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71.
射频导管消融治疗室上性心动过速对心率变异性的影响   总被引:1,自引:0,他引:1  
目的:探讨射频导管消融对心脏自主神经系统功能的影响。方法:对53例室上性心动过速患者采用时域、频域法对比分析射频导管消融前后心率变异性。结果:射频导管消融术后平均心率、最小心率、低频与高频的比值上升,24小时平均心率的标准差,心率变异性指数、变异系数、24小时RR间期直方图1/2高度时的宽度、24小时RR间期直方图1/10高度时的宽度、总频谱,低频成份和高频成份均降低。结论:射频导管消融术后迷走神经和交感神经张力均降低,但主要影响的是迷走神经张力,从而表现为心率变异性的降低。  相似文献   
72.
王劲风  汪祥海  蔚有权  刘文洁  杨浩 《安徽医药》2015,36(10):1194-1196
目的 探讨Carto 3三维电生理导航系统指导消融频发性室性早搏(PVC)的临床疗效,以及射频消融术(RFCA)前后血浆氨基末端B型利钠肽(NT-pro BNP)、心脏结构功能的变化。方法 选取2011年至2013年47例频发室性早搏患者行射频消融治疗的患者为病例组,根据标测系统的不同,分为传统组(n=17)和三维组(n=30)。观察比较两组手术时间、X线曝光时间、放电次数及手术即刻成功率、远期成功率。同时监测所有病例行导管消融前及消融3个月后的NT-pro BNP、左室射血分数(LVEF)及左室舒张末期内径(LVEDd)值,另选取51例健康体检者为对照组。结果 三维组在手术时间、X线曝光时间、消融放电次数上明显优于传统组,且差异有统计学意义(P<0.05)。两组即刻成功率(82.35% vs 93.33%)、远期成功率(76.47% vs 86.67%)相近,差异无统计学意义(P>0.05)。对照组、病例组术前、病例组术后3个月NT-pro BNP浓度、LVEDd以及LVEF值比较,差异均无统计学意义(P>0.05)。结论 较二维影像,在Carto 3三维电生理导航系统下行射频消融治疗频发性室性早搏具有较高的即刻及远期成功率,且安全、有效。  相似文献   
73.
Intractable cancer pain not amenable to standard oral or parenteral analgesics is a horrifying truth in 10–15% of patients. Interventional pain management techniques are an indispensable arsenal in pain physician''s armamentarium for severe, intractable pain and can be broadly classified into neuroablative and neuromodulation techniques. An array of neurolytic techniques (chemical, thermal, or surgical) can be employed for ablation of individual nerve fibers, plexuses, or intrathecalneurolysis in patients with resistant pain and short life-expectancy. Neuraxial administration of drugs and spinal cord stimulation to modulate or alter the pain perception constitutes the most frequently employed neuromodulation techniques. Lately, there is a rising call for early introduction of interventional techniques in carefully selected patients simultaneously or even before starting strong opioids. After decades of empirical use, it is the need of the hour to head towards professionalism and standardization in order to secure credibility of specialization and those practicing it. Even though the interventional management has found a definite place in cancer pain, there is a dearth of evidence-based practice guidelines for interventional therapies in cancer pain. This may be because of paucity of good quality randomized controlled trials (RCTs) evaluating their safety and efficacy in cancer pain. Laying standardized guidelines based on existing and emerging evidence will act as a foundation step towards strengthening, credentialing, and dissemination of the specialty of interventional cancer pain management. This will also ensure an improved decision-making and quality of life (QoL) of the suffering patients.  相似文献   
74.
Background: Catheter ablation of the atrioventricular (AV) junction using stored direct current (DC) energy from a standard DC Cardioverter defibrillator was first reported in 1982. Since then many patients have been treated using this procedure for refractory supraventricular arrhythmias, usually atrial fibrillation and flutter. Undesirable thermal effects such as barotrauma and arcing are largely responsible for complications associated with the use of DC energy. This report details our experience of catheter ablation of the AV junction using radiofrequency (RF) energy in a series of 30 consecutive patients. Methods: RF ablations were performed using steerable Mansfield (Webster Laboratories) 4 mm tipped electrodes and locally assembled RF energy delivery system. Results: The procedure was successful in 27/30 (90%) patients using RF energy, while three patients required DC energy to achieve successful AV junction ablation. General anaesthesia was required in nine patients, six of whom required this for cardioversion to sinus rhythm so that an adequate His Bundle spike could be recorded and three for DC ablation. Dual chamber permanent pacemakers with automatic mode switching were implanted in four patients who had paroxysmal atrial fibrillation or flutter and the remainder had ventricular rate responsive pacemakers. Conclusions: In patients with drug refractory paroxysmal atrial fibrillation and flutter and in patients with established atrial fibrillation where control of the ventricular rate is difficult, catheter ablation of the AV junction using RF energy is a safe and effective procedure with a high success rate.  相似文献   
75.
Background A better understanding of the mechanisms of recurrent atrial fibrillation (AF) after radiofrequency ablation of complex, fractionated atrial electrograms (CFAEs) may be helpful for refining AF ablation strategies. Methods and results Electrogram-guided ablation (EGA) was repeated in 30 consecutive patients (mean age = 59 ± 8 years) for recurrent paroxysmal AF, 10 ± 4 months after the first ablation. During the first procedure, CFAEs were targeted without isolating all pulmonary veins (PVs). During repeat ablation, all PVs and the superior vena cava (SVC) were mapped with a circular catheter and the left atrium was mapped for CFAEs. EGA was performed until AF was rendered noninducible or all identified CFAEs were eliminated. During repeat ablation, ≥1 PV tachycardia was found in 83 PVs in 29 of the 30 patients (97%). Among these 83 PVs, 63 (76%) had not been completely isolated previously. During repeat ablation, drivers originating in a PV or PV antrum were identified only after infusion of isoproterenol (20 μg/min) in 12 patients (40%). At 9 ± 4 months of follow-up after the repeat ablation procedure, 21 of the 30 patients (70%) were free from recurrent AF and flutter without antiarrhythmic drugs. Conclusions Recurrence of AF after EGA is usually due to PV tachycardias. Therefore, it may be preferable to systematically map and isolate all PVs during the first procedure. High-dose isoproterenol may be helpful to identify AF drivers.  相似文献   
76.
目的 探讨食管内镜下射频消融术(radiofrequency ablation,RFA)后患者发热的独立危险因素。方法 2016年1月—2021年4月,因早期食管癌就诊于长海医院消化内科,且病变范围超过食管3/4环周的51例病例纳入病例对照研究。患者均行RFA治疗,按术后是否发热分成发热组(n=15)和未发热组(n=36),主要收集患者一般情况、消化道肿瘤家族史、病变长度、病变范围、消融能量和消融次数用于单因素分析,其中P<0.1的变量再进一步纳入多因素Logistic回归分析探究RFA术后发热的独立危险因素。结果 单因素分析发现,病变长度(t=-3.89,P<0.001)、病变范围(χ2=11.52,P=0.001)和消融能量(P=0.001)在2组间差异有统计学意义。Pearson相关性显示,病变长度与病变环周长度存在明显正相关(r=0.71,P<0.001),而病变范围由病变环周长度决定,因此最终将病变长度和消融能量这两个变量纳入Logistic回归方程。Logistic回归分析结果显示,食管病变长度每增加1 cm,患者发生RFA术后发热的风险是前者的1.21倍(95%CI:1.01~1.43,P=0.037);术中使用12 J消融能量者,发生RFA术后发热的风险是使用10 J消融能量者的0.43倍(95%CI:0.22~0.85,P=0.015)。结论 病变长度和消融能量是导致食管RFA术后发热的独立危险因素。长节段早期食管癌者更易发生RFA术后发热,术中使用低消融能量者更易发生RFA术后发热。  相似文献   
77.
目的研究不完全射频消融(RFA)治疗对兔VX2肝癌模MMP-9蛋白表达的影响。 方法建立新西兰白兔的VX2肝癌模型,将30只兔VX2肝癌模型分为2组,即对照组和实验组,每组15只,对照组只做开关腹,而不进行RFA;实验组进行开腹消融,消融范围为肿瘤组织的75%;在实验组中设立RFA后快速进展亚组,定义为实验结束时肿瘤的倍增率大于对照组。对比其RFA后的VX2肝癌的体积变化、残留VX2肝癌基质金属蛋白酶-9(MMP-9)的表达情况。 结果对照组和实验组治疗后肿瘤体积分别为(7 862±1 304)mm3和(6 996±709)mm3,肿瘤的倍增率分别为(291±49)和(232±16),差异有统计学意义(P < 0.05)。对照组和实验组MMP-9阳性表达率为52.1%和46.3%,差异均有统计学意义(P < 0.05);实验组中3只实验兔肿瘤倍增率及MMP-9表达率明显高于实验组,属于RF后快速进展亚组,差异有统计学意义(P < 0.05)。 结论部分性消融对大多数肝细胞癌具有一定疗效,但对于少数肿瘤可能加速其生长,而MMP-9的过表达可能是促进残留癌快速进展的原因。  相似文献   
78.
1995年前射频消融(RFCA)治疗各类心动过速120例,总成功率97.5%。采用心电图、动态心电图或经食管心房调搏检查保持随访的共108例,随访时间6~35个月,复发3例,心动过速复发率2.8%。复发的3例经分析与消融放电时间太短、未能造成稳定性损伤有关。59例术后1~3个月二维超声心动图复查未发现因RFCA而造成心脏结构、舒缩功能和射血分数等改变。  相似文献   
79.
经主动脉窦途径射频消融心动过速临床研究   总被引:1,自引:0,他引:1  
目的:探讨经主动脉窦途径导管射频消融治愈的快速性心律失常患者的心电图特点及射频消融情况.方法:回顾性分析17例室性心动过速/室性期前收缩、前间隔房性心动过速及前间隔旁路等该类患者的体表心电图、及消融成功时靶点电图等心电生理学特征.结果:经主动脉窦途径导管射频消融治愈室性心动过速/室性期前收缩12例,其中起源于左冠状动脉窦(左冠窦)10例、右冠状动脉窦(右冠窦)2例;源于无冠状动脉窦(无冠窦)的局灶性前间隔房性心动过速3例及前间隔旁路2例.室性心动过速/室性期前收缩心电图特点:Ⅱ、Ⅲ和aVF导联为高大R波,胸导联R波移行较早,V1导联r/S波振幅比≥30%,r波时限(82.2±16.4)ms,V1导联中r/QRS波时限比≥50%,V5、V6导联为高振幅R波、无s波.有效消融靶点心内电图示心室波明显比体表心电图QRS波提前(35.2±21.6)ms.前间隔房性心动过速均能被心房刺激反复诱发和终止,其心电图特点:房性心动过速时P波间期明显窄于窦律时P波间期,Ⅰ、aVL导联P波正向,Ⅱ、Ⅲ和aVF导联P呈负正双向.在心房标测中提示最早的心房激动在希氏(His)束区,但在主动脉无冠窦内标测的心房激动较His束区的心房波提前,其解剖定位于His束上后方,消融靶点无His束电位.前间隔旁路心电图示:窦性心律时呈窄QRS波形,未见预激波,心动过速呈窄QRS形,在无冠窦内记录到最早心房激动点,且无His束电位.17例均消融成功.结论:源于主动脉窦内的室性心动过速/室性期前收缩、前间隔房性心动过速和前间隔旁路具有相对的心内电生理学特征,常规心内膜途径消融困难时应该考虑从主动脉窦途径标测消融策略,把握消融导管与冠状动脉的关系,导管消融治疗安全而有效.  相似文献   
80.
Overall, 133 patients underwent 170 procedures for the treatment of persistent ATa following an index cryoballoon pulmonary vein isolation (n = 715). After all the procedures, > 90% of the patients had a roof line, a mitral isthmus and/or septal line, and a cavotricuspid isthmus line. Ninety-two patients (69.2%) were in sinus rhythm after a median of 36 months since the index cryoballoon PVI. ATa: atrial tachyarrhythmia; cryo: cryoballoon; CTI: cavotricuspid isthmus; LSPV: left superior pulmonary vein; LIPV: left inferior pulmonary vein; PVI: pulmonary vein isolation; RF: radiofrequency; RSPV: right superior pulmonary vein; RIPV: right inferior pulmonary vein.
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