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   1808篇
  免费   121篇
  国内免费   11篇
耳鼻咽喉   3篇
儿科学   93篇
妇产科学   14篇
基础医学   198篇
口腔科学   36篇
临床医学   183篇
内科学   483篇
皮肤病学   23篇
神经病学   80篇
特种医学   330篇
外科学   173篇
综合类   55篇
预防医学   82篇
眼科学   10篇
药学   95篇
肿瘤学   82篇
  2022年   9篇
  2021年   26篇
  2020年   10篇
  2019年   21篇
  2018年   23篇
  2017年   13篇
  2016年   19篇
  2015年   25篇
  2014年   39篇
  2013年   50篇
  2012年   61篇
  2011年   50篇
  2010年   54篇
  2009年   40篇
  2008年   50篇
  2007年   57篇
  2006年   54篇
  2005年   51篇
  2004年   53篇
  2003年   45篇
  2002年   39篇
  2001年   38篇
  2000年   48篇
  1999年   55篇
  1998年   107篇
  1997年   81篇
  1996年   82篇
  1995年   60篇
  1994年   62篇
  1993年   67篇
  1992年   17篇
  1991年   24篇
  1990年   21篇
  1989年   55篇
  1988年   35篇
  1987年   45篇
  1986年   30篇
  1985年   39篇
  1984年   27篇
  1983年   22篇
  1982年   25篇
  1981年   29篇
  1980年   30篇
  1979年   12篇
  1978年   20篇
  1977年   23篇
  1976年   24篇
  1975年   15篇
  1973年   7篇
  1969年   6篇
排序方式: 共有1940条查询结果,搜索用时 31 毫秒
31.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
32.
Emotional eating is associated with an increased risk of binge eating, eating in the absence of hunger and obesity risk. While previous studies with children and adolescents suggest that emotion regulation may be a key predictor of this dysregulated eating behavior, little is known about what other factors may be influencing the link between emotional regulation and emotional eating in adolescence. This multi-method longitudinal study (n = 138) utilized linear regression models to examine associations between childhood emotion regulation, adolescent weight status and negative body image, and emotional eating at age 17. Emotion regulation predicted adolescent emotional eating and this link was moderated by weight status (β = 1.19, p < 0.01) and negative body image (β = −0.34, p < 0.01). Higher engagement in emotional eating was predicted by lower emotional regulation scores among normal-weight teens (β = −0.46, p < 0.001) but not among overweight/obese teens (β = 0.32, p > 0.10). Higher scores on emotion regulation were significantly associated with lower emotional eating at high (β = −1.59, p < 0.001) and low (β = −1.00, p < 0.01) levels of negative body image. Engagement in emotional eating was predicted by higher negative body image among overweight/obese teens only (β = 0.70, p < 0.001). Our findings show that while better childhood emotion regulation skills are associated with lower emotional eating, weight status and negative body image influence this link and should be considered as important foci in future interventions that aim to reduce emotional eating in adolescence.  相似文献   
33.
Cutaneous infections occurring in abattoir workers are an under-recognizedcause of occupational morbidity. This study examined the incidentrates of cutaneous infection in a medium sized metropolitanabattoir in Adelaide, South Australia. The results show thatcutaneous infections are common (0.65 per 1,000 working days)and that there exists an association between the nature of thework task within the abattoir and infection rates. Specifically,those individuals handling animal hides have higher rates ofinfection compared to other workers. The implications of thesefindings are discussed with particular emphasis on the preventionof these infections.  相似文献   
34.
In this first multi-centre study in Scotland, 1028 consecutive Gram-negative and staphylococci strains were obtained from four major teaching hospitals. E. coli was the most common organism among both intensive care units (ICUs) (39%) and non-ICU strains (46.6%). The prevalence of antibiotic resistance among E. coli was always higher in isolates from ICUs than non-ICUs: ceftazidime (14.1%, 7.2%), ceftriaxone (12.7%, 6.1%), cefotaxime (15.5%, 8.7%), cefuroxime (28.8%, 20.8%), amoxicillin plus clavulanic acid (52.2%, 38.8%) and gentamicin (7.0%, 2.8%). The highest incidences of resistance were identified among Enterobacter/Citrobacter spp. from ICUs; 43.8%, 41.7%, 45.8%, 54.2%, 87.5% and 10.4% of these organisms were resistant to ceftazidime, ceftriaxone, cefotaxime, cefuroxime, amoxicillin plus clavulanic acid and gentamicin, respectively.  相似文献   
35.
Coronal sections of the distal radioulnar joint (DRUJ) were studied in 13 preserved cadaveric wrists specimens before and after 2 mm of shortening of the ulna. The DRUJs were subclassified on the basis of the DRUJ angle and depth of the sigmoid notch. The changes in extent and location of area of contact and radioulnar separation were noted. Although reduction in area of contact occurred in every specimen and DRUJ type, the maximum radioulnar separation and reduction in area of contact occurred in the DRUJ type IB and IIB. This could be a possible factor producing point loading and subsequent occurrence of DRUJ remodelling in the long-term after shortening of the ulna.  相似文献   
36.
37.
Hypospadias trends in two US surveillance systems   总被引:6,自引:0,他引:6  
OBJECTIVE: Hypospadias is a common congenital anomaly, the cause of which is unknown. Unexplained increases in the rates of hypospadias occurred in five European countries in the 1970s and 1980s. We examined data from two birth defects surveillance systems in the United States for evidence of similar trends. METHODOLOGY: The Metropolitan Atlanta Congenital Defects Program (MACDP) provided birth prevalence rates from 1968 to 1993. The nationwide Birth Defects Monitoring Program (BDMP) provided rates from 1970 to 1993. MACDP data are population-based and could be categorized by the severity of the hypospadias. BDMP data allowed analysis of rate trends for the four census regions of the United States. RESULTS: Data from both surveillance systems showed an approximate doubling of hypospadias rates in the 1970s and 1980s. MACDP data showed that the rate of severe cases increased while the ratio of mild to severe cases decreased. BDMP data showed that hypospadias rates increased markedly in all four regions of the United States. CONCLUSIONS: The observed increases are unlikely to be attributable to increased sensitivity of the surveillance systems or the identification of more mild cases by physicians over time, because either trend would have increased rather than decreased the ratio of mild to severe cases. If real, these trends represent the largest number of cases and the first report of an increase in hypospadias rates outside of Europe. Additional investigation of a possible increase in hypospadias rates is warranted.  相似文献   
38.
39.
Mutations in the transforming growth factor beta type II receptor (TGFbetaRII) gene have been detected in several human cancer types exhibiting microsatellite instability. Using intron primers previously reported for examination of the entire coding region of the TGFbetaRII gene, 29 sporadic gastric cancers were screened with non-radioactive single strand conformation polymorphism and subsequent DNA sequencing analysis. Mutations of the TGFbetaRII gene were detected in three out of 29 tumors (10%). Two cases showed deletions in a polyadenine tract in both alleles and was positively associated with replication error. One case had an insertion of GA dinucleotide sequence in one allele. Mutations of the TGFbetaRII gene were restricted to exon 3 and other coding regions were not affected. Loss of heterozygosity was detected by analyzing a polymorphic site in intron 2. Three out of nine (33%) informative cases, which were all of intestinal type and advanced cases, showed loss of heterozygosity but neither TGFbetaRII mutation nor replication error was found in these cases. Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different extent in the gastric cancer with genetically abnormal transforming growth factor. Although the numbers studied are small, homozygous (A)10 deletion or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and progression of at least some part of sporadic gastric cancer.   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