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   507篇
  免费   34篇
  国内免费   1篇
耳鼻咽喉   1篇
儿科学   11篇
妇产科学   5篇
基础医学   62篇
口腔科学   11篇
临床医学   35篇
内科学   95篇
皮肤病学   1篇
神经病学   21篇
特种医学   84篇
外科学   86篇
综合类   18篇
预防医学   29篇
眼科学   13篇
药学   22篇
中国医学   3篇
肿瘤学   45篇
  2022年   6篇
  2021年   4篇
  2020年   9篇
  2019年   10篇
  2018年   14篇
  2017年   16篇
  2016年   15篇
  2015年   15篇
  2014年   23篇
  2013年   26篇
  2012年   34篇
  2011年   30篇
  2010年   14篇
  2009年   25篇
  2008年   16篇
  2007年   17篇
  2006年   34篇
  2005年   21篇
  2004年   17篇
  2003年   12篇
  2002年   15篇
  2001年   14篇
  2000年   9篇
  1999年   13篇
  1998年   5篇
  1997年   7篇
  1995年   8篇
  1994年   8篇
  1993年   3篇
  1992年   5篇
  1991年   9篇
  1990年   3篇
  1989年   7篇
  1988年   5篇
  1986年   3篇
  1985年   5篇
  1984年   3篇
  1980年   7篇
  1979年   6篇
  1978年   5篇
  1977年   3篇
  1974年   3篇
  1967年   2篇
  1966年   3篇
  1954年   2篇
  1949年   2篇
  1948年   4篇
  1946年   2篇
  1945年   2篇
  1944年   2篇
排序方式: 共有542条查询结果,搜索用时 15 毫秒
51.
This study examined motor behaviors in a longitudinal cohort of infant siblings of children with autism. Stereotypic movements and postures occurring during standardized observational assessments at 12 and 18 months were coded from videotapes. Participants included eight infant siblings later diagnosed with autism spectrum disorder (ASD), a random sample of nine non-diagnosed siblings, and 15 controls. Videos were coded blind to diagnostic group. At 12 and 18 months the ASD group “arm waved” more frequently and at 18 months, one posture (“hands to ears”) was more frequently observed in the ASD and non-diagnosed group compared to the controls. Overall, the siblings subsequently diagnosed with ASD and the comparison groups had considerable overlap in their repertoires of stereotyped behaviors.  相似文献   
52.
PVS-RIPO is a recombinant oncolytic poliovirus designed for clinical application to target CD155 expressing malignant gliomas and other malignant diseases. PVS-RIPO does not replicate in healthy neurons and is therefore non-pathogenic in rodent and non-human primate models of poliomyelitis. A tetrazolium salt dye-based cellular assay was developed and qualified to define the cytotoxicity of virus preparations on susceptible cells and to explore the target cell specificity of PVS-RIPO. In this assay, PVS-RIPO inhibited proliferation of U87-MG astrocytoma cells in a dose-dependent manner. However, HEK293 cells were much less susceptible to cell killing by PVS-RIPO. In contrast, the Sabin type 1 live attenuated poliovirus vaccine strain (PV(1)S) was cytotoxic to both HEK293 and U87-MG cells. The correlation between expression of CD155 and cytotoxicity was also explored using six different cell lines. There was little or no expression of CD155 and PVS-RIPO-induced cytotoxicity in Jurkat and Daudi cells. HEK293 was the only cell line tested that showed CD155 expression and resistance to PVS-RIPO cytotoxicity. The results indicate that differential cytotoxicity measured by the colorimetric assay can be used to evaluate the cytotoxicity and cell-type specificity of recombinant strains of poliovirus and to demonstrate lot to lot consistency during the manufacture of viruses intended for clinical use.  相似文献   
53.
54.
The Deficit Reduction Act of 2005 makes changes in the Medicaid program that may have a significant effect on children's health. Nurses and other health care professionals should be aware of these changes in order to monitor the impact of the legislation, guide families in the process of accessing needed services, and advocating on behalf of children and families.  相似文献   
55.
56.
Since its identification as a unique species in 1982, Escherichia hermannii has only recently been implicated as a pathogenic organism in human diseases. Literature search indicates removal of hemodialysis catheter as being essential to the success of treatment for bacteremia with this organism. However, having no alternative access for hemodialysis led to the attempt to salvage the catheter with the use of Antibiotic lock therapy. This case highlights Antibiotic lock therapy as an indication in Escherichia hermanii Catheter related Bloodstream infection.  相似文献   
57.
58.
59.
To investigate the role of glucagon and insulin receptor binding in the glucagon hypersensitivity and insulin resistance which characterize the glucose intolerance of uremia, liver plasma membranes were prepared from control rats (blood urea nitrogen [BUN] 15+/-1 mg/100 ml, creatinine 0.7+/-0.2 mg/100 ml), and from 70% nephrectomized rats (BUN 30+/-2 mg/100 ml, creatinine 2.2+/-0.2 mg/100 ml), and from 90% nephrectomized rats (BUN 46+/-3 mg/100 ml, creatinine 4.20+/-0.7 mg/100 ml), 4 wk after surgery. As compared to controls, the 90% nephrectomized rats had significantly higher levels of plasma glucose (95+/-4 vs. 125+/-11 mg/100 ml), plasma insulin (28+/-9 vs. 52+/-11 muU/ml), and plasma glucagon (28+/-5 vs. 215+/-18 pg/ml). Similar, but less marked, elevations were observed in the 70% nephrectomized animals.In liver plasma membranes from nephrectomized rats, specific binding of (125)I-glucagon was increased by 80-120%. Furthermore, glucagon (2 muM)-stimulated adenylate cyclase activity in nephrectomized rats was twofold higher than in controls. In contrast, fluoridestimulated adenylate cyclase activity was similar in both groups of rats. In marked contrast to glucagon binding, specific binding of (125)I-insulin to liver membranes from nephrectomized rats was reduced by 40-50% as compared to controls. Data analysis suggested that the changes in both glucagon and insulin binding are a consequence of alterations in binding capacity rather than changes in affinity. Liver plasma membranes from nephrectomized rats degraded (125)I-glucagon and (125)I-insulin to the same extent as control rats.THESE RESULTS DEMONSTRATE THAT: (a) the 70 and 90% nephrectomized rats simulate the hyperglycemia, hyperinsulinemia, and hyperglucagonemia observed in clinical uremia; (b) in these animals specific binding of glucagon to liver membranes is increased and is accompanied by higher glucagon-stimulated adenylate cyclase activity; and (c) specific binding of insulin is markedly decreased. These findings thus provide evidence of oppositely directed, simultaneous changes in glucagon and insulin receptor binding in partially nephrectomized rats. Such changes may account for the hypersensitivity to glucagon and may contribute to resistance to insulin observed in the glucose intolerance of uremia.  相似文献   
60.
A 25-year-old man in New York Heart Association functional class IV with right ventricular endomyocardial fibrosis received a palliative bidirectional Glenn shunt. Despite a stormy postoperative convalescence the bidirectional Glenn shunt provided good long-term palliation.  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