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   93906篇
  免费   29018篇
  国内免费   1064篇
耳鼻咽喉   2398篇
儿科学   2505篇
妇产科学   2315篇
基础医学   1975篇
口腔科学   5031篇
临床医学   25502篇
内科学   23663篇
皮肤病学   3227篇
神经病学   11785篇
特种医学   3476篇
外科学   17458篇
综合类   106篇
现状与发展   40篇
预防医学   13012篇
眼科学   2085篇
药学   817篇
中国医学   5篇
肿瘤学   8588篇
  2024年   739篇
  2023年   5001篇
  2022年   1057篇
  2021年   2628篇
  2020年   5253篇
  2019年   1911篇
  2018年   6773篇
  2017年   7241篇
  2016年   7820篇
  2015年   7893篇
  2014年   10260篇
  2013年   11904篇
  2012年   3448篇
  2011年   3175篇
  2010年   6626篇
  2009年   8934篇
  2008年   3195篇
  2007年   2138篇
  2006年   3306篇
  2005年   1880篇
  2004年   1274篇
  2003年   974篇
  2002年   898篇
  2001年   1784篇
  2000年   1108篇
  1999年   1649篇
  1998年   2039篇
  1997年   1871篇
  1996年   1929篇
  1995年   1666篇
  1994年   1065篇
  1993年   896篇
  1992年   729篇
  1991年   616篇
  1990年   494篇
  1989年   504篇
  1988年   489篇
  1987年   366篇
  1986年   342篇
  1985年   285篇
  1984年   243篇
  1983年   292篇
  1982年   219篇
  1981年   192篇
  1980年   116篇
  1978年   119篇
  1977年   114篇
  1976年   83篇
  1974年   70篇
  1972年   71篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Background: The bariatric patient exists in dynamic relationship with family members and friends who have considerable influence upon the patient and his or her surgical outcome. When family members and friends behave as intimate saboteurs, they attempt to hamper, hurt, or subvert the bariatric patient's goal of achieving and maintaining a healthy body weight. Successful or not, intimate saboteurs provide significant treatment challenges for the patient and the treatment team. Methods and Patients: Patient profiles provide examples of intimate sabotage. The psychological construct of Family Systems Theory is used as a plausible explanation for the sabotage of friends and family. Conclusions: Multidisciplinary professionals treating the bariatric patient must be aware of the critical influence of intimate saboteurs and the tactics they use to sabotage. Treatment guidelines recommended by Family Systems Theory are presented as strategies to mitigate the influence of intimate saboteurs.  相似文献   
42.
Society often expects mothers and fathers to share equally in the perinatal grief process because the child was a common bond between them. Unfortunately, in perinatal grief, this is not always the case. The mother and the father can experience incongruent grieving and use discordant coping mechanisms. It is important to evaluate these differences to facilitate communication between the distraught parents. Improved communication can in turn facilitate the grieving process.  相似文献   
43.
44.
45.
46.
The action of papain and bromelain, prepared over a pH range from 4.6 to 8.6, was evaluated for the ability to render red cells agglutinable by five incomplete antibodies of differing blood group specificities using a two-stage technique. The optimal pH for treatment of red cells by activated papain or bromelain was between 5.4 and 5.8. Above this pH range, a fall in serological sensitivity was apparent which was much more pronounced with papain than with bromelain. The optimal pH for enzyme treatment of red cells can be achieved in two-stage techniques, but not in one-stage techniques due to the buffering effect of serum proteins.  相似文献   
47.
This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost.  相似文献   
48.
Directors of nursing at 23 nursing homes with Alzheimer's units in Southwestern Pennsylvania completed a self‐reported survey of 12 questions. Responses from the self‐administered questionnaires (100% response rate) revealed a wide variation in the staff categories assessing the oral health status of newly admitted residents with AD. The respondents described oral examinations that were incomplete when compared to the oral indicators listed in the Minimum Data Set. All nursing homes reported that oral hygiene was provided each day. The number of residents in a facility had a significant effect on the frequency of oral hygiene provided. Only 52% of the facilities reported yearly oral examinations for this population. According to the respondents, dental treatment was typically performed on‐site. The oral health care costs were paid by Medicare, Medicaid, the residents/family members, or by other undescribed resources. Insufficient time, staff, and training, as well as uncooperative behavior, were identified as barriers to optimum oral health care for residents with AD. Additional staff, specialized training, and increased government reimbursement were suggested to improve the oral health care for this group of older adults. For future studies, review of medical records and on‐site evaluation of the oral health care at these facilities should be required to verify the reported practices.  相似文献   
49.
50.
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