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   163063篇
  免费   33190篇
  国内免费   2635篇
耳鼻咽喉   5464篇
儿科学   5517篇
妇产科学   2555篇
基础医学   5637篇
口腔科学   1695篇
临床医学   27755篇
内科学   49909篇
皮肤病学   7790篇
神经病学   15575篇
特种医学   7324篇
外科学   42595篇
综合类   264篇
现状与发展   72篇
一般理论   4篇
预防医学   7370篇
眼科学   3714篇
药学   2450篇
中国医学   200篇
肿瘤学   12998篇
  2024年   513篇
  2023年   4835篇
  2022年   1207篇
  2021年   3634篇
  2020年   6281篇
  2019年   2544篇
  2018年   7832篇
  2017年   7703篇
  2016年   8933篇
  2015年   9178篇
  2014年   16351篇
  2013年   16560篇
  2012年   6944篇
  2011年   6849篇
  2010年   11159篇
  2009年   14859篇
  2008年   6639篇
  2007年   4863篇
  2006年   7207篇
  2005年   4409篇
  2004年   3470篇
  2003年   2398篇
  2002年   2411篇
  2001年   4001篇
  2000年   3210篇
  1999年   3376篇
  1998年   3692篇
  1997年   3500篇
  1996年   3383篇
  1995年   3225篇
  1994年   1960篇
  1993年   1593篇
  1992年   1387篇
  1991年   1432篇
  1990年   1077篇
  1989年   1191篇
  1988年   1026篇
  1987年   856篇
  1986年   897篇
  1985年   726篇
  1984年   548篇
  1983年   521篇
  1982年   515篇
  1981年   398篇
  1980年   361篇
  1979年   313篇
  1978年   334篇
  1977年   400篇
  1975年   280篇
  1972年   279篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.
66.
67.
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
68.
BACKGROUND Helicobacter pylori(H.pylori)infection is known to prevent the occurrence of gastroesophageal reflux disease(GERD)by inducing gastric mucosal atrophy.However,little is known about the relationship between atrophic gastritis(AG)and GERD.AIM To confirm the inverse correlation between AG and the occurrence and severity of GERD.METHODS Individuals receiving health checkups who underwent upper gastrointestinal endoscopy at Seoul National University Healthcare System Gangnam Center were included.The grade of reflux esophagitis was evaluated according to the Los Angeles classification.Endoscopic AG(EAG)was categorized into six grades.Serologic AG(SAG)was defined as pepsinogen I≤70 ng/m L and pepsinogen I/II ratio≤3.0.The association between the extent of EAG and SAG and the occurrence and severity of GERD was evaluated using multivariate logistic regression analysis.RESULTS In total,4684 individuals with GERD were compared with 21901 healthy controls.In multivariate logistic regression analysis,advanced age,male sex,body mass index>23 kg/m2,presence of metabolic syndrome,current smoking,and alcohol consumption were associated with an increased risk of GERD.Seropositivity for H.pylori immunoglobulin G antibodies was associated with a decreased risk of GERD.There was an inverse correlation between the extent of EAG and occurrence of GERD:Odds ratio(OR),1.01[95%confidence interval(CI):0.90-1.14]in C1,0.87(0.78-0.97)in C2,0.71(0.62-0.80)in C3,0.52(0.44-0.61)in O1,0.37(0.29-0.48)in O2,and 0.28(0.18-0.43)in O3.Additionally,the extent of EAG showed an inverse correlation with the severity of GERD.The presence of SAG was correlated with a reduced risk of GERD(OR=0.49,95%CI:0.28-0.87,P=0.014).CONCLUSION The extent of EAG and SAG exhibited strong inverse relationships with the occurrence and severity of GERD.AG followed by H.pylori infection may be independently protect against GERD.  相似文献   
69.
The term “oligometastatic prostate cancer” refers to a heterogeneous group of disease states currently defined solely on the basis of clinical features. Oligorecurrent disease, de novo oligometastases, and oligoprogressive disease likely have unique biologic underpinnings and natural histories. Evidence suggesting the existence of a subset of patients who harbor prostate cancer with limited metastatic potential currently includes disparate and overwhelmingly retrospective reports. Nevertheless, emerging prospective data have corroborated the “better-than-expected,” retrospectively observed outcomes, particularly in the setting of oligorecurrent prostate cancer. Improved functional imaging with prostate-specific membrane antigen-targeted strategies may enhance the identification of patients with oligometastatic prostate cancer in the short term. In the long term, refinement of the oligometastatic case definition likely will require biologic risk-stratification schemes. To determine optimal treatment strategies and identify patients most likely to benefit from metastasis-directed therapy, future efforts should focus on conducting high-quality, prospective trials with much-needed molecular correlative studies.  相似文献   
70.
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