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   12868篇
  免费   1087篇
  国内免费   45篇
耳鼻咽喉   136篇
儿科学   457篇
妇产科学   308篇
基础医学   1732篇
口腔科学   492篇
临床医学   1471篇
内科学   2398篇
皮肤病学   157篇
神经病学   994篇
特种医学   654篇
外国民族医学   1篇
外科学   2154篇
综合类   195篇
一般理论   7篇
预防医学   1158篇
眼科学   301篇
药学   560篇
中国医学   9篇
肿瘤学   816篇
  2021年   167篇
  2020年   104篇
  2019年   138篇
  2018年   207篇
  2017年   186篇
  2016年   185篇
  2015年   254篇
  2014年   345篇
  2013年   465篇
  2012年   548篇
  2011年   526篇
  2010年   395篇
  2009年   362篇
  2008年   476篇
  2007年   575篇
  2006年   548篇
  2005年   428篇
  2004年   484篇
  2003年   469篇
  2002年   456篇
  2001年   409篇
  2000年   429篇
  1999年   385篇
  1998年   224篇
  1997年   191篇
  1996年   231篇
  1995年   169篇
  1994年   189篇
  1993年   134篇
  1992年   302篇
  1991年   293篇
  1990年   261篇
  1989年   279篇
  1988年   242篇
  1987年   243篇
  1986年   263篇
  1985年   269篇
  1984年   213篇
  1983年   136篇
  1982年   106篇
  1981年   103篇
  1980年   81篇
  1979年   166篇
  1978年   110篇
  1977年   104篇
  1976年   106篇
  1975年   92篇
  1974年   103篇
  1972年   100篇
  1971年   81篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice.  相似文献   
12.
13.
14.
15.
Sett  P. K.  Crockard  H. A.  Powell  M.  Lightman  S.  Jacobs  H. 《Acta neurochirurgica》1990,102(1-2):69-72
Summary Two cases of meningiomas, which are considered to have been caused by the preceding irradiation, are reported. In both cases, the cytokinetic study of the tumour using bromodeoxyuridine (BrdU) was performed. The percent of the tumour cells in the S phase of the cell cycle was less than 1% in both cases. The low labelling indices might suggest a relatively slow growing potential of these tumours, though the radiation-induced meningiomas were reported as being rapidly growing and malignant.  相似文献   
16.
Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.  相似文献   
17.
18.
Gastrointestinal dysfunction among intensive care unit patients   总被引:3,自引:0,他引:3  
This study used the Acute Physiological and Chronic Health Evaluation (APACHE II) system to select two groups of ICU patients with comparable risk of hospital death to evaluate the importance of GI dysfunction, defined as failure to tolerate enteral nutrition (EN), as a prognostic factor. In our ICU, patients who have not undergone recent bowel surgery are treated by EN. Those patients who cannot tolerate EN are treated by total parenteral nutrition (TPN). One hundred and eleven patients who tolerated EN (functioning gut) and 97 TPN patients who failed to tolerate EN (GI dysfunction) were studied. The mean APACHE II scores of the two groups were 17.7 +/- 6.5 (SD) and 17.7 +/- 5.1, respectively. The observed mortality of patients with GI dysfunction (51%) was significantly higher (p less than .0005) than that of patients with a functioning gut (25%). This was associated with significantly poorer APACHE II mean BP, oxygenation, and creatinine scores among the GI dysfunction patients. Our results suggest that shock, ischemia, and hypoxemia, in addition to causing impairment of renal function, may bring about changes in the GI tract, evident clinically only as a failure to tolerate EN, which have an adverse effect on the prognosis of ICU patients so affected.  相似文献   
19.
20.
Critical to survival is the geriatric concept, allostasis, defined as the ability to achieve stability through change. It is appropriate that allostasis is an introduction to this commentary, which may partially apply to the medical and pharmacy profession as currently constituted.  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