全文获取类型
收费全文 | 54008篇 |
免费 | 2951篇 |
国内免费 | 1585篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 309篇 |
妇产科学 | 59篇 |
基础医学 | 2441篇 |
口腔科学 | 52篇 |
临床医学 | 8665篇 |
内科学 | 16400篇 |
皮肤病学 | 77篇 |
神经病学 | 3951篇 |
特种医学 | 2283篇 |
外科学 | 2038篇 |
综合类 | 11824篇 |
预防医学 | 1885篇 |
眼科学 | 48篇 |
药学 | 5774篇 |
67篇 | |
中国医学 | 2577篇 |
肿瘤学 | 77篇 |
出版年
2024年 | 90篇 |
2023年 | 522篇 |
2022年 | 1213篇 |
2021年 | 1699篇 |
2020年 | 1622篇 |
2019年 | 1207篇 |
2018年 | 1247篇 |
2017年 | 1367篇 |
2016年 | 1576篇 |
2015年 | 1646篇 |
2014年 | 3763篇 |
2013年 | 3399篇 |
2012年 | 3416篇 |
2011年 | 3656篇 |
2010年 | 3099篇 |
2009年 | 2956篇 |
2008年 | 2952篇 |
2007年 | 3021篇 |
2006年 | 2925篇 |
2005年 | 2466篇 |
2004年 | 1938篇 |
2003年 | 1727篇 |
2002年 | 1483篇 |
2001年 | 1362篇 |
2000年 | 1234篇 |
1999年 | 1039篇 |
1998年 | 833篇 |
1997年 | 755篇 |
1996年 | 549篇 |
1995年 | 495篇 |
1994年 | 448篇 |
1993年 | 363篇 |
1992年 | 299篇 |
1991年 | 283篇 |
1990年 | 245篇 |
1989年 | 200篇 |
1988年 | 196篇 |
1987年 | 204篇 |
1986年 | 143篇 |
1985年 | 180篇 |
1984年 | 140篇 |
1983年 | 90篇 |
1982年 | 93篇 |
1981年 | 69篇 |
1980年 | 61篇 |
1979年 | 57篇 |
1978年 | 66篇 |
1977年 | 30篇 |
1976年 | 37篇 |
1973年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
《Revista portuguesa de cardiologia》2022,41(4):299-307
AimsMyocardial strain analysis enables more precise assessment of cardiac performance but is relatively load dependent. New tools have been developed with afterload adjustment. Our objective was to assess myocardial work (MW) in patients with repaired aortic coarctation (rACo).MethodsProspective study of consecutive patients with rACo who underwent a routine transthoracic echocardiogram in 2018 and 2019 at our center. Patients with significant aortic valve disease, pacemaker, or other congenital heart diseases (except for mild bicuspid aortic valve disease) were excluded. Global longitudinal strain with two dimensional speckle tracking analysis and MW were obtained (GWI:Global Work Index; GCW: Global Constructive Work; GWW: Global Wasted Work; GWE: Global Work Efficiency). Blood pressure was measured in the patient's right arm.ResultsWe included 42 patients in the analysis, mean age of 37±10 years, 38% males. In this group, 52% had hypertension and 64% had a concomitant bicuspid aortic valve. In comparison to previously published reference values, patients with rACo had significantly lower GWI (1807 vs. 1896 mmHg%) and GCW (2173 vs. 2232 mmHg%) (p<0.001), particularly in males. Systolic blood pressure is an independent predictor for GWI (β=0.432) and for GCW (β=0.534) and GLS an independent predictor of all MW parameters (β>0.594). Neither age nor gender were independent predictors.ConclusionsIn patients with rACo, there are some signs of left ventricular dysfunction with a reduction in GCW and GWI and with preserved GWE, despite normal ejection fraction and strain. 相似文献
3.
4.
《The Journal for Nurse Practitioners》2022,18(2):245-247
Transient stress hyperglycemia in the setting of acute myocardial infarction is a frequent phenomenon. Its transient nature should not dissuade the clinician from management of elevated blood glucose in a patient after an ST-elevation myocardial infarction. This case presents an adult patient after an ST-elevation myocardial infarction with transient stress hyperglycemia and the evidence used to identify optimal pharmacologic management and secondary prevention. 相似文献
5.
6.
目的:探讨血化瘀方联合针灸治疗对脑梗后遗症患者脑血管血液流变动力学及神经功能的影响。方法:选取2016年1月至2017年1月沈阳市第二中医医院收治脑梗后遗症患者120例作为研究对象,对照组61例患者接受针灸治疗;观察组59例患者接受活血化瘀方联合针灸治疗。2组连续治疗30 d。比较2组患者脑血流流变学指标、神经功能评分、中医证候积分、临床疗效。结果:治疗前2组患者脑部平均血流速度、左侧椎动脉血流量、右侧椎动脉血流量、基底动脉血流量比较,差异无统计学意义(P 0. 05)。治疗后观察组患者脑部平均血流速度、左侧椎动脉血流量、右侧椎动脉血流量、基底动脉血流量大于对照组(P 0. 05)。治疗前2组患者NIHSS评分、MMSE评分比较,差异无统计学意义(P 0. 05)。治疗后观察组患者NIHSS评分显著低于对照组,MMSE评分高于对照组(P 0. 05)。治疗前2组患者头晕目眩、语言謇涩、半身不遂、患侧麻木、舌苔白腻证候评分比较,差异无统计学意义(P 0. 05)。治疗后研究患者头晕目眩、语言謇涩、半身不遂、患侧麻木、舌苔白腻证候评分显著低于对照组(P 0. 05)。2组患者临床疗效比较,差异有统计学意义(Z=-5. 626,P=0. 000)。结论:活血化瘀方联合针灸能改善脑梗后遗症患者脑血管血液流变动力学指标,保护神经功能。 相似文献
7.
Philip S. Vendittelli Bassent Botros Howard S. Rosman Viren Govindaraju Anwar Zaitoun Tariq S. Marroush 《The American journal of the medical sciences》2019,357(4):333-337
Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality. 相似文献
8.
9.
Assessment of Myocardial Infarct Size by Three‐Dimensional and Two‐Dimensional Speckle Tracking Echocardiography: A Comparative Study to Single Photon Emission Computed Tomography 下载免费PDF全文
10.
Context: Baicalin has many pharmacological activities, including protective function against myocardial ischemia by antioxidant effects and free radical scavenging activity. However, its rapid elimination half-life in plasma and poor water solubility limits its clinical efficacy.Objective: Novel baicalin-loaded PEGylated nanostructured lipid carriers (BN-PEG-NLC) were developed to improve bioavailability of BN, to prolong retention time in vivo and to enhance its protective effect.Methods: In this study, BN-PEG-NLC were prepared by the emulsion-evaporation and low temperature-solidification method using a mixture of glycerol monostearate and polyethylene glycol monostearate as solid lipids, and oleic acid as the liquid lipid. The physicochemical properties of NLC were characterized. The pharmacokinetic and pharmacodynamic behaviors of BN-PEG-NLC or BN-NLC were evaluated in acute MI rats.Results and discussion: The particle size, zeta potential, and entrapment efficiency for BN-PEG-NLC were observed as 83.9?nm, ?32.1?mV, and 83.5%, respectively. The release profiles of BN from both BN-PEG-NLC and BN-NLC were fitted to the Ritger–Peppas modal, which presented burst release initially and prolonged release afterwards. Pharmacokinetics results indicated that BN-PEG-NLC exhibited a 7.2-fold increase in AUC in comparison to BN solution, while a 3-fold increase in comparison to BN-NLC. Biodistribution results revealed that BN-PEG-NLC exhibited higher heart drug concentration compared with BN-NLC as well as BN solution. In the present study, BN-PEG-NLC significantly ameliorated infarct size.Conclusion: The results of the present study imply that PEG-NLC could be the biocompatible carriers for heart-targeted drug delivery to improve myocardial ischemia. 相似文献