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   8005篇
  免费   827篇
  国内免费   222篇
耳鼻咽喉   48篇
儿科学   145篇
妇产科学   63篇
基础医学   707篇
口腔科学   157篇
临床医学   1322篇
内科学   873篇
皮肤病学   38篇
神经病学   425篇
特种医学   360篇
外科学   493篇
综合类   1303篇
现状与发展   1篇
预防医学   719篇
眼科学   120篇
药学   716篇
  3篇
中国医学   1378篇
肿瘤学   183篇
  2024年   7篇
  2023年   106篇
  2022年   201篇
  2021年   377篇
  2020年   362篇
  2019年   298篇
  2018年   303篇
  2017年   363篇
  2016年   400篇
  2015年   351篇
  2014年   652篇
  2013年   617篇
  2012年   581篇
  2011年   616篇
  2010年   466篇
  2009年   395篇
  2008年   331篇
  2007年   321篇
  2006年   284篇
  2005年   249篇
  2004年   234篇
  2003年   198篇
  2002年   181篇
  2001年   154篇
  2000年   119篇
  1999年   101篇
  1998年   98篇
  1997年   64篇
  1996年   73篇
  1995年   82篇
  1994年   71篇
  1993年   49篇
  1992年   52篇
  1991年   46篇
  1990年   39篇
  1989年   25篇
  1988年   25篇
  1987年   30篇
  1986年   16篇
  1985年   27篇
  1984年   24篇
  1983年   15篇
  1982年   7篇
  1981年   9篇
  1980年   11篇
  1979年   3篇
  1978年   9篇
  1977年   4篇
  1976年   5篇
  1975年   2篇
排序方式: 共有9054条查询结果,搜索用时 31 毫秒
1.
Evaluation of the ossification of the medial clavicular epiphysis plays a key role in forensic age estimation. The purpose of the present study was to assess a new numerical cut-off at the age of 18 years, taking into consideration Magnetic Resonance (MR) images of the medial clavicular epiphysis. We analyzed 163 MR scans of Italian subjects aged between 14 and 25 years. Using the data obtained we calculated two ratios: REM-1 (ratio between the length of the whole epiphysis and the length of the metaphysis) and REM-2 (ratio between the length of epiphyseal-metaphyseal fusion and the length of the metaphysis). In 68 out of 163 cases it was not possible to measure REM-2. The reproducibility was demonstrated using the Intraclass Correlation Coefficient (ICC) (Cronbach’s alpha > 0.80). REM-1 and REM-2 were compared in each category of age (adult and minor) by the Wilcoxon signed-rank test. The cut-off points for measurements of REM-1 and REM-2 were determined by logistic regression. For REM-1, the cut-off scores were 0.83 for all individuals (accuracy = 94.77%) and males (accuracy = 96.05%), and 0.86 for females (accuracy = 92.30%). For REM-2, the cut-off values were 0.40 for all individuals and males (accuracy = 100.00%), and 0.41 for females (accuracy = 100.00%). Finally, receiver operating characteristic (ROC) curves for age classification based on REM-1 and REM-2 were constructed, showing that REM-2 had the highest discriminative power. Thus, a new cut-off model for predicting the age of majority has been introduced, conducting a quantitative analysis thanks to the use of a high-resolution imaging tool.  相似文献   
2.
《Cancer cell》2022,40(10):1223-1239.e6
  1. Download : Download high-res image (205KB)
  2. Download : Download full-size image
  相似文献   
3.
4.
AimsChild growth is one of the important health indicators in pediatric care. Few studies focused on the impact of prenatal exposure to gestational diabetes mellitus (GDM) on growth trajectories particular in early years of childhood. The aim of this study was identifying growth pattern of GDM exposed offspring's, comparison with new WHO child growth standards.Methods and materialsIn a population-based Longitudinal study 438 infants exposed to gestational diabetes in utero, aged 0–24 months, born between 2014 and 2016 with at least 9 visits in first 2 years of life were enrolled. Twenty health centers of Ahvaz city (Capital of Khuzestan province, located in south western of Iran) and two referral centers for neonatal hypothyroidism involved the study.ResultsOf 438 GDM exposed infants, 54.6% were boys. Incidence of low birth weight and macrosomia were 4.6% and 8.7% respectively.Results4.6% had birth weight less than 2500gr and 8.7% was rate of macrosomia. Boys had higher weight and BMI than girls. Peak of BMI was 17.8 (±2.07) at 6 months after Gender was significant factor in predicted of BMI growth trajectories in GDM exposed children (p = 0.001). BMI in GDM exposed infants, in first 2 years of life was higher than WHO growth standards 2006 (P < 0.01).ConclusionMedians of BMI in GDM exposed infants in all measures was higher than WHO reference data 2006 (P < 0.01). Obesity prevention programs must be priority in GDM exposed infants.  相似文献   
5.

Background

The randomized EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial reported a similar rate of the 3-year composite primary endpoint of death, myocardial infarction (MI), or stroke in patients with left main coronary artery disease (LMCAD) and site-assessed low or intermediate SYNTAX scores treated with percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). Whether these results are consistent in high-risk patients with diabetes, who have fared relatively better with CABG in most prior trials, is unknown.

Objectives

In this pre-specified subgroup analysis from the EXCEL trial, the authors sought to examine the effect of diabetes in patients with LMCAD treated with PCI versus CABG.

Methods

Patients (N = 1,905) with LMCAD and site-assessed low or intermediate CAD complexity (SYNTAX scores ≤32) were randomized 1:1 to PCI with everolimus-eluting stents versus CABG, stratified by the presence of diabetes. The primary endpoint was the rate of a composite of all-cause death, stroke, or MI at 3 years. Outcomes were examined in patients with (n = 554) and without (n = 1,350) diabetes.

Results

The 3-year composite primary endpoint was significantly higher in diabetic compared with nondiabetic patients (20.0% vs. 12.9%; p < 0.001). The rate of the 3-year primary endpoint was similar after treatment with PCI and CABG in diabetic patients (20.7% vs. 19.3%, respectively; hazard ratio: 1.03; 95% confidence interval: 0.71 to 1.50; p = 0.87) and nondiabetic patients (12.9% vs. 12.9%, respectively; hazard ratio: 0.98; 95% confidence interval: 0.73 to 1.32; p = 0.89). All-cause death at 3 years occurred in 13.6% of PCI and 9.0% of CABG patients (p = 0.046), although no significant interaction was present between diabetes status and treatment for all-cause death (p = 0.22) or other endpoints, including the 3-year primary endpoint (p = 0.82) or the major secondary endpoints of death, MI, or stroke at 30 days (p = 0.61) or death, MI, stroke, or ischemia-driven revascularization at 3 years (p = 0.65).

Conclusions

In the EXCEL trial, the relative 30-day and 3-year outcomes of PCI with everolimus-eluting stents versus CABG were consistent in diabetic and nondiabetic patients with LMCAD and site-assessed low or intermediate SYNTAX scores.(Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776)  相似文献   
6.
目的:探讨耳穴贴压联合涌泉穴按摩治疗老年原发性高血压的效果及对患者血压变异性(BPV)的影响。方法:将94例老年原发性高血压患者随机分为对照组(n=47)和观察组(n=47)。常规西医治疗基础上,观察组给予王不留行籽耳穴贴压联合涌泉穴按摩治疗。比较两组治疗前后收缩压(SBP)、舒张压(DBP)水平、SBP/DBP下降幅度并评估降压疗效,BPV根据24 h动态血压监测结果评估,计算两组治疗前后24h SBP标准差(24h SBP)、24h DBP标准差(24h DBP)、白天SBP标准差(dSSD)、白天DBP标准差(dDSD)、夜间SBP标准差(nSSD)和夜间DBP标准差(nDSD),记录两组治疗期间不良反应情况。结果:观察组治疗后SBP、DBP水平和下降幅度均优于对照组(P<0.05); 观察组降压总有效率97.87%明显高于对照组82.98%,差异有统计学意义(P<0.05); 对照组治疗后24h SBP、24h DSD、dSSD、dDSD较治疗前有明显下降(P<0.05),观察组治疗后24h SBP、24h DSD、dSSD、dDSD、nSSD显著低于治疗前(P<0.05),观察组治疗后24h SBP、24h DSD、dSSD均显著低于对照组,差异有统计学意义(P<0.05); 两组不良反应以头晕、头痛、恶心和眩晕为主,症状程度均较轻,患者耐受性好,组间不良反应率比较差异均无统计学意义(P<0.05)。结论:常规西医治疗基础上给予中医耳穴贴压联合涌泉穴按摩,不仅能有效降低老年原发性高血压患者血压水平和增益降压疗效,而且能显著降低BPV。  相似文献   
7.
8.
张丽 《新中医》2020,52(2):152-154
目的:观察槟木香散贴敷神阙穴联合蒙脱石散防治阿奇霉素致胃肠道反应的临床效果。方法:根据不同防治措施将163例静脉滴注阿奇霉素的患者分为对照组64例和观察组99例。2组均于静脉滴注阿奇霉素前30 min温水冲服蒙脱石散。观察组于静脉滴注阿奇霉素前30 min将槟木香散调成的药膏贴敷于神阙穴上,持续至滴注完成后2 h。2组均连续观察7天。记录恶心、呕吐、腹痛、腹泻等胃肠道反应发生的例数、发生时间和持续时间,并评价胃肠道反应各症状的程度。结果:治疗后,观察组胃肠道反应发生率为8.08%,低于对照组的23.44%(P<0.01)。观察组胃肠道反应程度轻于对照组(P<0.05)。2组胃肠道反应发生时间比较,差异无统计学意义(P>0.05)。观察组恶心、呕吐、腹痛、腹泻持续的时间均短于对照组(P<0.05)。结论:采用槟木香散贴敷神阙穴联合蒙脱石散干预静脉滴注阿奇霉素的患者,可减少胃肠道不良反应的发生率,减轻不良反应程度,促进胃肠道症状的消除。  相似文献   
9.
10.
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