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   1215篇
  免费   153篇
  国内免费   4篇
耳鼻咽喉   18篇
儿科学   56篇
妇产科学   17篇
基础医学   141篇
口腔科学   46篇
临床医学   100篇
内科学   192篇
皮肤病学   8篇
神经病学   54篇
特种医学   118篇
外科学   142篇
综合类   110篇
预防医学   161篇
眼科学   29篇
药学   69篇
中国医学   1篇
肿瘤学   110篇
  2022年   8篇
  2021年   19篇
  2020年   14篇
  2019年   10篇
  2018年   25篇
  2017年   19篇
  2016年   24篇
  2015年   31篇
  2014年   21篇
  2013年   38篇
  2012年   47篇
  2011年   50篇
  2010年   40篇
  2009年   34篇
  2008年   42篇
  2007年   35篇
  2006年   40篇
  2005年   40篇
  2004年   28篇
  2003年   28篇
  2002年   32篇
  2001年   31篇
  2000年   32篇
  1999年   35篇
  1998年   33篇
  1997年   29篇
  1996年   23篇
  1995年   22篇
  1994年   22篇
  1993年   21篇
  1992年   32篇
  1991年   22篇
  1990年   26篇
  1989年   43篇
  1988年   29篇
  1987年   44篇
  1986年   41篇
  1985年   33篇
  1984年   18篇
  1983年   27篇
  1982年   12篇
  1981年   11篇
  1980年   14篇
  1979年   8篇
  1978年   11篇
  1976年   9篇
  1975年   22篇
  1973年   11篇
  1971年   10篇
  1969年   10篇
排序方式: 共有1372条查询结果,搜索用时 10 毫秒
81.
Epistaxis which is not controlled by anterior and posterior nasal packing is usually treated by ligation or embolization of the arterial supply to the nose. Transantral ligation of the maxillary artery, or embolization of its branches, have recently been considered the treatments of choice. Ligation of the external carotid artery has the advantage of being a short procedure which can be readily performed under local anesthesia, and does not require particular surgical expertise or the use of specialized equipment. This procedure, in combination with ligation of the ipsilateral anterior ethmoidal artery, controlled the bleeding in 14 of 15 patients over a nine-year period. There were no deaths and no significant complications. Although ligation and embolization of the maxillary artery are of proven efficacy, ligation of the external carotid artery is similarly effective and its simplicity may still make it the procedure of choice in some situations.  相似文献   
82.
Objectives : To determine the efficacy of antimicrobial treatment in non-dysenteric persistent diarrhoea in a community setting. Methods : In this double-blind field trial, 156 children aged 4 36 months with persistent diarrhoea not associated with Giardia lamblia infestation seeking treatment in a community outpatient clinic, were randomized to receive a combination of nalidixic acid and metronidazole, metronidazole alone, or placebo for 7 days. Results : In comparison with placebo, metronidazole treatment did not result in a significant reduction in the mean post-enrolment diarrhoeal duration and stool frequency, increase in the proportion of patients recovered by days 3, 5 and 7 of treatment, and increase in weight gain at days 7 and 14. Comparing the combination of nalidixic acid and metronidazole with metronidazole alone, 17.5% more children treated with the combination recovered by day 3 of treatment ( p = 0.08) and the mean stool frequency ascertained on day 7 for the previous 24 h was 26.8% less in them ( p = 0.05). The weight gains at days 7 and 14 were similar in the two groups. Conclusions : These findings indicate that metronidazole offers no therapeutic benefit in persistent diarrhoea not associated with Giardia lamblia and nalidixic acid has only a modest clinical benefit, which is not substantial enough to warrant its routine use.  相似文献   
83.
84.
85.
86.
87.

Background

Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.

Methods

Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.

Results

The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3rd post-operative day showing lack of activation of platelets in cases of severe bleeding.

Conclusion

Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage  相似文献   
88.
89.
The effect of otitis media with effusions on balance in children   总被引:1,自引:0,他引:1  
There is increasing interest in the effect, otitis media with effusions (OME) has on the balance in children. The aim of our investigation was to determine whether a universal effect on balance could be demonstrated in children with OME by using sway posturography. Assessment was made in 20 children with proven OME before and after the insertion of bilateral ventilation tubes. Sway posturography was performed on each occasion in each of the four recording conditions in the presence and absence of both reduced optic fixation and reduced proprioception. The pathlength traversed during the recording interval was measured and analysed by a split-unit anova. The results demonstrate an overall improvement in mean pathlength of 20% following treatment of the effusions (P < 0.001) (95% CI 14-25%). The effect of reduced optic fixation and of reduced proprioception were similar when increasing the mean pathlength by 22% (P < 0.001). These results demonstrate that OME has a universal effect on balance in all recording conditions.  相似文献   
90.
The mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome is a rare congenital disorder of mitochondrial DNA (mt-DNA). Patients with this syndrome may present to the otolaryngologist with sensorineural hearing loss (SNHL), which is genetic in origin. A high index of suspicion is required because this hearing loss is part of a syndrome for which early diagnosis and intervention is required.  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