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   14622篇
  免费   968篇
  国内免费   76篇
耳鼻咽喉   217篇
儿科学   442篇
妇产科学   301篇
基础医学   1997篇
口腔科学   219篇
临床医学   1479篇
内科学   3473篇
皮肤病学   297篇
神经病学   1343篇
特种医学   393篇
外国民族医学   7篇
外科学   1822篇
综合类   109篇
一般理论   9篇
预防医学   1292篇
眼科学   182篇
药学   1056篇
中国医学   25篇
肿瘤学   1003篇
  2023年   121篇
  2022年   212篇
  2021年   440篇
  2020年   264篇
  2019年   396篇
  2018年   465篇
  2017年   304篇
  2016年   375篇
  2015年   437篇
  2014年   547篇
  2013年   696篇
  2012年   1117篇
  2011年   1115篇
  2010年   624篇
  2009年   540篇
  2008年   896篇
  2007年   873篇
  2006年   920篇
  2005年   827篇
  2004年   698篇
  2003年   696篇
  2002年   622篇
  2001年   163篇
  2000年   169篇
  1999年   158篇
  1998年   137篇
  1997年   103篇
  1996年   93篇
  1995年   76篇
  1994年   70篇
  1993年   54篇
  1992年   113篇
  1991年   110篇
  1990年   77篇
  1989年   80篇
  1988年   67篇
  1987年   99篇
  1986年   78篇
  1985年   98篇
  1984年   59篇
  1983年   57篇
  1982年   41篇
  1981年   42篇
  1980年   37篇
  1979年   57篇
  1977年   29篇
  1976年   30篇
  1974年   37篇
  1973年   40篇
  1971年   39篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
There are an estimated 56 million orphans and vulnerable children across sub-Saharan Africa. Communities typically care for orphan children through informal caring arrangements – either within or outside of kinship networks. Within Kenya, an estimated 250,000 children live on the streets. There is less research related to fostering attitudes of this special population than orphans and vulnerable children generally. Important research over the past decade has illuminated multiple ways in which children are made more vulnerable because of HIV, including parental death and street-migration from HIV-affected households. As HIV transitions from a terminal illness to a chronic, manageable one, research is also required to establish how parents living with HIV can be an asset to children. In this study, we assess whether mothers living with HIV were very willing to foster biologically-related children, and street-involved children, how these fostering attitudes differed from mothers not living with HIV, and whether differences in fostering attitudes by reported HIV status were mediated by social support, family functioning and general self-rated health. Approximately 40% of mothers living with HIV were very willing to provide long-term foster care to biologically-related or street-involved children. This was less than the percentage of mothers not living with HIV, who were very willing to foster biologically-related children (61%) or street-involved children (58%). Significant portions of these differences were explained by social support, family functioning and general self-rated health. Multi-sectoral approaches are suggested by these findings in order to improve the child-fostering capacity of mothers living with HIV. Improving social support, family functioning and general self-rated health among HIV-infected mothers may not only provide protective benefits for the mothers and their children, but also expand the community’s capacity to care for orphan and vulnerable children.  相似文献   
2.
3.
4.
The concept of participation was reviewed as a component of children's citizenship in order to promote a programme for Integral Development. A narrative revision of the literature was carried out as well as a group discussion was organized along with the staff of an Integral Care Programme, in order to identify notions of democracy and child citizenship related to care and rearing. Some elements that favoured the child participation and some parenting skills were identified. Among the elements that must be encouraged in children are: the development of emotional, cognitive and communicative skills and promotion of decision-making; among the parent skills development included are: sensitivity and responsivity; establishing routines and participation experiences. It is important to stand out that the identified elements to promote child participation and parental competences should be adapted to every specific cultural context.  相似文献   
5.
6.
7.
8.
9.
The effects of nedrocromil sodium and disodium cromoglycate were studied on the anaphylactic contraction of guinea-pig trachea in two models of active sensitization (IgE and IgG models). The influence of epithelial removal on the effects of nedocromil sodium and disodium cromoglycate was examined because several studies have shown that the epithelial layer can modulate agonist- or antigen-induced contractile responses. Disodium cromoglycate (10(-4) M) and nedocromil sodium (10(-4) M) provided significant protection against antigen-induced contractions of guinea-pig tracheal smooth muscle in the IgG model. But only nedocromil sodium had an effect at this concentration in the IgG model and was also effective at 10(-5) M in the epithelium-denuded tracheal strips. At this concentration, disodium cromoglycate lost its protective effect. Comparison with the results obtained with FPL-55712, AA-861 and mepyramine suggested that these drugs affect histamine and particularly leukotriene synthesis and/or release by mast cells or other immunocompetent cells. These findings indicate that nedocromil sodium inhibits the IgE- and IgG-related antigen-induced contraction in guinea-pig airways, whereas disodium cromoglycate inhibits only the IgG-related processes. This study supports the hypothesis that these drugs modulate antigen-induced mediator synthesis and/or release from immunocompetent cells.  相似文献   
10.
Background: Residual neuromuscular blockade remains a problem even after short surgical procedures. The train-of-four (TOF) ratio at the adductor pollicis required to avoid residual paralysis is now considered to be at least 0.9. The incidence of residual paralysis using this new threshold is not known, especially after a single intubating dose of intermediate-duration nondepolarizing relaxant. Therefore, the aim of the study was to determine the incidence of residual paralysis in the postanesthesia care unit after a single intubating dose of twice the ED95 of a nondepolarizing muscle relaxant with an intermediate duration of action.

Methods: Five hundred twenty-six patients were enrolled. They received a single dose of vecuronium, rocuronium, or atracurium to facilitate tracheal intubation and received no more relaxant thereafter. Neuromuscular blockade was not reversed at the end of the procedure. On arrival in the postanesthesia care unit, the TOF ratio was measured at the adductor pollicis, using acceleromyography. Head lift, tongue depressor test, and manual assessment of TOF and DBS fade were also performed. The time delay between the injection of muscle relaxant and quantitative measurement of neuromuscular blockade was calculated from computerized anesthetic records.

Results: The TOF ratios less than 0.7 and 0.9 were observed in 16% and 45% of the patients, respectively. Two hundred thirty-nine patients were tested 2 h or more after the administration of the muscle relaxant. Ten percent of these patients had a TOF ratio less than 0.7, and 37% had a TOF ratio less than 0.9. Clinical tests (head lift and tongue depressor) and manual assessment of fade showed a poor sensitivity (11-14%) to detect residual blockade (TOF < 0.9).  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