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   31283篇
  免费   2575篇
  国内免费   189篇
耳鼻咽喉   319篇
儿科学   1098篇
妇产科学   705篇
基础医学   3634篇
口腔科学   646篇
临床医学   2943篇
内科学   6664篇
皮肤病学   549篇
神经病学   2407篇
特种医学   1067篇
外科学   4687篇
综合类   813篇
一般理论   14篇
预防医学   2065篇
眼科学   1308篇
药学   2329篇
  1篇
中国医学   131篇
肿瘤学   2667篇
  2023年   218篇
  2022年   344篇
  2021年   738篇
  2020年   473篇
  2019年   697篇
  2018年   802篇
  2017年   569篇
  2016年   659篇
  2015年   754篇
  2014年   1032篇
  2013年   1212篇
  2012年   1984篇
  2011年   2045篇
  2010年   1190篇
  2009年   1037篇
  2008年   1790篇
  2007年   1746篇
  2006年   1615篇
  2005年   1545篇
  2004年   1549篇
  2003年   1374篇
  2002年   1221篇
  2001年   1130篇
  2000年   1025篇
  1999年   879篇
  1998年   322篇
  1997年   249篇
  1996年   224篇
  1995年   223篇
  1994年   206篇
  1993年   181篇
  1992年   516篇
  1991年   482篇
  1990年   443篇
  1989年   414篇
  1988年   371篇
  1987年   346篇
  1986年   337篇
  1985年   331篇
  1984年   226篇
  1983年   212篇
  1982年   144篇
  1981年   111篇
  1980年   115篇
  1979年   162篇
  1978年   99篇
  1977年   106篇
  1976年   74篇
  1974年   85篇
  1973年   71篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Seven patients with systemic lupus erythematosus (SLE), persistent thrombocytopenia (TP), in whom it was considered undesirable to institute an increase in steroid or immunosuppressive agents, were treated with danazol. Five patients completed the minimum period of 8 weeks. Two patients showed early response to danazol but were switched over to cyclophosphamide or azathioprine after 4 weeks because of systemic disease. Of the remaining five patients, four had complete responses. In one patient who failed treatment the TP was considered to be related to another drug (ranitidine). Other manifestations of SLE also improved with treatment. Side effects included amenorrhea in one patient, and hypoglycemia and hyponatremia in another. Infections were absent. Danazol can be a useful alternative treatment of lupus TP.  相似文献   
32.
This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney.  相似文献   
33.
Smooth muscle relaxant effect of dehydroindicolactone   总被引:1,自引:0,他引:1  
Dehydroindicolactone, a novel linear furanocoumarin with an 8-substituted side chain carrying a 5-member ring lactone, showed spasmolytic activity in a number of smooth muscle preparations. The spasmolytic activity seems to lie in its ability to block the dihydropyridine-sensitive calcium channel.  相似文献   
34.
4 cases of syringomyelia with type I Arnold Chiari malformation was seen presenting mainly with dissociated sensory loss, weakness of hands and upper motor neurone signs in the lower limbs. The first patient improved with posterior fossa decompression. The second and fourth patient appeared not to have improved after surgery, and the third case refused operation. One patient showed cord atrophy on myelogram presumably due to a collapse of the syrinx. One of the patients was unusual in that the syrinx extended down to segment T11. Magnetic resonance imaging of the posterior fossa and the cervical cord, to date, is the most useful procedure for diagnosis.  相似文献   
35.
Twenty-four nonsmoking male volunteers took 50 mg atenolol or 10 mg betaxolol orally once a day for 9 days in a two-period, four-sequence, randomized, crossover study. Plasma concentrations reached steady state after day 5. Percent fluctuation in plasma concentration defined as (Cmax-Cmin)/Cavg (% fluctuation 1) was 97% on day 9 for betaxolol and 343% for atenolol; thus atenolol fluctuation was more than threefold that of betaxolol. A 10-fold difference in plasma level fluctuation was observed when fluctuation was defined as (Cmax-Cmin)/Cmin (% fluctuation 2). The intersubject variances for % fluctuation 1 and % fluctuation 2 were 4.1 and 85.5 times greater for atenolol than for betaxolol; these differences were marginally statistically significant for % fluctuation 1 and significant for % fluctuation 2. The intrasubject variabilities for area under the curve and plasma level fluctuations were statistically greater for atenolol than for betaxolol. Atenolol intrasubject variances were 25 and 271 times greater than for betaxolol for % fluctuation 1 and % fluctuation 2, respectively. Thus, betaxolol exhibited less fluctuation in plasma levels with substantially less intersubject and intrasubject variability. These factors would be expected to provide a more consistent therapeutic response and more dependable dosage adjustment.  相似文献   
36.
A 49-year-old Chinese male with spontaneous intracerebral haemorrhage due to cerebral amyloid angiopathy is presented. This is the first case reported in the Chinese population, and the youngest patient described without a family history or associated mental disorder.  相似文献   
37.
Coagulase negative staphylococci have long been thought to be harmless skin commensals. However they are now recognised as important pathogens in patients who have undergone insertion of prosthetic devices. We present three patients with infection following the insertion of silicone polymer prostheses, in whom a coagulase negative staphylococcus was the pathogen. All responded to antibiotic treatment. It is important to alert the bacteriologist to the presence of an implanted prosthesis when wound swabs are sent from an area showing clinical signs of infection. The coagulase negative staphylococci may otherwise be regarded falsely as merely skin contaminants.  相似文献   
38.
We measured CBF and the CMRglc in normal controls and in patients with severe liver disease and evidence for minimal hepatic encephalopathy using positron emission tomography. Regions were defined in frontal, temporal, parietal, and visual cortex; the thalamus; the caudate; the cerebellum; and the white matter along with a whole-slice value obtained at the level of the thalamus. There was no difference in whole-slice CBF and CMRglc values. Individual regional values were normalized to the whole-slice value and subjected to a two-way repeated measures analysis of variance. When normalized CBF and CMRglc values for regions were compared between groups, significant differences were demonstrated (F = 5.650, p = 0.00014 and F = 4.58, p = 0.0073, respectively). These pattern differences were due to higher CBF and CMRglc in the cerebellum, thalamus, and caudate in patients and lower values in the cortex. Standardized coefficients extracted from a discriminant function analysis permitted correct group assignment for 95.5% of the CBF studies and for 92.9% of the CMRglc studies. The similarity of the altered pattern of cerebral metabolism and flow in our patients to that seen in rats subjected to portacaval shunts or ammonia infusions suggests that this toxin may alter flow and metabolism and that this, in turn, causes the clinical expression of encephalopathy.  相似文献   
39.
Geographic clustering of human T cell lymphoma/leukaemia virus type 1 (HTLV-1) infection is well recognised, particularly in south western Japan, parts of West and Central Africa, the south eastern United States and the Caribbean islands. Sporadic cases have been reported in many other parts of the world. The first case of HTLV-1 associated leukaemia/lymphoma (ATLL) in South East Asia is reported. Contact tracing showed a high incidence of carriers among the relatives.  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