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941.
目的 探讨重叠参考图像透视技术(Overlay Ref)对环肺静脉电隔离术治疗阵发性心房颤动(房颤)的影响.方法 入选194例阵发性房颤患者,随机分为Overlay Ref组(97例)及对照组(97例).Overlay Ref组使用Overlay Ref技术(将参考图像以反白的形式叠加于透视屏上)辅助环肺静脉电隔离术的操作.对照组常规方法完成环肺静脉电隔离术.比较两组的总消融手术时间、消融时间、X线曝光量、肺静脉隔离率及随访1年的成功率.结果 两组患者的基线临床特征差异无统计学意义.所有患者均接受了环肺静脉电隔离术.Overlay Ref组的消融时间〔(89±13) min对(102±22) min,P<0.01〕和总消融术时间[ (139±22) min对(162±31) min,P<0.01]均明显比对照组短.Oveday Ref组的X线曝光量[( 13531±283) mGy对(13123±369)mGy]稍大,但差异无统计学意义(P>0.05).两组的环肺静脉电隔离率(97.9%对96.9%,P=NS)及随访1年的成功率(84.5%对81.4%,P>0.05)差异也无统计学意义.结论 Overlay Ref技术可以易化环肺静脉电隔离术的操作,缩短房颤导管消融术的学习曲线.  相似文献   
942.
目的 评价以左心房-肺静脉电联系双向阻滞作为环肺静脉消融电隔离术终点对阵发性心房颤动(房颤)导管消融疗效的影响.方法 在76例阵发性房颤患者导管消融达到左心房-肺静脉传入阻滞后,分别于每根肺静脉内起搏评价肺静脉-左心房传导情况.据此分为双向阻滞组(传入与传出均阻滞)和传入阻滞组,随访观察房颤导管消融的临床疗效.结果 76例均完成导管消融术,306根肺静脉(2例患者存在右中肺静脉)均达到左心房-肺静脉电学传入阻滞之传统终点.18例消融术后左心房-肺静脉传导呈双向阻滞,58例仅传入阻滞.平均随访(6.85±1.08)个月,1次消融成功率为77.63%.其中,双向阻滞组为83.33%,传入阻滞组为75.86%,两组相比差异无统计学意义(P>0.05).术后房性心动过速发生率5.26%(4/76),无心脏压塞、脑栓塞、左心房食管瘘等并发症以及死亡发生.结论 以左心房-肺静脉传导双向阻滞为房颤导管消融终点治疗阵发性房颤的策略似乎临床疗效较好.  相似文献   
943.
目的:探讨冠状动脉搭桥手术患者术后应激性血糖与术前糖化血红蛋(HbA1c)的关系。方法:回顾分析96例无糖尿病史且行心脏冠状动脉搭桥手术患者,术前完善了口服葡萄糖耐量(OGTT)试验除外糖尿病,根据HbA1c值分为相对高糖化组(HbA1c≥6.0%)和对照组(HbA1c<6.0%),观察2组术前基线指标和术后应激性血糖有无差异及相关性。结果:高糖化组与对照组术前年龄(P=0.001)、体质量指数(BMI)(P=0.007)、腰臀比(WHR)(P=0.0001)、胰岛素抵抗(HOMA-IR)指数(P=0.001)以及术后应激性血糖(P=0.0001)差异均有统计学意义;高糖化组术后应激性高血糖患者明显多于对照组(P=0.001),线性回归分析显示术前HbA1c值和应激性血糖密切相关(R2=0.224)。结论:术前超质量或腹型肥胖尤其是年龄大者,即使无糖尿病也应测定HbA1c,如果HbA1c≥6.0%应积极防治术后应激性高血糖。  相似文献   
944.
目的:评价内窥镜下采集小腿大隐静脉,用于非体外循环冠状动脉搭桥术(off pump coronary artery bypass grafting,OPCABG)的临床效果。方法:选取OPCABG患者269例,根据小腿大隐静脉取材方式将患者分为,内窥镜血管采集(endoscopic vein harvesting,EVH)组和全程切开(open vein harvesting,OVH)组,比较两组取材时间、取材质量、切口并发症、围术期和术后近期随访时的临床效果及患者评价。结果:EVH组取材长度、血管质量和取材时间可满足冠状动脉搭桥手术需要。与OVH组相比,EVH组术后切口并发症发生率和下肢水肿发生率显著降低,且差异有统计学意义,但皮下组织瘀斑发生率较OVH组高。取材时间EVH组平均35 min,OVH组平均45 min,差异有统计学意义。远端吻合口数目EVH组3.2个/例,OVH组3.1个/例,差异无统计学意义。两组围术期心肌梗死发生率差异无统计学意义。本研究中,所有患者均痊愈出院,术后平均随访4~5个月,均无心绞痛再发。结论:CABG术中采取EVH取小腿大隐静脉的方法有效可行。其作为一种微创取血管的方法,取材质量良好、切口小、并发症更少,得到了医生和患者的认可。  相似文献   
945.
AIM: To compare the incidence of early portal or splenic vein thrombosis (PSVT) in patients treated with irregular and regular anticoagulantion after splenectomy with gastroesophageal devascularization.METHODS: We retrospectively analyzed 301 patients who underwent splenectomy with gastroesophageal devascularization for portal hypertension due to cirrhosis between April 2004 and July 2010. Patients were categorized into group A with irregular anticoagulation and group B with regular anticoagulation, respectively. Group A (153 patients) received anticoagulant monotherapy for an undesignated time period or with aspirin or warfarin without low-molecular-weight heparin (LMWH) irregularly. Group B (148 patients) received subcutaneous injection of LMWH routinely within the first 5 d after surgery, followed by oral warfarin and aspirin for one month regularly. The target prothrombin time/international normalized ratio (PT/INR) was 1.25-1.50. Platelet and PT/INR were monitored. Color Doppler imaging was performed to monitor PSVT as well as the effectiveness of thrombolytic therapy.RESULTS: The patients’ data were collected and analyzed retrospectively. Among the patients, 94 developed early postoperative mural PSVT, including 63 patients in group A (63/153, 41.17%) and 31 patients in group B (31/148, 20.94%). There were 50 (32.67%) patients in group A and 27 (18.24%) in group B with mural PSVT in the main trunk of portal vein. After the administration of thrombolytic, anticoagulant and anti-aggregation therapy, complete or partial thrombus dissolution achieved in 50 (79.37%) in group A and 26 (83.87%) in group B.CONCLUSION: Regular anticoagulation therapy can reduce the incidence of PSVT in patients who undergo splenectomy with gastroesophageal devascularization, and regular anticoagulant therapy is safer and more effective than irregular anticoagulant therapy. Early and timely thrombolytic therapy is imperative and feasible for the prevention of PSVT.  相似文献   
946.
目的:研究1个肝脏劈离成3个供肝单位的动物实验可行性.方法:普通级健康犬分成供体组(n=30,体质量20-25 kg)和受体组(n=30,体质量8-15kg),供受体随机配对.供体手术断离右外叶和右中叶、左中叶和方叶之间的2处肝组织桥,原位灌注后将左侧区、中央区和右侧区供肝各自的一级肝蒂在近主干处切断,移植物受体体质量比(graft-to-recipient weight ratio,GRWR)>1.0%且最接近1.5%的供肝入选为移植物,植入左侧区、中央区和右侧区供肝的受体分别分入A组、B组和C组.供肝背驮式植入受体,流出口和腔静脉壁端侧吻合,供肝一级肝蒂分别和受体门管三联的主干端端吻合.术后观察受体腹腔及胆汁引流,死亡后进行尸检,移植物取标本进行病理检查.结果:犬肝外观呈分叶状,深陷的叶间裂将各叶分隔开来,各叶间由较少的肝组织桥相连接,右外叶和右中叶间的肝桥组织较左中叶和方叶间的肝桥组织更薄更少,2处肝桥离断时均未发现有大的血管及胆管.门静脉主要分成左支、中支和右支;胆总管也由左、中及右肝管三支肝管汇合而成;肝动脉可存在变异;肝血液经由肝左、中、右3支静脉回流.3组供体的平均体质量、手术时间及失血量差异的比较无统计学意义.体内劈离技术全部得以完成,供肝无热缺血损伤.3组受体体质量、供肝质量和GRWR之间的差异均存在显著的统计学意义(P<0.01),但手术时间、无肝期、失血量及输血量间的差异无统计学意义(P>0.05).3组受体中无术中死亡者,30个供肝均成功植入,所有血管及胆道的吻合均不需要移植物间置,门静脉和动脉重建后均能排泌胆汁,各组新肝均无淤血、缺血区.3组受体存活时间分别为128.3 h±48.5 h、102.7 h±59.8 h和98.7 h±36.8 h,各组之间的差异无统计学意义(P=0.234).死亡后尸检均未发现有吻合口出血、血栓等外科技术性并发症者,移植物标本病理检查肝细胞无淤血肿胀和缺血坏死者.结论:此项动物实验证明:一个大受体的肝脏能劈离成3个部分,且每一部分都能作为独立完整的供肝移植给不同体质量的小受体.  相似文献   
947.
Modified Pulmonary Vein Isolation in AF Ablation. Introduction: Pulmonary vein isolation (PVI) is the primary ablation therapy in patients with atrial fibrillation (AF). We hypothesized that high dominant frequency (DF) sites (AF nests during sinus rhythm [SR]) adjacent to the PV ostia are associated with the atrial substrate that maintains AF, and PVI incorporating the high‐frequency AF nests may have a higher efficacy. Methods and Results: In a prospective and randomized comparison, 126 symptomatic paroxysmal AF patients that underwent PVI were enrolled. We compared the efficacy of a modified PVI (ablation line: 1.0–1.5 cm from the PV ostium with encircling the AF nests [spectral analysis with DF >70 Hz during SR, Group II]) versus the anatomy‐guided conventional PVI (Group I). In Group II, the DF value along the PV ostium was lower than 70 Hz after the PVI. The primary endpoint was the freedom from symptomatic atrial arrhythmias after a single procedure. We also followed the autonomic function by a time‐domain analysis of the heart rate variability. In both groups, AF nests were observed and electric isolation was successfully obtained in all patients. With a mean duration of 16 ± 6.1 months of follow‐up, Group II had a higher single procedure efficacy without drugs (78.7% vs 66.1%, log‐rank test: P = 0.02), and fewer repeat procedures (6.6% vs 23%; P = 0.04), as compared to Group I. Conclusion: PVI incorporating the high frequency AF nests adjacent to the PV ostia had a better single procedure efficacy. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1155–1162, November 2012)  相似文献   
948.
Pulmonary vein stenosis can complicate ablation procedures for atrial fibrillation and often presents with severe respiratory symptoms. Described in this case report is a 21-year-old male who underwent a bilateral surgical augmentation of the pulmonary veins for severe occlusive pulmonary vein stenosis. The occluded left lower and right upper lobe veins were surgically modified to regain flow to the left atrium. Follow-up computed tomogram imaging showed patency of the veins intervened upon and an exercise test demonstrated an oxygen saturation of 98% at peak stress.This case report marks the first-ever surgical intervention for acquired pulmonary vein stenosis.  相似文献   
949.
MVI Block vs Trigger Ablation in PMFL . Introduction: Patients with previous ablation for atrial fibrillation (AF) may experience recurrence of perimitral flutter (PMFL). These arrhythmias are usually triggered from sources that may also induce AF. This study aims at determining whether ablation of triggers or completing mitral valve isthmus (MVI) block prevents more arrhythmia recurrences. Methods and Results: Sixty‐five patients with recurrent PMFL after initial ablation of long standing persistent AF were included in this study. Thirty‐two patients were randomized to MVI ablation only (Group 1) and 33 were randomized to cardioversion and repeat pulmonary vein (PV) isolation plus ablation of non‐PV triggers (Group 2). MVI bidirectional block was achieved in all but 1 patient from Group 1. In Group 2, reconnection of 17 PVs was detected in 14 patients (42%). With isoproterenol challenge, 44 non‐PV trigger sites were identified in 28 patients (85%, 1.57 sites per patient). At 18‐month follow‐up, 27 patients (84%) from Group 1 had recurrent atrial tachyarrhythmias, of whom 15 remained on antiarrhythmic drug (AAD); however, 28 patients from Group 2 (85%, P < 0.0001 vs Group 1) were free from arrhythmia off AAD. The ablation strategy used in Group 2 was associated with a lower risk of recurrence (hazard ratio = 0.10, 95% CI 0.04–0.28, P < 0.001) and an improved arrhythmia‐free survival (log rank P < 0.0001). Conclusion: In patients presenting with PMFL after ablation for longstanding persistent AF, MVI block had limited impact on arrhythmia recurrence. On the other hand, elimination of all PV and non‐PV triggers achieved higher freedom from atrial arrhythmias at follow‐up. (J Cardiovasc Electrophysiol, Vol. 23, pp. 137‐144, February 2012)  相似文献   
950.
Vein of Marshall Ethanol in Recurrent AF. Introduction: Atrial fibrillation (AF) or flutter can recur after pulmonary vein (PV) antral isolation (PVAI). The vein of Marshall (VOM) has been linked to the genesis of AF. We hypothesized that the VOM may play a role in AF recurrences and that VOM ethanol infusion may have therapeutic value in this setting. Methods and Results: Sixty-one patients with recurrent AF or flutter after PVAI were studied. The VOM was successfully cannulated in 54; VOM and PV electrograms were recorded, and differential PV-VOM pacing was performed. VOM signals were present in all patients; however, VOM triggers of AF could not be demonstrated. VOM tachycardia was present in 1 patient. Left inferior (LIPV) and left superior (LSPV) reconnection was present in 32 and 30 patients, respectively. Differential pacing in VOM and LIPV showed VOM-mediated LIPV reconnection in 5/32 patients. In others, VOM and PV connected indirectly via left atrial tissues. Up to four 1 cc infusions of 98% ethanol were delivered in the VOM. Regardless of the reconnection pattern, ethanol infusion eliminated LIPV and LSPV reconnection in 23/32 and 13/30 patients, respectively. Ethanol terminated VOM and LIPV tachycardias in 2 patients. There were no acute procedural complications. Conclusions: VOM signals are consistently present in recurrent AF. VOM may rarely play a role in PV reconnection. However, VOM ethanol infusion can be useful in patients with recurrent AF after PVAI, assisting in achieving redisconnection of reconnected left PVs.  相似文献   
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