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   4795篇
  免费   169篇
  国内免费   14篇
耳鼻咽喉   57篇
儿科学   308篇
妇产科学   87篇
基础医学   582篇
口腔科学   109篇
临床医学   348篇
内科学   1164篇
皮肤病学   105篇
神经病学   169篇
特种医学   249篇
外科学   642篇
综合类   187篇
一般理论   1篇
预防医学   216篇
眼科学   167篇
药学   300篇
  2篇
中国医学   17篇
肿瘤学   268篇
  2024年   16篇
  2023年   31篇
  2022年   77篇
  2021年   165篇
  2020年   85篇
  2019年   130篇
  2018年   152篇
  2017年   101篇
  2016年   119篇
  2015年   134篇
  2014年   169篇
  2013年   211篇
  2012年   325篇
  2011年   319篇
  2010年   185篇
  2009年   149篇
  2008年   238篇
  2007年   255篇
  2006年   196篇
  2005年   168篇
  2004年   158篇
  2003年   141篇
  2002年   127篇
  2001年   94篇
  2000年   101篇
  1999年   84篇
  1998年   51篇
  1997年   42篇
  1996年   34篇
  1995年   24篇
  1994年   39篇
  1993年   26篇
  1992年   61篇
  1991年   75篇
  1990年   57篇
  1989年   84篇
  1988年   54篇
  1987年   51篇
  1986年   52篇
  1985年   48篇
  1984年   29篇
  1983年   28篇
  1982年   33篇
  1980年   18篇
  1979年   27篇
  1977年   21篇
  1976年   28篇
  1975年   17篇
  1973年   16篇
  1966年   14篇
排序方式: 共有4978条查询结果,搜索用时 0 毫秒
1.
The diagnosis of acute disseminated encephalomyelitis (ADEM) is frequently missed or delayed with consequent delay in instituting therapy in the crucial phase of the illness. The role of MRI in the diagnosis of ADEM is well established, however, the value of its early utilization of treatment on the outcome of patients has not been adequately stressed. Three patients with ADEM are described. Delay in the diagnosis of the first was associated with severe sequelae, while in the other two early diagnosis and institution of corticosteroid therapy which was facilitated by MRI, was associated with a better outcome. MRI should be carried out early once the diagosis of ADEM is entertained.  相似文献   
2.
3.
4.
A case of destructive ocular myiasis resulting in complete loss of the globe in two days time is documented. To the best of our knowledge this is the first report of such a severe involvement in a healthy and non-compromised host. Mechanical removal and good local hygiene helped heal the wound. The larvae were isolated to be that of Chrysomyia bezziana (screwworm fly). This is possibly the first report of destructive ocular myiasis caused by Chrysomyia bezziana from the Indian subcontinent and the second in world literature. Infestation of human eyes with larvae of flies (myiasis) has been reported. Serious consequences of destructive myiasis are seen in emaciated and diseased patients. Only one report of total destruction of the globe by maggots of Chrysomyia bezziana exists in the literature. As in previous communications, the patient in this report had no predisposing factors both systemic and local. We here in document a case of orbital myiasis leading to rapid destruction of the globe within two days in a healthy and a non-compromised patient.  相似文献   
5.
6.
Estimation of T and B lymphocytes was done in 50 patients of enteric fever, 50 duration matched non enteric fever patients and 50 normal healthy individuals. The difference in both early and late rosette forming T lymphocytes was found to be statistically significant in enteric versus non-enteric patients. Significant difference was also observed in enteric versus normal individuals in case of late rosette forming T lymphocytes.  相似文献   
7.
8.
BACKGROUND: Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders. OBJECTIVE: The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract. METHODS: The Ic extract was kept with 0.1 mepsilon-aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 degrees C, 4 degrees C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS-PAGE, Western blot, ELISA, ELISA inhibition and skin test. RESULTS: Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS-PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67-kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract. CONCLUSION: EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage.  相似文献   
9.
In the present study 60 diabetics were examined for intraocular pressure, scleral rigidity and facility of outflow. The intraocular pressure was found higher than in the general population except in patients with proliferative retinopathy. There was no marked difference in scleral rigidity in diabetics. The facility of outflow was lower in diabetic patients.  相似文献   
10.
The long term performance of various pacing leads in use for at least one year is reported from one centre. Between January 1975 and December 1990, 1056 cardiac pacing leads were implanted in 881 patients (mean age 57 +/- 13 years). Eight hundred and three leads were silicone insulated (SI) and 253 leads were polyurethane insulated (PUI). Leads from different manufacturers were used (Medtronic, CPI, Telectronics). The average duration of follow up was 56.6 +/- 77 months (range 12-221 months) for SI and 47.1 +/- 24 months (range 12-99 months) for PUI leads. Overall lead failure occurred more often in the PUI group (n = 46, 18.2%) compared to SI group (n = 93, 11.3%, p < 0.025). Majority of lead failures occurred in the first 36 months after implantation. In particular, Medtronic models 6971, 6972 (urethane) and 6901 (silicone) showed higher rate of complications (25.5%, 26.3% and 44.5% respectively).  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