全文获取类型
收费全文 | 97899篇 |
免费 | 4703篇 |
国内免费 | 1463篇 |
专业分类
耳鼻咽喉 | 533篇 |
儿科学 | 1508篇 |
妇产科学 | 1020篇 |
基础医学 | 11359篇 |
口腔科学 | 3994篇 |
临床医学 | 9024篇 |
内科学 | 20478篇 |
皮肤病学 | 1917篇 |
神经病学 | 6847篇 |
特种医学 | 2552篇 |
外国民族医学 | 7篇 |
外科学 | 14485篇 |
综合类 | 7355篇 |
现状与发展 | 7篇 |
一般理论 | 5篇 |
预防医学 | 7304篇 |
眼科学 | 1712篇 |
药学 | 6909篇 |
23篇 | |
中国医学 | 3403篇 |
肿瘤学 | 3623篇 |
出版年
2023年 | 1335篇 |
2022年 | 2237篇 |
2021年 | 3775篇 |
2020年 | 2760篇 |
2019年 | 6764篇 |
2018年 | 6911篇 |
2017年 | 4524篇 |
2016年 | 1877篇 |
2015年 | 1847篇 |
2014年 | 3454篇 |
2013年 | 3779篇 |
2012年 | 2643篇 |
2011年 | 2996篇 |
2010年 | 2554篇 |
2009年 | 2220篇 |
2008年 | 2315篇 |
2007年 | 2304篇 |
2006年 | 1999篇 |
2005年 | 1803篇 |
2004年 | 1544篇 |
2003年 | 1608篇 |
2002年 | 1215篇 |
2001年 | 1227篇 |
2000年 | 1066篇 |
1999年 | 978篇 |
1998年 | 804篇 |
1997年 | 805篇 |
1996年 | 669篇 |
1995年 | 683篇 |
1994年 | 620篇 |
1993年 | 512篇 |
1992年 | 478篇 |
1991年 | 437篇 |
1990年 | 371篇 |
1989年 | 338篇 |
1988年 | 334篇 |
1987年 | 278篇 |
1985年 | 3124篇 |
1984年 | 3637篇 |
1983年 | 3025篇 |
1982年 | 3525篇 |
1981年 | 3195篇 |
1980年 | 2635篇 |
1979年 | 2580篇 |
1978年 | 2103篇 |
1977年 | 1587篇 |
1976年 | 2034篇 |
1975年 | 1527篇 |
1974年 | 1333篇 |
1973年 | 1279篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
A. Montalto V. Piazza F. Albi R. Gherli C. Contento A. Palermo F. Musumeci 《Transplantation proceedings》2019,51(1):206-209
Background
Pump speed optimization in patients implanted with a ventricular assist device represents a major challenge during the follow-up period. We present our findings on whether combined invasive hemodynamic ramp tests and cardiopulmonary exercise testing (CPX) can help optimize patient management.Methods
Eighteen patients implanted with a HeartMate 3 (HM3) device underwent ramp tests with right heart catheterization (including central venous pressure [CVP], pulmonary artery pressure, pulmonary capillary wedge pressure [PCWP], and blood pressure) and echocardiography. Data were recorded at up to 4 speed settings. Speed changes were in steps of 200 revolutions/min (rpm). Evaluation of functional capacity by CPX was conducted according to the modified Bruce protocol.Results
Only 30% of patients had normal PCWPs at their original rpm settings. In going from lowest to highest speeds, cardiac output improved by 0.25 ± 0.35 L/min/step (total change, 1.28 ± 0.3 L/min), and PCWP decreased by 1.9 ± 0.73 mm Hg/step (total change, 6 ± 1.6 mm Hg). CVP and systolic blood pressure did not change significantly with rpm. The rpm assessment was adjusted based on test results to achieve CVPs and PCWPs as close to normal limits as possible, which was feasible in all patients. On CPX, all patients demonstrated good performance (peak VO2, 16.8 ± 3.5 mL/kg/min).Conclusion
Hemodynamic ramp testing provides an objective means of optimizing rpm, and has the potential to provide good exercise tolerance. 相似文献63.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。 相似文献
64.
Flavia Temperilli Aldona Rina Isabella Massimi Anna Lisa Montemari Maria Luisa Guarino Alessandra Zicari 《Platelets》2015,26(8):783-787
Serum thromboxane-B2 (TxB2), together with arachidonic acid (AA)-induced platelet aggregation, are, at the moment, the most used tests to identify patients displaying high on-aspirin treatment platelet reactivity (HAPR). Both tests are specific for aspirin action on cyclooxygenase-1. While the correlation between serum TxB2 assay and clinical outcome is established, data are conflicting with regard to aspirin treatment and a possible association with AA-stimulated platelet markers and clinical outcome. To understand such discrepancy, we performed a retrospective study to compare both assays. We collected data from 132 patients receiving a daily dose of aspirin (100?mg/day) and data from 48 patients receiving aspirin on alternate days. All Patients who received a daily dose of aspirin were studied for AA-induced platelet aggregation together with serum TxB2 levels and AA-induced TxB2 formation was also studied in 71 patients out of entire population. Consistent with recommendations in the literature, we defined HAPR by setting a cut-off point at 3.1?ng/ml for serum levels of thromboxane B2 and 20% for AA-induced platelet aggregation. According to this cut-off point, we divided our overall population into two groups: (1) TxB2?<?3.1?ng/ml and (2) TxB2?>?3.1?ng/ml. We found low agreement between such tests to identify patients displaying HAPR. Our results show that AA-induced platelet aggregation >20% identify a smaller number of HAPR patients in comparison with TxB2. A good correlation between serum TxB2 and arachidonic acid-induced TxB2 production was found (r?=?0.76619). 相似文献
65.
《Clinical gastroenterology and hepatology》2022,20(8):1776-1783.e4
- Download : Download high-res image (187KB)
- Download : Download full-size image
66.
67.
Yolanda Carrascal PhD Gregorio Laguna PhD Miriam Blanco MD Bárbara Segura MD Iciar Martínez-Almeida MD 《Journal of cardiac surgery》2020,35(2):457-459
Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries. 相似文献
68.
69.
70.