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   662篇
  免费   33篇
  国内免费   2篇
耳鼻咽喉   14篇
儿科学   17篇
妇产科学   11篇
基础医学   100篇
口腔科学   20篇
临床医学   73篇
内科学   133篇
皮肤病学   10篇
神经病学   54篇
特种医学   7篇
外科学   32篇
预防医学   55篇
眼科学   53篇
药学   44篇
中国医学   3篇
肿瘤学   71篇
  2024年   1篇
  2023年   24篇
  2022年   10篇
  2021年   48篇
  2020年   31篇
  2019年   29篇
  2018年   27篇
  2017年   21篇
  2016年   22篇
  2015年   13篇
  2014年   31篇
  2013年   32篇
  2012年   58篇
  2011年   56篇
  2010年   33篇
  2009年   30篇
  2008年   42篇
  2007年   30篇
  2006年   37篇
  2005年   38篇
  2004年   24篇
  2003年   14篇
  2002年   16篇
  2001年   1篇
  1999年   4篇
  1998年   4篇
  1997年   2篇
  1996年   2篇
  1995年   4篇
  1994年   3篇
  1993年   2篇
  1989年   1篇
  1982年   2篇
  1978年   2篇
  1975年   1篇
  1973年   1篇
  1971年   1篇
排序方式: 共有697条查询结果,搜索用时 281 毫秒
1.
2.
The pediatric intensive care unit at a community hospital successfully implemented the use of standardized concentrations. The process included deciding the standardized concentrations, use of titration charts, and integration of smart pump technology. Since the implementation of standardized concentrations, there has been no signal or sentinel events reported. It is safe and efficacious to use standardized concentrations combined with smart pump technology and abandon the use of the rule of 6 in the pediatric population.  相似文献   
3.
A 33-year-old male presented with acute lymphoblastic leukemia (ALL) characterized by translocation (11;19)(q23;p13.3). He received an allogeneic bone marrow transplant from a matched unrelated donor. Two years later his disease relapsed with an isolated intracardiac mass, presenting as right heart failure. He had no evidence of concomitant relapse in the bone marrow. Tumor cytogenetics revealed clonal evolution with the karyotype 46,XY,t(3;16)(q23;p13),t(11;19)(q23;p13.3), the chromosome 16 breakpoint involving the band where the genes for multidrug resistance-associated protein and CREB binding protein are known to reside. To our knowledge, this is the first report of an isolated extramedullary relapse of ALL in the heart.  相似文献   
4.
Down syndrome regression disorder (DSRD) is a clinical symptom cluster of acute or subacute neurocognitive regression in otherwise health persons with Down syndrome. The objective of this study was to evaluate if adverse childhood experiences (ACEs) were more prevalent in children with DSRD than those with DS alone. A survey-based, cohort-based study was performed. Caregivers of individuals with DSRD with onset of symptoms between age 10 and 30 years and DS alone were administered the ACEs questionnaire via an online REDCap survey. A total of 159 responses were collected after excluding incomplete surveys and those not meeting criteria for DSRD. Individuals with DSRD were not more likely to experience ACEs (p = 0.18, 95% confidence interval [CI]: 0.43–1.17). In those with ACEs prior to the onset of symptoms, the median time prior was 7 months (interquartile range: 5–10). Individuals with DSRD were more likely to report three or more ACEs (52, 33%) compared to those with DS alone (39, 22%) (p = 0.02, 95% CI: 1.08–2.87). Exposure to ACEs were not predictive of response to particular therapeutic interventions although those with multiple ACEs 3 months prior to the onset of symptoms was associated with lower response rates to benzodiazepines and immunotherapy (p = 0.02, 95% CI: −3.64–−1.13). This study provides preliminary data that individuals with DSRD experience ACEs at a similar rate to individuals with only DS alone, although three or more ACEs, often preceding the onset of symptoms, was more prevalent in individuals with DSRD.  相似文献   
5.
A racemic mixture of R and S enantiomers of praziquantel (PZQ) is currently the treatment of choice for schistosomiasis. Though the S enantiomer and the metabolites are presumed to contribute only a little to the activity of the drug, in-depth side-by-side studies are lacking. The aim of this study was to investigate the in vitro activities of PZQ and its main metabolites, namely, R- and S-cis- and R- and S-trans-4′-hydroxypraziquantel, against adult worms and newly transformed schistosomula (NTS). Additionally, we explored the in vivo activity and hepatic shift (i.e., the migration of the worms to the liver) produced by each PZQ enantiomer in mice. Fifty percent inhibitory concentrations of R-PZQ, S-PZQ, and R-trans- and R-cis-4′-hydroxypraziquantel of 0.02, 5.85, 4.08, and 2.42 μg/ml, respectively, for adult S. mansoni were determined in vitro. S-trans- and S-cis-4′-hydroxypraziquantel were not active at 100 μg/ml. These results are consistent with microcalorimetry data and studies with NTS. In vivo, single 400-mg/kg oral doses of R-PZQ and S-PZQ achieved worm burden reductions of 100 and 19%, respectively. Moreover, worms treated in vivo with S-PZQ displayed an only transient hepatic shift and returned to the mesenteric veins within 24 h. Our data confirm that R-PZQ is the main effector molecule, while S-PZQ and the metabolites do not play a significant role in the antischistosomal properties of PZQ.  相似文献   
6.
7.
8.

The chloroform extract of the air-dried leaves of Alternanthera sessilis afforded a mixture of diastereomers of a new ionone derivative 1 whose structures were elucidated by extensive 1D and 2D NMR spectroscopy and mass spectrometry. Oxidative cleavage of 1 to aldehyde 3 with manganese dioxide confirmed diastereoisomerism arose from a racemic side chain chiral centre. Antimicrobial tests on the mixture of diastereomers and the derivative indicated that they have low activities against Pseudomonas aeruginosa and Trichophyton mentagrophytes.  相似文献   
9.
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