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1.

Objective

Symptomatic distal interlocking screws in retrograde femoral nailing are common due the difficulties of imaging the trapezoidal femur. Screws appearing to have appropriate length on imaging may possibly be prominent, creating symptoms. Screw trajectory may influence the degree of this radiographic error. We hypothesize that external rotation of screw trajectory will increase measurement error of screw length.

Design

Retrospective.

Setting

Urban Level I Tertiary Trauma Center.

Participants

283 patients with Computer Tomography (CT) scans of the native knee were retrospectively identified. Simulation was done of the trajectory of an interlock at 20?mm and 40?mm proximal to the nail entry point, which represent common screw positions associated/not associated respectively, with removal. The distance between the radiographic medial cortex and the tip of the transverse screw was calculated (D). The angle (Ψ) between the transverse trajectory and a modified trajectory aimed at the most medial cortex to avoid radiographic measurement error was calculated. Geometric modeling was utilized to calculate the measurement error (D) in the event of accidental external rotation. The angle of the medial slope was also measured (Θ).

Intervention

Review of CT imaging of normal distal femora.

Main Outcome Measurements

CT measurements of distal femora.

Results

The mean distance (D) at 20/40?mm was 4.21 [95%CI 4.02–4.402] and 2.03?mm [95%CI 1.78–2.83], respectively (p?<?0.0001). The mean angle (Ψ) between the transverse and modified trajectory at 20/40?mm was 12° [95%CI 11.5–12.5] and 9.60° [95%CI 9–10.2], respectively (p?<?0.0001). External rotation by a similar amount nearly triples the measured difference (D). The measured medial slope was significantly increased as screws were placed more proximal (Θ20 mm 46.5 vs Θ40 mm: 48.7?°, p?<?0.00001).

Conclusion

The distance between the perceived medial cortex and the tip of the most transverse screw is 4.21?mm and could account for painfully prominent screws. In more proximal screws this distance is decreased. Internal rotation of the screw trajectory 12° can reduce this distance (D), which has implications in nail design. External rotation, amplifies this difference nearly three-fold. Surgeons should avoid external rotation of the aiming arm to prevent prominent screws.  相似文献   
2.

Objective

Acute mesenteric ischemia (AMI) is an emergent event with a high mortality rate; survivors have high rates of intestinal failure. Restoration of blood flow using endovascular or surgical revascularization is associated with better outcome in terms of survival rate and intestinal resection. Retrograde open mesenteric stenting (ROMS), which is a hybrid technique, combines two benefits: prompt blood flow restoration with an endovascular approach and inspection and resection of the small bowel. The aim of the study was to assess the results of ROMS in thrombotic AMI in a retrospective multicenter study.

Methods

We retrospectively enrolled all consecutive patients who underwent ROMS revascularization for occlusive thrombotic AMI in three participating tertiary care centers between November 2012 and March 2017.

Results

Twenty-five patients (14 men and 11 women; mean age, 64.9 ± 11.6 years) were included. In two patients, ROMS was not possible because of failure of re-entry in the aortic lumen (technical success, 92%). One patient required revascularization of two visceral arteries and underwent an aortohepatic bypass. Five patients (20%) underwent endarterectomy and patch angioplasty of the superior mesenteric artery before retrograde stenting. Thirteen patients (52%) required bowel or colon resection (11 patients required both resections) during the initial procedure with a mean length of small bowel resection of 52 ± 87 cm. The 30-day operative mortality rate was 25%, and the overall 1-year survival rate was 65%. The 1-year primary patency rate was 92%. In one patient, postoperative imaging at 1 month showed stent migration in the aortic bifurcation.

Conclusions

ROMS for thrombotic AMI has a high technical success rate and a high midterm primary patency rate. It could be an alternative procedure to retrograde superior mesenteric artery bypass for patients when percutaneous endovascular revascularization is not indicated or has failed.  相似文献   
3.
《The Journal of arthroplasty》2019,34(7):1462-1469
BackgroundTwo-stage revision with static antibiotic spacers is the preferred treatment for chronically infected total knee arthroplasty (TKA) associated with severe bone loss. Intramedullary rods to reinforce static spacers have been described. On those, however, bacterial colonization may occur and hamper infection control. This study reports the microbiological findings on the spacer rods and the treatment outcome among these patients.MethodsWe reviewed 97 infected TKA with extensive bone loss treated with antibiotic-loaded cement spacers reinforced with intramedullary rods. Mean interim period with the spacer in situ was 9 weeks (range: 6-24 weeks). Intraoperative cultures and sonicated spacer rods were analyzed. Mean follow-up after TKA reimplantation was 41 months (range: 27-56 months). Treatment success was defined using the modified Delphi consensus criteria.ResultsTwenty-two patients (23%) had treatment failure, including 3 reinfections caused by the same organism, 9 reinfections caused by a different organism, 9 patients required interim spacer exchange, and 1 patient died in the early postoperative course. Sonication cultures of the spacer rods were positive in 2 cases (2%), and none of them failed. Host and limb status was significantly worse in patients who sustained reinfection. At the latest follow-up, all patients had a TKA in place, and 2 patients received chronic antibiotic suppression.ConclusionTwo-stage revision with the use of intramedullary rods is a safe and efficient treatment for chronically infected TKA with severe bone loss. Most reinfections grew different organisms compared with initial infection. Compromised hosts and extremities may be subjected to chronic antibiotic suppression.  相似文献   
4.
目的探讨TRIGEN股骨髓内钉在股骨骨折中的应用效果。方法对54例股骨骨折患者采用TRIGEN股骨髓内钉治疗,记录髓内钉远端锁钉时间、透视次数、一次锁钉成功率及骨折愈合时间。结果54例均获得随访,时间8~36个月。患者骨折均愈合,愈合时间3~14个月。均无伤口感染、血管神经损伤。Sureshot远端瞄准系统远端锁钉时间为142~412 s,一次锁钉成功率为97.2%,透视次数为1~6次。结论TRIGEN股骨髓内钉治疗股骨骨折治疗效果满意,具有损伤小、固定简便、并发症少等优点;Sureshot远端瞄准系统一次锁钉准确率高、操作时间短、放射量小。  相似文献   
5.
6.
《Brain stimulation》2020,13(5):1284-1295
BackgroundElectroconvulsive therapy (ECT) technique is often changed after insufficient improvement, yet there has been little research on switching strategies.ObjectiveTo document clinical outcome in ECT nonresponders who were received a second course using high dose, brief pulse, bifrontotemporal (HD BP BL) ECT, and compare relapse rates and cognitive effects relative to patients who received only one ECT course and as a function of the type of ECT first received.MethodsPatients were classified as receiving Weak, Strong, or HD BP BL ECT during three randomized trials at Columbia University. Nonresponders received HD BP BL ECT. In a separate multi-site trial, Optimization of ECT, patients were randomized to right unilateral or BL ECT and nonresponders also received further treatment with HD BP BL ECT.ResultsRemission rates with a second course of HD BP BL ECT were high in ECT nonresponders, approximately 60% and 40% in the Columbia University and Optimization of ECT studies, respectively. Clinical outcome was independent of the type of ECT first received. A second course with HD BP BL ECT resulted in greater retrograde amnesia immediately, two months, and six months following ECT.ConclusionsIn the largest samples of ECT nonresponders studied to date, a second course of ECT had marked antidepressant effects. Since the therapeutic effects were independent of the technique first administered, it is possible that many patients may benefit simply from longer courses of ECT. Randomized trials are needed to determine whether, when, and how to change treatment technique in ECT.  相似文献   
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8.
目的研究分析交锁髓内钉内固定术对创伤性下肢长管状骨骨折的治疗效果。方法将2017年4月-2018年4月本院收治的180例创伤性下肢长管状骨骨折患者进行本次研究,按挂号先后顺序均分为参照组和观察组,各90例。参照组用钢板内固定术治疗,观察组用交锁髓内钉内固定术治疗,比较两组的愈合情况和并发症发生情况。结果治疗后,参照组的愈合情况显著差于观察组;参照组的并发症发生情况高于观察组,采用有统计学意义(P<0.05)。结论交锁髓内钉内固定术对创伤性下肢长管状骨骨折的治疗有非常好的效果,保障了患者的恢复情况,减少了患者治疗后的并发症情况。  相似文献   
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