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   34707篇
  免费   3678篇
  国内免费   42篇
耳鼻咽喉   206篇
儿科学   1113篇
妇产科学   966篇
基础医学   4883篇
口腔科学   711篇
临床医学   4176篇
内科学   6278篇
皮肤病学   552篇
神经病学   3027篇
特种医学   1505篇
外国民族医学   3篇
外科学   4419篇
综合类   769篇
一般理论   43篇
预防医学   4247篇
眼科学   882篇
药学   2591篇
中国医学   45篇
肿瘤学   2011篇
  2022年   271篇
  2021年   611篇
  2020年   327篇
  2019年   573篇
  2018年   600篇
  2017年   464篇
  2016年   514篇
  2015年   545篇
  2014年   769篇
  2013年   1139篇
  2012年   1631篇
  2011年   1596篇
  2010年   947篇
  2009年   847篇
  2008年   1448篇
  2007年   1542篇
  2006年   1531篇
  2005年   1470篇
  2004年   1435篇
  2003年   1342篇
  2002年   1277篇
  2001年   1190篇
  2000年   1203篇
  1999年   1032篇
  1998年   441篇
  1997年   392篇
  1996年   364篇
  1995年   315篇
  1994年   340篇
  1993年   334篇
  1992年   817篇
  1991年   782篇
  1990年   770篇
  1989年   683篇
  1988年   704篇
  1987年   664篇
  1986年   609篇
  1985年   670篇
  1984年   537篇
  1983年   417篇
  1982年   267篇
  1981年   287篇
  1979年   465篇
  1978年   348篇
  1977年   264篇
  1976年   275篇
  1975年   261篇
  1974年   285篇
  1973年   261篇
  1972年   268篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
Bile acid receptors in colorectal cancer   总被引:4,自引:0,他引:4  
Bile acids are thought to be involved in both the aetiology and development of colorectal cancer. In this study the existence of specific bile acid receptor proteins has been postulated. A receptor assay which involved labelling with 14C-deoxycholic acid was performed as well as autoradiography using 3H-deoxycholic acid. In an initial study resected colorectal cancer and adjacent histologically normal colorectal mucosa from 39 patients were studied, as were samples of normal gastric mucosa, cancers and benign colorectal tumours. Specific receptors to deoxycholic acid were detected in 12 (30.8 per cent) of the colorectal cancers, but in only 1 (2.6 per cent) of the samples from normal colorectal mucosa (X2 = 11.16, P less than 0.005). No deoxycholic acid receptors were detected in any other tissue studied. Autoradiographs of colorectal cancers showed binding of 3H-deoxycholic acid in receptor-positive tumour tissue. These findings might provide some explanation for the evidence linking bile acids with the disease.  相似文献   
84.
85.
Ivermectin is a recently developed macrocyclic lactone that has widespread antiparasitic activity. A series of clinical trials has shown that ivermectin is safe and effective in the treatment of human infection with Onchocerca volvulus. Although it is rapidly microfilaricidal, it does not cause a severe reaction as is seen with diethylcarbamazine treatment. The drug also temporarily interrupts production of microfilaria but has no known long-lasting effects on the adult worms. In patients with onchocerciasis, a single oral dose of ivermectin (150 micrograms/kg) repeated once a year leads to a marked reduction in skin microfilaria counts and ocular involvement. At this dose, ivermectin causes minimal side effects and appears to be sufficiently free of severe adverse reactions to be used on a mass scale. Its use promises to revolutionise the treatment of onchocerciasis.  相似文献   
86.
Sixty-seven patients with melancholia and 42 normal controls were tested with a battery of neuropsychological tasks selected to assess regional cortical functioning in both hemispheres. Compared with controls, melancholics exhibited a pattern of bifrontal and right parietal impairment, which was independent of age, sex, handedness and drug administration. These findings confirm and extend prior studies and contrast with those we and others have reported in patients with schizophrenia.  相似文献   
87.
Immunohistochemical staining of conjunctival biopsies from cynomolgus monkeys (Macaca fascicularis) was performed after they received a single primary ocular infection, a single secondary challenge infection, or repeated ocular inoculations with Chlamydia trachomatis. T cells of the suppressor/cytotoxic (OKT8F) phenotype predominated regardless of the infection protocol, and perifollicular T lymphocytes of both the suppressor/cytotoxic and helper (OKT4A) phenotypes appeared in large numbers during the peak inflammatory reaction. In repeatedly inoculated monkeys, T cells and follicles persisted until cessation of reinfection. IgM-bearing B lymphocytes comprised the majority of cells within follicles, with smaller numbers of IgG- or IgA-positive B cells. The major difference in the response to the various infection protocols was the increased number and persistence of follicles with repeated reinoculation. The finding of large numbers of T-suppressor/cytotoxic and T-helper cells in the infected conjunctiva supports a role for cell-mediated immunity in the local response to C. trachomatis ocular infection.  相似文献   
88.
89.
90.
Digital nerve injuries in the hand are common and can result in significant impairment and functional restriction. Despite this, there is relatively little literature, particularly with respect to postoperative rehabilitation. Splinting after repair, purported to protect the repaired nerve from excessive stretch is still commonly used. Recent cadaveric studies indicate postoperative rehabilitation is not necessary with resection up to 2.5mm. A randomized controlled trial was therefore undertaken to determine whether splinting after isolated 5th degree digital nerve transection is in fact necessary. Twenty-six subjects were recruited over a two-year period and randomized to either three weeks of hand-based splinting or free active motion. ANCOVA indicated no differences in sensibility at six months between the two groups. Subjects also reported their greatest functional limitations were because of hyperesthesia. Although this study is underpowered, these limited results suggest splinting may not be required postoperatively.  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