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   752篇
  免费   36篇
  国内免费   28篇
儿科学   27篇
妇产科学   10篇
基础医学   74篇
口腔科学   15篇
临床医学   56篇
内科学   136篇
皮肤病学   15篇
神经病学   7篇
特种医学   159篇
外科学   51篇
综合类   122篇
预防医学   27篇
药学   57篇
  1篇
肿瘤学   59篇
  2023年   7篇
  2021年   8篇
  2020年   9篇
  2019年   9篇
  2018年   11篇
  2017年   11篇
  2016年   8篇
  2015年   11篇
  2014年   18篇
  2013年   27篇
  2012年   29篇
  2011年   21篇
  2010年   28篇
  2009年   36篇
  2008年   29篇
  2007年   42篇
  2006年   25篇
  2005年   16篇
  2004年   20篇
  2003年   10篇
  2002年   12篇
  2001年   11篇
  2000年   11篇
  1999年   12篇
  1998年   40篇
  1997年   37篇
  1996年   39篇
  1995年   24篇
  1994年   21篇
  1993年   21篇
  1992年   9篇
  1991年   7篇
  1990年   7篇
  1989年   23篇
  1988年   19篇
  1987年   15篇
  1986年   21篇
  1985年   18篇
  1984年   5篇
  1983年   5篇
  1982年   17篇
  1981年   9篇
  1980年   12篇
  1979年   2篇
  1978年   6篇
  1977年   9篇
  1976年   9篇
  1975年   7篇
  1955年   2篇
  1953年   2篇
排序方式: 共有816条查询结果,搜索用时 6 毫秒
811.
812.
A systematic, large-scale resequencing screen of X-chromosome coding exons in mental retardation
Tarpey et al. (2009)
Nature Genetics 41: 535–543  相似文献   
813.

Background

Nasal modes of respiratory support cause variable amounts of gastric dilatation which may increase gastro-oesophageal reflux (GER) in preterms. To compare the incidence of GER in nasally ventilated, preterm babies with controls (babies not on ventilation). Type of study: A prospective, observational comparative study.

Method

Twenty-three preterm babies of gestational age 28–36 weeks and weight ranging between 1,000 g and < 2,500 g on either nasal continuous positive airway pressure (nCPAP) or nasal intermittent positive pressure venti-lation (nIPPV) were assessed for GER. They were compared with controls not on ventilation some of who were test babies when off ventilation (subgroup A) and some were unrelated babies not on ventilator but matched for gestational age and weight with test babies (subgroup B). All babies were subjected to continuous, oesophageal pH monitoring with dual sensor (upper and lower oesophageal) catheters. Reflux index (RI) was calculated as the percentage of study time the lower oesophageal pH was < 4. Primary outcome was the RI in the test and controls groups. Secondary outcome was the temporal relation of the reflux with symptoms if any. Numerical data were shown as mean with standard deviation and statistical comparisons were done using the χ2-test, Fischer test, and t-test wherever applicable.

Results

The RI was higher in ventilated babies as compared to the control group, particularly in the subgroup A, where test babies formed their own controls. Grade IV reflux (7 cases) was seen only in the ventilated babies. There was no difference in the incidence of GER in babies on nCPAP as compared with nIPPV. Grade IV reflux could not be reliably predicted by RI alone. No definite temporal relation between episodes of reflux and symptoms could be determined in this study.

Conclusion

There is an increase in GER in preterms on nasal modes of ventilation. A combination of upper (pharyngeal) and lower oesophageal sensors are preferred to a single lower oesophageal sensor when assessing GER by oesophageal pHmetry in neonates.  相似文献   
814.

Background:

Supracondylar fractures associated with ipsilateral forearm fractures, aptly termed as “floating elbow” is a rare injury in children after a fall from height. The various authors have reported their results with conservative treatment of one or both injuries to aggressive emergency operative fixation of both components.

Materials and Methods:

During a period of three years, the author managed four cases of floating elbow in children. All cases were managed by closed reduction and pinning of both components of the injury.

Results:

All patients recovered full elbow range of motion at three months followup and were rated as excellent as per modified Flynn''s criteria. None of the patients developed cubitus varus deformity, complications related to the pins or delayed union.

Conclusions:

Early closed reduction and K wire fixation of both components of this injury gives better stability and prevents development of complications like compartment syndrome and elbow deformities.  相似文献   
815.
The current study focussed on documenting the ethnobotanical knowledge of herbal medicines used by the Bapedi traditional healers to treat reproductive ailments in the Limpopo Province, South Africa. Fifty one healers from 17 municipalities covering Capricorn, Sekhukhune and Waterberg districts of the Limpopo Province were interviewed between January and July 2011. Semi-structured interviews, observations and guided field surveys with the healers were employed. Thirty-six medicinal plant species belonging to 35 genera and 20 families were documented. The most used species were Zanthoxylum humile (25.5%), Catha edulis (21.6%), Ozoroa sphaerocarpa (15.7%), Hypoxis hemerocallidea (13.7%), Hypoxis obtusa (11.7%), Gomphocarpus fruticosus subsp. fruticosus and Gymnosporia senegalensis (9.8% each). The dominant growth forms among the reported medicinal plants were herbs (39%), followed by shrubs and trees with 33% and 28%, respectively. The preferred plant parts were roots (63.9%), followed by bark (13.9%), whole plant (11.1%), tubers (8.3%), bulbs (5.6%), fruits, leaves, stems and twigs (2.8% each). The majority of the species were used to treat gender specific reproductive ailments; while a minority were used for treating reproductive ailments of both genders. Twenty-two species (61.1%) are supported by reports of similar uses in other countries or have proven biological activity. This study illustrates that Bapedi traditional healers possess remarkable knowledge on medicinal plants used for treating and managing reproductive ailments.  相似文献   
816.
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