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   2150篇
  免费   191篇
  国内免费   10篇
耳鼻咽喉   27篇
儿科学   71篇
妇产科学   53篇
基础医学   282篇
口腔科学   55篇
临床医学   186篇
内科学   456篇
皮肤病学   29篇
神经病学   114篇
特种医学   63篇
外科学   329篇
综合类   53篇
预防医学   97篇
眼科学   165篇
药学   193篇
中国医学   9篇
肿瘤学   169篇
  2024年   7篇
  2023年   33篇
  2022年   86篇
  2021年   135篇
  2020年   61篇
  2019年   90篇
  2018年   106篇
  2017年   79篇
  2016年   85篇
  2015年   91篇
  2014年   127篇
  2013年   115篇
  2012年   173篇
  2011年   175篇
  2010年   91篇
  2009年   65篇
  2008年   84篇
  2007年   88篇
  2006年   71篇
  2005年   70篇
  2004年   69篇
  2003年   59篇
  2002年   44篇
  2001年   35篇
  2000年   39篇
  1999年   36篇
  1998年   17篇
  1997年   12篇
  1996年   10篇
  1995年   10篇
  1994年   10篇
  1993年   11篇
  1992年   29篇
  1991年   15篇
  1990年   17篇
  1989年   21篇
  1988年   16篇
  1987年   13篇
  1986年   9篇
  1985年   7篇
  1984年   5篇
  1983年   4篇
  1982年   6篇
  1981年   6篇
  1980年   3篇
  1975年   3篇
  1973年   3篇
  1972年   2篇
  1971年   2篇
  1964年   1篇
排序方式: 共有2351条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
A multicentre prospective trial was commenced in July 1984 to establish the incidence of otitis media with effusion (OME) in children born with a cleft of the palate. Additionally, the data recorded would allow an assessment of the effect of palatal closure on middle ear function. Prior to palatal closure, 97% of ears in a group of 50 patients had otitis media with effusion (OME). The insertion of a long-term ventilation tube provided a means of aeration of one ear with the non-ventilated ear acting as a control. Eighty percent of control ears had persistent OME during a 24-month follow-up period post palatal repair. It would seem that OME is universally present in children with a cleft palate prior to 4 months of age and this incidence is only marginally diminished by palatal surgery. The liaison between plastic surgical and ENT units should be even closer than before in order to manage these patients satisfactorily.  相似文献   
5.
HK239: a P2 related temperate phage which excludes rII mutants of T4   总被引:7,自引:0,他引:7  
E K Dhillon  T S Dhillon 《Virology》1973,55(1):136-142
  相似文献   
6.
M Ahuja  J Wig  S Grewal  MS Dhillon 《The Knee》1995,2(4):227-231
In a prospective, double blind, randomized study, 30 ASA I patients were allocated to three groups depending on the drug injected intra-articularly, in an attempt to establish the best postoperative analgesic protocol following knee arthroscopy. Group 1 received 3 mg of preservative-free morphine in 25 ml saline; group 2, 5 mg of preservative-free morphine in 25 ml saline; and group 3, 25 ml 0.25% bupivacaine. The degree of postoperative pain was evaluated by visual analogue scale and the need for additional analgesics at 1, 2, 3, 8 and 24 h. We conclude that bupivacaine 0.25% provides analgesia of early onset and of short duration. While 3 mg-preservative free morphine provides moderate postoperative analgesia with peak effect during the eighth postoperative hour, 5 mg preservative-free morphine provides effective and long lasting (more than 24 h) pain relief. No side effects were noted.  相似文献   
7.
The appearance of subepithelial neurosecretory cells (SNC) was investigated by studying completely sampled appendices of 50 children, adolescents and adults. The cells were demonstrated using lead hematoxylin, a selective stain for neurosecretory cells. Additional routinely sampled specimens were also studied for comparison. In children up to the age of 9 yrs only occasional SNC were found. After this age, however, SNC were present in most appendices and in greater numbers. The majority of SNC were located in the distal portion of the appendix, with only small numbers of these cells being present in the proximal segment. Occasional SNC-like cells were identified in the appendiceal submucosa in all regions of the appendix at all ages. This lends support to the hypothesis that a correlation exists between the presence of increased numbers of SNC, patient age and the site distribution of both acute appendicitis and appendiceal carcinoid tumors.  相似文献   
8.
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies.  相似文献   
9.
10.
New pharmaceutical technologies, new drugs, new formulations of existing drugs and changing patterns of consumption are contributing to rising pressure on pharmaceutical budgets. But even as the NHS drugs bill hits a new high, politicians are giving notice that action must be taken to control costs. Managers will be able to do so only if they understand the implications.  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