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   28759篇
  免费   3274篇
  国内免费   540篇
耳鼻咽喉   303篇
儿科学   463篇
妇产科学   353篇
基础医学   1416篇
口腔科学   9532篇
临床医学   2655篇
内科学   2304篇
皮肤病学   524篇
神经病学   469篇
特种医学   434篇
外国民族医学   1篇
外科学   1206篇
综合类   3154篇
现状与发展   3篇
预防医学   2661篇
眼科学   70篇
药学   4252篇
  30篇
中国医学   1319篇
肿瘤学   1424篇
  2024年   31篇
  2023年   528篇
  2022年   528篇
  2021年   1009篇
  2020年   1289篇
  2019年   1289篇
  2018年   1198篇
  2017年   1171篇
  2016年   1213篇
  2015年   1158篇
  2014年   1732篇
  2013年   2476篇
  2012年   1693篇
  2011年   1769篇
  2010年   1373篇
  2009年   1221篇
  2008年   1276篇
  2007年   1252篇
  2006年   1121篇
  2005年   1064篇
  2004年   907篇
  2003年   841篇
  2002年   721篇
  2001年   638篇
  2000年   523篇
  1999年   450篇
  1998年   366篇
  1997年   407篇
  1996年   312篇
  1995年   356篇
  1994年   288篇
  1993年   213篇
  1992年   227篇
  1991年   193篇
  1990年   176篇
  1989年   198篇
  1988年   158篇
  1987年   148篇
  1986年   125篇
  1985年   140篇
  1984年   110篇
  1983年   86篇
  1982年   91篇
  1981年   86篇
  1980年   72篇
  1979年   47篇
  1978年   54篇
  1977年   81篇
  1976年   53篇
  1975年   37篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
3.
4.
5.
Oral cancer, with an around 50% mortality rate, is one of the most common malignancies world-wide. It is often detected in advanced or terminal stage and has a poor prognosis, although substantial progress in cancer management. Microbiome has become an increasingly recognized factor that may contribute to the cancerous development. Oral microbiological population comprising more than 700 bacterial species, varies since saliva and different habitats of oral cavity. A shift of composition of oral microbiome from usual condition to functional inflammation to pathological state has been discovered amongst patients with premalignant disorders and oral carcinoma, with evidence suggesting the tumor microenvironment (TME) could strongly exacerbate the influence of oral microorganisms. The complex interactions taking place in either cancer formation or progression have been evaluated in several publications, however given their results’ heterogeneity, a review is needed to correctly untangle the potential correlation in this group of pro-carcinogenesis. In this review, we briefly summarize our current knowledge of the role of oral microbiome, focusing on its potential crosstalk with TME in oral squamous cell carcinomas (OSCC) more precisely, and pave the way for manipulating oral microbiome to deal with OSCC in the future.  相似文献   
6.
7.
The fractional uptake of ingested aluminium and aluminium compounds (aluminium citrate, aluminium nitrate, aluminium chloride, aluminium sulphate, aluminium hydroxide, aluminium oxide, aluminium metal, powdered aluminium pot electrolyte, acidic sodium aluminium phosphate (SALP), basic sodium aluminium phosphate (Kasal), sodium aluminium silicate and FD&C red 40 aluminium lake) from the gastro-intestinal tract of adult female rats was measured. This was determined by comparing retained body burden of 26Al at seven days post-admistration of an i.v. injection of 26Al-labelled aluminium citrate with that retained following the gastric admistration of 26Al-labelled test compounds as either solutions or suspended solid. The calculated percentage uptake of 26Al for all the aluminium solutions was similar: aluminium citrate 0.08%, aluminium chloride 0.05%, aluminium nitrate 0.05% and aluminium sulphate 0.21%. The uptake of 26Al administered as insoluble particulates was lower: 0.03% for aluminium hydroxide; 0.02% for aluminium oxide; 0.04% for powdered pot electrolyte; 0.12% for sodium aluminium silicate; and 0.09% for FD&C red 40 aluminium lake. For aluminium metal, SALP and Kasal the amount of 26Al present in the rats was insufficient to determine uptake and was less than 0.03%. The results produced for aluminium citrate, aluminium hydroxide and aluminium sulphate are close to those published for man.  相似文献   
8.
9.
The aim of this study was to analyse the effect of body mass index (BMI), both low and high values, on the perioperative complication rate in patients with oral squamous cell carcinoma (OSCC). The medical records of 259 patients operated between 2014 and 2017 for OSCC were reviewed. Univariate and multivariate analyses were performed. Sixty of the 259 patients developed 87 complications. Low or high BMI was not associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade. Low BMI, American Society of Anesthesiologists score 2 and 3, a longer operating time, and increased blood loss were associated with a longer hospital stay. Low BMI was associated with a longer hospital stay. Neither low nor high BMI was associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade.  相似文献   
10.
The contemporary literature is discordant regarding the role of delayed diagnosis in the prognosis of patients with oral cancer. This study examined data on a previously reported cohort of 101 patients with oral squamous cell carcinoma diagnosed at a single institution between 2008 and 2010. The time interval between symptom onset and initial histological diagnosis (diagnostic delay) was recorded for each patient, as were demographic data and cancer features such as T stage, nodal status, and smoking status. The mean follow-up period was 4 years 10 months. The mean diagnostic delay was 4 months, mean overall survival was 5 years 6 months, and mean disease-specific survival was 4 years 9 months. No significant correlation was found between diagnostic delay and overall survival, disease-specific survival, or recurrence rates. Patients with node-positive disease were more likely to be diagnosed earlier, whereas women and non-smokers were more likely to have a delayed diagnosis. Inherent tumour biology is likely an important prognostic factor separate to diagnostic delay. Public education efforts should focus on symptom recognition and encourage early presentation for investigation of oral lesions, particularly for females and non-smokers, so that more aggressive tumours can be treated sooner to give the best chance at survival.  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