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   3222637篇
  免费   241327篇
  国内免费   8188篇
耳鼻咽喉   43751篇
儿科学   104679篇
妇产科学   87285篇
基础医学   462859篇
口腔科学   89532篇
临床医学   293194篇
内科学   630614篇
皮肤病学   73519篇
神经病学   258208篇
特种医学   124283篇
外国民族医学   748篇
外科学   489056篇
综合类   70647篇
现状与发展   14篇
一般理论   1172篇
预防医学   257509篇
眼科学   73556篇
药学   235946篇
  15篇
中国医学   5974篇
肿瘤学   169591篇
  2018年   35137篇
  2017年   26801篇
  2016年   30829篇
  2015年   34681篇
  2014年   48793篇
  2013年   73678篇
  2012年   97467篇
  2011年   104222篇
  2010年   63011篇
  2009年   60167篇
  2008年   97493篇
  2007年   104042篇
  2006年   105399篇
  2005年   102214篇
  2004年   97596篇
  2003年   94431篇
  2002年   91045篇
  2001年   146537篇
  2000年   150384篇
  1999年   126787篇
  1998年   38087篇
  1997年   33580篇
  1996年   34293篇
  1995年   33289篇
  1994年   30778篇
  1993年   28962篇
  1992年   101058篇
  1991年   98623篇
  1990年   95927篇
  1989年   92121篇
  1988年   85009篇
  1987年   83458篇
  1986年   78590篇
  1985年   75589篇
  1984年   56941篇
  1983年   48364篇
  1982年   29386篇
  1981年   26469篇
  1979年   52282篇
  1978年   37620篇
  1977年   31392篇
  1976年   29758篇
  1975年   31691篇
  1974年   37813篇
  1973年   35955篇
  1972年   33813篇
  1971年   31713篇
  1970年   29063篇
  1969年   27668篇
  1968年   25498篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
The family physician should follow the small premature infant in the neonatal intensive care center and review the baby's problems and risk factors. In the office, special attention is required in monitoring the infant. Proper hospital and office care greatly improve the prognosis.  相似文献   
992.
Laterality of cross-modal spatial processing   总被引:1,自引:0,他引:1  
This study examined the laterality of spatial-form perception in normal adults using a cross-modal matching paradigm involving visual and tactile processing. Randomly generated eight-point and 12-point Vanderplas and Garvin (1959) patterns were used as the stimuli. In a visual-to-tactile task, a lateralized visual pattern was followed immediately by a haptic task requiring subjects to discriminate which of two simultaneously felt shapes matched the visual pattern. In a tactile-to-visual task, subjects decided which of two simultaneously felt shapes matched a lateralized visual pattern presented after haptic manipulation. There were no main effects for laterality or for sex differences. Matching accuracy was better in the visual-to-tactile task and for less complex stimuli. A visual field by feeling hand interaction showed best recognition accuracy when visual-feeling hand combinations on the same side of the body were used in the two matching tasks. These data reflect a stimulus-response compatibility explanation of spatial-form perception that is consistent with a behavioral and not a cerebral asymmetry model.  相似文献   
993.
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   
994.
Principles of battlefield psychiatry   总被引:2,自引:0,他引:2  
  相似文献   
995.
This study investigated social interactions between infants and mothers, comparing dyads with physically disabled infants and dyads with nondisabled infants. The groups were matched on mental and motor development, sex, socioeconomic status, birth order, and maternal education. Each infant-mother dyad was videotaped at home during a 10-minute period of free play, and blind observers subsequently transcribed infants' and mothers' behaviors. In general, the groups were remarkably similar in their interaction patterns. However, a few differences emerged: Mothers of infants with physical disabilities were significantly more commanding than were comparison mothers. Nondisabled infants tended to engage in more eye contact than did infants with physical disabilities. And whereas mothers of nondisabled infants responded to interactive play with interactive play, mothers of infants with physical handicaps tended to respond with commands and verbalizations. These results suggest reciprocal influences between infants and mothers in both groups and highlight emerging maternal behavior patterns that may interfere with the development of communication and independence in handicapped young children.  相似文献   
996.
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   
997.
998.
Wheat germ agglutinin (WGA) was found to stimulate DNA synthesis in human peripheral blood mononuclear cells at relatively low concentrations and to inhibit DNA synthesis at higher concentrations. Both actions were inhibited by oligomers of N-acetyl-D-glucosamine. Significant mitogenic activity was dependent on the use of human (as opposed to fetal calf) serum to supplement the culture medium. Purified T cells responded to WGA very weakly and the incorporation of thymidine into non-T cells in response to WGA was less than the lectin-free control. The full ability of T cells to respond to WGA was restored by the addition of monocytes, but not by any other blood cells. Interleukin 2 partially restored the ability of T cells to respond to WGA; interleukin 1 was less effective. WGA displayed a strong synergistic action with the tumour promoter, 12-O-tetradecanoyl-13-acetate (TPA), in stimulating DNA synthesis in separated T (but not non-T) cell fractions, and in unfractioned mononuclear cells. These results reconcile most of the conflicting reports in the literature concerning the interaction of WGA with human lymphocytes.  相似文献   
999.
A cohort of 1163 pregnant women in two small towns in South Wales, UK, was identified and followed until the children born to them were five years of age. Growth in these children is described and a number of determinants identified. Social-class differences were very small at birth but differences in height became clear by the age of two years and in head circumference before this. In height the differences were largely accounted for by greater growth in social class I, but there was a gradient in head circumference throughout all the social classes. The social class effects gradually increased as the children became older. Parity of the mothers had a small effect on size at birth but age of the mother had no effect once parity was allowed for. Data on illnesses in the children were collected but no effect on growth could be detected. By far the most important determinant of growth which could be controlled is maternal smoking. About 40% of the women smoked, about 17% heavily (15 or more cigarettes per day) and the prevalence of smoking altered little during pregnancy. There was a graded effect of smoking on growth up to a 9% deficit in birth-weight, a 2% deficit in length at birth and a 1.5% deficit in head circumference in the babies born to the mothers who smoked most heavily (25 or more cigarettes per day) compared with non-smokers. There effects decreased with age but there were still residual effects at age five years.  相似文献   
1000.
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   
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