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   3507篇
  免费   240篇
  国内免费   4篇
耳鼻咽喉   47篇
儿科学   127篇
妇产科学   44篇
基础医学   363篇
口腔科学   313篇
临床医学   200篇
内科学   1086篇
皮肤病学   93篇
神经病学   160篇
特种医学   54篇
外科学   530篇
综合类   14篇
一般理论   1篇
预防医学   222篇
眼科学   64篇
药学   208篇
中国医学   8篇
肿瘤学   217篇
  2023年   17篇
  2022年   29篇
  2021年   105篇
  2020年   49篇
  2019年   100篇
  2018年   112篇
  2017年   77篇
  2016年   65篇
  2015年   78篇
  2014年   100篇
  2013年   132篇
  2012年   168篇
  2011年   226篇
  2010年   129篇
  2009年   137篇
  2008年   149篇
  2007年   193篇
  2006年   162篇
  2005年   177篇
  2004年   180篇
  2003年   169篇
  2002年   166篇
  2001年   140篇
  2000年   176篇
  1999年   118篇
  1998年   49篇
  1997年   43篇
  1996年   30篇
  1995年   15篇
  1994年   19篇
  1993年   11篇
  1992年   64篇
  1991年   56篇
  1990年   56篇
  1989年   50篇
  1988年   38篇
  1987年   26篇
  1986年   23篇
  1985年   21篇
  1984年   5篇
  1983年   10篇
  1979年   6篇
  1978年   8篇
  1975年   8篇
  1973年   4篇
  1972年   4篇
  1971年   4篇
  1970年   7篇
  1968年   7篇
  1966年   4篇
排序方式: 共有3751条查询结果,搜索用时 15 毫秒
1.
The current situation in which the humanities are disparaged affects all university disciplines, including nursing, in whose historical evolution the humanities have always been present in one form or another. Looking beyond this disrepute, this study proposes that nursing renew its attention to classical philosophy. Specifically, it invites a close reading of Xenophon's Anabasis and Plato's Meno, to get three related goals: to show how the use of ancient texts are very valuable tools for the philosophical initiation of nursing students and can help them reflect on their choice of nursing as a practical activity; to reflect on the problem of virtue and the nature of the good life; and to show how the interaction with ancient texts allows students to reflect on questions and issues of life, theirs and others, that are not open to investigation through a purely scientific method. Consequently, both Anabasis and Meno readings strengthen the intellectual relationship between philosophy and nursing, enabling the latter to delve deeper into the key questions of its own thought as a discipline.  相似文献   
2.
To evaluate the changes in alveolar contour after guided bone regeneration (GBR) with two different combinations of biomaterials in dehiscence defects arou  相似文献   
3.
4.
5.
6.
7.
8.
Introduction and objectiveWhen sleep apnea-hypopnea syndrome (SAHS) and cardiovascular disease occur concurrently, prognosis is affected. Echocardiography can detect structural cardiac abnormalities but using this technique in all patients would place a heavy burden on resources. The objective of this study was to investigate whether the N-terminal fraction of brain natriuretic peptide (NT-proBNP) can be used as a marker for silent heart disease.Patients and methodsNT-proBNP concentration was measured in the 114 consecutive patients with SAHS who underwent echocardiography before starting treatment. Left and right ventricular systolic and diastolic function, as well as structural abnormalities, were studied. Correlations between NT-proBNP concentration and the abnormalities detected were investigated. A receiver operating characteristics (ROC) curve was plotted for NT-proBNP concentration and cardiac abnormalities.ResultsData for 98 patients were finally analyzed. NT-proBNP concentration was significantly correlated with ventricular septal thickness (r=0.63), posterior wall thickness (r=0.45), and left ventricular enddiastolic diameter (r=0.51) (P<.0001 for all correlations). The area under the ROC curve was significant (0.870; 95% confidence interval, 0.801-0.939; P<.0001). Assuming that specificity would be more useful for clinical practice, we calculated that NT-proBNP concentrations below 100 and 200 pg/mL could rule out structural abnormalities with a reliability of 90% and 100%, respectively.ConclusionsNT-proBNP concentration was strongly correlated with echocardiographic abnormalities and so could be a useful tool for identifying patients who should be referred to the cardiologist.  相似文献   
9.
R 75251, a new inhibitor of steroid biosynthesis   总被引:1,自引:0,他引:1  
R 75251, a new imidazole derivative, inhibited the conversion of androgens to estrogens, of progestins to androstenedione and testosterone, and of 11-deoxycorticosterone to corticosterone in human placenta microsomes, subcellular fraction of rat testis, bovine adrenocortical mitochondria, in cultured rat granulosa, testicular and adrenal cells, respectively. In vitro, no effect on cholesterol synthesis and cholesterol side-chain cleavage was found at concentrations up to 10 microM. In rat granulosa cells, no effect on progesterone production was detected. In vitro, no effect on steroid radioligand binding was observed. In male volunteers, a single dose of 300 mg of R 75251 significantly lowered plasma testosterone and estradiol for 24 hours and increased plasma concentration of 17 alpha-hydroxyprogesterone and progesterone. As compared with ketoconazole high dose (600 mg b.i.d), R 75251 (300 mg b.i.d) was at least as efficacious as inhibitor of testosterone synthesis when studied during ACTH stimulation. In contrast to ketoconazole, R 75251 did not significantly affect circulating adrenal androgen levels in male volunteers. Precursors of gluco- and mineralocorticoids such as 11-deoxycortisol and 11-deoxycorticosterone accumulated more than after ketoconazole administration. The data show that the cytochrome P450-dependent aromatase, 17-hydroxylase/17,20-lyase, and 11-hydroxylase are the target enzymes for R 75251.  相似文献   
10.
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