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   1625篇
  免费   100篇
  国内免费   3篇
耳鼻咽喉   8篇
儿科学   27篇
妇产科学   13篇
基础医学   258篇
口腔科学   45篇
临床医学   146篇
内科学   347篇
皮肤病学   34篇
神经病学   171篇
特种医学   70篇
外科学   209篇
综合类   5篇
预防医学   118篇
眼科学   8篇
药学   101篇
中国医学   5篇
肿瘤学   163篇
  2023年   8篇
  2022年   14篇
  2021年   45篇
  2020年   20篇
  2019年   28篇
  2018年   34篇
  2017年   29篇
  2016年   27篇
  2015年   40篇
  2014年   37篇
  2013年   65篇
  2012年   84篇
  2011年   88篇
  2010年   72篇
  2009年   43篇
  2008年   71篇
  2007年   66篇
  2006年   80篇
  2005年   89篇
  2004年   75篇
  2003年   65篇
  2002年   61篇
  2001年   45篇
  2000年   61篇
  1999年   53篇
  1998年   18篇
  1997年   22篇
  1996年   18篇
  1995年   15篇
  1994年   7篇
  1993年   11篇
  1992年   42篇
  1991年   25篇
  1990年   27篇
  1989年   27篇
  1988年   19篇
  1987年   24篇
  1986年   21篇
  1985年   19篇
  1984年   13篇
  1983年   11篇
  1982年   7篇
  1980年   7篇
  1979年   10篇
  1978年   9篇
  1977年   10篇
  1975年   6篇
  1974年   10篇
  1972年   7篇
  1969年   10篇
排序方式: 共有1728条查询结果,搜索用时 0 毫秒
1.
Testicular microlithiasis: sonographic and clinical features.   总被引:7,自引:0,他引:7  
Eleven cases of bilateral diffuse microlithiasis of the testes were evaluated sonographically. The presence of testicular microlithiasis was coincidental to the presence of testicular neoplasms (n = 2), nontesticular malignant lesion in the abdomen or chest (n = 2), subfertility (n = 2), varicocele (n = 1), epididymitis (n = 1), testicular maldescent (n = 1), scrotal trauma (n = 1), and transient scrotal pain (n = 1). Clinical follow-up suggested that testicular microlithiasis is an asymptomatic nonprogressive condition. Sonographic examination of testicular microlithiasis shows diffuse hyperechoic nonshadowing foci measuring 1-2 mm in diameter throughout both testes. The diagnosis of testicular microlithiasis was pathologically proved in five cases. In six cases, the diagnosis was made on the basis of the sonographic appearance (n = 6), clinical information and follow-up (n = 6), and radiologic demonstration of testicular microcalcifications (n = 3). The sonographic appearance of testicular microlithiasis is specific, and we believe that biopsy or orchiectomy in these cases is unnecessary.  相似文献   
2.
3.
4.
A surgical procedure in which a tendon graft is used to reconstruct the hood of the proximal interphalangeal joint for the correction of the postburn boutonnière deformity is described. The intent is to use the potential of the lateral bands for simultaneous extension of the interphalangeal joints, avoiding their excessive palmar displacement. The technique has been employed in 22 fingers with satisfactory results, except in the small finger.  相似文献   
5.
The soluble serotonin-binding proteins (SBP) present in bovine frontal cortex are very similar to those reported in rat brain. Binding of [3H]serotonin to SBP, present in ammonium sulphate-precipitated proteins from bovine cortex, requires Fe2+ but not Fe3+. In the presence of an optimal concentration of Fe2+ (0.1 mM), bovine SBP behave as a single class of non-cooperative sites for [3H]serotonin binding (Bmax = 120 +/- 12 pmol/mg protein, KD = 0.12 +/- 0.04 microM, n = 3). Binding of [3H]serotonin is decreased by nucleotides and by reagents which modify sulfhydryl groups and reduce disulfide bonds and by metal ion chelators. Serotonin analogs possessing an hydroxyl group on the indole ring and catecholamine analogs possessing an intact catechol moiety are effective competitors (Ki from 0.1 to 0.3 microM). In both cases, the aliphatic amino group does not contribute to the binding, but the affinity is strongly decreased if aromatic hydroxyl groups are methoxylated. Catecholamine-SBP interactions can also be demonstrated directly by binding experiments. Binding of [3H]dopamine is greatly enhanced by Fe2+, Cu2+ and Mn2+, but not by Fe3+. The Fe(2+)-dependent binding component of [3H]dopamine is saturable (Bmax = 279 +/- 64 pmol/mg protein, KD = 0.19 +/- 0.02 microM, n = 3), and possesses the same physicochemical properties as SBP: it elutes immediately after the void volume on a Sephacryl S100 HR (1.6 x 140 cm) gel filtration column (reflecting aggregation) and it migrates with an apparent molecular weight of 57-58 kDa on native polyacrylamide gel electrophoresis. Whereas the serotonin-storing role of SBP in serotonergic neurons has already been well documented, the present data advocate that these proteins may also possess catecholamine-storing properties.  相似文献   
6.
7.
Spectrum of NSD1 mutations in Sotos and Weaver syndromes   总被引:8,自引:0,他引:8  
Interestingly, mental retardation was consistently more severe in patients with NSD1 deletions. Macrocephaly and facial gestalt but not overgrowth and advanced bone age were consistently observed in Sotos syndrome patients. We suggest therefore considering macrocephaly and facial gestalt as mandatory criteria for the diagnosis of Sotos syndrome and overgrowth and advanced bone age as minor criteria.  相似文献   
8.
9.
A yellow-pigmented rod- to coccoid-shaped coryneform microorganism was isolated from the blood of a patient with acute myeloid leukemia. It was identified by 16S rRNA gene sequencing as a previously undescribed species of Janibacter. The isolate was susceptible to penicillins, aminoglycosides, fluoroquinolones, and glycopeptides.  相似文献   
10.
Rats isolated at the time of calcification of the incisors show, after 14-18 months of social deprivation, an increased number of alpha 1-adrenoceptors labeled with [3H]WB 4101, both in the striatum and in the vas deferens, as well as a decreased number of alpha 2-adrenoceptors labeled with [3H]-clonidine in the vas deferens. Social isolation does not, however, modify the density of [3H]clonidine binding sites in the cerebral cortex. The functional state of alpha-adrenoreceptors in the vas deferens from isolated rats appears to correlate with the binding studies since the isolated tissue is hypersensitive to the contractile effect of exogenous noradrenaline and subsensitive to the inhibitory effect of clonidine on the electrically stimulated preparation.  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