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   2436866篇
  免费   196675篇
  国内免费   8202篇
耳鼻咽喉   32081篇
儿科学   80122篇
妇产科学   68215篇
基础医学   339776篇
口腔科学   66738篇
临床医学   221120篇
内科学   490681篇
皮肤病学   57881篇
神经病学   202270篇
特种医学   96027篇
外国民族医学   708篇
外科学   370068篇
综合类   58126篇
现状与发展   4篇
一般理论   830篇
预防医学   195483篇
眼科学   54015篇
药学   171299篇
  55篇
中国医学   5018篇
肿瘤学   131226篇
  2018年   26501篇
  2017年   20516篇
  2016年   23865篇
  2015年   26692篇
  2014年   37612篇
  2013年   56246篇
  2012年   72474篇
  2011年   77645篇
  2010年   47071篇
  2009年   45378篇
  2008年   72054篇
  2007年   76431篇
  2006年   77714篇
  2005年   75388篇
  2004年   72036篇
  2003年   69245篇
  2002年   66341篇
  2001年   118656篇
  2000年   121669篇
  1999年   101313篇
  1998年   29866篇
  1997年   26890篇
  1996年   27641篇
  1995年   27037篇
  1994年   24875篇
  1993年   23399篇
  1992年   80290篇
  1991年   77516篇
  1990年   74422篇
  1989年   70918篇
  1988年   65489篇
  1987年   64146篇
  1986年   60288篇
  1985年   57923篇
  1984年   44183篇
  1983年   37313篇
  1982年   23116篇
  1981年   20663篇
  1980年   19248篇
  1979年   39574篇
  1978年   28348篇
  1977年   23740篇
  1976年   22015篇
  1975年   22810篇
  1974年   27121篇
  1973年   26091篇
  1972年   24357篇
  1971年   22326篇
  1970年   20831篇
  1969年   19387篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.

Aims

To obtain an overview of the management and outcomes of children aged 18 years or younger diagnosed with differentiated thyroid carcinoma of follicular cell origin across the UK, by collecting and analysing data from the limited number of centres treating these patients. This multicentre data might provide a more realistic perspective than single-institution series.

Materials and methods

Six centres submitted data extracted from historical records on patients aged 18 years or younger, diagnosed between 1964 and 2017. The univariate and multivariable Cox proportional hazard model was used to identify potential predictors of progression-free survival, using national data as a control.

Results

Data on 166 patients were available for analysis. Females (74%) were predominant, and the age ranged from 3 to 19 years at diagnosis, mean 14.1 years. Nodal metastases were present in 51%; 12% had distant metastases. After surgery, 95% received radioactive iodine (39% on more than one occasion) and 4% received external beam radiotherapy. With a median follow-up duration of 5 years, 69% are alive with no evidence of disease; 20% are alive with a raised thyroglobulin level as the only evidence of residual disease; 6% have residual structural disease detectable on imaging; 2% have died, from cerebral metastases.

Conclusion

Despite most patients having advanced disease at presentation, outcomes are very good. A national prospective registry should allow systematic collection of good-quality data and may facilitate research to further improve outcomes.  相似文献   
92.
In a prospective study, we sought to determine acceptability of linkage of administrative and clinical trial data among Canadian patients and Research Ethics Boards (REBs). The goal is to develop a more harmonized approach to data, with potential to improve clinical trial conduct through enhanced data quality collected at reduced cost and inconvenience for patients. On completion of the original LY.12 randomized clinical trial in lymphoma (NCT00078949), participants were invited to enrol in the Long-term Innovative Follow-up Extension (LIFE) component. Those consenting to do so provided comprehensive identifying information to facilitate linkage with their administrative data. We prospectively designed a global assessment of this innovative approach to clinical trial follow-up including rates of REB approval and patient consent. The pre-specified benchmark for patient acceptability was 80%. Of 16 REBs who reviewed the research protocol, 14 (89%) provided approval; two in Quebec declined due to small patient numbers. Of 140 patients invited to participate, 115 (82%, 95% CI 76 to 88%) from across 9 Canadian provinces provided consent and their full name, date of birth, health insurance number and postal code to facilitate linkage with their administrative data for long-term follow-up. Linkage of clinical trial and administrative data is feasible and acceptable. Further collaborative work including many stakeholders is required to develop an optimized secure approach to research. A more coordinated national approach to health data could facilitate more rapid testing and identification of new effective treatments across multiple jurisdictions and diseases from diabetes to COVID-19.  相似文献   
93.
Abstract

Background

Across the spectrum of patient care for opioid overdose, an important, yet frequently overlooked feature is the bystander, or witness to the overdose event. For other acute medical events such as cardiac arrest and stroke, research supports that the presence of a bystander is associated with better outcomes. Despite the similarities, however, this well-established conceptual framework has yet to be applied in the context of overdose patient outcomes. The objective of this study was to assess the association between the nature of the bystander-patient relationship and prehospital care measures in patients being treated for opioid overdose.  相似文献   
94.
95.
96.
97.
Background MMR proficient (pMMR) colorectal cancer (CRC) is usually unresponsive to immunotherapy. Recent data suggest that ibrutinib may enhance the anti-tumour activity of anti-PD-1 immunotherapy. In this study, we evaluated the safety and efficacy of ibrutinib plus pembrolizumab in refractory metastatic CRC.Methods This was a phase 1/2 study in patients with refractory metastatic pMMR CRC. The primary endpoints for phases 1 and 2 were maximum tolerated dose (MTD) and disease control rate, respectively. The secondary endpoints were safety, progression-free survival (PFS) and overall survival (OS).Results A total of 40 patients were enrolled. No dose-limiting toxicity was observed, and MTD was not identified. The highest tested dose of ibrutinib, 560 mg once daily, was combined with a fixed dose of pembrolizumab 200 mg every 3 weeks for the phase 2 portion. The most common grade 3/4 treatment-related adverse events were anaemia (21%), fatigue (8%) and elevated alkaline phosphatase (8%). Among 31 evaluable patients, 8 (26%) achieved stable disease, and no objective response was observed. The median PFS and OS were 1.4 and 6.6 months, respectively.Conclusion Ibrutinib 560 mg daily plus pembrolizumab 200 mg every 3 weeks appears to be well tolerated with limited anti-cancer activity in metastatic CRC.ClinicalTrials.gov identifier NCT03332498.Subject terms: Cancer immunotherapy, Colorectal cancer  相似文献   
98.
99.
100.
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