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   101536篇
  免费   5398篇
  国内免费   345篇
耳鼻咽喉   1282篇
儿科学   3011篇
妇产科学   2499篇
基础医学   14096篇
口腔科学   2223篇
临床医学   8443篇
内科学   24172篇
皮肤病学   2183篇
神经病学   9096篇
特种医学   3251篇
外国民族医学   32篇
外科学   12392篇
综合类   469篇
一般理论   26篇
预防医学   9277篇
眼科学   1662篇
药学   6797篇
中国医学   275篇
肿瘤学   6093篇
  2023年   602篇
  2022年   459篇
  2021年   2305篇
  2020年   1437篇
  2019年   2291篇
  2018年   4487篇
  2017年   2880篇
  2016年   2234篇
  2015年   2446篇
  2014年   3148篇
  2013年   4478篇
  2012年   6864篇
  2011年   6954篇
  2010年   3744篇
  2009年   3271篇
  2008年   5949篇
  2007年   6026篇
  2006年   5669篇
  2005年   5718篇
  2004年   5370篇
  2003年   5023篇
  2002年   4756篇
  2001年   2366篇
  2000年   2473篇
  1999年   2024篇
  1998年   655篇
  1997年   452篇
  1996年   429篇
  1995年   435篇
  1994年   378篇
  1993年   353篇
  1992年   1074篇
  1991年   921篇
  1990年   909篇
  1989年   818篇
  1988年   725篇
  1987年   748篇
  1986年   661篇
  1985年   614篇
  1984年   445篇
  1983年   363篇
  1982年   222篇
  1979年   320篇
  1978年   238篇
  1974年   249篇
  1973年   244篇
  1972年   242篇
  1971年   238篇
  1969年   212篇
  1968年   210篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Odontology - The purpose of this study was to investigate whether the root perforation repair with mineral aggregate-based cements affects the retention of customized fiberglass posts to bovine...  相似文献   
2.
3.
IntroductionThe current paradigm of the management of rheumatoid arthritis (RA) recommends achieving a state of remission or low disease activity through the treat-to-target strategy. Our study assesses adherence to this strategy.MethodPatients with RA (ACR-EULAR 2010 criteria) were included. From each centre, 19 patients were randomly selected. Clinical histories (CH) were assessed by independent auditors, checking compliance with predefined quality criteria. The study was approved by ethics committees.ResultsWe included 856 patients (mean age 54 years; 71% women). The use of a combined index (CI) was recorded in 61% of cases. Visits were recorded every 4 weeks using a CI in 4% of CH while attempts were made to achieve remission. Monitoring of disease activity every 6–8 months after reaching the target was recorded in 73% of cases.ConclusionsThe implementation of the treat-to-target strategy is barely recorded in patients with RA in routine clinical practice.  相似文献   
4.
BackgroundAdjuvant chemotherapy, postoperative radiation (PORT), and prophylactic cranial irradiation (PCI) have been individually examined in limited-stage small cell lung cancer (SCLC). There is a paucity of data on the effectiveness of each adjuvant treatment modality when used in combination after surgical resection of SCLC.MethodsData were collected from 5 cancer centers on all patients with limited-stage SCLC who underwent surgical resection between 1986 and 2019. Univariate and multivariable models were conducted to identify predictors of long-term outcomes, focusing on freedom from recurrence and survival benefit of adjuvant chemotherapy, PORT, and PCI.ResultsA total of 164 patients were analyzed. Multivariable Cox regression analysis did not identify any adjuvant therapies to significantly influence recurrence in this cohort. Specifically, PORT was not associated with a significant influence on locoregional recurrence and PCI was not significantly associated with intracranial outcomes. Adjuvant chemotherapy improved survival in all stage I through III disease (hazard ratio, 0.49; 95% confidence interval, 0.29-0.81; P = .005) and even in pathologically node negative patients (hazard ratio, 0.49; 95% confidence interval, 0.27-0.91; P = .024). Although PCI was found to improve survival in univariate analysis, it was not significant in a multivariable model. PORT was not found to affect survival on either univariate or multivariable analysis.ConclusionsThis is among the largest multi-institutional studies on surgically resected limited-stage SCLC. Our results highlight survival benefit of adjuvant chemotherapy, but did not identify a statistically significant influence from mediastinal PORT or PCI in our cohort. Larger prospective studies are needed to determine the benefit of PORT or PCI in a surgically resected limited-stage SCLC population.  相似文献   
5.
Background and aimsDeterioration of anthropometric and lung function parameters was shown to precede the onset of cystic fibrosis-related diabetes (CFRD) in adults. In children, studies have been conducted in small cohorts with relatively short observation period. Study objectives were to document the longitudinal trends of anthropometric, pulmonary, nutritional and metabolic parameters from cystic fibrosis (CF) diagnosis to the ascertainment of abnormal glucose tolerance and identify parameters associated with the incidence of such abnormalities in a pediatric CF cohort.Methods and resultsRetrospective cohort study of 281 children with CF. Longitudinal trends of anthropometric, lung function, nutritional and metabolic data were generated from CF diagnosis to the ascertainment of abnormal glucose tolerance defined as the presence of either impaired glucose tolerance (IGT), unconfirmed CFRD or CFRD. Cox models and Kaplan–Meier curves were used to identify factors associated with developing abnormal glucose tolerance.Forty-five percent of cohort had normal glucose tolerance (NGT), 27% IGT, 10% unconfirmed CFRD and 18% CFRD. Children who developed CFRD displayed lower height z-scores from a very early age. Conversely, HbA1c levels began to rise closer to CFRD ascertainment. Height z-scores (HR: 0.45; CI 95% [0.29–0.69]) and HbA1c (HR: 2.43; CI 95% [1.86–3.18]) in years preceding ascertainment were associated with the risk of developing CFRD.ConclusionChildren who developed CFRD display distinctive trends for height z-scores from a very early age, whereas HbA1c appears as a marker of established glucose metabolism derangements.  相似文献   
6.
BackgroundThe optimal regimen for intravenous administration of intraoperative fluids remains unclear. Our goal was to analyze intraoperative crystalloid volume administration practices and their association with postoperative outcomes.MethodsWe extracted clinical data from two multicenter observational studies including adult patients undergoing colorectal surgery and total hip (THA) and knee arthroplasty (TKA). We analyzed the distribution of intraoperative fluid administration. Regression was performed using a general linear model to determine factors predictive of fluid administration. Patient outcomes and intraoperative crystalloid utilization were summarized for each surgical cohort. Regression models were developed to evaluate associations of high or low intraoperative crystalloid with the likelihood of increased postoperative complications, mainly acute kidney injury (AKI) and hospital length of stay (LOS).Results7,580 patients were included. The average adjusted intraoperative crystalloid infusion rate across all surgeries was to 7.9 (SD 4) mL/kg/h. The regression model strongly favored the type of surgery over other patient predictors. We found that high fluid volume was associated with 40% greater odds ratio (OR 1.40; 95% confidence interval1.01-1.95, p = 0.044) of postoperative complications in patients undergoing THA, while we found no associations for the other types of surgeries, AKI and LOSConclusionsA wide variability was observed in intraoperative crystalloid volume administration; however, this did not affect postoperative outcomes.  相似文献   
7.
International Journal of Clinical Oncology - Immune-checkpoint inhibitors (ICIs) are standard treatments for metastatic non-small cell lung cancer (NSCLC). Patients with poor performance status...  相似文献   
8.
9.
结核病与糖尿病均是临床上的常见病和多发病,两者可合并存在,相互影响。活动性结核病作为感染因素可加重糖尿病病情,而糖尿病患者又是发生结核病的高危人群,结核病与糖尿病双重负担将成为重大的全球公共卫生问题。因此,需重视结核病与糖尿病共病的治疗管理。本共识重点介绍了结核病与糖尿病共病的危害、发病机制、双向筛查、临床特点、诊断、治疗和管理等内容。  相似文献   
10.
IntroductionThe main challenge of Parkinson's disease in women of childbearing age is managing symptoms and drugs during pregnancy and breastfeeding. The increase in the age at which women are having children makes it likely that these pregnancies will become more common in future.ObjectivesThis study aims to define the clinical characteristics of women of childbearing age with Parkinson's disease and the factors affecting their lives, and to establish a series of guidelines for managing pregnancy in these patients.ResultsThis consensus document was developed through an exhaustive literature search and a discussion of the available evidence by a group of movement disorder experts from the Spanish Society of Neurology.ConclusionsParkinson's disease affects all aspects of sexual and reproductive health in women of childbearing age. Pregnancy should be well planned to minimise teratogenic risk. A multidisciplinary approach should be adopted in the management of these patients in order to take all relevant considerations into account.  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