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   8834篇
  免费   736篇
  国内免费   206篇
耳鼻咽喉   50篇
儿科学   77篇
妇产科学   243篇
基础医学   813篇
口腔科学   180篇
临床医学   934篇
内科学   1648篇
皮肤病学   85篇
神经病学   566篇
特种医学   382篇
外国民族医学   5篇
外科学   948篇
综合类   1051篇
现状与发展   1篇
预防医学   563篇
眼科学   106篇
药学   650篇
  12篇
中国医学   490篇
肿瘤学   972篇
  2024年   52篇
  2023年   949篇
  2022年   1284篇
  2021年   1170篇
  2020年   1127篇
  2019年   514篇
  2018年   216篇
  2017年   291篇
  2016年   342篇
  2015年   327篇
  2014年   691篇
  2013年   419篇
  2012年   343篇
  2011年   305篇
  2010年   336篇
  2009年   272篇
  2008年   140篇
  2007年   177篇
  2006年   116篇
  2005年   85篇
  2004年   52篇
  2003年   50篇
  2002年   56篇
  2001年   64篇
  2000年   42篇
  1999年   54篇
  1998年   57篇
  1997年   37篇
  1996年   35篇
  1995年   53篇
  1994年   28篇
  1993年   22篇
  1992年   17篇
  1991年   9篇
  1990年   9篇
  1989年   15篇
  1988年   14篇
  1987年   1篇
  1986年   3篇
  1984年   1篇
  1968年   1篇
排序方式: 共有9776条查询结果,搜索用时 15 毫秒
1.
2.
ObjectiveThere may be gender difference in correlation of diabetes mellitus (DM) and cardiovascular events. We attempt to investigate whether there is gender-heterogeneity in one-year outcomes of atrial fibrillation (AF) patients with DM or not.MethodsPatients who were diagnosed with AF admitted to the emergency departments in the Chinese AF Multicenter Registry study were enrolled. Basic demographics information, initial Blood Pressure and heart rate, medical histories, and treatments of each patient were collected. Follow-up was carried out with a mean duration of one year. The primary endpoint was all-cause mortality and systemic embolism.ResultsA total of 2016 patients were selected from September 2008 and April 2011. All-cause mortality was significantly higher in male AF patients with DM than those without (21.8 % & 13.6 %, P = 0.014). Cox regression analysis showed that there was an interaction between gender and DM for one-year all-cause mortality (P = 0.049). DM was significantly associated with one-year all-cause mortality regardless of univariate analysis (HR = 1.436, 95%CI:1.079–1.911, P = 0.013) or multivariate analysis (HR = 1.418, 95%CI: 1.059–1.899, P = 0.019). For male patients with AF, DM was significantly associated with one-year all-cause mortality (P = 0.048), but not for female patients with AF (P = 0.362).ConclusionDM was independently associated with one-year all-cause mortality in the entire cohort of AF patients. This association was found mainly in male patients with AF, but not in female patients. DM management programs may need to reflect gender difference.  相似文献   
3.
4.
The purpose of this study is to show a very rare complication of acute cocaine poisoning, namely heart rupture. In the present case report, acute cocaine intoxication caused massive myocardial infarction, resulting in heart rupture and cardiac tamponade. A crime scene investigation found a dead body on the street in a drug dealing district. Examination of the body showed no external injuries. A thorough autopsy was performed showing massive cardiac tamponade with 510 ml of blood within the pericardium and full-thickness tissue lesion at the posterior wall of the left ventricle of 3.5 × 3 cm. Histological examination in hematoxylin and eosin was performed and confirmed the interruption of the posterior wall of the left ventricle with the presence of blood. In fact, although the correlation between cocaine and myocardial damage is well established, the relationship between heart rupture and acute cocaine intoxication is an extremely rare event. Moreover, since there are, to date, few reports of similar deaths, our report provides useful information regarding sudden death in a cocaine abuser. It is, therefore, of crucial importance to report this case to the scientific community.  相似文献   
5.
6.
7.
BackgroundComminuted patellar fractures are not rare, and the ideal treatment method remains controversial. The present study was conducted to evaluate effects and compare complications of two different methods used to treat comminuted patellar fractures.MethodsFrom March 2010 to August 2016, 102 cases of 34-C2 or 34-C3 comminuted patellar fractures were treated at our hospital, wherein patients received two different treatments: titanium cable tension band with cerclage method (group A) and intrafragmentary screws with X-shaped plating technique (group B). At follow-ups, articular step-off, range of motion (ROM), Lysholm scores, time of union, and complications were recorded and analyzed. Radiographic and clinical data as well as rate of complications were statistically analyzed.ResultsIn total, 87 patients were included in the final analysis (n = 47 in group A and n = 40 in group B). No significant differences were noted in terms of cost of implant, age, gender, rate of 34-C3 fractures, rate of layered inferior pole fractures, postoperative articular step-off and union time. At 2-year follow-up, average Lysholm scores, ROM and rate of complications were (89.0 ± 4.5), (122°±12°) and (27.7%) in group A and (90.2 ± 3.9), (124°±11°) and (17.5%) in group B, respectively, with no significant differences (p > 0.05). The mean time of surgery in group B was shorter than that in group A with significant difference (p < 0.05).ConclusionsTreatment using the intrafragmentary screws and plate method for amenable comminuted patellar fractures achieved similar complication rate and favorable functional outcomes at the 2-year follow-up, which was comparable to the titanium cable tension band with cerclage method. Thus, the intrafragmentary screws and plate method is effective, safe and convenient for 34-C2/C3 comminuted patellar fractures, especially appropriate for patients with layered fragments.  相似文献   
8.
PurposeTo provide means for calculating the dose received by various tissues of the patient, calculate lung shield, and verify received dose using a phantom as a tool for quality assurance for a planned Total Body Irradiation (TBI) procedure in radiotherapy.MethodUsing Microsoft Visual Basic, MATLAB, and Python, a program for Total Body Irradiation Calculation in Radiotherapy (TBICR) is constructed. It uses patient translation and beam zone method for total body irradiation calculations to compute the proper dose received by the patient and determine the lung shield thickness. There are three main user-friendly interfaces in the application. The first one allows the user to upload the TBI topography and estimate the distances needed for TBI calculations. The second one enables the user to count the number of beam zones needed for each point and estimate the effective area (Aeff) for each level. The third interface estimates the velocity required to deliver the relative dose depending on patient separation, Monitor Units (MU), couch speed and travel distance. It allows the user to compute the required lung shield thickness, read any patient's CT DICOM file and acquire dose in any distinct location using machine learning model to predict the dose.ResultsThe TBICR software has been successfully validated by reproducing all of the manual calculations in an exact and timely manner. TBICR generated more accurate results and confirmed the absorbed dose to patient through measurements on Anderson phantom.ConclusionsA computer program for the calculation of total body irradiation (TBI) is described in full. The dose received at each point on the patient, the calculation of lung shield and the determination of the velocity and time required for the couch movement are all made possible using the software. The ease of use, precision, data storage and printing are some important features of the present software.  相似文献   
9.
《Digestive and liver disease》2022,54(11):1486-1493
BackgroundCold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.AimsWe aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.MethodsPubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.ResultsA total of 10 studies consisting of 1727 SSPs (range, 10–40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10–19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10–19 mm compared with those ≥20 mm (3.1% vs. 4.7%).ConclusionCSP was an effective and safe technique for removing SSPs ≥ 10 mm.  相似文献   
10.
BackgroundDilated cardiomyopathy (DCM) is a well described entity for heart failure (HF) with reduced left ventricular ejection fraction (LVEF). Recently, drugs and other substance of abuse have been recognised as potential triggers for DCM. The aim of this study was to assess the survival in patients ≤ 65 years of age with toxic cardiomyopathy (TCM). Left ventricular remodelling and the potential usefulness of left ventricular assist devices (LVADs) was also assessed.MethodsThis was a single-centre retrospective study from January 2003 to August 2019 of 553 patients ≤ 65 years old with LVEF < 40% at a tertiary-care cardiology centre.ResultsA total of 201 patients (36%) had a diagnosis of idiopathic DCM. Further analysis identified 38 patients (19%) for which a TCM was the most likely etiology (amphetamine [50%], cocaine [37%], anabolic steroids [8%], and energy drinks [5%]). Despite a mean LVEF of 17 ± 8% at presentation, most patients (n = 27; 71%) had event-free survival with guideline-directed medical therapy, and 61% (n = 23) recovered an LVEF ≥ 40% after a median follow-up of 21 ± 23 months. Seven patients (18%) required an LVAD and 1 patient (3%) a transplantation. All LVADs were explanted or decommissioned after partial or complete LVEF recovery after a median support time of 11 ± 4 months.ConclusionsTCM induced by substance abuse is a frequent cause of HF, accounting for almost 20% of patients ≤ 65 years of age with DCM of unknown etiology. Treatment must be tailored on an individual basis. Mechanical circulatory support demonstrated its usefulness in carefully selected patients.  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