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   27277篇
  免费   1854篇
  国内免费   373篇
耳鼻咽喉   412篇
儿科学   469篇
妇产科学   595篇
基础医学   3884篇
口腔科学   705篇
临床医学   2416篇
内科学   5198篇
皮肤病学   600篇
神经病学   1977篇
特种医学   1882篇
外科学   4331篇
综合类   298篇
一般理论   10篇
预防医学   1086篇
眼科学   666篇
药学   2420篇
  2篇
中国医学   269篇
肿瘤学   2284篇
  2023年   133篇
  2022年   90篇
  2021年   540篇
  2020年   390篇
  2019年   660篇
  2018年   726篇
  2017年   596篇
  2016年   690篇
  2015年   1022篇
  2014年   1266篇
  2013年   1452篇
  2012年   2137篇
  2011年   2101篇
  2010年   1317篇
  2009年   1222篇
  2008年   1641篇
  2007年   1657篇
  2006年   1462篇
  2005年   1397篇
  2004年   1244篇
  2003年   1080篇
  2002年   964篇
  2001年   786篇
  2000年   764篇
  1999年   609篇
  1998年   276篇
  1997年   251篇
  1996年   229篇
  1995年   207篇
  1994年   165篇
  1993年   152篇
  1992年   250篇
  1991年   200篇
  1990年   187篇
  1989年   215篇
  1988年   174篇
  1987年   134篇
  1986年   120篇
  1985年   92篇
  1984年   97篇
  1983年   61篇
  1982年   79篇
  1981年   58篇
  1980年   57篇
  1979年   62篇
  1978年   48篇
  1977年   61篇
  1976年   62篇
  1975年   47篇
  1972年   44篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
7.
Benign breast disease (BBD) is an established breast cancer (BC) risk factor, but it is unclear whether the magnitude of the association applies to women at familial or genetic risk. This information is needed to improve BC risk assessment in clinical settings. Using the Prospective Family Study Cohort, we used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of BBD with BC risk. We also examined whether the association with BBD differed by underlying familial risk profile (FRP), calculated using absolute risk estimates from the Breast Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) model. During 176,756 person-years of follow-up (median: 10.9 years, maximum: 23.7) of 17,154 women unaffected with BC at baseline, we observed 968 incident cases of BC. A total of 4,704 (27%) women reported a history of BBD diagnosis at baseline. A history of BBD was associated with a greater risk of BC: HR = 1.31 (95% CI: 1.14–1.50), and did not differ by underlying FRP, with HRs of 1.35 (95% CI: 1.11–1.65), 1.26 (95% CI: 1.00–1.60), and 1.40 (95% CI: 1.01–1.93), for categories of full-lifetime BOADICEA score <20%, 20 to <35%, ≥35%, respectively. There was no difference in the association for women with BRCA1 mutations (HR: 1.64; 95% CI: 1.04–2.58), women with BRCA2 mutations (HR: 1.34; 95% CI: 0.78–2.3) or for women without a known BRCA1 or BRCA2 mutation (HR: 1.31; 95% CI: 1.13–1.53) (pinteraction = 0.95). Women with a history of BBD have an increased risk of BC that is independent of, and multiplies, their underlying familial and genetic risk.  相似文献   
8.
PurposeTo determine the prognostic effect of upper tract urothelial carcinoma (UTUC) with variant histology (VH) after radical nephroureterectomy (RNU).Patients and MethodsThe data of 1173 patients who received RNU for UTUC without neoadjuvant chemotherapy in 11 institutions between 2002 and 2016 were retrospectively reviewed. A matched propensity score analysis was performed. Clinicopathologic variables, recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were compared between patients with pure UTUC and patients with UTUC and VH. Univariate and multivariate Cox proportional regression models were used to determine the independent variables associated with oncologic outcomes.ResultsUTUC with VH was observed in 93 patients (7.9%). After propensity score matching, UTUC with VH showed no difference in clinicopathologic features compared to pure UTUC; however, it was associated with shorter RFS, CSS, and OS (log rank, P = .011, P = .002, P = .006, respectively). Additionally, the multivariate analysis revealed that VH was independently associated with a poor RFS [hazard ratio (HR) = 1.92; 95% confidence interval (CI), 1.27-2.89; P = .002], CSS (HR = 4.47; 95% CI, 1.99-10.1; P = .001), and OS (HR = 3.00; 95% CI, 1.55-5.78; P = .001). However, the Kaplan-Meier method revealed that differences in RFS, CSS, and OS were not significant in patients who received adjuvant chemotherapy (log rank, P = .562, P = .060, P = .153, respectively).ConclusionUTUC with VH was independently associated with poor oncologic outcomes in patients with UTUC after RNU. Although patients with UTUC and VH had a poor prognosis compared to patients with pure UTUC, adjuvant chemotherapy would be helpful in improving the survival rates of these patients.  相似文献   
9.
10.
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