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   64709篇
  免费   4566篇
  国内免费   2009篇
耳鼻咽喉   185篇
儿科学   932篇
妇产科学   733篇
基础医学   4956篇
口腔科学   542篇
临床医学   9535篇
内科学   22429篇
皮肤病学   213篇
神经病学   2445篇
特种医学   3456篇
外国民族医学   3篇
外科学   4884篇
综合类   10467篇
现状与发展   7篇
预防医学   2087篇
眼科学   516篇
药学   4640篇
  43篇
中国医学   2393篇
肿瘤学   818篇
  2024年   87篇
  2023年   897篇
  2022年   1357篇
  2021年   2610篇
  2020年   2356篇
  2019年   1997篇
  2018年   2098篇
  2017年   1817篇
  2016年   1832篇
  2015年   2031篇
  2014年   3887篇
  2013年   4178篇
  2012年   3234篇
  2011年   3643篇
  2010年   2963篇
  2009年   2825篇
  2008年   3142篇
  2007年   3336篇
  2006年   2885篇
  2005年   2626篇
  2004年   2247篇
  2003年   1948篇
  2002年   1747篇
  2001年   1673篇
  2000年   1305篇
  1999年   1167篇
  1998年   1236篇
  1997年   1249篇
  1996年   1033篇
  1995年   1007篇
  1994年   857篇
  1993年   754篇
  1992年   660篇
  1991年   562篇
  1990年   474篇
  1989年   432篇
  1988年   390篇
  1987年   351篇
  1986年   283篇
  1985年   406篇
  1984年   290篇
  1983年   204篇
  1982年   261篇
  1981年   200篇
  1980年   166篇
  1979年   133篇
  1978年   106篇
  1977年   96篇
  1976年   89篇
  1975年   42篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
目的:探究替米沙坦对冠心病合并糖尿病肾病患者疗效的影响情况。方法:56例探究目标对象均为某院接收的冠心病合并糖尿病肾病患者,挑选时间2018年6月~2019年6月。将"计算机表法"作为分组的参考,分配为参照组(n=28例)执行依那普利治疗,探究组(n=28例)执行替米沙坦治疗。结果:探究组的LVEF、LVEDd、肌酐、24h尿蛋白4项指标与参照组相比,差异有统计学意义(P<0.05);收缩压、舒张压、空腹血糖、餐后2h血糖4项指标与参照组相比,差异没有统计学意义(P>0.05)。结论:冠心病合并糖尿病肾病患者选择替米沙坦治疗后,心室功能的重构以及肾脏预后结局均得到改善,且临床效果比依那普利好,值得借鉴。  相似文献   
44.
45.
目的探讨经皮冠状动脉介入(PCI)和静脉溶栓在急性心肌梗死患者中的应用价值。方法选择我院2013年1月至2014年9月收治的60例急性心肌梗死患者作为研究对象,随机分为实验组和对照组各30例。实验组患者采用PCI治疗,对照组患者采用静脉溶栓治疗,比较两组患者血管再通率、死亡发生率、ST段回落情况、住院时间、近远期不良事件发生率、左室舒张末径和左室射血分数变化情况。结果实验组血管再通率显著高于对照组,差异有统计学意义(P<0.05),而近期和远期不良事件发生率均低于对照组,近期不良事件发生率组间比较差异有统计学意义(P<0.05),而远期不良事件发生率比较差异无统计学意义(P>0.05)。实验组患者死亡发生率、ST段回落和住院时间均低于对照组,差异均有统计学意义(P<0.05)。实验组左室射血分数在术后1个月、3个月和6个月时均显著高于对照组,差异均有统计学意义(P<0.05)。结论急性心肌梗死患者应用PCI治疗可显著提高血管再通率、降低死亡和不良事件发生率,有效改善心功能。  相似文献   
46.
目的 观察参麦注射液治疗冠心痛的临床效果.方法 选取我院2013年4月-2014年1月间收治的冠心病患者94例,依据治疗方案不同分为治疗组48例,对照组46例,2组患者入院均根据病情给予能量合剂、血管扩张剂、减轻心脏负荷药物,并进行对症、溶栓及抗心律失常等常规治疗,治疗组患者在常规治疗的基础上给予参麦注射液静滴治疗,1次/d,用药2周为1疗程;于治疗2疗程后观察治疗效果,并对比2组患者临床症状、心电图改善情况及红细胞超氧化物歧化酶(E-SOD)平均活性,血浆过氧化脂质(P-LPO)、红细胞过氧化脂质(E-LPO)含量变化.结果 治疗组治疗后总有效率显著高于对照组(P<0.05);治疗组胸闷、心悸、心绞痛及ST段下移、T渡低平或倒置患者改善率显著均高于对照组(P<0.05);治疗组治疗后E-SOD活性显著高于对照组,P-LPO、E-LPO含量显著低于对照组(P<0.05).结论 参麦注射液可有效缓解冠心病患者临床症状,降低血中脂质过氧化物浓度,缓解心肌缺血状态.  相似文献   
47.
48.
Introduction: It is important to know how to treat hypertension in patients with coronary artery disease (CAD). The reason for the review was to update this treatment and to discuss the 2015 American Heart Association/American College of Cardiology/American Society of Hypertension 2015 guidelines of treatment of hypertension in patients with CAD.

Areas covered: Studies between 1968 and 2015 were reviewed on treatment of hypertension in patients with CAD using a Medline search, and studies between 1977 and 2015 were reported. Hypertension should be treated with beta blockers and ACE inhibitors or angiotensin receptor blockers (ARBs). Long-acting nitrates are effective antianginal and anti-ischemic drugs. Calcium-channel blockers (CCBs) may be added if angina persists despite beta blockers and long-acting nitrates. The 2015 guidelines recommend that the blood pressure should be < 140/90 mm Hg in patients aged ≤ 80 years and the systolic blood pressure < 150 mm Hg if they are ≥ 80 years.

Expert opinion: Hypertension in patients with CAD should be treated with beta blockers and ACE inhibitors or ARBs. Long-acting nitrates are effective antianginal and anti-ischemic drugs. CCBs may be added if angina persists despite beta blockers and long-acting nitrates. The blood pressure should be < 140/90 mm Hg in patients aged < 80 years and the systolic blood pressure < 150 mm Hg if they are ≥ 80 years.  相似文献   
49.

Background

Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited.

Methods

Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors.

Results

The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581–3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90).

Conclusions

Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase.

Clinical trial registration

Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651.  相似文献   
50.

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   
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