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   1783830篇
  免费   123465篇
  国内免费   2575篇
耳鼻咽喉   25430篇
儿科学   54414篇
妇产科学   46967篇
基础医学   256099篇
口腔科学   51708篇
临床医学   158689篇
内科学   338881篇
皮肤病学   39090篇
神经病学   137267篇
特种医学   69646篇
外国民族医学   276篇
外科学   275913篇
综合类   36609篇
现状与发展   2篇
一般理论   476篇
预防医学   125372篇
眼科学   42060篇
药学   140994篇
  10篇
中国医学   4421篇
肿瘤学   105546篇
  2018年   18272篇
  2017年   14288篇
  2016年   16161篇
  2015年   18148篇
  2014年   24672篇
  2013年   36194篇
  2012年   49764篇
  2011年   52435篇
  2010年   30889篇
  2009年   29241篇
  2008年   49530篇
  2007年   52497篇
  2006年   53495篇
  2005年   51174篇
  2004年   49220篇
  2003年   47201篇
  2002年   45711篇
  2001年   96962篇
  2000年   99762篇
  1999年   82967篇
  1998年   20625篇
  1997年   18191篇
  1996年   18212篇
  1995年   17139篇
  1994年   15692篇
  1993年   14702篇
  1992年   62865篇
  1991年   60557篇
  1990年   59063篇
  1989年   56913篇
  1988年   51862篇
  1987年   50451篇
  1986年   47328篇
  1985年   45129篇
  1984年   32693篇
  1983年   27568篇
  1982年   14977篇
  1981年   13101篇
  1979年   29455篇
  1978年   19974篇
  1977年   17477篇
  1976年   15314篇
  1975年   17192篇
  1974年   20301篇
  1973年   19501篇
  1972年   18588篇
  1971年   17460篇
  1970年   16328篇
  1969年   15465篇
  1968年   13992篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
We report our experience of eight cases of isolated full thickness burns of the penis. Early excision of burns of the penile shaft and repair with a preputial flap or mesh split skin graft produces excellent results, with a reduction in complications and an early re-establishment of sexual function. Conservative treatment of burns of the glans, on the other hand, is appropriate and results in minimal scarring.  相似文献   
94.
Computed tomography (CT) is currently the imaging modality of choice for assessing the morphology of the adrenal glands in adult patients. Much useful information can be gained using CT in disease processes which primarily involve one or both of the adrenal glands, such as adenomas, as well as in entities which secondarily affect the adrenals, such as pituitary or metastatic disease. The size and configuration of the glands can be readily determined, and masses may be detected. We discuss CT of normal and abnormal adrenal glands with sonographic (US) and pathological correlation, when available. Entities which may mimic adrenal abnormalities are emphasized. Relative advantages of US over CT in the pediatric patient are discussed.  相似文献   
95.
The Dundee Memory Clinic was established in 1991. This paper reviews the diagnosis of the first 150 attenders and compares the findings with those of other memory clinics.  相似文献   
96.
Fibroblasts incorporated within collagen gels induce a cell-mediated contraction of the gel to form a three-dimensional, tissue-like structure by a mechanism thought to mimic wound contraction in vivo . In this study a gel contraction model was used to investigate the ability of fibroblasts derived from adult gingiva, adult skin and fetal skin to organise a collagen matrix. In addition the effects of interleukin-1β (IL-1β) on the contraction process was also investigated. Over the concentration range 5-50 U/ml, IL-1β induced a statistically significant inhibition of gel contraction in all fibroblast cell types ( P <0.05), although fetal fibroblasts appeared least responsive and gingival fibroblasts most responsive to the inhibitory effects of this cytokine. Comparison of gel contraction by the different fibroblast strains indicated that fetal and gingival fibroblasts shared similar contraction kinetics. For the adult skin fibroblasts, three of five strains studied showed significantly diminished levels of gel contraction compared to fetal and gingival cells. This apparent difference in fibroblast phenotype may, at least in part, explain the fetal-like wound healing pattern seen in the oral mucosa.  相似文献   
97.
98.
Choristomas, masses of normal tissues in aberrant locations, contain smooth muscle fibers and fibrous tissues. We describe the MR imaging features of two choristomas located in the internal auditory canals and arising from the facial and vestibulocochlear nerves. Both lesions enhanced with contrast material. In one case, enhancement was seen in the geniculate ganglion and greater superficial petrosal nerve. In the other, a medial component enhanced less than the lateral component did.  相似文献   
99.
The ability of three Porphyromonas spp., seven Prevotella spp., seven Fusobacterium spp. and two related Bacteroides spp. (B. levii and B. macacae) to degrade an extensive range of synthetic endo-, amino- and diamino peptidase substrates linked to the fluorescent leaving group 7-amido-4-methylcoumarin (NHMec) was investigated. Many more species than was previously recognized exhibited peptidase activities, albeit at lower levels than those already described for Porphyromonas gingivalis. Detection of chymotrypsin-like activity was dependent on which of three NHMec-linked substrates was used, but all species exhibited degradative activity with at least one of these substrates. Elastase-like activity was detected in all species though not all species reacted with each of the elastase substrates. Glycylprolyl peptidase activity was detected in all of the species tested with the exception of F. mortiferum, F. gonidiaformans, F. naviforme and F. necrophorum. While the detection of peptidase activities does not appear to be useful for the differentiation of species within the genera Bacteroides and Prevotella, its ability to differentiate species of the genus Porphyromonas or Fosobacterium further investigation.  相似文献   
100.
The diagnosis of acute disseminated encephalomyelitis (ADEM) is frequently missed or delayed with consequent delay in instituting therapy in the crucial phase of the illness. The role of MRI in the diagnosis of ADEM is well established, however, the value of its early utilization of treatment on the outcome of patients has not been adequately stressed. Three patients with ADEM are described. Delay in the diagnosis of the first was associated with severe sequelae, while in the other two early diagnosis and institution of corticosteroid therapy which was facilitated by MRI, was associated with a better outcome. MRI should be carried out early once the diagosis of ADEM is entertained.  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