全文获取类型
收费全文 | 18143篇 |
免费 | 1313篇 |
国内免费 | 320篇 |
专业分类
耳鼻咽喉 | 47篇 |
儿科学 | 48篇 |
妇产科学 | 22篇 |
基础医学 | 1059篇 |
口腔科学 | 25篇 |
临床医学 | 3257篇 |
内科学 | 9872篇 |
皮肤病学 | 24篇 |
神经病学 | 792篇 |
特种医学 | 235篇 |
外科学 | 835篇 |
综合类 | 1815篇 |
预防医学 | 351篇 |
眼科学 | 20篇 |
药学 | 1131篇 |
9篇 | |
中国医学 | 209篇 |
肿瘤学 | 25篇 |
出版年
2024年 | 24篇 |
2023年 | 370篇 |
2022年 | 425篇 |
2021年 | 919篇 |
2020年 | 855篇 |
2019年 | 836篇 |
2018年 | 766篇 |
2017年 | 598篇 |
2016年 | 577篇 |
2015年 | 592篇 |
2014年 | 1288篇 |
2013年 | 1301篇 |
2012年 | 880篇 |
2011年 | 907篇 |
2010年 | 788篇 |
2009年 | 865篇 |
2008年 | 913篇 |
2007年 | 910篇 |
2006年 | 829篇 |
2005年 | 687篇 |
2004年 | 566篇 |
2003年 | 572篇 |
2002年 | 409篇 |
2001年 | 340篇 |
2000年 | 309篇 |
1999年 | 274篇 |
1998年 | 230篇 |
1997年 | 195篇 |
1996年 | 143篇 |
1995年 | 151篇 |
1994年 | 125篇 |
1993年 | 109篇 |
1992年 | 117篇 |
1991年 | 94篇 |
1990年 | 100篇 |
1989年 | 79篇 |
1988年 | 67篇 |
1987年 | 63篇 |
1986年 | 69篇 |
1985年 | 57篇 |
1984年 | 60篇 |
1983年 | 41篇 |
1982年 | 42篇 |
1981年 | 32篇 |
1980年 | 28篇 |
1979年 | 26篇 |
1978年 | 30篇 |
1977年 | 19篇 |
1976年 | 28篇 |
1975年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
Motohiko Kimura Toshifumi Sugiura Yoshihito Fukui Morio Togawa Yukio Harada† 《Artificial organs》1990,14(5):390-391
Carbon fibers with fibrin glue were used as electrodes for diaphragm pacing. The electrodes were applied to three mongrel dogs and the effectiveness was tested. The carbon leads were glued to phrenic nerves by means of the fibrinogen and thrombin bilaterally. The tidal volumes and threshold current level for stimulation were measured at various time up to 9 weeks after implantation. Effective contraction of diaphragm were observed for 9 weeks. By using this electrode, the exfoliation of the nerve is not necessary, the nerve can be maintained in an intact state, and the risk of the implanting operation can be minimized. 相似文献
43.
44.
目的 探讨急性心肌梗死(AMI)病人不同时期发生房颤(AF)的临床特点、治疗及预后。方法 采用非创伤性12导联心电图及心电监测法,监测460例AMI病人AF的发生率、原因、药物治疗反应及预后。其中40例病人发生AF,按发生时期分为两组:(1)早发组24例为发病24小时内出现AF;(2)晚发组16例为发病24小时后出现AF。结果 460例AMI病人中,发生AF40例(8.7%)。AF病人的住院病死率、心力衰竭、恶性心律失常发生率比无AF病人高(P<0.05)。其中,晚期AF组病人住院病死率比早期AF组病人增加(P<0.05)。结论 AMI病人并发AF,尤其并发晚发AF,提示病情重,预后不良。 相似文献
45.
马建国 《山东医学高等专科学校学报》2004,26(2):137-139
目的探讨二尖瓣狭窄合并心房纤颤患者在球囊二尖瓣扩张后,转复心房纤颤的临床效果及影响心房纤颤转复后窦性心律维持的相关因素.方法 206例二尖瓣狭窄合并心房纤颤患者在球囊扩张术后,采用口服胺碘酮及电复律治疗心房纤颤,对复律成功的患者给予小剂量胺碘酮维持窦性心律并随访1年.结果服用胺碘酮者58例,17例转复成功(29.3%);189例行电转复,178例转复成功(94.2%),电转复成功率明显高于胺碘酮转复(P<0.01).心房纤颤复发组与保持窦性心律组相比,左心房内径明显扩大(P<0.01),心房纤颤持续时间明显长(P<0.01),中度二尖瓣关闭不全人数的比率明显高(P<0.05).随访1年,有45例患者心房纤颤复发.影响心房纤颤转复后维持窦性心律的相关因素有左心房内径扩大、心房纤颤持续时间长及明显的二尖瓣关闭不全.结论对左心房内径明显扩大、心房纤颤持续时间过长及有明显的二尖瓣关闭不全的患者,在选择心房纤颤转复时应慎重. 相似文献
46.
对医疗设备电气控制线路的各种隔离进行了详尽的分析讨论,提出了抑制干扰而采取的电气隔离的技术措施,从而保证医疗设备的正常工作。 相似文献
47.
A recent series of randomized prospective clinical trials that compared rate control with rhythm control in patients with atrial fibrillation (AF) found no significant difference in primary outcome between the two strategies. However, these trials lacked clear criteria for defining "successful" rate or rhythm control. Various measures have been used to gauge the success of antiarrhythmic drug therapy, including time to first recurrence of AF, any AF recurrence, AF burden, and a reduction in symptoms. Determining the success of antiarrhythmic therapy can be relatively straightforward by using how patients feel during therapy as a key endpoint. Most patients are satisfied with a major reduction in symptomatic AF episodes and can live comfortably with occasional episodes of AF. For those who are bothered by even infrequent, brief AF episodes, a treatment regimen that eliminates nearly all AF recurrences is required, although often hard to achieve. Catheter ablation may be necessary to achieve a successful outcome in these patients. Suppression of AF in a patient at high risk of stroke does not, however, remove the need for concomitant warfarin therapy. The endpoints of ventricular rate control are not clear, and the recently published rhythm versus rate control trials lacked standard criteria for judging acceptable rate control. One relatively simple method is to try and achieve a 24-hour heart rate that mimics expected normal sinus rhythm. It is important to achieve good rate control to minimize symptoms and the risk of tachycardia-mediated cardiomyopathy. 相似文献
48.
心房颤动外科手术的发展与评价 总被引:1,自引:0,他引:1
汪曾炜 《海军军医大学学报》2005,26(2):124-126
随着电生理学对房颤机制的深入研究和新型标测技术消融能源的发展,房颤的外科治疗不断取得新的突破.由Cox迷宫手术的复杂术式逐渐向左迷宫、放射迷宫衍变.减少创伤提高治愈率,成为房颤外科治疗不断追求的新目标.本文概述了房颤外科治疗的各种术式设计原理和房颤根治术新消融技术的应用及其疗效评价. 相似文献
49.
Hirotsugu Yamada MD PhD Zoran B. Popovic MD PhD David O. Martin MD MPH Kenneth C. Civello MD MPH Don W. Wallick PhD 《Heart rhythm》2006,3(6):722-727
BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied. 相似文献
50.
目的 观察可达龙 (胺碘酮 )加小剂量地高辛对部分经冠脉造影确诊的高血压性心脏病 (高心病 )与冠心病患者心房颤动 (房颤 )转复窦性心律的可能与安全性。方法 符合入选条件、住院连服 2周可达龙 (0 .2g,3/d)未复律的高心病、冠心病并房颤患者 32例 ,加服地高辛 0 .1 2 5g ,2 /d ,2周后为观察终点 ,判断其房颤转复成功率与用药安全性 ;并随访半年 ,观察房颤复发率。结果 32例中转复窦性心律 2 3例 ,转复率 71 .9% ,平均转复时间 (7± 2 )d ,无一例出现药物副作用 ;随访半年 ,复发 6例 ,复发率占复律者的 2 6 .1 %。结论 可达龙加小剂量地高辛对高心病、冠心病患者的房颤转复窦性心律 ,具有疗效较高 ,安全性与依从性好等优点 ,但仍有一定的复发率。 相似文献