全文获取类型
收费全文 | 7528篇 |
免费 | 645篇 |
国内免费 | 163篇 |
专业分类
儿科学 | 354篇 |
妇产科学 | 48篇 |
基础医学 | 626篇 |
口腔科学 | 3篇 |
临床医学 | 1074篇 |
内科学 | 3947篇 |
皮肤病学 | 14篇 |
神经病学 | 125篇 |
特种医学 | 235篇 |
外科学 | 252篇 |
综合类 | 935篇 |
现状与发展 | 1篇 |
预防医学 | 110篇 |
眼科学 | 2篇 |
药学 | 412篇 |
3篇 | |
中国医学 | 179篇 |
肿瘤学 | 16篇 |
出版年
2024年 | 14篇 |
2023年 | 131篇 |
2022年 | 229篇 |
2021年 | 334篇 |
2020年 | 320篇 |
2019年 | 362篇 |
2018年 | 336篇 |
2017年 | 250篇 |
2016年 | 234篇 |
2015年 | 260篇 |
2014年 | 593篇 |
2013年 | 551篇 |
2012年 | 346篇 |
2011年 | 426篇 |
2010年 | 342篇 |
2009年 | 354篇 |
2008年 | 398篇 |
2007年 | 349篇 |
2006年 | 282篇 |
2005年 | 288篇 |
2004年 | 224篇 |
2003年 | 203篇 |
2002年 | 165篇 |
2001年 | 160篇 |
2000年 | 144篇 |
1999年 | 145篇 |
1998年 | 109篇 |
1997年 | 103篇 |
1996年 | 83篇 |
1995年 | 70篇 |
1994年 | 60篇 |
1993年 | 65篇 |
1992年 | 51篇 |
1991年 | 41篇 |
1990年 | 51篇 |
1989年 | 34篇 |
1988年 | 35篇 |
1987年 | 41篇 |
1986年 | 25篇 |
1985年 | 27篇 |
1984年 | 24篇 |
1983年 | 17篇 |
1982年 | 15篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1979年 | 5篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1975年 | 2篇 |
1974年 | 2篇 |
排序方式: 共有8336条查询结果,搜索用时 31 毫秒
101.
《JACC: Cardiovascular Imaging》2019,12(9):1769-1779
ObjectivesThis study sought to evaluate the prognostic value of cardiac magnetic resonance (CMR)-derived mitral annular plane systolic excursion (MAPSE) in a large multicenter population of patients with hypertension.BackgroundIn patients with hypertension, cardiac abnormalities are powerful predictors of adverse outcomes. Long-axis mitral annular movement plays a fundamental role in cardiac mechanics and is an early marker for a number of pathological processes. Given the adverse consequences of cardiac involvement in hypertension, the authors hypothesized that lateral MAPSE may provide incremental prognostic information in these patients.MethodsConsecutive patients with hypertension and a clinical indication for CMR at 4 U.S. medical centers were included in this study (n = 1,735). Lateral MAPSE was measured in the 4-chamber cine view. The primary endpoint was all-cause death. Cox proportional hazards regression modeling was used to examine the association between lateral MAPSE and death. The incremental prognostic value of lateral MAPSE was assessed in nested models.ResultsOver a median follow-up period of 5.1 years, 235 patients died. By Kaplan-Meier analysis, risk of death was significantly higher in patients with a lateral MAPSE < median (10 mm) (log-rank; p < 0.0001). Lateral MAPSE was associated with risk of death after adjustment for clinical and imaging risk factors (hazard ratio [HR]: 1.402-per-millimeter decrease; p < 0.001). Addition of lateral MAPSE in this model resulted in significant improvement in the C-statistic (0.735 to 0.815; p < 0.0001). Continuous net reclassification improvement was 0.739 (95% confidence interval: 0.601 to 0.902). Lateral MAPSE remained significantly associated with death even after adjustment for feature tracking global longitudinal strain (HR: 1.192-per-millimeter decrease; p < 0.001). Lateral MAPSE was independently associated with death among the subgroups of patients with preserved ejection fraction (HR = 1.339; p < 0.001) and in those without history of myocardial infarction (HR: 1.390; p < 0.001).ConclusionsCMR-derived lateral MAPSE is a powerful, independent predictor of mortality in patients with hypertension and a clinical indication for CMR, incremental to common clinical and CMR risk factors. These findings may suggest a role for CMR-derived lateral MAPSE in identifying hypertensive patients at highest risk of death. 相似文献
102.
103.
《Revista portuguesa de cardiologia》2019,38(7):473-480
IntroductionIn obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA) can lead to gradient reduction and symptom improvement. We aimed to assess the efficacy and safety of ASA in a long-term outcome study.MethodsWe analyzed patients who underwent ASA over a seven-year period in a tertiary center. The primary echocardiographic endpoint was >50% reduction in left ventricular outflow tract (LVOT) gradient within a year of the procedure. The primary clinical endpoints were improvement in functional capacity and a combined endpoint of cardiac death and rehospitalization for cardiac cause. The follow-up period was 4.17±2.13 years.ResultsA total of 80 patients, mean age 63.9±12.3 years, 30.0% male, were analyzed. Baseline LVOT gradient was 96.3±34.6 mmHg and interventricular septal thickness was 21.6±3.1 mm. Minor complications were observed in 6.3% and major complications in 2.5%, and 8.8% received a permanent pacemaker.The primary echocardiographic endpoint was achieved by 85.7%. At three-month follow-up, LVOT gradient was 25.8±26.0 mmHg in the successful procedure group, compared to 69.2±35.6 mmHg in the other patients (p=0.001). At six months, LVOT gradient was 27.1±27.4 vs. 58.2±16.6 mmHg (p=0.024). Among 74 patients in NYHA class III/IV before the procedure, 57 (77%) improved to NHYA class I/II. The combined primary clinical endpoint (cardiac death and rehospitalization for cardiac cause) was observed in 27.5% (n=22). In the unsuccessful group, the combined endpoint was observed in 54.5%, compared to only 22.7% in the successful group. Only two patients died of cardiac causes.ConclusionASA is a safe procedure with a high success rate. Patients who achieved significant reductions in LVOT gradient suffered less cardiac death and rehospitalization for cardiac cause. 相似文献
104.
105.
《Journal of cardiac failure》2014,20(12):968-972
ObjectiveOur objective was to investigate whether dobutamine stress echocardiography (DSE) could induce abnormal cardiac function in takotsubo stress cardiomyopathy (TSC) patients in a stable condition after the acute attack.Methods and ResultsThis was a case-control study and a substudy of the Stockholm Myocardial Infarction With Normal Coronaries (SMINC) study. Twenty-two patients with a previous episode of TSC and 22 sex- and age-matched control subjects were recruited from the SMINC study and investigated with the use of DSE. All TSC patients had a previous normal cardiovascular magnetic resonance investigation. Tissue Doppler imaging–derived time phases of the cardiac cycle were recorded to calculate myocardial performance index (MPI) to assess ventricular function. Compared with control subjects at rest, TSC patients had a slightly but significantly higher left ventricular MPI (LV-MPI; 0.53 vs 0.59; P = .01) and as a trend higher right ventricular MPI (0.38 vs 0.47; P = .08), although during DSE these variables did not differ significantly.ConclusionWe found no difference in standard diastolic parameters between TSC and control subjects, but a significant higher value in LV-MPI in the TSC group at rest. However, no such difference could be demonstrated during DSE between the groups, indicating that vulnerability to sympathetic stimulation does not persist in TSC patients. 相似文献
106.
《Journal of cardiac failure》2014,20(3):207-211
Cardiac transplantation is severely restricted by donor availability. Left ventricular dysfunction due to neurogenic stress cardiomyopathy is often seen during donor evaluation and often presents a clinical dilemma for procurement. We report a case of a 23-year-old man with severe left ventricular dysfunction whose heart was successfully procured for transplantation. The brief case report is followed by an extensive review of neurogenic stress cardiomyopathy as well as donor evaluation for cardiac transplantation in the setting of such cardiomyopathy. 相似文献
107.
Outcome of patients with systemic light chain amyloidosis with concurrent renal and cardiac involvement 下载免费PDF全文
Talha Badar Amanda Megan Cornelison Nina D. Shah Qaiser Bashir Simrit Parmar Krina Patel Chitra Hosing Uday Popat Donna M. Weber Sheeba K. Thomas Jatin J. Shah Robert Z. Orlowski Richard E. Champlin Muzaffar H. Qazilbash 《European journal of haematology》2016,97(4):342-347
Cardiac involvement in systemic light chain amyloidosis (AL) is generally associated with a worse outcome, especially if other organs are also involved. We sought to determine whether concurrent cardiac and renal involvement were associated with a worse outcome than either organ alone. We identified 129 patients with AL, who received high‐dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto‐HCT) at our institution between 1997 and 2014. Ninety‐nine patients had either renal (group 1: n = 62, 62%), cardiac (group 2: n = 20, 20%), or both cardiac and renal (group 3: n = 17, 17%) involvement. The overall hematological response rate (CR+VGPR+PR) post‐auto‐HCT in groups 1, 2, and 3 was 69%, 74% and 82%, respectively (P = 0.62). Overall, organ response in groups 1, 2, and 3 was 39%, 42%, and 70%, respectively. The median PFS from auto‐HCT in groups 1, 2, and 3 was not reached (NR), 13.3 and 21 months, respectively (P = 0.02). The median OS in groups 1, 2, and 3 was 120, 46, and 60 months, respectively (P = 0.1). In conclusion, median PFS and OS in patients with concurrent cardiac and renal AL were comparable to patients with cardiac AL only, but worse than patients with renal AL. 相似文献
108.
109.
110.
Zhaohui Wang Yu-Hua Liao Jing Yuan Jing-Hui Zhang Zhong-Ping Liu Ji-Hua Dong 《Autoimmunity》2013,46(6):455-460
T-cell immune abnormality in patients of dilated cardiomyopathy has been intensively studied over the past 10 years. In this study, we aim to focus on the molecular mechanism of T-cells in autoimmune cardiomyopathy mouse model by detecting the expression of three T-cell signaling molecules. Balb/C mice (n = 12) were immunized with the peptides derived from human ADP/ATP carrier on the 1st, 14th, 28th, 49th and 79th days, and half of them were also injected with anti-L3T4 McAb on the ? 1st, 0 and 1st days. The sham-immunized mice were taken as the controls (n = 6). The main result shows that the antibody response of IgG subclasses such as IgG1, IgG2b and IgG3 were definitely blocked except IgG2a in CD4+ cell-depleted Balb/C mice. In addition, the average mRNA expression of p56lck, p59fyn and zap-70 were all found to be dramatically higher in the mice immunized with only ADP/ATP carrier peptides than in the control-group. At meantime, reduced levels of the protein kinases p56lck, p59fyn and zap-70 were clearly observed in anti-CD4 McAb immunized group compared with DCM group. We propose that the proliferation of T-cells was significantly inhibited in anti-CD4 treated mice and CD4+ T-cells may play a critical role in ADP/ATP carrier caused mouse DCM. 相似文献