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   853篇
  免费   17篇
  国内免费   1篇
耳鼻咽喉   13篇
儿科学   26篇
妇产科学   11篇
基础医学   140篇
口腔科学   11篇
临床医学   106篇
内科学   75篇
皮肤病学   34篇
神经病学   16篇
特种医学   107篇
外科学   128篇
综合类   9篇
预防医学   115篇
眼科学   15篇
药学   28篇
中国医学   2篇
肿瘤学   35篇
  2016年   7篇
  2015年   5篇
  2014年   7篇
  2013年   21篇
  2012年   13篇
  2011年   11篇
  2010年   23篇
  2009年   20篇
  2008年   8篇
  2007年   19篇
  2006年   23篇
  2005年   15篇
  2004年   8篇
  2003年   25篇
  2002年   24篇
  2001年   17篇
  2000年   18篇
  1999年   17篇
  1998年   17篇
  1997年   13篇
  1996年   14篇
  1995年   11篇
  1994年   8篇
  1993年   8篇
  1992年   15篇
  1991年   36篇
  1990年   35篇
  1989年   35篇
  1988年   37篇
  1987年   40篇
  1986年   32篇
  1985年   43篇
  1984年   20篇
  1983年   20篇
  1982年   6篇
  1981年   11篇
  1980年   12篇
  1979年   16篇
  1978年   13篇
  1977年   11篇
  1976年   18篇
  1975年   22篇
  1974年   12篇
  1973年   11篇
  1972年   6篇
  1971年   14篇
  1970年   6篇
  1969年   6篇
  1968年   5篇
  1966年   5篇
排序方式: 共有871条查询结果,搜索用时 0 毫秒
41.
Vesicular bodies are observed during enzymatic degradation of the yeast cell wall and in the course of wall regeneration. In both cases various types of vesicles are formed and exocytated by different mechanisms. They are characterized cytochemically and their possible role in cell wall regeneration is discussed.  相似文献   
42.
43.
44.
Jahng TA  Fu TS  Cunningham BW  Dmitriev AE  Kim DH 《Neurosurgery》2004,54(1):171-80; discussion 180-1
OBJECTIVE: The goal of this study was to use a minimally invasive endoscopic surgical technique in a sheep model to evaluate the efficacy of an osteoinductive growth factor, recombinant human growth/differentiation factor-5 (also designated MP52), and an osteoconductive matrix formulation (Healos; DePuy AcroMed, Inc., Mountain View, CA) for inducing and facilitating bone formation. METHODS: Twelve mature sheep underwent bilateral posterolateral lumbar fusion and pedicle screw fixation via a posterior endoscopic approach. Each sheep received two different types of graft material, autogenous iliac crest bone, or a bone graft substitute (MP52 with Healos), inserted into the right and left sides of the spine in an alternating fashion. Groups of four sheep were killed at 2, 4, and 6 months postoperatively for manual, radiographic, and histological evaluation. RESULTS: No neurological impairments, infections, or other complications were observed. After 2 months, partial fusion on both sides was observed, but radiographic evaluation showed greater bone growth on the side that received the bone graft substitute. Solid posterolateral fusion was observed in both autograft and bone graft substitute sites at 4 and 6 months, and autograft and Healos MP52 fusion sites were essentially the same at histological examination. There was no abnormal overgrowth of new bone from either of these two materials. CONCLUSION: Endoscopic posterolateral lumbar arthrodesis and instrumentation is feasible, safe, and effective in a sheep model. Healos is a useful bonding agent that mimics natural bone in posterolateral intertransverse fusion sites. Combined with MP52, it produced fusion comparable to that of autogenous bone graft. Minimally invasive techniques and bone graft substitutes could eliminate morbidity and increase the likelihood of successful fusion.  相似文献   
45.
Medical histories of 214 patients hospitalized with diagnosis "recurrent nodular goiter" were studied retrospectively. Complex clinical, laboratory and instrumental examination was carried out in all the patients. Comparative analysis demonstrated that in the structure of recurrent goiter nodular colloid form dominated (84.1%), only in 42.1% cases repeated surgeries were indicated. Other patients (15.9%) were the ones underwent surgery for other thyroid diseases (hypertrophied form of autoimmune thyroiditis, follicular adenoma, thyroid cysts, thyroid cancer). Inadequate surgery and prophylactic therapy with iodine drugs were the main causes of recurrent goiter. Adequate iodine prophylaxis (potassium iodide 100-200 mg per day), complex examination of patients, correct indications for primary surgery and adequate surgical volume, valuable postoperative therapy (iodine drug, LT-4 if it is necessary) permit to reduce the risk of recurrent nodular (multiple-nodular, diffuse-nodular) goiter. Ways of researches for improvement of diagnosis, prophylaxis and treatment results of "recurrence nodular goiter" are projected.  相似文献   
46.
Tympanic and axillary temperatures were measured in 90 children (161 ears) with exudative otitis media (EOM) and 20 otologically healthy children (40 ears). It was discovered that in EOM patients the difference between tympanic and axillary temperatures is greater than in healthy children. This increased difference is caused by the state of the tympanic mucosa. The influence of surgical and conservative treatments on tympanic mucosa temperature and, therefore, on the difference between tympanic and axillary temperatures in these patients are outlined. It is recommended to use tympanic thermometry with consideration of case history data and otoscopic picture as a screening method for diagnosis of EOM in mass prevention examinations of children, in family physician practice and in selection of children for more comprehensive check-up in diagnostic centers as well as for control over treatment results in EOM children.  相似文献   
47.
48.
基于物体空间序法的CT图像三维重建算法的研究   总被引:5,自引:0,他引:5  
首先对三维可视化方法进行了分类概述。接着对基本的物体空间序法及其改进算法——抛雪球法做了详细的描述,并且通过对两组CT数据进行三维重建实验,得到高质量的重构图像。最后,本文研究并采用了提取表面体素进行体绘制加速的方法,实现了基于等值面提取表面的加速算法,实验证明加速算法能够满足显示要求并能起到明显的加速作用。  相似文献   
49.
50.
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