年   464篇
  1978年   515篇
  1977年   448篇
  1976年   419篇
  1975年   316篇
  1974年   312篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
The literature suggests that pain in the elderly, especially among seniors with dementia, is under-assessed and under-treated.This qualitative study solicited the perspectives of seniors, front-line nursing staff, nursing-home administrators, and informal caregivers of seniors with dementia on the current status of pain assessment and management. The views of these participants complement the research findings reported in the literature. While some of their explanations and potential solutions concerning under-treatment of pain in seniors echo views that have been presented in the literature, the participants also pointed to factors and avenues that have been given less formal consideration (e.g., systemic barriers to effective assessment and treatment of pain).They also highlighted the need for pain-control strategies beyond medication. The implications of these findings are discussed.  相似文献   
53.
Metabolic syndrome is associated with increased risk for cardiovascular and cerebrovascular disease. The World Health Organization and National Cholesterol Education Program Adult Treatment Panel III have identified physiologic abnormalities associated with metabolic syndrome, including impaired glucose metabolism, high blood pressure, elevated cholesterol levels, and abdominal obesity. It is estimated that 47 million Americans have metabolic syndrome. A variety of therapies may help reduce the incidence and risk, including diet, weight loss, physical exercise, glycemic control, and pharmacological treatments. Nursing care is focused on developing an individualized plan of care that includes family members and providing education, psychosocial support, close monitoring, and continued follow-up to ensure adherence and success in achieving patient outcomes.  相似文献   
54.
55.
56.
PURPOSE: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor, increases survival when combined with irinotecan-based chemotherapy in first-line treatment of metastatic colorectal cancer (CRC). This randomized, phase II trial compared bevacizumab plus fluorouracil and leucovorin (FU/LV) versus placebo plus FU/LV as first-line therapy in patients considered nonoptimal candidates for first-line irinotecan. PATIENTS AND METHODS: Patients had metastatic CRC and one of the following characteristics: age > or = 65 years, Eastern Cooperative Oncology Group performance status 1 or 2, serum albumin < or = 3.5 g/dL, or prior abdominal/pelvic radiotherapy. Patients were randomly assigned to FU/LV/placebo (n = 105) or FU/LV/bevacizumab (n = 104). The primary end point was overall survival. Secondary end points were progression-free survival, response rate, response duration, and quality of life. Safety was also assessed. RESULTS: Median survival was 16.6 months for the FU/LV/bevacizumab group and 12.9 months for the FU/LV/placebo group (hazard ratio, 0.79; P = .16). Median progression-free survival was 9.2 months (FU/LV/bevacizumab) and 5.5 months (FU/LV/placebo); hazard ratio was 0.50; P = .0002. Response rates were 26.0% (FU/LV/bevacizumab) and 15.2% (FU/LV/placebo) (P = .055); duration of response was 9.2 months (FU/LV/bevacizumab) and 6.8 months (FU/LV/placebo); hazard ratio was 0.42; P = .088. Grade 3 hypertension was more common with bevacizumab treatment (16% v 3%) but was controlled with oral medication and did not cause study drug discontinuation. CONCLUSION: Addition of bevacizumab to FU/LV as first-line therapy in CRC patients who were not considered optimal candidates for first-line irinotecan treatment provided clinically significant patient benefit, including statistically significant improvement in progression-free survival.  相似文献   
57.
58.
The most important physiological parameter influencing tissue response to heat is blood flow. At mild hyperthermia temperatures blood perfusion increases in many tumours and this effect is heating time-, temperature- and tumour-dependent. These flow increases can improve tumour oxygenation. When heating is terminated, perfusion and oxygenation commonly recover, although how quickly this occurs appears to be tumour-specific. While these effects are unlikely to have any anti-tumour activity they can be exploited to improve the combination of heat with other therapies. However, since similar physiological effects should occur in normal tissues, such combination therapies must be carefully applied. Heating tumours to higher temperatures typically causes a transient increase in perfusion during heating, followed by vascular collapse which if sufficient will increase tumour necrosis. The speed and degree of vascular collapse is dependent on heating time, temperature and tumour model used. Such vascular collapse generally occurs at temperatures that cause a substantial blood flow increase in certain normal tissues, thus preferential anti-tumour effects can be achieved. The tumour vascular supply can also be exploited to improve the response to heat. Decreasing blood flow, using transient physiological modifiers or longer acting vascular disrupting agents prior to the initiation of heating, can both increase the accumulation of physical heat in the tumour, as well as increase heat sensitivity by changing the tumour micro-environmental parameters, primarily an increase in tumour acidity. Such changes are generally not seen in normal tissues, thus resulting in a therapeutic benefit.  相似文献   
59.
60.
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