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   2336篇
  免费   226篇
  国内免费   4篇
耳鼻咽喉   24篇
儿科学   113篇
妇产科学   63篇
基础医学   289篇
口腔科学   93篇
临床医学   279篇
内科学   586篇
皮肤病学   32篇
神经病学   199篇
特种医学   68篇
外科学   234篇
综合类   61篇
一般理论   2篇
预防医学   286篇
眼科学   34篇
药学   94篇
中国医学   2篇
肿瘤学   107篇
  2021年   48篇
  2020年   25篇
  2019年   36篇
  2018年   41篇
  2017年   33篇
  2016年   27篇
  2015年   51篇
  2014年   54篇
  2013年   82篇
  2012年   113篇
  2011年   105篇
  2010年   53篇
  2009年   55篇
  2008年   90篇
  2007年   102篇
  2006年   106篇
  2005年   125篇
  2004年   96篇
  2003年   90篇
  2002年   86篇
  2001年   81篇
  2000年   91篇
  1999年   69篇
  1998年   33篇
  1996年   22篇
  1995年   17篇
  1994年   27篇
  1993年   20篇
  1992年   45篇
  1991年   47篇
  1990年   50篇
  1989年   47篇
  1988年   41篇
  1987年   53篇
  1986年   49篇
  1985年   41篇
  1984年   29篇
  1983年   22篇
  1982年   14篇
  1981年   17篇
  1979年   25篇
  1978年   17篇
  1976年   18篇
  1974年   23篇
  1972年   18篇
  1971年   17篇
  1970年   21篇
  1969年   15篇
  1967年   17篇
  1966年   14篇
排序方式: 共有2566条查询结果,搜索用时 31 毫秒
1.
The patellar ligament (PL) is an epiphyseal ligament and is part of the extensor complex of the knee. The ligament has gained attention due to its clinical relevance to autograft and tendinopathy. A variety of anatomical variations of the PL such as aplasia, numerical variations, and vascularity are being reported recently by clinicians and anatomists. The aim of this literature was to review the available literature to provide a consensus regarding anatomic variations of the PL, neurovasculature surrounding the PL, histology of the PL, and various aspects of PL measurements with relevance to the surgical considerations and sex and age-related differences. A narrative review of the patellar ligament was performed by conducting a detailed literature search and review of relevant articles. A total of 90 articles on the patellar ligament were included and were categorized into studies based on anatomical variations, neurovasculature, morphometrics, microanatomy, sex and age-related difference, and ACL reconstruction. The anatomical variations and morphometrics of the PL were found to correlate with the frequency of strain injuries, tendinopathy, and efficacy of the PL autograft in anterior cruciate ligament reconstruction. The sex differences in PL measurements and the effect of estrogen on collagen synthesis explained a higher incidence of patellar tendinopathy in women. An awareness of its variations enables careful selection of surgical incisions, thereby avoiding complications related to nerve injury. Accurate knowledge of the PL microanatomy assists in understanding the mechanism of ligament degeneration, rupture, autograft harvesting, and ligamentization results.  相似文献   
2.
3.
Bommersbach  Tanner  Dube  Lisa  Li  Luming 《The Psychiatric quarterly》2021,92(3):1079-1092
Psychiatric Quarterly - While COVID-19 has had widespread impact on the way behavioral health services are delivered, very little research exists characterizing how providers have perceived these...  相似文献   
4.
5.
6.
7.
ObjectiveSentinel lymph node (SLN) biopsy represents an evolution in the advancement of minimally invasive surgical techniques for gynecologic cancers. Prospective and retrospective studies have consistently shown its accuracy in the detection of lymph node metastases for endometrial and cervical cancers. However, consistent with any emerging surgical technique in the early phases of adoption, new questions have arisen regarding its application and impact. This paper served as a scoping review to identify the key controversies that have arisen in the field of SLN biopsy for endometrial and cervical cancers.Data SourcesSeveral key controversies were identified, and PubMed, the Cochrane Library (cochranelibrary.com) advanced search function, and the National Comprehensive Cancer Network guidelines were searched for supporting evidence. These included search terms such as “the accuracy of SLN biopsy for high grade endometrial cancer or cervical cancers >2-cm,” “cost effectiveness of SLN biopsy for gynecologic cancers,” “clinical significance of low volume metastases in endometrial cancer,” “morbidity of SLN biopsy for endometrial and cervical cancer,” and “impact on cancer survival of SLN biopsy for endometrial and cervical cancer.”Methods of Study SelectionStudies were selected for review if they included significant numbers of patients, were level I evidence, or were prospective trials. Where this level of evidence failed to exist, seminal observational series that were published in high-quality journals were included.Tabulation, Integration, and ResultsSimilar studies were listed and subcategorized and cross-compared, excluding those that included repeated analyses of the same patient populations. The relevant clinical trials or observational studies were clustered and reviewed for each chosen controversy. Adequate evidence supports the accuracy of SLN biopsy in the staging of high-grade endometrial cancer and cervical cancer, and it seems to be a cost-effective strategy for invasive endometrial cancer. Conclusive evidence was lacking with respect to the oncologic outcomes related to SLN biopsy, the impact on patient morbidity, and whether clinicians should treat isolated tumor cells in SLNs with adjuvant therapy.ConclusionSLN biopsy is an accepted staging strategy for cervical and endometrial cancer surgery; however, controversies remain in how it can be applied with the most safety and efficacy. These ultimately need to be resolved with further clinical trials and observations of larger series of patients.  相似文献   
8.
Journal of Thrombosis and Thrombolysis - Recent trials suggest that aspirin for primary prevention may do more harm than good for some, including adults over 70 years of age. We sought to...  相似文献   
9.
Caufield et al. (1) have suggested that the acquisition of mutans streptococci in young children most likely takes place during a "window of infectivity" from 19 to 31 months of age. OBJECTIVES AND METHODS: This study determined the prevalence of dental caries and bacterial infection in a randomly selected sample of 199 children 6 to 36 months old from the island of Saipan in the Common-wealth of the Northern Mariana Islands, USA. The relationships between caries and Streptococcus mutans infection, hypoplasia, diet and oral hygiene behavior were investigated. RESULTS AND CONCLUSIONS: The overall estimated prevalence of caries was high: 46.8% of the children had white spot lesions and 39.1% had enamel cavitation. Colonization was seen in very young children; S. mutans was detected in 25% of the predentate children. The results of multi-variable modeling support the hypothesis that bacterial infection, diet, and hypoplasia are important in the etiology of dental caries in this population. Adjusted for age and ethnicity, children with a high level of S. mutans detected were 5 times more likely to have dental caries than children with a lower level of S. mutans detected. Hypoplasia and a high cariogenicity score (diet) were also significant independent predictors. The odds of having any white spot lesions or enamel cavitation were 9.6 times greater for children with any hypoplasia, and 7.8 times greater for children with high cariogenicity scores relative to those with lower scores after adjusting for level of S. mutans, age and ethnicity. Sleeping with a bottle, maternal sharing of utensils, and high snacking frequency were not significant predictors of caries in this population.  相似文献   
10.
BACKGROUND: Periodontal diseases affect over half the adults in the U.S., disproportionately affecting minority populations. Periodontitis can be treated in early stages, but it is not clear what features indicate, or could be risk factors for, early stages of periodontal attachment loss. This study aimed to evaluate associations between clinical and other risk indicators of early periodontitis. METHODS: A cross-sectional evaluation of 225 healthy and early periodontitis adults aged 20 to 40 years was performed. Clinical measurements, demographic information, and smoking histories were recorded. Analyses evaluated demographic and clinical associations with health and early periodontitis disease categories and periodontal attachment loss. Patterns of attachment loss at interproximal and buccal/lingual sites were evaluated. RESULTS: Subject age, plaque, and measures of gingivitis exhibited associations with attachment loss and probing depth. More periodontal attachment loss was detected in African-American and Hispanic subjects compared to Asian and Caucasian subjects. Smoking history was associated with attachment loss. At interproximal sites, lower molars most frequently had attachment loss, whereas at buccal/lingual sites, higher proportions of lower bicuspid teeth demonstrated attachment loss compared with other sites. CONCLUSIONS: In this study of subjects with minimal attachment loss, gingival inflammation was associated with early periodontitis. Lower molar interproximal sites were frequently associated with interproximal attachment loss, whereas lower bicuspid teeth were at risk for gingival recession on buccal surfaces.  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