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   1442篇
  免费   83篇
  国内免费   4篇
耳鼻咽喉   8篇
儿科学   79篇
妇产科学   35篇
基础医学   179篇
口腔科学   45篇
临床医学   108篇
内科学   338篇
皮肤病学   24篇
神经病学   34篇
特种医学   420篇
外科学   92篇
综合类   40篇
预防医学   43篇
眼科学   11篇
药学   41篇
  1篇
肿瘤学   31篇
  2023年   4篇
  2022年   3篇
  2021年   8篇
  2020年   7篇
  2019年   9篇
  2018年   11篇
  2017年   18篇
  2016年   11篇
  2015年   14篇
  2014年   32篇
  2013年   35篇
  2012年   21篇
  2011年   31篇
  2010年   38篇
  2009年   60篇
  2008年   31篇
  2007年   48篇
  2006年   40篇
  2005年   36篇
  2004年   22篇
  2003年   18篇
  2002年   12篇
  2001年   19篇
  2000年   14篇
  1999年   20篇
  1998年   81篇
  1997年   80篇
  1996年   81篇
  1995年   64篇
  1994年   39篇
  1993年   58篇
  1992年   6篇
  1991年   11篇
  1990年   25篇
  1989年   53篇
  1988年   42篇
  1987年   48篇
  1986年   53篇
  1985年   69篇
  1984年   36篇
  1983年   31篇
  1982年   30篇
  1981年   31篇
  1980年   37篇
  1979年   5篇
  1978年   18篇
  1977年   23篇
  1976年   21篇
  1975年   20篇
  1914年   1篇
排序方式: 共有1529条查询结果,搜索用时 0 毫秒
11.
12.
RA Kumar 《Clinical genetics》2008,74(4):343-344
De novo mutations in the gene encoding STXBP1 (MUNC18‐1) cause early infantile epileptic encephalopathy
Saitsu et al. (2008)
Nature Genetics 40: 782–788  相似文献   
13.
14.
15.
16.
Tay-Sachs and Sandhoff diseases are autosomal recessive neurodegenerative diseases resulting from the inability to catabolize GM2 ganglioside by beta-hexosaminidase A (Hex A) due to mutations of the alpha subunit (Tay-Sachs disease) or beta subunit (Sandhoff disease) of Hex A. Hex B (beta beta homodimer) is also defective in Sandhoff disease. We previously developed mouse models of both diseases and showed that Hexa-/- (Tay-Sachs) mice remain asymptomatic to at least 1 year of age while Hexb-/- (Sandhoff) mice succumb to a profound neurodegenerative disease by 4-6 months of age. Here we find that neuron death in Hexb-/- mice is associated with apoptosis occurring throughout the CNS, while Hexa-/- mice were minimally involved at the same age. Studies of autopsy samples of brain and spinal cord from human Tay-Sachs and Sandhoff diseases revealed apoptosis in both instances, in keeping with the severe expression of both diseases. We suggest that neuron death is caused by unscheduled apoptosis, implicating accumulated GM2 ganglioside or a derivative in triggering of the apoptotic cascade.   相似文献   
17.
The antenatal variant of Bartter's syndrome is an autosomal recessive kidney disease characterized by polyhydramnios, premature delivery, hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous, having been linked recently to mutations in an ATP- sensitive, renal outer medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl co-transporter, NKCC2. We characterized four of the mutations reported in three heterozygous ROMK variants of antenatal Bartter's and found that each expressed a distinct phenotype in Sf9 cells. One mutation expressed normal function and appears to be an allelic polymorphism. The other three mutations produced channels with significantly reduced K+fluxes. However, the mechanisms in each case were different and reflected abnormalities in phosphorylation, proteolytic processing or protein trafficking. The different mechanisms may be important in the design of appropriate therapy for patients with this disease.   相似文献   
18.
19.
The influence of reported paternal attitudes on the decision to breast-feed   总被引:1,自引:0,他引:1  
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions.  相似文献   
20.
OBJECTIVE: Most neonatologists include an apnea-free period in the criteria for the discharge of preterm infants. However, the length of time one should wait after the cessation of apnea before sending an infant home without a monitor is debated. We undertook this study in an attempt to define a minimal and safe observation period between the time of the last apnea episode and discharge. METHODS: We reasoned that in infants with idiopathic apnea of prematurity, the intervals between days on which apnea occurs gradually increase until some point at which clinically significant apnea ceases. Therefore, knowledge about the intervals between days on which apnea occurred just before the last apnea would provide a reasonable estimate of the minimal safe observation interval between the last apnea and discharge. We reviewed the charts of 266 infants born in 1993 and 1994 at 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