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   2375017篇
  免费   194610篇
  国内免费   4209篇
耳鼻咽喉   34264篇
儿科学   72746篇
妇产科学   62928篇
基础医学   334865篇
口腔科学   67522篇
临床医学   215511篇
内科学   468563篇
皮肤病学   47930篇
神经病学   200773篇
特种医学   95956篇
外国民族医学   886篇
外科学   360380篇
综合类   56217篇
现状与发展   1篇
一般理论   977篇
预防医学   190597篇
眼科学   55462篇
药学   177519篇
  4篇
中国医学   4365篇
肿瘤学   126370篇
  2018年   24203篇
  2016年   20575篇
  2015年   23278篇
  2014年   33532篇
  2013年   50827篇
  2012年   68733篇
  2011年   72271篇
  2010年   42470篇
  2009年   40861篇
  2008年   68754篇
  2007年   73092篇
  2006年   73993篇
  2005年   72032篇
  2004年   69331篇
  2003年   67010篇
  2002年   66257篇
  2001年   112449篇
  2000年   116524篇
  1999年   98333篇
  1998年   27858篇
  1997年   25522篇
  1996年   25447篇
  1995年   24609篇
  1994年   23159篇
  1993年   21552篇
  1992年   79386篇
  1991年   76393篇
  1990年   73575篇
  1989年   70841篇
  1988年   65846篇
  1987年   64800篇
  1986年   61334篇
  1985年   58399篇
  1984年   44222篇
  1983年   37657篇
  1982年   22886篇
  1981年   20332篇
  1980年   19034篇
  1979年   41299篇
  1978年   28985篇
  1977年   24346篇
  1976年   22832篇
  1975年   23964篇
  1974年   29638篇
  1973年   28042篇
  1972年   26226篇
  1971年   24151篇
  1970年   22752篇
  1969年   21087篇
  1968年   19135篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Eleven patients with bronchial epidermoid carcinoma and undergoing treatment with cis-D.D.P. (II) were kept under electrophysiological and clinical surveillance. No other neurotoxic medication was added. The total dose of cis-D.D.P. was 300 mg/m2 over a period of three months: namely, three courses of 100 mg/m2 distributed over 5 days. Following the pretreatment check-up, the patients were divided into two groups: those without any electrophysiological abnormality (group A), and those without clinical abnormality but with a delayed latency H of the Hoffmann Reflex (group B). Patients in group A showed a slowing down of the motor nerve conduction velocity of the Median and Peroneal Nerves after a course of 100 mg, without accompanying worsening of the conduction velocity after 300 mg/m2, and prolongation of the distal latency of the sensory Median Nerve after 300 mg/m2; in group B, no significant change of electrophysiological clinical features were noted. In the two groups a non-significant reduction in amplitude of evoked responses were noted. These findings are more consistent with an axonal injury than with functional myelin injury. The authors review the existing literature and discuss the physiopathologic mechanisms of cis-D.D.P. peripheral neuropathies.  相似文献   
992.
Repeated testing attenuates conditioned place preference with cocaine   总被引:2,自引:2,他引:0  
Cocaine-treated rats acquired a preference for cocaine-associated contextual stimuli (CS) relative to saline-injected control rats. However, when animals were given repeated tests for conditioned place preference intermittent between conditioning trials, they displayed an attenuation in strength of conditioning. This attenuation was not due to pharmacologic tolerance (Experiment 1), but rather reflected a disruption in learning due to exposure to the CS alone (Experiment 2). Like other examples of classical conditioning, the strength of the conditioned response (CR) as assessed by the conditioned place preference model may be influenced by partial reinforcement.  相似文献   
993.
Western transfer and immunoenzymatic staining with affinity-purified monospecific antiserum was used to detect a 38-Kd protein that bound to native and denatured DNA cellulose. This protein has previously been shown to be a delayed early herpes simplex virus type-2 specific protein.  相似文献   
994.
995.
996.
4260 conjunctival specimens of 2850 outpatients with keratoconjunctivitis of presumed infectious etiology were studied. Two thousand six hundred sixty-eight specimens (63%) revealed growth of bacteria, and 80 (2%) growth of fungi. One hundred ninety-nine specimens (5%) were McCoy cell culture or direct stain (monoclonal antibody or Giemsa) positive for Chlamydia trachomatis. two patients had a C. psittaci infection (ELISA techniques). In patients with keratoconjunctivitis of bacterial etiology, overall incidence of McCoy cell culture-proven chlamydial infections was 7%; in the 20 to 30-year age group it was 12.5%. Simultaneous infections of chlamydiae and other bacteria were seen in 34 patients. Since sensitive and specific tests to diagnose chlamydial infections are available, ophthalmologists may be able to prevent these infections by agent-specific antibiotic therapy.  相似文献   
997.
The Brief Symptom Inventory (BSI), a 53-item psychiatric symptom checklist, was administered to 57 alcoholic inpatients on days 2, 10, 18 and 26 of their 28-day stay in an alcoholism rehabilitation unit at a Veterans Administration hospital. The results of the test show a steady decline in the patients' psychiatric symptomatology from week 1 to week 4 with the most dramatic improvement evidenced between weeks 1 and 2.  相似文献   
998.
999.
The in vitro activities of beta-lactam antibiotics against Bacteroides fragilis and B. fragilis group isolates are presented. Clinical isolates from 1986 were compared with strains from 1979 to 1982. Imipenem, ticarcillin-clavulanic acid, and ceftizoxime were the most active agents. Cefotetan was equivalent to cefoxitin against B. fragilis but less active against B. fragilis group isolates. Enhancement of cefotaxime by its desacetyl metabolite was minimal.  相似文献   
1000.
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