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   100085篇
  免费   7139篇
  国内免费   2753篇
耳鼻咽喉   597篇
儿科学   1815篇
妇产科学   592篇
基础医学   5199篇
口腔科学   793篇
临床医学   12419篇
内科学   13805篇
皮肤病学   1231篇
神经病学   4202篇
特种医学   2856篇
外国民族医学   10篇
外科学   6928篇
综合类   19825篇
现状与发展   6篇
一般理论   1篇
预防医学   8772篇
眼科学   1069篇
药学   17896篇
  576篇
中国医学   7425篇
肿瘤学   3960篇
  2024年   204篇
  2023年   1627篇
  2022年   3003篇
  2021年   4652篇
  2020年   4644篇
  2019年   3156篇
  2018年   3113篇
  2017年   3650篇
  2016年   4383篇
  2015年   4051篇
  2014年   8902篇
  2013年   8271篇
  2012年   7205篇
  2011年   7063篇
  2010年   5597篇
  2009年   4734篇
  2008年   4460篇
  2007年   4582篇
  2006年   3937篇
  2005年   3286篇
  2004年   2598篇
  2003年   2282篇
  2002年   1778篇
  2001年   1624篇
  2000年   1310篇
  1999年   1194篇
  1998年   958篇
  1997年   849篇
  1996年   767篇
  1995年   687篇
  1994年   639篇
  1993年   486篇
  1992年   485篇
  1991年   467篇
  1990年   415篇
  1989年   365篇
  1988年   351篇
  1987年   264篇
  1986年   255篇
  1985年   299篇
  1984年   244篇
  1983年   145篇
  1982年   185篇
  1981年   146篇
  1980年   123篇
  1979年   122篇
  1978年   93篇
  1977年   99篇
  1976年   64篇
  1975年   55篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Introduction: There are at the minimum two major, quite different approaches to advance drug discovery. The first being the target-based drug discovery (TBDD) approach that is commonly referred to as the molecular approach. The second approach is the phenotype-based drug discovery (PBDD), also known as physiology-based drug discovery or empirical approach.

Area covered: The authors discuss, herein, the need for developing radiation countermeasure agents for various sub-syndromes of acute radiation syndromes (ARS) following TBDD and PBDD approaches. With time and continuous advances in radiation countermeasure drug development research, the expectation is to have multiple radiation countermeasure agents for each sub-syndrome made available to radiation exposed victims.

Expert opinion: The majority of the countermeasures currently being developed for ARS employ the PBDD approach, while the TBDD approach is clearly under-utilized. In the future, an improved drug development strategy might be a ‘hybrid’ strategy that is more reliant on TBDD for the initial drug discovery via large-scale screening of potential candidate agents, while utilizing PBDD for secondary screening of those candidates, followed by tertiary analytics phase in order to pinpoint efficacious candidates that target the specific sub-syndromes of ARS.  相似文献   

92.

Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Methods

In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.

Results

AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.

Conclusions

These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium.  相似文献   
93.
目的探讨心理护理在ICU重症护理中的效果。方法选定本科于2017年6月-2019年8月收诊的ICU重症患者86例,等距抽样法分为对照组(43例,传统式护理)与观察组(43例,心理护理联合传统式护理)2组,比较2组ICU重症患者的护理满意率、情绪评分(SAS/SDS)指标。结果观察组ICU重症患者干预结束后的满意率高于对照组(P<0.05);观察组ICU重症患者干预结束后的SAS评分(32.52±3.26)分、SDS评分(30.09±3.45)分均低于对照组(P<0.05)。结论心理护理应用于ICU重症患者,可对其满意度、安全性进行保证。  相似文献   
94.
目的研究在肝癌介入术治疗患者中应用心理护理干预的临床价值。方法本文数据计算目标是2018年1月-2019年6月的60例肝癌介入术治疗患者,以随机数字表法的形式进行分组研究,常规组(n=30)开展一般护理干预,心理组(n=30)开展心理护理干预,比较心理组与常规组肝癌介入术治疗患者临床护理情况。结果心理组肝癌介入术治疗患者治疗后临床护理满意度、焦虑评分、抑郁评分与常规组比较,两组治疗后肝癌介入术治疗患者焦虑评分、抑郁评分与治疗前比较,P<0.05,差异有统计学意义。结论将心理护理干预应用在肝癌介入术治疗患者中可提升护理满意度。  相似文献   
95.
The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery.  相似文献   
96.
目的 分析重症医学科PBL教学法在临床心肺复苏术教学中的应用效果.方法 本次实验的开展基础数据选择2016年9月—2018年7月进入医院重症医学科实习学生64例,按照学生自身意愿以及学校安排将参与实验学生分为均数相同的两个小组(对照组、观察组),每组实验人数均为32例,其中对照组(n=32)采用传统教学方法 ,观察组(n=32)则应用PBL教学法教学,对比两组学生在学期结束后整体的学习质量情况和教学满意率.结果 观察组学生经过测试后理论知识和专业技能得分均对比对照组更高,教学效果更加理想,观察组学生对于教学的满意率评价更高,P<0.05.结论 重症医学科临床心肺复苏术教学中应用PBL教学法,将理论与实践进行结合,对教学方法 进行改进,全面提升学生的思维理解能力,培养良好的动手能力,促进理论教学与实践的结合,为学生以后的职业生涯提供更加理想的条件.  相似文献   
97.
目的探讨聪耳通窍汤联合耳针治疗老年神经性耳鸣患者的近远期疗效。方法选取耳鼻喉科门诊收治的老年神经性耳鸣患者136例,按随机数字表法分组,对照组68例予以耳针治疗,研究组68例在对照组基础上予以聪耳通窍汤治疗。检测比较两组间近、远期临床疗效、甲襞微循环指标、血液流变学指标以及不良反应发生率。结果治疗后,对照组总有效率为67.64%(46/68)低于研究组总有效率83.82%(57/68),具有统计学意义(P<0.05);随访6个月后,对照组总有效率64.71%(44/68)低于研究组总有效率89.71%(61/68),具有统计学意义(P<0.05);与对照组比较,研究组治疗后甲襞微循环襻周积分、管襻积分、流态积分及总积分较低,治疗后血浆黏度、高切全血黏度、低切全血黏度及红细胞压积较低,差异具有统计学意义(P<0.05);治疗中出现的不良反应为恶心、腹胀、针刺部位疼痛,两组间不良反应发生率无统计学差异(P>0.05)。结论聪耳通窍汤联合耳针治疗老年神经性耳鸣患者的近远期疗效均较好,能明显改善患者微循环状态及血液流变学指标,减轻内耳循环障碍,具有较高安全性。  相似文献   
98.
99.
《Vaccine》2016,34(50):6316-6322
ObjectiveAir pollution, weather condition and influenza are known risk factors of acute coronary syndrome (ACS) among elderly people. The influenza vaccine (IV) has been shown to reduce major cardiovascular events. The purpose of this study was to compare resistance to air pollution and weather factors causing ACS between vaccinated and less-vaccinated elderly people.MethodsA case–crossover design was applied to 1835 elderly ACS patients who were obtained from the 1-million sample of Taiwan National Health Insurance Research Data with inclusion criteria: (1) the first diagnosis of ACS was in cold season and at age 68 or more, (2) had received the free IV program at least once during the period 3 years before the ACS. They were stratified into two groups: 707 had received flu vaccinations for all the 3 years and the remaining 1128 had not. The measurements of air pollutants, temperature, and humidity corresponding to each of the 3 days prior to the ACS diagnosis date were retrieved from the data banks of the Taiwan Environmental Protection Administration and Central Weather Bureau.FindingsIncreases in air pollution concentrations of CO, NO2, PM10 or PM2.5 and decreases in temperature significantly influenced the risk of ACS for the non-continuously vaccinated elderly population; however, less significant effects were observed for the continuously vaccinated population.ConclusionConsecutive influenza vaccination may potentially offer resistance against the detrimental effects of air pollution and changes in temperature in frail elderly adults with ACS. Future studies are needed to directly assess the interaction effect between the vaccination and environmental factors on ACS.  相似文献   
100.
《Annals of hepatology》2019,18(3):514-516
Gyromitra esculenta, also known as “false morel” is one of the most poisonous mushrooms. This species is found all over the world, growing in coniferous forest in early spring time. Common manifestation of poisoning includes gastrointestinal symptoms which include varied degrees of liver impairment.We describe three cases: acute liver injury, acute liver failure and acute-on-chronic liver failure due to G. esculenta poisoning. At admission patients presented with encephalopathy and features of liver failure. Two of them recovered completely following supportive management while the remaining patient who also had preexisting liver disease developed multiorgan failure and subsequently died.Although a rare occurrence, G. esculenta poisoning should be considered in the differential diagnosis of acute liver failure.  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