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1.
Advancing appropriate microcatheters is essential for treatment. However, we still encounter inaccessible arterial branches because of the anatomical arrangement. While many successful techniques regarding microcatheters have been reported, there have been very few reports of microguidewire-shaping techniques. We developed the Simmons-Angled microguidewire INsertion to the Target (SAINT) technique for insertion of the microguidewire into inaccessible arterial branches. The SAINT technique is feasible for selection and insertion into arteries that are inaccessible with conventional methods.  相似文献   
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PurposeTo evaluate the potential differences in non-target embolization and vessel microsphere filling of a reflux-control microcatheter (RCM) compared to a standard end-hole microcatheter (SEHM) in a swine model.Materials and methodsRadiopaque microspheres were injected with both RCM and SEHM (2.4-Fr and 2.7-Fr) in the kidneys of a preclinical swine model. Transarterial renal embolization procedures with RCM or SEHM were performed in both kidneys of 14 pigs. Renal arteries were selectively embolized with an automated injection protocol of radio-opaque microspheres. Ex-vivo X-ray microtomography images of the kidneys were utilized to evaluate the embolization by quantification of the deposition of injected microspheres in the target vs. the non-target area of injection. X-ray microtomography images were blindly analyzed by five interventional radiologists. The degree of vessel filling and the non-target embolization were quantified using a scale from 1 to 5 for each parameter. An analysis of variance was used to compare the paired scores.ResultsTotal volumes of radio-opaque microspheres injected were similar for RCM (11.5 ± 3.6 [SD] mL; range: 6–17 mL) and SEHM (10.6 ± 5.2 [SD] mL; range: 4–19 mL) (P = 0.38). The voxels enhanced ratio in the target (T) vs. non-target (NT) areas was greater with RCM (T = 98.3% vs. NT = 1.7%) than with SEHM (T = 89% vs. NT = 11%) but the difference was not significant (P = 0.30). The total score blindly given by the five interventional radiologists was significantly different between RCM (12.3 ± 2.1 [SD]; range: 6–15) and the standard catheter (11.3 ± 2.5 [SD]; range: 4–15) (P = 0.0073), with a significant decrease of non-target embolization for RCM (3.8 ± 1.3 [SD]; range: 3.5–4.2) compared to SEHM (3.2 ± 1.5 [SD]; range: 2.9–3.5) (P = 0.014).ConclusionIn an animal model, RCM microcatheters reduce the risk of non-target embolization from 11% to 1.7%, increasing the delivery of microspheres of 98% to the target vessels, compared to SEHM microcatheters.  相似文献   
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《Surgery (Oxford)》2020,38(7):411-417
Intestinal and multivisceral transplantation can be a lifesaving treatment for patients with complications from the treatment of intestinal failure. However, the indications for this highly specialized treatment are broadening and include other such indications as patients with acute abdominal vascular catastrophes as well as patients with previously unresectable benign intra-abdominal tumours. Since the first successful multivisceral transplant in the late 1980s, the field has expanded and more than 4000 transplants have taken place worldwide and outcomes continue to improve. However, complications are still commonplace and multivisceral and intestinal transplant recipients are more likely to suffer from the complications of transplantation than any other solid organ transplant group. The most important complications are rejection and sepsis, with sepsis remaining the leading cause of death in this patient group. That said the outcomes for intestine alone transplants have improved to such a degree that they are close to that of intestinal failure patients on long-term parenteral nutrition and therefore we may be entering an era where intestinal transplantation will be offered as an alternative to parenteral nutrition for patients with intestinal failure.  相似文献   
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目的探讨近端血流阻断加压技术在硬脊膜动静脉畸形(SDAVF)血管内治疗中应用的安全性和有效性。方法回顾性分析2017年2月至2018年9月海军军医大学附属长海医院神经外科采用血管内治疗的6例SDAVF患者的临床资料。所有患者术中均应用近端血流阻断加压技术,其中1例因未能完全栓塞,改为显微外科手术治疗。术后即刻行数字减影血管造影(DSA),以判断栓塞情况。对所有患者行门诊或电话随访,随访内容为行Aminoff-Logue评分,判断脊髓功能的恢复情况;门诊随访的患者同时复查脊髓MRI,以判断栓塞情况。结果6例患者的手术均成功。术后即刻DSA显示,5例完全栓塞,1例瘘口残留。所有患者术后均未出现永久性神经系统并发症;其中1例术中造影显示肋间动脉夹层的患者,采用弹簧圈闭塞近端肋间动脉后复查胸椎CT,显示肋间肌内血肿形成,术后持续胸背部疼痛3 d后缓解。6例患者中,5例为门诊随访,1例为电话随访;中位随访时间(范围)为5.5个月(4.0~22.0个月)。术后3个月,6例患者的Aminoff-Logue评分均较术前降低[(2.0±0.7)分、(4.0±1.5)分,P<0.05];脊髓功能得到明显改善。术中因拔管困难而留置体内的1例患者,术后6个月随访时无相关并发症。经显微手术治疗的1例患者出院后10个月行DSA随访,未见瘘口显影。结论初步推测近端血流阻断加压技术在SDAVF血管内治疗中是安全、有效的。  相似文献   
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PurposeTo retrospectively assess immediate and 1-year success rate of type 2 endoleak (T2E) treatment with ethylene-vinyl-alcohol-polymer using three-dimensional (3D) image fusion guidance with cone beam computed tomography via trans-arterial embolization (TAE) or direct percutaneous sac injection (DPSI).Materials and methodsA total of 37 patients with T2E who were treated either using TAE (34/37; 92%) or DPSI (9/37; 8%) were included. There were 34 men and 3 women with a mean age of 86 ± 9 (SD) years (range: 67–104 years). Mean aneurysm diameter was 67 ± 14 (SD) mm (range: 42–101 mm) at pre-procedure evaluation. Immediate success was complete embolization of the sac and feeding artery. 1-year success was reduction or stability of the aneurysmal sac diameter based on pre-procedure and 12-month follow-up examinations. Safety (treatment-related complications), patient demographics, duration of procedure and contrast volume were reported.ResultsImmediate and 1-year successful outcomes were reported in 94% (n = 32) and 88% (n = 28) of patients after TAE and 100% (n = 9) and 89% (n = 8) after DPSI. T2E treatments were immediately successful for 95% of the procedures (41/43) and for 88% (36/41) at 1 year. Overall, T2E treatment was effective in 33 patients (89%). No major complications occurred. Mean procedure time and contrast volume were significantly different between the 2 techniques with respectively 87 ± 16 (SD) min (range: 65–120 min) and 75 ± 26 (SD) mL (range: 40–130 mL) for TAE and 32 ± 10 (SD) min (range: 20–50 min) (P < 0.01) and 6 ± 6 (SD) mL (range: 2–22 mL) (P < 0.01) for DPSI. Mean aneurysm diameter at 1-year was 68 ± 17 (SD) mm (range: 43–101 mm). No significant differences in the pre-procedure sac diameter were found at long-term follow-up between patients without T2E and those with persistent T2E (P = 0.1) in the successful embolization group (n = 33).ConclusionTAE or DPSI treatments of T2E with ethylene-vinyl-alcohol-polymer using 3D-image fusion guidance were immediately successful for 95% of the procedures and remained effective for 88%. Longer follow-up is necessary to assess sac stability in the case of persistent endoleak.  相似文献   
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Visceral artery aneurysms (VAA) include splanchnic and renal artery aneurysms. They represent a rare clinical entity, although their detection is rising due to an increased use of cross-sectional imaging. Rupture is the most devastating complication, and is associated with a high morbidity and mortality. In addition, increased percutaneous endovascular interventions have raised the incidence of iatrogenic visceral artery pseudoaneurysms (VAPAs). For this reason, elective repair is preferable in the appropriately chosen patient. Controversy still exists regarding their treatment. Over the past decade, there has been steady increase in the utilization of minimally invasive, non-operative interventions, for vascular aneurysmal disease. All VAAs and VAPAs can technically be fixed by endovascular techniques but that does not mean they should. These catheter-based techniques constitute an excellent approach in the elective setting. However, in the emergent setting it may carry a higher morbidity and mortality. The decision for intervention has to take into account the size and the natural history of the lesion, the risk of rupture, which is high during pregnancy, and the relative risk of surgical or radiological intervention. For splanchnic artery aneurysms, we should recognize that we are not, in reality, well informed about their natural history. For most asymptomatic aneurysms, expectant treatment is acceptable. For large, symptomatic or aneurysms with a high risk of rupture, endovascular treatment has become the first-line therapy. Treatment of VAPAs is always mandatory because of the high risk of rupture. We present our point of view on interventional radiology in the splanchnic arteries, focusing on what has been achieved and the remaining challenges.  相似文献   
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ObjectiveArterial stenosis is a major obstacle for subsequent interventional procedures. We hypothesized that the stenosis is caused by gelatin sponge embolization and performed an experimental study in a rabbit renal model.ResultsGelatin sponge particles were mainly observed in the segmental and interlobar arteries. Transmural inflammation of the embolized arterial wall and mild thickening of the media were observed 1 week after embolization. Resorption of the gelatin sponge and organization of thrombus accompanied by foreign body reactions, were observed from 2 to 4 weeks after embolization. Microscopic images of the 3 weeks group showed vessel lumens filled mostly with organized thrombi, resulting in severe stenosis. Additionally, vessels showed a thickened intima that contained migrating smooth muscle cells and accompanying interruption of the internal elastic lamina. The migrating smooth muscle cells were distributed around the recanalized arterial lumen.ConclusionGelatin sponge embolization may induce arterial stenosis by causing organized thrombus and intimal hyperplasia, which consists of migrating smooth muscle cells and intimal collagen deposits.  相似文献   
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目的系统评价颅内破裂动脉瘤夹闭术和栓塞术后分流依赖性脑积水发生率。方法以脑积水、夹闭、介入、栓塞、颅内动脉瘤、脑动脉瘤、蛛网膜下腔出血/蛛网膜下隙出血,以及hydrocephalus、shunt、clipping、coiling、surgical、endovascular、embolization、treatment、intracranial aneurysm、cerebral aneurysm、subarachnoid hemorrhage等中英文词组,计算机检索1990年1月-2015年9月美国国立医学图书馆生物医学信息检索系统、荷兰医学文摘、Cochrane临床对照试验中心注册库、中国知网中国知识基础设施工程、万方数据库,辅助手工检索《中华神经外科杂志》、《中国现代神经疾病杂志》和《中国脑血管病杂志》等相关杂志,查阅关于颅内破裂动脉瘤夹闭术和栓塞术后分流依赖性脑积水发生率的临床研究。采用Jadad量表和Newcastle-Ottawa量表评价文献质量,Rev Man 5.3和Stata 13.1统计软件进行Meta分析。结果共获得731篇文献,经剔除重复和不符合纳入标准者,最终纳入18项临床试验共计15 920例颅内破裂动脉瘤患者,行夹闭术者10 038例、行栓塞术5882例。Meta分析显示:两种治疗方式术后分流依赖性脑积水发生率差异无统计学意义(OR=0.860,95%CI:0.720~1.030;P=0.110);分析结果的稳定性较差,但不存在发表偏倚(Egger法:P=0.795)。结论颅内破裂动脉瘤夹闭术和栓塞术后分流依赖性脑积水发生率无显著差异,但尚待进一步的高质量临床研究加以证实。  相似文献   
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