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951.
Objectives: To determine surgical and prosthodontic outcomes of mandibular single‐implant overdentures, opposing complete maxillary dentures, using a wide diameter implant and large ball attachment system compared with different regular diameter implants with standard attachment systems. Materials and methods: Thirty‐six edentulous participants (mean age 68 years, SD 9.2) were randomly assigned into three treatment groups (n=12). A single implant was placed in the mandibular midline of participants to support an overdenture using a 6‐week loading protocol. The control group received Southern regular implants and standard ball attachments. One group received Southern 8‐mm‐wide implants and large ball attachments. Another group received Neoss regular implants and Locator attachments. Parametric and non‐parametric tests of a statistical software package (SPSS) were used to determine between groups differences in marginal bone loss, implant stability, implant, and prosthodontic success (P<0.05). Results: Implant success after 1 year was 75% for Southern regular implant (control) group; and 100% for the Southern wide and Neoss regular implant groups (P=0.038). Mean marginal bone loss at 1 year was 0.19 mm (SD 0.39) without significant differences observed. Implant stability quotient (ISQ) at baseline was significantly lower for the Southern regular (control) group than the other two groups (P=0.001; P=0.009). At 1 year, no significant difference in implant stability was observed (mean ISQ 74.6, SD 6.1). The change in implant stability from baseline to 1 year was significant for the control group (P=0.025). Prosthodontic success was comparable between the groups but the maintenance (41 events overall, mean 1.2) was greater for the Locator and the standard ball attachments. Conclusions: Mandibular single‐implant overdentures are a successful treatment option for older edentulous adults with early loading protocol using implants of different diameters and with different attachment systems. To cite this article:
Alsabeeha NHM, Payne AGT, De Silva RK, Thomson WM. Mandibular single‐implant overdentures: preliminary results of a randomised‐control trial on early loading with different implant diameters and attachment systems.
Clin. Oral Impl. Res. 22 , 2011; 330–337.
doi: 10.1111/j.1600‐0501.2010.02004.x  相似文献   
952.
953.

目的:评价双眼外直肌后徙与单眼一退一截手术对基本型间歇性外斜视手术疗效。

方法:电子检索1970-01/2018-01的PubMed数据库、EMBASE、Cochrane library、Web of Science、Clinical Trial,中国生物医学文献数据库、万方医学网。纳入比较双眼外直肌后徙与单眼一退一截手术对基本型间歇性外斜视手术疗效的随机对照研究。由两名评价员独立收集数据并对所得数据及试验质量进行评价,采用STATA14版进行统计分析。

结果:共有5项试验、529例患者符合纳入标准。Meta分析结果提示:与单眼一退一截手术相比,双眼外直肌后徙术术后远期正位率(RR:0.85; 95% CI:0.72~0.99,P=0.043)、术后欠矫(RR:3.975; 95% CI:2.097~7.537, P<0.01)方面差异有统计学意义,远期术后正位率Meta分析的P值随着纳入文献增多逐渐接近0.05。而在术后过矫(RR:0.336; 95% CI:0.049~2.294, P=0.266)差异无统计学意义。

结论:双眼外直肌后徙术相比于单眼一退一截手术对基本型间歇性外斜视手术成功率略低,术后欠矫较明显。  相似文献   

954.
《Journal of endodontics》2020,46(10):1508-1514
IntroductionThis in vitro study sought to compare the efficacy of a sonic irrigant activation device with ultrasonic activation and needle irrigation in removing hard tissue debris (HTD) from anatomic complexities of the root canal system.MethodsTwenty-seven mesial roots of extracted human mandibular molars with 2 canals connected by an isthmus were selected based on micro–computed tomography scans (12-μm voxel size). The mesial canals were mechanically prepared to ProTaper Next X3 (Dentsply Maillefer, Ballaigues, Switzerland) and anatomically distributed into 3 groups (n = 9) according to the final irrigation protocol: sonically activated irrigation (SAI) using the EDDY system (VDW GbmH, Munich, Germany) for 3 × 20 seconds, ultrasonically activated irrigation (UAI) using a size 20 Irrisafe tip (Satelec Acteon, Mérignac, France) for 3 × 20 seconds, and conventional irrigation using a 30-G needle adapted to a syringe. Micro–computed tomographic scans were taken after instrumentation and after supplementary activation of the irrigant. After reconstruction and coregistration, the volume filled with HTD before and after irrigant activation was calculated, and the mean percentage of HTD reduction after final irrigation was compared within and among groups using the paired sample t test and 1-way analysis of variance post hoc Tukey test, respectively (α = 5%).ResultsA significant reduction in the volume filled with HTD after irrigant activation was observed in all groups (P < .05). The percentage reduction of HTD in the UAI group (66.8%) was significantly higher than that in the SAI group (36.4%) (P < .05), whereas the conventional irrigation group result (43.7%) did not differ statistically from the UAI or SAI groups (P > .05).ConclusionsAll tested supplementary irrigation steps significantly reduced the amount of debris created during root canal preparation. Ultrasonic activation resulted in the highest mean debris reduction.  相似文献   
955.
目的:结合动态MRl分析健康人开闭口时下颌运动轨迹特征。方法:18例健康人最大开闭口过程进行动态MRI和下颌运动轨迹描记仪检查,分析髁状突及下颌前牙切点的运动特点及范围。结果:动态MRI显示闭口位关节盘本体部呈双凹形,本体部位于髁状突横嵴的前方(盘分界角〈10。)。健康人下颁前牙切点运动轨迹平滑,双侧运动中心运动轨迹左右对称;运动轴始终保持平行,呈现开闭口初、末时密度比开闭口中时大;运动中心运动距离(13.2±3.1)mm,切点运动距离(41.1±3.8)mm。结论:下颌运动轨迹描记能记录髁状突运动轨迹并且间接反映颞下颌关节的关节盘在开闭口运动中的位置变化情况,为初步建立下颌运动轨迹描记对辅助诊断关节病的参考标准奠定了基础。  相似文献   
956.
Mandibular asymmetry is common among orthognathic patients and exhibits great variation. The aim of this study was to propose a new classification of mandibular asymmetry by anatomical regions; namely R (ramus), B (mandibular body) and C (chin), in conjunction with a corresponding ‘RBC’ three-dimensional (3D) cephalometric analysis. The cone beam computed tomography data of 65 patients with mandibular asymmetry was retrieved to perform the RBC 3D cephalometric analysis and to investigate the characteristics of mandibular asymmetry. It was found that the more posteriorly in mandible, the more pronounced was the vertical asymmetry. Significant transverse asymmetry was only noted in mandibular body. Both mandibular body and chin were significantly asymmetric in length. Seven significant morphologic predictors of menton deviation were identified, namely lower dental midline shift, difference in ramus height, difference in chin length, difference in body length, body height on contralateral side, coronoid height on deviated side and body width on contralateral side, confirming the complex nature of mandibular asymmetry. This simple and concise classification allows comprehensive assessment of mandible morphology by anatomical regions which also facilitates diagnosis, treatment planning and communication in both clinical and research settings.  相似文献   
957.
958.
959.
The purpose of this study was to evaluate surgical outcomes in elderly patients who had undergone free fibula flap transfer for malignant head and neck tumours. A retrospective chart review was performed to identify patients who had undergone free fibula flap transfer for mandibular reconstruction after malignant tumour resection at Jichi Medical University Hospital between May 2009 and April 2015. Enrolled patients were divided into an elderly group (≥80 years old) and a younger group (<80 years old). Seventeen patients met the inclusion criteria and were included in the elderly group. Age at surgery ranged from 80 to 92 years. Thirteen patients (76.5%) experienced postoperative complications. Surgical site complications occurred in seven patients. The success rate of free fibula flap transfer was 100%. Systemic complications occurred in nine patients, most commonly delirium (n = 6). No perioperative mortality was encountered. The overall 1-year survival rate was 94.1% (16/17). No patient reported gait disturbance as a donor site complication or any other major complication. The incidence of postoperative complications did not differ significantly between the elderly and younger groups. Almost no difference in postoperative course was seen between the groups. Elderly patients appear to tolerate free fibula flap reconstruction just as well as younger patients.  相似文献   
960.
《Injury》2016,47(12):2833-2837
ObjectiveThe aim of this study was to assess the functional outcomes after a combined FHL transfer and a gastrocnemius recession for treatment of chronic ruptures of Achilles tendon with a gap and to investigate the patient's satisfaction about the great toe function after transfer.Material and methods19 patients with chronic rupture of the Achilles tendon with a gap were treated with a flexor halluces longus tendon transfer combined with a gastrocnemius recession, Clinical diagnosis depends on the presence of gap in the tendon on examination, inability of tip toe walking on the affected side and positive calf-squeeze test, MRI was used to confirm the clinical diagnosis. American Orthopedic Foot & Ankle Society hind foot score was used for assessment of the results.ResultsThe AOFAS score improved significantly from a mean of 65 preoperatively to 94 at the last follow up (p < 0.001), there was no significant difference in the final outcome between patients with FHL tendon weaved through the stump of the Achilles tendon and those with trans osseous tunnels, the mean AOFAS score at the last follow up was 94.2, 93.8 respectively, no patient complained of big toe dysfunction.ConclusionManagement of chronic rupture of the Achilles tendon with a gap with flexor halluces longus tendon transfer combined with a gastrocnemius recession is a safe and reliable method with a significantly improved functional outcome, muscle advancement through gastrocnemius recession decreases the length of the gap without affecting the muscle function, flexor halluces longus tendon transfer doesn't harm the big toe function.  相似文献   
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