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   1279980篇
  免费   94758篇
  国内免费   1990篇
耳鼻咽喉   18211篇
儿科学   42365篇
妇产科学   37983篇
基础医学   187773篇
口腔科学   35491篇
临床医学   108753篇
内科学   252258篇
皮肤病学   26556篇
神经病学   99606篇
特种医学   50175篇
外国民族医学   366篇
外科学   198100篇
综合类   26651篇
现状与发展   1篇
一般理论   302篇
预防医学   93198篇
眼科学   29203篇
药学   98081篇
  1篇
中国医学   2643篇
肿瘤学   69011篇
  2018年   11893篇
  2015年   11677篇
  2014年   16086篇
  2013年   24498篇
  2012年   33751篇
  2011年   36169篇
  2010年   21327篇
  2009年   20124篇
  2008年   35150篇
  2007年   38158篇
  2006年   38720篇
  2005年   38033篇
  2004年   36581篇
  2003年   35578篇
  2002年   35112篇
  2001年   58270篇
  2000年   59762篇
  1999年   50877篇
  1998年   14308篇
  1997年   12871篇
  1996年   13128篇
  1995年   12425篇
  1994年   11806篇
  1993年   10939篇
  1992年   41116篇
  1991年   40477篇
  1990年   39996篇
  1989年   38816篇
  1988年   36209篇
  1987年   35453篇
  1986年   33815篇
  1985年   32217篇
  1984年   23993篇
  1983年   20872篇
  1982年   12413篇
  1981年   10973篇
  1980年   10250篇
  1979年   22682篇
  1978年   15941篇
  1977年   13769篇
  1976年   13007篇
  1975年   14223篇
  1974年   16702篇
  1973年   16103篇
  1972年   15361篇
  1971年   14263篇
  1970年   13243篇
  1969年   12752篇
  1968年   12004篇
  1967年   10502篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV‐hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau‐related models. Melatonin (10 μmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV‐hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase‐3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD.  相似文献   
63.
64.
65.
66.
67.
68.
69.
70.
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment.  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