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   235319篇
  免费   14890篇
  国内免费   989篇
耳鼻咽喉   2525篇
儿科学   5999篇
妇产科学   4415篇
基础医学   29368篇
口腔科学   4335篇
临床医学   24057篇
内科学   49599篇
皮肤病学   3222篇
神经病学   23702篇
特种医学   10114篇
外国民族医学   13篇
外科学   37022篇
综合类   2537篇
现状与发展   1篇
一般理论   177篇
预防医学   16525篇
眼科学   5533篇
药学   15483篇
  1篇
中国医学   319篇
肿瘤学   16251篇
  2023年   1335篇
  2022年   2192篇
  2021年   5334篇
  2020年   3044篇
  2019年   5052篇
  2018年   6048篇
  2017年   4443篇
  2016年   4848篇
  2015年   5734篇
  2014年   8347篇
  2013年   11245篇
  2012年   17280篇
  2011年   18014篇
  2010年   10073篇
  2009年   9315篇
  2008年   15872篇
  2007年   16667篇
  2006年   16198篇
  2005年   16053篇
  2004年   15107篇
  2003年   13792篇
  2002年   13188篇
  2001年   1944篇
  2000年   1439篇
  1999年   2010篇
  1998年   2792篇
  1997年   2220篇
  1996年   1928篇
  1995年   1766篇
  1994年   1531篇
  1993年   1494篇
  1992年   985篇
  1991年   932篇
  1990年   788篇
  1989年   756篇
  1988年   688篇
  1987年   614篇
  1986年   637篇
  1985年   683篇
  1984年   914篇
  1983年   787篇
  1982年   1035篇
  1981年   971篇
  1980年   837篇
  1979年   464篇
  1978年   514篇
  1977年   447篇
  1976年   421篇
  1975年   314篇
  1974年   310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