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   13055篇
  免费   1166篇
  国内免费   25篇
耳鼻咽喉   189篇
儿科学   524篇
妇产科学   373篇
基础医学   1616篇
口腔科学   115篇
临床医学   1475篇
内科学   2312篇
皮肤病学   253篇
神经病学   1518篇
特种医学   287篇
外科学   1460篇
综合类   80篇
一般理论   20篇
预防医学   1983篇
眼科学   321篇
药学   802篇
  1篇
中国医学   15篇
肿瘤学   902篇
  2024年   8篇
  2023年   287篇
  2022年   226篇
  2021年   855篇
  2020年   535篇
  2019年   789篇
  2018年   857篇
  2017年   570篇
  2016年   589篇
  2015年   569篇
  2014年   714篇
  2013年   866篇
  2012年   1255篇
  2011年   1223篇
  2010年   588篇
  2009年   478篇
  2008年   775篇
  2007年   710篇
  2006年   543篇
  2005年   497篇
  2004年   404篇
  2003年   326篇
  2002年   249篇
  2001年   34篇
  2000年   24篇
  1999年   22篇
  1998年   32篇
  1997年   21篇
  1996年   11篇
  1995年   20篇
  1994年   17篇
  1993年   18篇
  1992年   8篇
  1991年   9篇
  1990年   6篇
  1989年   7篇
  1988年   3篇
  1987年   3篇
  1985年   5篇
  1984年   6篇
  1983年   8篇
  1982年   13篇
  1981年   7篇
  1980年   8篇
  1979年   3篇
  1978年   6篇
  1976年   5篇
  1973年   3篇
  1972年   3篇
  1924年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
In this issue of the Hastings Center Report, James Sabin and his colleagues ask what responsibility investigators in a learning health organization have to patients when research—particularly research of which patients might be unaware—illuminates problematic aspects of the patients' care. Sabin and his colleagues were confronted by this question in the midst of designing a randomized controlled trial that sought to determine if an educational intervention targeted at patients with atrial fibrillation and their clinicians reduces underuse of oral anticoagulants. Worried about harm that might befall patients in the control group and fearing that they would be negligent bystanders if they knew these patients were at risk and did nothing, the investigators adopted a “workaround.” But the “workaround,” I suggest, was not a solution to the negligent bystander problem. Nor was it a solution to the problem as I would alternatively frame it—how to address instances of suboptimal patient care identified through research within learning health organizations.  相似文献   
52.
To determine percent of patients without malignancy and ≤ 40 years of age with high cumulative radiation doses through recurrent CT exams and assess imaging appropriateness. From the cohort of patients who received cumulative effective dose (CED) of ≥ 100 mSv over a 5-year period, a sub-set was identified with non-malignant disease. The top 50 clinical indications leading to multiple CTs were determined. Clinical decision support (CDS) system scores were analyzed using a widely adopted standard of 1–3 (red) as “not usually appropriate,” 4–6 (yellow) “may or may not be appropriate,” and 7–9 (green) “usually appropriate.” Clinicians reviewed patient records to assess compliance with appropriate use criteria (AUC). 9.6% of patients in our series were with non-malignant conditions and 1.4% with age ≤ 40 years. CDS scores (rounded) were 2% red, 38% yellow, 27% green, and 33% unscored CTs. Clinical society guidelines for CT exams, wherever available, were followed in 87.5 to 100% of cases. AUCs were not available for several clinical indications as also referral guidelines for serial CT imaging. More than half of CT exams were unrelated to follow-up of a primary chronic disease. We are faced with a situation wherein patients in age ≤ 40 years require or are thought to require many CT exams over the course of a few years but the radiation risk creates concern. There is a fair number of conditions for which AUC are not available. Suggested solutions include development of CT scanners with lesser radiation dose and further development of appropriateness criteria.  相似文献   
53.
54.
55.
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2.  相似文献   
56.
57.
58.
59.
Lessons Learned
  • The combination of trametinib and sorafenib has an acceptable safety profile, albeit at doses lower than approved for monotherapy.
  • Maximum tolerated dose is trametinib 1.5 mg daily and sorafenib 200 mg twice daily.
  • The limited anticancer activity observed in this unselected patient population does not support further exploration of trametinib plus sorafenib in patients with hepatocellular carcinoma.
BackgroundThe RAS/RAF/MEK/ERK signaling pathway is associated with proliferation and progression of hepatocellular carcinoma (HCC). Preclinical data suggest that paradoxical activation of the MAPK pathway may be one of the resistance mechanisms of sorafenib; therefore, we evaluated trametinib plus sorafenib in HCC.MethodsThis was a phase I study with a 3+3 design in patients with treatment‐naïve advanced HCC. The primary objective was safety and tolerability. The secondary objective was clinical efficacy.ResultsA total of 17 patients were treated with three different doses of trametinib and sorafenib. Two patients experienced dose‐limiting toxicity, including grade 4 hypertension and grade 3 elevation of aspartate aminotransferase (AST)/alanine aminotransferase (ALT)/bilirubin over 7 days. Maximum tolerated dose was trametinib 1.5 mg daily and sorafenib 200 mg twice a day. The most common grade 3/4 treatment‐related adverse events were elevated AST (37%) and hypertension (24%). Among 11 evaluable patients, 7 (63.6%) had stable disease with no objective response. The median progression‐free survival (PFS) and overall survival (OS) were 3.7 and 7.8 months, respectively. Phosphorylated‐ERK was evaluated as a pharmacodynamic marker, and sorafenib plus trametinib inhibited phosphorylated‐ERK up to 98.1% (median: 81.2%) in peripheral blood mononuclear cells.ConclusionTrametinib and sorafenib can be safely administered up to trametinib 1.5 mg daily and sorafenib 200 mg twice a day with limited anticancer activity in advanced HCC.  相似文献   
60.
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