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   3162598篇
  免费   228153篇
  国内免费   4917篇
耳鼻咽喉   44880篇
儿科学   103931篇
妇产科学   88112篇
基础医学   463363篇
口腔科学   88284篇
临床医学   282269篇
内科学   607561篇
皮肤病学   69137篇
神经病学   249619篇
特种医学   120038篇
外国民族医学   818篇
外科学   479020篇
综合类   66887篇
现状与发展   12篇
一般理论   1076篇
预防医学   245436篇
眼科学   74438篇
药学   237212篇
  12篇
中国医学   6172篇
肿瘤学   167391篇
  2018年   34131篇
  2017年   25639篇
  2016年   28823篇
  2015年   32691篇
  2014年   45881篇
  2013年   69314篇
  2012年   95504篇
  2011年   101810篇
  2010年   60505篇
  2009年   57037篇
  2008年   96336篇
  2007年   102942篇
  2006年   104096篇
  2005年   101268篇
  2004年   97155篇
  2003年   93700篇
  2002年   91195篇
  2001年   140719篇
  2000年   144345篇
  1999年   121730篇
  1998年   35888篇
  1997年   31578篇
  1996年   31943篇
  1995年   30075篇
  1994年   27900篇
  1993年   26222篇
  1992年   95986篇
  1991年   93880篇
  1990年   92029篇
  1989年   89030篇
  1988年   82273篇
  1987年   80765篇
  1986年   76396篇
  1985年   73237篇
  1984年   54698篇
  1983年   46838篇
  1982年   28168篇
  1981年   25207篇
  1979年   51168篇
  1978年   36392篇
  1977年   30765篇
  1976年   29303篇
  1975年   31922篇
  1974年   37929篇
  1973年   36354篇
  1972年   34338篇
  1971年   32379篇
  1970年   29970篇
  1969年   28666篇
  1968年   26645篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A new rapid procedure for desiccating frozen resin-cracked retinal tissue for scanning electron microscopy (SEM) which permits air-drying was found to compare favorably with tissues prepared by critical-point drying: Retinal tissue was fixed in 4% phosphate-buffered neutral formaldehyde, dehydrated by means of graded ethanol, embedded in Epon, cracked and washed in propylene oxide. For desiccation, the specimens were immersed in hexamethyldisilazane (HMDS), air-dried and finally sputter-coated. The method is time-saving, gives extended information in SEM, and the number of good specimens is increased.  相似文献   
992.
993.
Case-adjusted prospective reimbursement systems, such as resource utilization groups (RUGs), may promote nursing home cost containment, but they may do no better than existing systems at encouraging homes to admit the more dependent and thus costlier Medicaid patients, if the homes' reluctance to admit these patients is due to a shortage of nursing home beds. Using 1983 data on Wisconsin nursing homes, this paper presents evidence that suggests that the presence of excess demand, rather than low reimbursement rates, causes nursing homes to exclude the more costly Medicaid patients. Consequently, to benefit fully from RUGs, it is necessary either to eliminate excess demand (by increasing supply or decreasing demand) or to decide which patients have priority for admission and assign reimbursement payments to these patients that significantly favor these patients. Otherwise, access to nursing home care under RUGs is left to chance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation.  相似文献   
995.
996.
Sex hormone implants have been available for almost 50 years, but only a few clinicians administer them regularly. Implants represent a physiologic mode of therapy with many metabolic advantages over other routes. Surprisingly, they are relatively ignored by physicians. This may well reflect their surgical nature, although the technique of hormone implantation is simple and fast and obviates daily oral medication. As the list of indications for hormone pellets grows, more patients will take advantage of the benefits they offer.  相似文献   
997.
998.
999.
1000.
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