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   2270602篇
  免费   158967篇
  国内免费   5737篇
耳鼻咽喉   30747篇
儿科学   73178篇
妇产科学   60994篇
基础医学   328901篇
口腔科学   62289篇
临床医学   211831篇
内科学   432392篇
皮肤病学   48747篇
神经病学   181990篇
特种医学   86800篇
外国民族医学   563篇
外科学   326638篇
综合类   47506篇
现状与发展   3篇
一般理论   709篇
预防医学   178293篇
眼科学   51362篇
药学   174437篇
  12篇
中国医学   5942篇
肿瘤学   131972篇
  2021年   18136篇
  2019年   18644篇
  2018年   26272篇
  2017年   20185篇
  2016年   22648篇
  2015年   25770篇
  2014年   35173篇
  2013年   52439篇
  2012年   72034篇
  2011年   76187篇
  2010年   44693篇
  2009年   41164篇
  2008年   69371篇
  2007年   73740篇
  2006年   73984篇
  2005年   70888篇
  2004年   67527篇
  2003年   64525篇
  2002年   62318篇
  2001年   109258篇
  2000年   112252篇
  1999年   94058篇
  1998年   25394篇
  1997年   22652篇
  1996年   22338篇
  1995年   21161篇
  1994年   19557篇
  1993年   18386篇
  1992年   72874篇
  1991年   70821篇
  1990年   69149篇
  1989年   66024篇
  1988年   60539篇
  1987年   59254篇
  1986年   56078篇
  1985年   53211篇
  1984年   39356篇
  1983年   33412篇
  1982年   19372篇
  1979年   35596篇
  1978年   24725篇
  1977年   21051篇
  1976年   19575篇
  1975年   20982篇
  1974年   25137篇
  1973年   24552篇
  1972年   22931篇
  1971年   21397篇
  1970年   19809篇
  1969年   18542篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
The question of the necessity of in-patient facilities of the area of (child and) adolescent neuropsychiatry is to be discussed further. The extremely optimistic views on this question of approximately 20 years ago cannot be maintained for the examined area and the examination time. In the LNKH Valduna/Vorarlberg, an establishment that was intended exclusively for adults until 1987, from 1980-1984 (evaluated in detail) and from 1984-1987 a further 60 minors were admitted. The exact evaluation shows that the conspicuousnesses of behaviour of a main group was so clear each time that it could not be treated elsewhere and certainly not in outpatient facilities. In the examined group the amount of patients with behaviour and socialization disorders outweighed by far the psychoses, also a high percentage of patients was multi morbid and/or had multiple handicaps. The resulting conclusion seems to us to be the necessity of setting-up a specific in-patients treatment unit for this group of patients with sufficient infrastructure.  相似文献   
992.
For a systematic understanding of the effect of diving on hearing ability and middle and inner ear morphology, we have carried out simulated tests on 65 healthy guinea pigs, under water 60 meters deep, and then decompress rapidly. The tests proved that hearing ability changed most significantly 7 days after diving. After diving, all tympanogram curves, except those in 3 ears, changed to type B. Thirty-nine (37.85%) middle ears had been damaged, 4 (3.88%) had inner ears injured, as seen under light microscope. During decompression, three animals had nystagmus. Screen electronmicroscopy showed hair cell destruction and hair derangement. Transmission electronmicroscopy showed mitochondria damage. The results showed that damages in middle and inner ears were mainly mechanical, sometimes metabolic.  相似文献   
993.
994.
995.
A case study of a family referred for clarification of cultural issues illustrates how a transcultural psychiatric service developed in the pediatric hospital setting can be used to advantage. A Vietnamese family with an inherited disorder. Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome, MPS VI), resisted genetic counseling and contraception. Three out of their six children were affected, one with a fatal outcome. The transcultural consultation offered an understanding of their behavior and facilitated subsequent management.  相似文献   
996.
Usher syndrome: clinical findings and gene localization studies   总被引:3,自引:0,他引:3  
The issue of genetic heterogeneity is a critical problem in the localization of the gene(s) for Usher syndrome. Based on the data obtained on families studied to date, the differences between type I and type II Usher syndrome appear quite distinct with regard to auditory and vestibular function. Although the majority of families can be confidently diagnosed as typical type I or type II, clinical investigations revealed four families with findings that did not fit into either of the two more common subtypes. These findings emphasize the critical importance of an in-depth clinical analysis concomitant with the linkage investigation to assure accurate subtyping of Usher syndrome. Based on an analysis of only those families with definite type I or type II Usher syndrome, approximately 17% of the genome can be excluded as a potential site of the gene for type I, and 14% can be excluded as the site for the type II gene. This study will continue until the Usher gene(s) is successfully localized.  相似文献   
997.
D L Marshall  A L Harvey 《Toxicon》1989,27(4):493-498
Venom from the scorpion Pandinus imperator potently and selectively blocks voltage-gated K+ channels in bullfrog neurones (Pappone, P. A. and Cahalan, M. D. 1987, J. Neurosci. 7, 3300-3305). Its effects on neuromuscular transmission have now been assessed. Twitch tension studies on chick biventer cervicis preparations showed that the venom (1 microgram/ml and above) significantly augmented responses to nerve but not muscle stimulation; there was little change in postjunctional sensitivity to cholinoceptor agonists or K+-induced depolarization. Electrophysiological studies on mouse triangularis sterni preparations revealed that the venom had no effect on spontaneous transmitter release, but increased evoked transmitter release. Extracellular recordings of nerve terminal action potentials showed that the venom selectively reduced the component of the waveform associated with K+ currents. These results confirm that this venom can selectively block neuronal K+ currents, and they show that this can facilitate the release of acetylcholine at the neuromuscular junction.  相似文献   
998.
Thirty cases of large pressure sores were treated by myocutaneous flaps (39 flaps) and the cure rate was 92%. Of them, 15 pressure sores were treated by gluteus maximus myocutaneous flaps, 12 in the greater trochanteric area by tensor fascia lata myocutaneous flaps, 7 in the ischiatic area by gracilis myocutaneous flaps and 4 in the ischiatic area biceps femoris myocutaneous flaps, 2 by a abductor hallucis myocutaneous flap and a flexor digitorum brevis myocutaneous flap. In author's opinion, myocutaneous flap transposition is simple, safe and reliable method in treating large pressure sores. These flaps increased the blood flow on recipient sites through its own intrinsic blood vessels so as to accelerate wound healing.  相似文献   
999.
Herniation of a thoracic disc in an acromegalic giant is reported. Degenerative changes in the spine in association with dorsal kyphosis, and the additional strain, resulted in the disc prolapse.  相似文献   
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