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   3760453篇
  免费   322358篇
  国内免费   14079篇
耳鼻咽喉   52250篇
儿科学   119723篇
妇产科学   96633篇
基础医学   593462篇
口腔科学   103187篇
临床医学   342380篇
内科学   669210篇
皮肤病学   96211篇
神经病学   318875篇
特种医学   150254篇
外国民族医学   354篇
外科学   582295篇
综合类   111501篇
现状与发展   24篇
一般理论   2351篇
预防医学   318713篇
眼科学   87281篇
药学   261993篇
  21篇
中国医学   10238篇
肿瘤学   179934篇
  2021年   55355篇
  2020年   35289篇
  2019年   58373篇
  2018年   72242篇
  2017年   54702篇
  2016年   60456篇
  2015年   74365篇
  2014年   108827篇
  2013年   173997篇
  2012年   99975篇
  2011年   102170篇
  2010年   119553篇
  2009年   122925篇
  2008年   89271篇
  2007年   93827篇
  2006年   103677篇
  2005年   99163篇
  2004年   101019篇
  2003年   91809篇
  2002年   81205篇
  2001年   127663篇
  2000年   122015篇
  1999年   116021篇
  1998年   68083篇
  1997年   64985篇
  1996年   63294篇
  1995年   58940篇
  1994年   52918篇
  1993年   49391篇
  1992年   84062篇
  1991年   81535篇
  1990年   78020篇
  1989年   76348篇
  1988年   70614篇
  1987年   69191篇
  1986年   65507篇
  1985年   65180篇
  1984年   56859篇
  1983年   51101篇
  1982年   44630篇
  1981年   41841篇
  1980年   39431篇
  1979年   48416篇
  1978年   41004篇
  1977年   36722篇
  1976年   34072篇
  1975年   33657篇
  1974年   35917篇
  1973年   34299篇
  1972年   32317篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
261.
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers  相似文献   
262.
263.
264.
265.
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST.  相似文献   
266.
267.
268.
269.
Pharmaceutical Chemistry Journal - Three extracts were produced from the above-ground part of the meadowsweet Filipendula ulmaria (L.) Maxim. using water, 40% ethanol, and 70% ethanol. Comparative...  相似文献   
270.
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