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   367742篇
  免费   282883篇
  国内免费   37104篇
耳鼻咽喉   3550篇
儿科学   7615篇
妇产科学   4840篇
基础医学   106358篇
口腔科学   5598篇
临床医学   68442篇
内科学   117487篇
皮肤病学   6739篇
神经病学   33982篇
特种医学   13726篇
外国民族医学   16篇
外科学   56465篇
综合类   52116篇
现状与发展   1篇
一般理论   110篇
预防医学   55654篇
眼科学   20207篇
药学   65063篇
  3篇
中国医学   46908篇
肿瘤学   22849篇
  2021年   5108篇
  2020年   7295篇
  2019年   15234篇
  2018年   16283篇
  2017年   16591篇
  2016年   15315篇
  2015年   15467篇
  2014年   16161篇
  2013年   17230篇
  2012年   19664篇
  2011年   21276篇
  2010年   20336篇
  2009年   28144篇
  2008年   18451篇
  2007年   15183篇
  2006年   14402篇
  2005年   14017篇
  2004年   15114篇
  2003年   14117篇
  2002年   13900篇
  2001年   15656篇
  2000年   11287篇
  1999年   15944篇
  1998年   15009篇
  1997年   14628篇
  1996年   15764篇
  1995年   15770篇
  1994年   15445篇
  1993年   14173篇
  1992年   15240篇
  1991年   14412篇
  1990年   13267篇
  1989年   12980篇
  1988年   12409篇
  1987年   11536篇
  1986年   10955篇
  1985年   9975篇
  1984年   7638篇
  1983年   7469篇
  1982年   8092篇
  1981年   7571篇
  1980年   7164篇
  1979年   7480篇
  1978年   6342篇
  1977年   6550篇
  1976年   6072篇
  1975年   5827篇
  1974年   5467篇
  1973年   5176篇
  1972年   5134篇
排序方式: 共有10000条查询结果,搜索用时 70 毫秒
31.
Adverse ocular effects associated with niacin therapy.   总被引:2,自引:0,他引:2       下载免费PDF全文
In a retrospective survey of patients taking medication for hyperlipidaemia, those taking niacin (nicotinic acid) were more likely (p < 0.05) to report sicca syndromes, blurred vision, eyelid oedema, and macular oedema compared with those who never took niacin. Additionally, 7% of those taking niacin discontinued the drug owing to adverse ocular side effects, while none of the other lipid lowering agents were found to cause these side effects (p = 0.016). Data from spontaneous reporting systems support a possible association of decreased vision, cystoid macular oedema, sicca-like symptoms, discoloration of the eyelids with or without periorbital or eyelid oedema, proptosis, loss of eyebrow or eyelashes, and superficial punctate keratitis with the use of niacin in high doses. Decreased vision may be marked, and if the drug is not discontinued, may progress to cystoid macular oedema. All ocular side effects listed above are reversible if the association with niacin is recognised and the drug is discontinued; both the incidence and severity of the ocular side effects seem to be dose dependent.  相似文献   
32.
33.
34.
35.
36.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben.  相似文献   
37.
38.
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated.  相似文献   
39.
Summary— KR31080 (2-butyl-5-methyl-6-(1-oxopyridin-2-yl)-3-[[2'-(1H-tetrazol-5-yl) biphenyl-4-yl]methyl]-3H-imidazo[4,5-b] pyridine) is a potent inhibitor of angiotensin type 1 (AT1) receptors in rabbit aorta and human recombinant AT1 receptors. In the isolated rabbit thoracic aorta, KR31080 caused a nonparallel shift to the right of the concentration-response curves to angiotensin II (All) with decreased maximal response (pD'2 = 10.1 ± 0.1), but had no effect on the contractile response induced by norepinephrine. KR31080 inhibited specific [125I]AII binding to rabbit aortic membranes (AT, receptors) and [125I][Sar1, Ile8]AII binding to human recombinant AT1 receptors in a concentration-dependent manner with IC50 values of 0.84 ± 0.08 nM and 1.92 ± 0.15 nM, respectively, but did not inhibit specific [125I)AII binding to bovine cerebellum membranes (ÀT2 receptors). In the Scatchard analysis, KR31080 interacted with rabbit aortic AT1 receptors in a competitive manner, similar to losartan. These results demonstrate that KR31080 is a potent and AT1 selective angiotensin receptor antagonist which exerts a competitive antagonism in the [125I]AII binding assay and insurmountable AT1 receptor antagonism in the functional study.  相似文献   
40.
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