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71.
72.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(8):699-713
The first application of a Sonogashira cross‐coupling reaction in 18F chemistry has been developed. The reaction was exemplified by the cross‐coupling of terminal alkynes (ethynylcyclopentyl carbinol 6 , 17α‐ethynyl‐3,17β‐estradiol 7 and 17α‐ethynyl‐3‐methoxy‐3,17β‐estradiol 8 ) with 4‐[18F]fluoroiodobenzene. 4,4′‐Diiododiaryliodonium salts were used as precursors for the synthesis of 4‐[18F]fluoroiodobenzene, enabling the convenient access to 4‐[18F]fluoroiodobenzene in 13–70% yield using conventional heating or microwave activation. The Sonogashira cross‐coupling of 4‐[18F]fluoroiodobenzene with terminal alkynes gave the corresponding 4‐[18F]fluorophenylethynyl‐substituted compounds [18F]‐9 , [18F]‐10 and [18F]‐13 in yields up to 88% within 20 min of starting from 4‐[18F]fluoroiodobenzene. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
73.
Toshikazu Tanaka Peter C Amadio Chunfeng Zhao Mark E Zobitz Kai-Nan An 《Journal of orthopaedic research》2006,24(4):757-762
While attrition from sharp bony surfaces is the most common cause of extensor digiti minimi (EDM) tendon rupture, the etiology of other cases of spontaneous EDM tendon rupture is still unknown. Friction within the compartment may play a role, especially with ulna dislocation. The purpose of this study was to compare gliding resistance of the EDM tendon with that of a tendon which rarely ruptures spontaneously, the extensor digitorum communis of the middle finger (EDC III) tendon, under various wrist and ulna head positions. Eight fresh frozen cadavers were used. Gliding resistance between the tendon and its sheath in each compartment was measured in five different wrist positions and three different ulna head positions. Gliding resistance of the EDM tendon (0.13 +/- 0.03 N) was significantly greater than the EDC III tendon (0.09 +/- 0.03 N) (p < 0.05). For the EDM tendon, the gliding resistance in ulnar deviation or pronation was higher than the gliding resistance in neutral, radial deviation, or supination (p < 0.05), and the gliding resistance with ulnar lengthening (over 6 mm) or dorsal ulnar dislocation (over 9 mm) was higher than in neutral ulnar head positioning. For the EDC III tendon, the gliding resistance in ulnar deviation was significantly higher than the gliding resistance in neutral, radial deviation, or supination, or dorsal dislocation with ulnar lengthening (p < 0.05). Wrist ulnar deviation, ulnar dorsal dislocation (over 9 mm), and ulnar lengthening (over 6 mm) increased the gliding resistance of the EDM tendon. In patients at risk for EDM rupture, such as those with rheumatoid arthritis or distal radioulnar joint osteoarthritis, avoiding such positions may be advantageous. 相似文献
74.
踝部开放性骨折的急症手术治疗 总被引:5,自引:0,他引:5
目的探讨踝部开放性骨折的损伤特点及相关的急症手术技术特点。方法2001年8月至2006年4月,急症手术治疗踝部开放性骨折51例,男39例,女12例;年龄18-72岁,平均36岁。伤口Gustilo分度,Ⅰ度3例,Ⅱ度37例,ⅢA度7例,ⅢB度3例,ⅢC度1例。急诊给予有效抗生素治疗,尽早开始手术。冲洗及彻底清创后,根据骨折类型、粉碎程度及伤口情况制定骨折处理的顺序,依次完成骨折复位、固定。结果48例患者获得随访,随访时间8-48个月,平均26个月。无一例发生深部感染。12例伤口发生浅表皮缘坏死,2例伤口延迟愈合,2例伤口发生浅表感染。踝部骨折在10-18周(平均13周)愈合。采用AOFAS踝后足功能评分标准,48例评分在76-100分,平均90分。结论踝部开放性骨折在急症手术时应彻底清创,注意保护皮肤活力。在处理后踝骨折时,可采用胫骨远端脱出法。多数手术应先精确复位、固定外踝骨折,对旋后内收型、外踝严重粉碎的踝部骨折应先进行内踝骨折的复位、固定。对严重的下胫腓联合分离,应直视下复位且常规使用下胫腓螺钉固定。 相似文献
75.
人工肱骨头置换术后大结节影像学改变与肩关节功能 总被引:5,自引:0,他引:5
目的观察新鲜复杂肱骨近端骨折行人工肱骨头置换术后随访X线片上重建大结节影像的动态改变,探讨其原因及其与肩关节功能的关系。方法2002年2月至2005年7月应用人工肱骨头置换治疗新鲜复杂肱骨近端骨折68例,59例术后随访1年以上。男28例,女31例;年龄28~80岁,平均59岁。以随访中肩关节外旋正位X线片上出现大结节影像明显变化的8例为研究组,其余患者为对照组。比较两组的肩关节功能,明确大结节影像改变的临床意义。结果两组术后主动前屈上举角度、主动前屈上举肌力、主动体侧外旋肌力、SST评分以及ASES评分的差异均有统计学意义(P〈0.05);而主动体侧外旋角度和主动体侧内旋的差异无统计学意义。结论复杂肱骨近端骨折患者应用人工肱骨头置换术后,若随访过程中逐渐出现肩关节外旋正位X线片上大结节影像明显减小甚至消失可能预示肩关节功能恢复不佳。推测造成这种大结节改变的原因是多方面的,其中包括大结节骨块血运差导致的部分骨吸收,以及大结节骨块不愈合导致的骨块进一步移位。 相似文献
76.
目的探讨关节镜下肩袖缝合术治疗肩袖撕裂的手术方法和临床效果。方法2002年12月至2005年10月,对27例肩袖撕裂患者行关节镜下肩袖缝合术,25例获得1年以上随访,其中男12例,女13例;年龄35~67岁,平均54.3岁;左肩6例,右肩19例,涉及优势侧19例。10例滑囊侧部分撕裂,1例滑囊侧及关节侧均有部分撕裂,14例全层撕裂。术前均拍摄肩关节正位和冈上肌出口位X线片,21例行B超检查,23例行MR或MRA检查。全部病例行肩峰下滑囊切除及前肩峰成形术。肩袖修复方式:1例直接行断端缝合,15例应用缝合锚钉行肩袖止点重建,9例联合应用断端缝合及缝合锚钉技术。分别在术前和最终随访时采用UCLA肩关节评分标准进行评价。结果随访时间1~3年,平均23个月。术后平均UCLA评分为(32.3±t2.3)分。手术前后疼痛评分平均为(2.6±t0.9)分和(8.6±1.4)分(P=0.000),功能评分平均为(5.0±1.8)分和(9.1±1.0)分(P=0.000),肩关节主动前屈评分平均为(3.6±1.5)分和(4.9±10.3)分(P=0.000),前屈肌力评分平均为(4.0±0.6)分和(4.7±0.5)分(P=0.000),差异均有统计学意义。优8例、良17例,所有患者均对手术效果表示满意。结论关节镜下肩袖缝合术是治疗肩袖撕裂的有效方法。术中应有效地控制出血,适度进行肩峰成形,正确识别撕裂的形状,充分松解粘连并采用恰当的缝合方式。手术创伤小、恢复快,其疗效可达到切开手术水平。 相似文献
77.
Devices that are pinned to the tibia to tension an anterior cruciate ligament (ACL) graft produce joint reaction loads that in turn can affect the maintenance of graft initial tension after tibial fixation and hence knee anterior-posterior (AP) load-displacement. However, the effect of these devices on AP load-displacement is unknown. Our objectives were to determine whether tensioning by device versus tensioning by hand causes differences in AP load-displacement and intraarticular graft tension for two commonly used tibial fixation devices: a bioresorbable interference screw and a WasherLoc. AP load-displacement and intraarticular graft tension were measured in 20 cadaveric knees using a custom arthrometer. An initial tension of 110 N was applied to a double-looped tendon graft with the knee at extension using a tensioning device pinned to the tibia and a simulated method of tensioning by hand. After inserting the tibial fixation device, the 134 N anterior limit (i.e., anterior position of the tibia with respect to the femur with a 134 N anterior force applied to the tibia) and 0 N posterior limit (i.e., AP position of the tibia relative to the femur with a 0 N force applied to the tibia) were measured with the knee in 25 degrees flexion. Intraarticular graft tension was measured at extension. These limits and intraarticular graft tension were also measured after cyclically loading the knee 300 times. Compared to a simulated method of tensioning by hand, tensioning with a device pinned to the tibia did not decrease the 134 N anterior limit and did not cause posterior tibial translation. However, intraarticular graft tension was maintained better with a tensioning device pinned to the tibia for the Washerloc, but not the interference screw. For two commonly used tibial fixation devices, a tensioning device pinned to the tibia does not improve AP load-displacement at 25 degrees flexion over tensioning by hand when the graft is tensioned at full extension, but does improve the maintenance of intraarticular graft tension for the Washerloc. 相似文献
78.
C. J. Snijders PhD A. Vleeming PhD R. Stoeckart PhD 《Clinical biomechanics (Bristol, Avon)》1993,8(6):285-294
This study deals primarily with the stability of the base of the spine. The sacroiliac joints are vulnerable to shear loading on account of their predominantly flat surfaces. This raises the question of what mechanisms are brought into action to prevent dislocation of the sacroiliac joints when they are loaded by the weight of the upper part of the body and by trunk muscle forces. First a model is introduced to compare load transfer in joints with spherical and with flat joint surfaces. Next we consider a biomechanical model for the equilibrium of the sacrum under load, describing a self-bracing effect that protects the sacroiliac joints against shear according to ‘the sacroiliac joint compression theory’, which has been demonstrated in vitro. The model shows joint stability by the application of bending moments and the configuration of the pelvic arch. The model includes a large number of muscles (e.g. the gluteus maximus and piriformis muscles), ligaments (e.g. the sacrotuberous, sacrospinal, and dorsal and interosseous sacroiliac ligaments) as well as the coarse texture and the ridges and grooves of the joint surfaces. 相似文献
79.
80.
月骨周围进行性不稳定的腕运动力学研究 总被引:3,自引:0,他引:3
目的探索腕月骨周围进行性不稳定的运动力学变化。方法对14具新鲜冷冻尸体腕关节,用计算机辅助测量了正常腕和各阶段月骨周围不稳定时腕动力肌腱在腕屈伸、尺桡偏时滑动幅度,根据肌腱滑动幅度和关节运动范围计算动力肌腱力臂。结果月骨周围进行性不稳定时屈腕肌腱力臂明显增大,屈指肌腱力臂减小;桡侧腕动力肌腱力臂以增大为主,尺侧肌腱力臂以减小为主。桡侧腕屈肌腱在腕屈伸或尺桡偏时均显著增大。结论腕运动力学变化对月骨周围不稳定的形成、运动力学变化、腕部塌陷起重要起动作用。 相似文献