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   1352篇
  免费   160篇
  国内免费   50篇
耳鼻咽喉   9篇
儿科学   49篇
妇产科学   4篇
基础医学   137篇
口腔科学   20篇
临床医学   197篇
内科学   330篇
皮肤病学   12篇
神经病学   124篇
特种医学   177篇
外科学   156篇
综合类   47篇
一般理论   1篇
预防医学   151篇
眼科学   11篇
药学   103篇
中国医学   1篇
肿瘤学   33篇
  2021年   13篇
  2020年   9篇
  2019年   17篇
  2018年   11篇
  2016年   10篇
  2015年   24篇
  2014年   31篇
  2013年   34篇
  2012年   49篇
  2011年   50篇
  2010年   50篇
  2009年   37篇
  2008年   50篇
  2007年   62篇
  2006年   51篇
  2005年   46篇
  2004年   38篇
  2003年   34篇
  2002年   30篇
  2001年   29篇
  2000年   41篇
  1999年   26篇
  1998年   55篇
  1997年   40篇
  1996年   49篇
  1995年   32篇
  1994年   25篇
  1993年   31篇
  1992年   35篇
  1991年   27篇
  1990年   21篇
  1989年   38篇
  1988年   46篇
  1987年   35篇
  1986年   30篇
  1985年   31篇
  1984年   24篇
  1983年   25篇
  1982年   20篇
  1981年   15篇
  1980年   20篇
  1979年   21篇
  1978年   29篇
  1977年   24篇
  1976年   16篇
  1975年   16篇
  1974年   16篇
  1973年   19篇
  1972年   16篇
  1927年   6篇
排序方式: 共有1562条查询结果,搜索用时 15 毫秒
1.
2.
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools.  相似文献   
3.
Sixteen patients receiving percutaneous endoscopic gastrostomy (PEG) feeding following a period of nasogastric (NG) feeding were investigated to assess acceptance and identify problems by means of a questionnaire. PEG was considered to be superior to NG feeding in terms of tolerance and cosmetic acceptance by 81% and 88% of participants respectively ( P < 0.001). Pain was an infrequent problem. Interruptions to feeding were consideed to be more common with NG feeding by 50% of participants; 38% considered interruptions equally common with both PEG and NG, and 12% considered interruptions more common with PEG feeding ( P = NS). The time for care was equivalent for both methods. Seventy-five percent considered PEG to have made a valuable contribution to enteral feeding. Leakage was however considered to be more frequent in PEG feeding by 81% of participants (compared to 12% who considered leakage to be more common with NG feeding; P < 0.001) and leakage was more frequent at die junctions in the catheter rather than from the stoma. Thirty-one percent of patients with PEG had needed systemic antibiotics for stomal infections. All patients with both PEG and NG feeding needed professional help. Sixty-two percent needed professional help more frequently with PEG than with NG feeding (compared to 19% who considered that the NG tube needed professional help more frequently; P <0.05). We conclude that leakage and infections are major problems in PEG enteral feeding.  相似文献   
4.
5.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.  相似文献   
6.
The purpose of this study was to investigate the histogenesis of experimental tumors in the rat esophagus. Thirty rats received 0.0015% N-methyl-N-amylnitrosamine (MNAN) in the drinking water for 12 weeks. Another 30 rats received tap water. All rats then received tap water until sacrifice. Rats from each group were sacrificed immediately after MNAN administration, four weeks after, and eight weeks after. One hour before sacrifice, [3H]TdR was injected by tail vein to label proliferating cells. The entire esophagus and stomach were removed and processed for light and electron microscopy and autoradiography. The overall frequency of esophageal tumors after MNAN was 83% and did not differ significantly among the three experimental groups. Tumors were primarily papillomas and squamous cell carcinomas and occurred with equal frequency in the upper, middle, and lower thirds of the esophagus. No tumors were found in the squamous-lined forestomach. Electron microscopy revealed abundant tonofilaments, free ribosomes, and mitochondria accompanied by vacuoles. By autoradiography, esophageal epithelial proliferation was markedly stimulated in nontumorous mucosa from all three experimental groups. We conclude that MNAN ingestion for 12 weeks reliably produces papillomas and squamous cell carcinomas throughout the rat esophagus, but not in the squamouslined forestomach, and that MNAN stimulated marked epithelial proliferation which is accompanied by thickening of the epithelium in nontumorus esophageal mucosa.  相似文献   
7.
8.
9.
10.
Abstract: Informal caregivers are the families and other unpaid caregivers in the home who support people of all ages with severe and chronic mental or physical disabilities. Home care of this sort has been increasing over the past 30 years because of the reduced number of beds in hospitals and nursing homes and increased outpatient and community care. Moreover, with an aging population and increasing rates of disability, the demand for family caregiving will continue to rise. This has important implications for the development of health, community service and social policy. At the same time, however, very little is known about the impact such changes are having on the caregivers of various ages and in various circumstances. The Victorian Health Promotion Foundation is funding a research and intervention program in Melbourne to promote wellbeing and prevent ill-health in caregivers.  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