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   2117篇
  免费   155篇
  国内免费   75篇
耳鼻咽喉   2篇
儿科学   171篇
妇产科学   41篇
基础医学   268篇
口腔科学   58篇
临床医学   265篇
内科学   537篇
皮肤病学   77篇
神经病学   63篇
特种医学   395篇
外科学   106篇
综合类   46篇
预防医学   101篇
眼科学   20篇
药学   86篇
  2篇
肿瘤学   109篇
  2023年   4篇
  2022年   3篇
  2021年   12篇
  2020年   15篇
  2019年   16篇
  2018年   33篇
  2017年   24篇
  2016年   22篇
  2015年   46篇
  2014年   49篇
  2013年   61篇
  2012年   46篇
  2011年   46篇
  2010年   91篇
  2009年   90篇
  2008年   57篇
  2007年   94篇
  2006年   59篇
  2005年   65篇
  2004年   28篇
  2003年   22篇
  2002年   29篇
  2001年   41篇
  2000年   36篇
  1999年   33篇
  1998年   128篇
  1997年   157篇
  1996年   135篇
  1995年   112篇
  1994年   116篇
  1993年   101篇
  1992年   30篇
  1991年   39篇
  1990年   39篇
  1989年   56篇
  1988年   47篇
  1987年   46篇
  1986年   52篇
  1985年   49篇
  1984年   30篇
  1983年   17篇
  1982年   27篇
  1981年   30篇
  1980年   27篇
  1979年   6篇
  1978年   10篇
  1977年   20篇
  1976年   25篇
  1975年   16篇
  1970年   2篇
排序方式: 共有2347条查询结果,搜索用时 15 毫秒
951.
952.
953.
BACKGROUND: Childhood experiences profoundly affect later functioning asan adult. Family practitioners are well-placed to discover thelinks between childhood troubles and later somatization, depressionor anxiety. OBJECTIVES: We aimed to study the interrelation of somatization, depressiveand anxiety disorders in frequently attending patients in generalpractice; to investigate whether these problems are relatedto a childhood history of illness experiences, deprivation,life events and abuse; and to determine the independent contributionsof these childhood factors to the prediction of adult somatization,depressive and anxiety disorders. METHODS: One hundred and six adult general practice patients with highconsultation frequency were studied. Somatization was operationalizedas a more comprehensive version of DSM-III-R somatization disorder(5 complaints; SSI 5/5). For depression (ever depressive and/ordysthymic) and anxiety (panic, phobias and/or generalized anxiety)DSM-III-R criteria were used. Using a structured questionnairewe assessed illness experiences, deprivation of parental care,abuse (sexual/physical) and other life events before age 19. RESULTS: The overlap between somatization, depression and anxiety waslargely accounted for by 16 patients with a triple problem:somatization and depression and anxiety. Somatization was specificallyrelated to deprivation, depression to other life events. Abuse(prevalence 16%) independently predicted psychiatric problemsin general. Youth experiences before age 12 were most important. CONCLUSIONS: The high prevalence of triple problems suggests a need to reconsiderconcepts like somatic anxiety and anxious depression. The specificityof the relation between deprivation and somatization and ofthe relation between other life events and depression indicatesthat distinct causal mechanisms (in youth) contribute to theseproblems. Keywords. Parental deprivation, child abuse, somatoform disorders, depressive disorders, anxiety disorders.  相似文献   
954.
955.
The effects of 3 phosphodiesterase (PDE) inhibitors, rolipram (PDE IV), milrinone (PDE III) and theophylline (non-selective) on PAF (50 ng kg-1; iv)-induced airway vascular leakage have been evaluated in guinea-pigs. Rolipram (3-300 micrograms kg-1; iv) reduced the increase in permeability induced by PAF at all airway levels whereas milrinone (10-1000 micrograms kg-1; iv) and theophylline (30 mg kg-1; iv) were without effects. The anti-leakage activity of rolipram may be of therapeutic value in asthma.  相似文献   
956.
Parmley  RT; Rice  WG; Kinkade  JM Jr; Gilbert  C; Barton  JC 《Blood》1987,70(5):1630-1638
A microgranule fraction, isolated from human neutrophils by using a novel high-resolution Percoll density gradient system contained granules with the lowest density and diameter when compared with 12 other isopycnic granule fractions. Ultrastructurally, from 34% to 50% of the microgranules showed homogeneous diaminobenzidine (DAB) staining under conditions for localizing peroxidase reactivity. The presence of myeloperoxidase (MPO) was further confirmed by biochemical and spectral analysis and immunodiffusion methods. Periodate-thiocarbohydrazide- silver proteinate (PA-TCH-SP) intensely stained vicinal glycols in the matrix of greater than 97% microgranules in contrast to the weak or absent staining seen in larger primary granules. Directly sampled segmented neutrophils contained small DAB- and PA-TCH-SP-positive granules, which often appeared in clusters. These DAB-positive microgranules selectively remained within the cells after stimulation of exocytosis with the calcium ionophore A23187. The enriched DAB- positive microgranule fraction recovered from A23187-treated cells also contained lysozyme and beta-glucuronidase but lacked vitamin B12 binding protein activity. A similar small, DAB- and PA-TCH-SP-positive granule type was also identified in normal promyelocytes and was the predominant or only granule type observed in leukemic or preleukemic myeloid cells from four patients. This study demonstrates a unique subpopulation of MPO-containing microgranules in normal and leukemic human myeloid cells that are distinguished from (other) primary granules by their extremely low density, small size, content of complex carbohydrates, and resistance to secretion.  相似文献   
957.
958.
959.
960.
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