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31.
32.
The aim of this study is to provide decision support with artificial intelligence for tendon tissue engineering strategies. The experimental data of tissue-engineered tendons were integrated and standardized with a centralized database, and a decision support system was developed using both artificial neural networks and decision trees. The decision support system was trained with existing cases in the database, and then was used to generate tissue engineering schemes for new experimental animals. Following the schemes generated by the artificial intelligent system, we cured 28 of the 30 experimental animals. In conclusion, artificial intelligence is a powerful method for decision support in the tendon tissue engineering realm.  相似文献   
33.
目的:探讨DSA引导下血管腔内成形术(TA)治疗下肢动脉硬化闭塞症(ASO-LE)的临床效果。方法:2017年3月至2019年4月,手术治疗的ASO-LE患者93例,依据治疗方式的不同分为A组(行TA,n=49)和B组[行下肢动脉旁路移植术(LEABG),n=44],两组患者均在数字减影血管造影(DSA)引导下进行。对比两组患者手术成功率;两组患者术前即刻(T1)、术后1 d(T2)、术后3 d(T3)及术后1周(T4)时刻视觉模拟疼痛评分(VAS);对比术前(T1')、术后1个月(T2')及术后3个月(T3')时刻两组患者下肢缺血程度[患者踝肱指数(ABI)、趾肱指数(TBI)];对比T1'、T2'及T3'时刻两组患者足背动脉血流动力学[足背动脉内径(D)、血流峰速(PV)、血流量(BF)];对比T1'、T2'及T3'时刻两组患者下肢感觉神经传导速度(SNCV)和运动神经传导速度(MNCV);术后6个月,对比两组患者并发症发生率。结果:两组患者手术成功率无显著差异(P>0.05);患者VAS评分组间、时间、交互对比差异均有统计学意义(P<0.05),与T1相比,T2、T3及T4时两组患者VAS评分均降低(P<0.05),与T2相比较,T3及T4时两组患者VAS评分均降低(P<0.05),与T3相比较,T4时两组患者VAS评分均降低(P<0.05),A组T2、T3及T4时刻VAS评分均低于B组(P<0.05);ABI、TBI、D、PV、BF、SNCV和MNCV组间、时间、交互对比差异均有统计学意义(P<0.05);与T1'相比,T2'及T3'时两组患者ABI、TBI、D、PV、BF、SNCV和MNCV均升高(P<0.05);与T2'相比较,T3'时2组患者ABI、TBI、下肢SNCV和MNCV均升高(P<0.05),A组T2'及T3'时刻ABI、TBI、D、PV、BF、SNCV和MNCV均高于B组(P<0.05);A组患者并发症发生率显著低于B组(P<0.05)。结论:相比LEABG,DSA引导下对ASO-LE患者进行TA治疗能够减轻疼痛,改善下肢缺血及足背动脉血流动力学,提高下肢SNCV和MNCV,降低并发症的发生率。  相似文献   
34.

Purpose

To evaluate the safety and effectiveness of combined scoring balloon (SB) and paclitaxel-coated balloon (PCB) angioplasty for stenosis in the dysfunctional hemodialysis access circuit.

Material and methods

Patients were referred from outpatient dialysis centers by their nephrologists because of dysfunctional dialysis access circuit. Fistulogram/graftogram was performed by experienced interventional radiologists. Those with in-stent stenosis, stent edge stenosis or vessel diameter at the culprit segment larger than 6 mm were excluded. Angioplasty of the stenotic segment was performed with SB and followed by PCB. All study outcomes were defined according to the Society of Interventional Radiology technology assessment committee reporting standards for percutaneous interventional procedures in dialysis access circuit.

Results

A total of 23 patients received combined SB/PCB angioplasty for stenosis of hemodialysis access circuit which included 15 fistulas and 8 grafts. There were 10 men and 13 women with a mean age of 63.3 ± 2.7 (SD) years (range: 37–85 years). The technical success and clinical success rates were both 100%. There were no complications during or after the procedures. The target lesion primary patency rates at 3, 6 and 12 months were 91.3%, 69.6%, and 45.2%, respectively and the estimated median target lesion restenosis (TLR) free duration was 11.0 months (95% confidence interval [CI]: 5.1–16.9 months). In patients with a recurrent stenosis, the median TLR-free duration of combined angioplasty was significantly higher than that of prior angioplasty with plain balloon (10.2 months [95% CI: 6.4–14.0 months] vs. 4.2 months [95%CI: 2.1–6.4 months]) (P = 0.047). The mean TLR-free duration was significantly higher in patients with a juxta-anastomotic stenosis than those with non-juxta-anastomotic lesion (21.3 months [95% CI: 14.7–28.0 months] vs. 8.2 months [95% CI: 5.1–11.4 months]) (P = 0.004).

Conclusion

Combined SB/PCB angioplasty is safe and effective for the hemodialysis access stenosis.  相似文献   
35.
目的比较5French(5F)及6French(6F)导引导管在经桡动脉冠状动脉介入治疗(TRI)患者中的安全性及有效性。方法共纳入2009年2月至2010年3月患者,收集相关资料录入数据库,包括患者基线临床资料、导引导管的尺寸、靶血管、靶病变的特点、手术的成功率、手术失败原因、经桡动脉冠状动脉介入治疗手术的成功率及失败原因、患者住院期间主要不良心血管事件率及术后桡动脉闭塞率。结果连续纳入患者共185例,接受195次经桡动脉冠状动脉介入治疗术,平均年龄(57±11)岁(33~81岁);其中54例患者纳入6F导引导管组,共进行56次手术,治疗89处病变;138例患者纳入5F导引导管组,共行146次手术,治疗231处病变。AHA B2/C型病变比例在两组间差异无统计学意义(5F组43.7%/29.0%比6F组46.1%/34.6%,P>0.05),但慢性闭塞性病变、分叉病变、钙化病变5F组显著少于6F组(5.6%比14.6%,P=0.005;23.4%比37.1%,P=0.012;9.5%比47.2%,P<0.001);组间的手术时间[(45±21)min比(46±19)min)]、手术X线曝光时间[(15±12)min比(16±13)min]、使用造影剂量[(140±45)ml比(156±56)ml]差异均无显著统计学意义(P>0.05),但是5F组造影剂用量有减少的趋势(P=0.066);组间住院时间[(1.40±1.26)d比(1.29±0.69)d]和手术成功率(95.2%比94.6%)也差异无统计学意义(P>0.05);5F组1例患者术后桡动脉闭塞,6F组无患者术后桡动脉闭塞(P=1.0),5F组1例发生卒中。结论经桡动脉冠状动脉介入治疗,即使是复杂及高危冠脉病变,5F导引导管有效、安全,手术成功率不低于常规使用的6F导引导管;换用5F导引导管进行冠状动脉介入治疗是一种有吸引力的选择。  相似文献   
36.
Background: Our aim was to evaluate the cost-effectiveness of repeat angioplasty versus new brachiobasilic fistula (BBF) in patients with symptomatic cephalic arch stenosis (CAS). Methods: Patients presenting with symptomatic CAS (n?=?22) underwent angioplasty. They were compared to patients undergoing BBF creation (n?=?51). Primary outcomes were functional primary arteriovenous fistulae patency at 3, 6 and 12 months. Data were collected on number of interventions, alternative accesses and hospital days for access-related complications. Quality of life was assessed using Kidney Disease Quality of Life-36 scores. Decision tree, Monte Carlo simulation and sensitivity analysis permitted cost-utility analysis. Healthcare costs were derived from Department of Health figures and are presented as cost (£)/patient/year, cost/access preserved and cost/quality of life-adjusted year (QALY) for each of the treatment strategies. Results: Functional primary patency rates at 3, 6, 12 months were 87.5%, 81% and 43% for repeated angioplasty and 78%, 63% and 41% for BBF. The angioplasty cohort required 1.64?±?0.23 angioplasties/patient and 0.64?±?0.34 lines/patient. BBF required 0.36?±?0.12 angioplasties/patient and 1.2?±?0.2 lines/patient. Patients in the BBF cohort spent an additional 0.9 days/year in hospital due to access-related complications. Mean cost/patient/year in the angioplasty group was £5247.72/patient/year versus £3807.55/patient/year in the BBF cohort. Mean cost per access saved was £11,544.98 (angioplasty) versus £4979.10 (BBF). Average cost per QALY was £13,809.79 (angioplasty) versus £10,878.72 per QALY (BBF). Conclusions: CAS poses a difficult management problem with poor outcomes from conventional angioplasty. Optimal management will depend on patient factors, local outcomes and expertise, but consideration should be given to creation of a new BBF as a cost-effective means to manage this difficult problem.  相似文献   
37.
Coronary heart disease (CHD) is one of the leading causes of morbidity and the most common cause of death in older adults. Paradoxically, elderly patients tend to be systematically excluded from randomized-controlled cardiovascular trials, which complicates decision-making in this population. Management of CHD in the elderly is frequently more difficult in virtue of chronic comorbid conditions and aging-intrinsic dynamics. Despite these challenges, the number of elderly and very elderly patients undergoing percutaneous coronary interventions (PCI) is increasing. Elderly patients in many registries and large clinical series exhibit even a greater benefit from interventional procedures than younger patients, but they have a higher rate of overall complications. We present an overview of the current available evidence of PCI in older adults with stable and unstable CHD, including comparisons between drug-eluting and bare-metal stents, transfemoral and transradial access, and methods of revascularization. Adjuvant antiplatelet and antithrombotic therapies are also discussed.  相似文献   
38.
BACKGROUND: Although several shortterm animal models of stunning and hibernation have been studied extensively, it has been difficult to produce a consistent animal model of chronic hibernation. The aim of the present study was to develop a nonsurgical porcine stent model of coronary stenosis in order to investigate the relationship between chronic dysfunctional myocardium and viability using 2D-echo, dobutamine stress echo (DSE) and positron emission tomography (PET). METHODS AND RESULTS: Focal progressive coronary stenosis was induced by implantation of an oversized stent in the left anterior descending (LAD) and/or circumflex (LCX) coronary artery in a total of 115 pigs, according to various experimental protocols: copper stent in the LAD (group I, n = 5); noncoated stainless steel stent in the LAD combined with balloon overstretch (group II, n = 7); poly(organo)phosphazene-coated stent in the LAD (group III, n = 77); and poly(organo)phosphazene-coated stent in both the LAD and the LCX (group IV, n = 26). Occurrence of left ventricular dysfunction was evaluated weekly by 2D-echo. At the time of left ventricular dysfunction the presence of viable myocardium within the dysfunctional region was investigated with DSE and PET, and confirmed by histology. The degree of coronary artery stenosis was measured by quantitative coronary angiography and morphometry. Severe coronary artery stenosis in the presence of dysfunctional, but viable, myocardium was induced in groups III and IV (47% and 11% of the animals, respectively). CONCLUSIONS: The authors developed a nonsurgical porcine stent model of progressive coronary stenosis using an oversized polymer-coated stent resulting in chronically decreased myocardial function, with residual inotropic reserve and viable myocardium. This condition may arise from repetitive periods of ischemia, or from sustained hypoperfusion, or a combination of these processes eventually leading to myocardial hibernation. (Int J Cardiovasc Intervent 2000; 3: 111-120)  相似文献   
39.
Major medical society guidelines recommend the measurement of fractional flow reserve (FFR) as an aid in choosing percutaneous coronary intervention in patients with stable coronary artery disease. We investigated the measurement of FFR among interventionalists, analyzing operators'' attributes and decision-making processes to reveal differences in their applications of FFR and the reasons for those differences. An electronic survey study of 1,089 interventionalists was performed from 2 February through 6 March 2012, yielding 255 responses. Most respondents were >45 years old (58%), worked primarily in a community hospital (59%), and performed 10 to 30 cases per month (52%). More than half (145/253, 57%) used FFR measurement in less than one third of cases, and 39 of 253 (15%) never used it. There were no differences in use of FFR by age, practice location, or angiogram volume (P >0.05 for all). Respondents used FFR measurement more frequently than intravascular ultrasonography (73% vs 60%) to help guide the decision to stent (P <0.01). Operators reported that their primary reasons for not using FFR were lack of availability (47%) and problems with reimbursement (39%). There was no difference in FFR use by operator age, practice setting, or case volume.  相似文献   
40.
We report a patient with progressive brainstem infarction despite medical therapy. The patient was transferred to our institution for potential angioplasty of basilar stenosis. Imaging review demonstrated persistent trigeminal artery in situ thrombosis and associated perforating vessel infarction. Persistent trigeminal arteries are commonly associated with an atretic basilar artery and interventional treatment can result in significant morbidity and mortality.  相似文献   
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