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   2418588篇
  免费   197648篇
  国内免费   4404篇
耳鼻咽喉   34908篇
儿科学   73843篇
妇产科学   63711篇
基础医学   340124篇
口腔科学   68654篇
临床医学   220095篇
内科学   477268篇
皮肤病学   48806篇
神经病学   205335篇
特种医学   97293篇
外国民族医学   886篇
外科学   367694篇
综合类   56731篇
现状与发展   1篇
一般理论   1020篇
预防医学   194050篇
眼科学   56437篇
药学   180120篇
  7篇
中国医学   4405篇
肿瘤学   129252篇
  2018年   25225篇
  2017年   19536篇
  2016年   21430篇
  2015年   24235篇
  2014年   34868篇
  2013年   52799篇
  2012年   71800篇
  2011年   75597篇
  2010年   44288篇
  2009年   42553篇
  2008年   71780篇
  2007年   76229篇
  2006年   76993篇
  2005年   75055篇
  2004年   72255篇
  2003年   69823篇
  2002年   68890篇
  2001年   112820篇
  2000年   116855篇
  1999年   98764篇
  1998年   28393篇
  1997年   25980篇
  1996年   25828篇
  1995年   24980篇
  1994年   23494篇
  1993年   21835篇
  1992年   79638篇
  1991年   76602篇
  1990年   73773篇
  1989年   70996篇
  1988年   66045篇
  1987年   64957篇
  1986年   61487篇
  1985年   58558篇
  1984年   44416篇
  1983年   37847篇
  1982年   23161篇
  1981年   20559篇
  1980年   19231篇
  1979年   41374篇
  1978年   29095篇
  1977年   24450篇
  1976年   22892篇
  1975年   24004篇
  1974年   29690篇
  1973年   28097篇
  1972年   26252篇
  1971年   24172篇
  1970年   22770篇
  1969年   21110篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
This article describes the proceedings of the 2006 Annual Meeting of the Fetal Alcohol Spectrum Disorders Study Group (FASDSG), which was held in Baltimore, Maryland on June 24, 2006. The meeting was held in conjunction with the annual meeting of the Research Society on Alcoholism and was supported by a grant from the National Institute on Alcohol Abuse and Alcoholism. The 2005-2006 FASDSG officers, Daniel J. Bonthius (President), Heather Carmichael Olson (Vice-President), and Jennifer Thomas (Secretary-Treasurer), organized the meeting. Nationally prominent speakers delivered plenary lectures on topics of newborn screening, ethics, and neuroscience. Selected members of the FASDSG provided brief scientific data (FASt) reports, describing new research findings. Representatives from national agencies involved in fetal alcohol syndrome (FAS) research, treatment, and prevention provided updates regarding priorities, funding, and agency activities. Presentations were also made by the 2006 Student Merit Award recipient and by the 2006 Rosett Award recipient. The meeting served as a forum for clinicians, neuroscientists, psychologists, social scientists, and other professionals to discuss recent advances in FAS research and to identify the most important gaps in the understanding of alcohol-induced teratology.  相似文献   
95.
96.
Inter-individual variations in the development of silicosis, even within the same environments, have been reported, which suggest the contribution of genetic factors in silicosis aetiology. The aim of the present study was to determine whether there is any significant genetic influence on the development of silicosis. Furthermore, which genetic loci are responsible for the pulmonary response to silica exposure? Eight strains of inbred mice were used to examine the genetic influence on the lung fibrotic response to silica exposure. After intercross-breeding between the most susceptible and most resistant strains, a genome-wide linkage analysis of quantitative trait loci (QTL) was performed. Hydroxyproline was applied as an index, and genotypes of 167 marker genes were analysed by fragment analysis using a capillary-type sequencer. There was significant inter-strain difference in the mean concentration of hydroxyproline contents among the eight strains of mice. Breeding studies were conducted between the most susceptible, C57BL/6J, and the most resistant strain, CBA/J. A genome-wide linkage analysis of silica-exposed intercrossed cohorts identified significant QTL on chromosome 4 and suggestive QTL on chromosomes 3 and 18. The present study demonstrates that genetic factors may play a significant role in fibrotic-lung responses to silica; one significant and two suggestive quantitative trait loci were identified.  相似文献   
97.
AIMS: To establish all-cause and cause-specific death rates, and risk factors for mortality in insulin-treated diabetic individuals living in the province of Canterbury, New Zealand. METHODS: Insulin-treated diabetic subjects (n = 995) on the Canterbury Diabetes Registry were followed up over 15 years and vital status determined. Death rates were standardized and hazard regression was used to model the effects of demographic covariates on relative survival time. RESULTS: There were 419 deaths in 11 226.3 person-years of follow-up with a standardized mortality ratio (SMR) of 2.0 (95% confidence interval (CI) 1.8-2.2). Relative mortality was greatest for the group aged 0-29 years (SMR 3.0 (95% CI 2.4-3.7)). After controlling for diabetes duration and gender, a 10-year increment in age of onset was associated with a 33% decrease in relative hazard (95% CI 29-36%), indicating that excess mortality due to diabetes declines with rising age of onset. After controlling for age of onset and gender, each 10-year increment in duration of diabetes is associated with a 26% decrease in relative hazard (95% CI 24-29%), indicating that with longer survival the mortality hazard approaches the general population hazard. Relative mortalities were increased for cardiovascular, renal and respiratory disease, but not malignancy. Relative mortality from acute metabolic complications was increased in the subgroup with age of onset of diabetes < 30 years and requiring insulin within 1 year of diagnosis. CONCLUSIONS: Mortality rates are high for insulin-treated diabetic individuals relative to the general population.  相似文献   
98.
Social phobia, fear of negative evaluation and harm avoidance.   总被引:1,自引:0,他引:1  
This naturalistic, prospective investigation examined the role of fear of negative evaluation and the personality trait of harm avoidance in the anxiety levels of treated social phobia patients. One hundred and fifty-seven patients with DSM-IV social phobia were assessed before starting treatment and were then followed for up to two years. As expected, greater fear of negative evaluation and higher scores of harm avoidance were associated with greater anxiety at the 6 month follow-up, and harm avoidance remained a significant predictor at 24 months. However, no evidence was found for an interaction between the personality and cognitive variables examined. The findings are discussed in terms of the relative independence of these factors, as well as their potential implications for the treatment of this disorder.  相似文献   
99.
100.
OBJECTIVES: To evaluate changes in the mobility of the whole urethra, in the proximal urethra (funneling) and in the thickness of the urinary bladder wall, after a successful tension-free vaginal tape (TVT) procedure. METHODS: This prospective longitudinal study included 52 women with urodynamically confirmed stress urinary incontinence who had undergone a successful TVT procedure. Ultrasound examination was performed before the TVT procedure and at a median of 3 (range, 3-6) months after surgery. For all women, the changes to the urethra and urinary bladder induced by surgery were examined. For three mobility groups (low, intermediate and high urethral mobility before surgery) we compared the changes induced by the operation and the typical position and mobility of the tape. RESULTS: The position of the urethra at rest was not influenced by surgery. The operation significantly decreased the mobility of all parts of the urethra during Valsalva. The absolute changes of the vector of the urethral movement differed according to the mobility group (average decrease, 6 mm; decrease for women with low, intermediate and high mobility, respectively, 2-3 mm, 4-6 mm and 9 mm). The change in relative mobility was the same in all groups. The operation decreased funneling (width and depth) during maximal Valsalva. After surgery there was an increase in the thickness of the bladder wall (by 0.64 and 0.73 mm, respectively, at the anterior part and trigone). CONCLUSIONS: A successful TVT procedure did not influence the position of the urethra at rest but significantly decreased the mobility of the urethra during Valsalva and also decreased funneling at maximal Valsalva.  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