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   2981篇
  免费   159篇
  国内免费   8篇
耳鼻咽喉   45篇
儿科学   373篇
妇产科学   106篇
基础医学   431篇
口腔科学   73篇
临床医学   138篇
内科学   591篇
皮肤病学   89篇
神经病学   67篇
特种医学   71篇
外科学   388篇
综合类   109篇
一般理论   1篇
预防医学   154篇
眼科学   117篇
药学   230篇
中国医学   14篇
肿瘤学   151篇
  2021年   67篇
  2020年   48篇
  2019年   39篇
  2018年   56篇
  2017年   41篇
  2016年   45篇
  2015年   47篇
  2014年   79篇
  2013年   76篇
  2012年   119篇
  2011年   146篇
  2010年   77篇
  2009年   86篇
  2008年   129篇
  2007年   115篇
  2006年   90篇
  2005年   109篇
  2004年   97篇
  2003年   99篇
  2002年   97篇
  2001年   102篇
  2000年   89篇
  1999年   75篇
  1998年   43篇
  1997年   25篇
  1996年   36篇
  1995年   20篇
  1992年   52篇
  1991年   59篇
  1990年   71篇
  1989年   57篇
  1988年   63篇
  1987年   54篇
  1986年   70篇
  1985年   47篇
  1984年   42篇
  1983年   30篇
  1979年   40篇
  1978年   22篇
  1977年   26篇
  1976年   28篇
  1975年   29篇
  1974年   18篇
  1973年   33篇
  1972年   37篇
  1971年   28篇
  1970年   31篇
  1969年   32篇
  1968年   27篇
  1967年   34篇
排序方式: 共有3148条查询结果,搜索用时 140 毫秒
1.
2.
Forty-nine cases of gastroduodenal perforation were subjected to new air insufflation test. The clinical and radiological criteria of air insufflation test were applied to every patient of this study. Forty-seven cases (95.9%) were positive to the new test whereas 2 negative cases turned out to be old sealing perforation. The new test is highly useful in preoperative detection of site of perforation in perforative peritonitis.  相似文献   
3.
A case of malignant fibrous histiocytoma of the mediastinum presenting with unusual features of fever and leucocytosis is reported. This is the youngest patient reported in the literature who had this tumour in the mediastinum.  相似文献   
4.
5.
Background: Ingestion of coins is a common clinical problem in children. Many of the coins are ferromagnetic and can be retrieved with the help of a magnet. We describe the use of a novel endoscopic accessory for removing ferromagnetic coins. Material and methods: Two magnet discs of 1.5 cm diameter were joined to a 200 cm steel wire of 0.75 mm thickness with a terminal 5 cm spring. A Teflon tube (160 cm, 7 F) was used along with this instrument as a sleeve. The use of this accessory was analyzed prospectively in subjects presenting with a history of coin ingestion. The time taken for removal of coins, complications during the procedure and failure rate was noted. Effect of the magnet on cardiac rhythm was also noted during the procedure. Results: A total of 55 children (mean age 5.1 ± 2.3 years) with coin ingestion presented over a period of 1 year. Forty‐four coins were ferromagnetic. All ferromagnetic coins were removed successfully. Mean time for removal was 68 ± 22 s. No complications were encountered. Conclusion: The novel magnetic instrument is precise, safe and quick for the removal of ferromagnetic coins under direct vision.  相似文献   
6.
7.
In most Special Care Neonatal Units (SCNUs) in India, mothers are excluded from the care of their sick babies for fear of over-crowding and dislocation. We have attempted to study the feasibility of involving mothers in the care of their babies admitted for neonatal septicemia and to analyse whether this changed the sepsis related case fatality rate. The study material consisted of 158 neonates with blood culture positive neonatal septicemia whose mothers were actively involved in their care during their stay in the SCNU of LNJPN Hospital throughout 1987-88. The mothers lived in with their sick neonates and were extremely useful in feeding, cleaning, and monitoring for some important signs and symptoms. There were no epidemics of infection in the nursery during this period. All the babies discharged were receiving breast feeds, and the mothers were confident in taking care of them before discharge. The mortality in this group was 43%. The onset of septicemia was most often in the first week (36%) being 25.9% in second week, 26.6% in the third, and 11.4% in the fourth. Mortality was maximum (64.5%) when the onset of illness was in the first 3 days. Klebsiella and S. aureus were commonly isolated organisms (38.6 and 21.5%, respectively). Gram negative organisms were isolated in 66.5% cases with higher mortality in this group. Nearly 46% of the babies weighed 2 kg or less, with a mortality of 60.2% compared to 28.2% in those more than 2 kg. Only 3 to 5% and 40 to 66.7% of Gram negative and 23 and 70% of Gram positive organisms were sensitive to ampicillin and gentamicin, respectively.  相似文献   
8.
9.
Fibronectin (Fn) concentrations were measured immunoturbidimetrically in plasma of normal subjects and patients with peripheral vascular disease (PVD) before and after venous compression, which caused Fn concentrations to increase in both normal subjects and PVD patients. Basal Fn concentrations and those after 10-min compression were not significantly different in normal subjects and PVD patients. Five minutes after the release of compression, Fn had consistently declined in normal subjects and reverted to baseline values; in contrast, in PVD patients values either increased further or decreased inconsistently. Thus the Fn concentration at 15 min was significantly (P less than 0.001) greater in PVD patients than in normal subjects. Plasma albumin concentrations, measured in parallel to ensure that changes in Fn concentrations were not nonspecific, increased to a greater extent in normal subjects than in PVD patients and reverted to normal after the removal of compression. The Fn/albumin ratio remained unchanged in normal subjects after venous compression, whereas that in PVD patients increased and remained higher, even after decompression. The sustained increase in plasma Fn concentrations and in the Fn/albumin ratio in PVD patients after venous compression may indicate endothelial injury.  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