首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5468篇
  免费   322篇
  国内免费   139篇
耳鼻咽喉   13篇
儿科学   13篇
妇产科学   7篇
基础医学   703篇
口腔科学   39篇
临床医学   571篇
内科学   115篇
皮肤病学   13篇
神经病学   257篇
特种医学   646篇
外科学   2504篇
综合类   476篇
预防医学   62篇
眼科学   36篇
药学   247篇
  1篇
中国医学   192篇
肿瘤学   34篇
  2024年   6篇
  2023年   98篇
  2022年   157篇
  2021年   240篇
  2020年   266篇
  2019年   203篇
  2018年   233篇
  2017年   207篇
  2016年   179篇
  2015年   196篇
  2014年   329篇
  2013年   468篇
  2012年   288篇
  2011年   334篇
  2010年   258篇
  2009年   270篇
  2008年   269篇
  2007年   286篇
  2006年   256篇
  2005年   177篇
  2004年   162篇
  2003年   136篇
  2002年   88篇
  2001年   79篇
  2000年   77篇
  1999年   89篇
  1998年   106篇
  1997年   65篇
  1996年   48篇
  1995年   41篇
  1994年   32篇
  1993年   52篇
  1992年   35篇
  1991年   21篇
  1990年   22篇
  1989年   19篇
  1988年   10篇
  1987年   10篇
  1986年   14篇
  1985年   7篇
  1984年   20篇
  1983年   14篇
  1982年   12篇
  1981年   12篇
  1980年   7篇
  1979年   10篇
  1978年   8篇
  1977年   3篇
  1976年   6篇
  1975年   4篇
排序方式: 共有5929条查询结果,搜索用时 15 毫秒
101.
高效液相色谱法测定洛莫司汀脂质体药物含量及包封率   总被引:3,自引:0,他引:3  
目的:建立测定洛莫司汀脂质体药物含量及包封率的RP-HPLC法。方法:采用Diamonsil~(TM)C_(18)柱(250mm×4.6mm,5μm);流动相:乙腈-0.05mol·L~(-1)磷酸二氢铵溶液-三乙胺(60∶40∶0.2,磷酸调pH为3.5);柱温:室温;流速:1.0mL·min~(-1);紫外检测波长:232nm。采用Sephadex G-50分离洛莫司汀脂质体中的游离药物。结果:在本色谱条件下洛莫司汀与辅料及溶剂峰分离良好,洛莫司汀在4.0-48.0μ·mL~(-1)范围内线性关系良好(r=1.0,n=5),回收率在98.0%-101.0%之间,日内RSD及日间RSD均小于2%(n=5)。结论:说明该方法准确可靠、简单快速,可用于洛莫司汀脂质体含量及包封率的测定。  相似文献   
102.
Objective. In magnetic resonance (MR) imaging of the shoulder, oblique coronal images are used for evaluating the supraspinatus tendon (SST) of patients with suspected rotator cuff tear or impingement. This study aimed to compare orientation of the SST long axis with planes perpendicular to the glenohumeral joint (GHJ). Design and patients. The axial scans of 100 consecutive patients referred for MR imaging or MR arthrography of the shoulder were reviewed. Using the electronic cursors of a computer workstation, the angle of the SST long axis was measured and compared with the angle obtained through the GHJ utilizing three different landmarks: perpendicular to the joint (GHJ-90), joint–humeral head center axis (GHJ-H) and joint–scapular body axis (GHJ-S). Results. Differences in angulation between axes of the SST and the three GHJ axes averaged only about 5° [range of means 4.5–5.3°, range of standard deviation (SD) 3.8–4.6°]. In the majority of shoulders, angular differences measured 4 or less for all SST/GHJ comparisons. Similarly, small angular differences in the three GHJ axes were found: 4.5° (SD 3.3°) for GHJ-90/GHJ-S, 5.0° (SD 4.0°) for GHJ-S/GHJ-H and 2.9° (SD 3.0°) for GHJ-90/GHJ-H. Correlation between the GHJ-90 and GHJ-H axes was particularly good, with differences of 4° or less in 84% of shoulders. The orientations of the GHJ axes and that of the SST long axis are comparable. Conclusion. The GHJ may potentially be used as a landmark for obtaining oblique coronal images of the SST. Received: 19 November 1999 Revision requested: 18 January 2000 Revision received: 27 March 2000 Accepted: 5 April 2000  相似文献   
103.
胰岛素固体脂质纳米粒的制备及其理化性质研究   总被引:9,自引:1,他引:9       下载免费PDF全文
 目的 制备胰岛素固体脂质纳米粒并考察其理化性质。方法 采用溶剂扩散法制备胰岛素固体脂质纳米粒,考察制备过程中加入多聚阴离子对纳米粒粒径、表面电位和药物包封率的影响;研究载药纳米粒的体外释放特性;荧光标记固体脂质纳米粒经大鼠口服给药,由荧光倒置显微镜观察血液和淋巴液中的荧光强度。结果胰岛素固体脂质纳米粒的平均粒径为(388.6±143.5)nm,水相中加入三聚磷酸钠对纳米粒粒径无明显影响,而表面电位下降,药物包封率明显增加;胰岛素固体脂质纳米粒最初1 h快速释放了药物包封总量的35.63%,随后以接近每小时1.5%的速度释放,呈明显的缓释特征,24 h体外累积释放量为药物包封量的67.30%;固体脂质纳米粒经大鼠口服研究发现,0.5 h时淋巴液中的荧光强度明显高于相同时间血液中的荧光强度。结论 采用溶剂扩散法制备得到的胰岛素固体脂质纳米粒,具有明显的药物缓释作用;通过调节纳米粒表面电位,可明显提高药物的包封率;固体脂质纳米粒口服给药,具有明显的纳米粒整体淋巴吸收特性。  相似文献   
104.
 目的 探讨可调节带袢锁扣钛板-自体半腱肌肌腱全内重建膝关节前交叉韧带(anterior cruciate ligament,ACL)断裂的可行性、优缺点及并发症。方法 选择2014-07至2015-07应用可调节带袢锁扣钛板-自体半腱肌肌腱全内重建膝关节ACL断裂47例。2~6周,关节镜下应用可调节带袢锁扣钛板-自体半腱肌肌腱全内重建膝关节ACL断裂,伴发内侧副韧带损伤,用股薄肌肌腱修复或直接缝合。取同侧半腱肌肌腱,修整后将肌腱移植物对折成4股,并与可调节带袢锁扣钛板相连,移植物长度为6~6.5 cm,直径为7~9 mm。在ACL胫骨侧、股骨侧印迹定位并用倒打钻钻孔,制作骨隧道,经前内侧入路将肌腱移植物牵入骨道,并两侧逐步锁紧线环,将胫骨向后复位,将钛板固定在骨皮质上。根据重建手术前、后膝关节前抽屉实验、Lachman 试验、侧方挤压实验、IKDC 膝关节功能评价表、 Lysholm 评分对患者进行主观和客观评分,以评定疗效。结果 本组47例随访2~3年,平均随访时间为2.1年。末次随访时,患者膝关节疼痛、肿胀、屈伸活动受限等症状明显改善,前抽屉实验(-),Lachman试验(-),IKDC膝关节功能评分、Lysholm评分较重建前明显提高。膝关节屈曲达115°~130°;膝关节IKDC评分结果:正常41例(87.2%),接近正常4例(8.5%),异常2例(4.3%);膝关节功能Lysholm评分:术前(51.4±5.4)分,术后(92.2±4.6)分,差异有统计学意义(P<0.05)。结论 应用可调节带袢锁扣钛板-自体半腱肌肌腱全内重建膝关节ACL,创伤小,能恢复膝关节的稳定性,功能恢复良好,疗效确切。  相似文献   
105.
《山东中医杂志》2016,(6):522-525
目的 :通过系统评价,比较小针刀疗法和封闭疗法治疗屈指肌腱狭窄性腱鞘炎的疗效以及安全性。方法 :检索中国知网(1962~2015年)、维普数据库(1993~2015年)、万方数据(2000~2015年)、pubmed中文数据库(1994~2015年),并且应用手工输入法检索相关医学期刊,纳入小针刀疗法与封闭疗法对比治疗屈指肌腱狭窄性腱鞘炎的随机对照试验,经2名评价者按要求对筛选后的资料进行交叉核对后,采用Rev Man 5.2软件进行Meta分析。结果:共纳入7个随机对照试验,包含患者1 174例,但没有筛选到高质量文献。Meta分析结果显示,小针刀组治疗屈指肌腱狭窄性腱鞘炎总有效率明显高于对照组,OR=9.07,95%CI[4.64,17.76],Z=6.44,P0.00001;小针刀组治疗屈指肌腱狭窄性腱鞘炎痊愈率明显高于对照组,OR=7.86,95%CI[5.75,10.74],Z=12.93,P0.00001。结论:小针刀治疗屈指肌腱狭窄性腱鞘炎疗效优于封闭疗法。由于纳入试验数目有限且文献质量较低,漏斗图表现出发表偏倚,需设计更严格的随机对照试验来进一步验证上述结论。  相似文献   
106.
107.
Background. Spastic hemiplegia is a common feature after stroke, which can result in a clenched fist deformity with secondary hygienic problems and pain. Operative treatment can improve these problems, although literature about its long-term effects is lacking.

Purpose. To determine whether Superficialis-to-Profundus tendon (StP-) transfer procedure leads to permanent improvement of hygiene and reduction of pain in patients with clenched fist due to spastic hemiplegia following stroke.

Method. Patients who underwent a StP-transfer in 2003 – 2005 were evaluated on skin condition, upper extremity joint mobility, resting position and muscle tone and with VAS scores on hygiene maintenance and pain in the hand.

Results. Six patients (mean age 54 years; duration after stroke 10 years) were included. Indications to operate were hygienic problems only (3) or combined with pain (3). The average follow-up period was 19 months. After 6 weeks of post-operative splinting, no standard follow-up was applied. Serious post-operative complications were not reported. At follow-up no hygienic problems were present and pain was decreased in all except one patient. All hands could passively be fully opened. In resting position, flexion was seen in the MCP-joints (60 – 90°). Muscle tone was raised in flexors of the wrist and fingers and m. adductor pollicis (Ashworth 1 – 2). Given the same pre- and post-operative circumstances, all patients would agree to have the surgery over again.

Conclusion. Even 19 months after the StP-transfer for clenched fist, all operated hands could still be fully opened and there was a permanent improvement of hygiene and pain reduction.  相似文献   
108.
IntroductionAdult acquired flatfoot deformity (AAFD) caused by posterior tibial tendon dysfunction (PTTD) can lead to the development of peritalar subluxation (PTS) and much more rarely to lateral subtalar dislocation.Presentation of caseA 75-year-old woman was referred to our hospital with an approximately 15-year history of pain in her right foot without obvious trauma. The lateral shifting foot deformity had worsened in the previous 5 years. On presentation, she had tenderness over the talonavicular joint, and the skin overlying the talar head on the medial foot was taut. Imaging revealed lateral displacement of the calcaneus with simultaneous dislocation of the talonavicular and talocalcaneal joints. We diagnosed lateral subtalar dislocation including the talonavicular and talocalcaneal joints caused by PTTD, which we treated by reduction and fusion of the subtalar joint complex. The foot and ankle were immobilized with a cast for 6 weeks.DiscussionAt the 1-year follow-up visit, the patient reported no pain during daily activities, although flatfoot persisted.ConclusionWe report a rare case of chronic lateral subtalar dislocation caused by PTTD that was treated by fusion of the talonavicular and talocalcaneal joints.  相似文献   
109.
110.
A 39‐year‐old woman showed nonsustained polymorphic ventricular tachycardia (PVT) during light physical activity. Cardiac multidetector row computed tomography demonstrated false tendons, one of which proved to be the focus triggering premature ventricular contraction (PVC) in electrophysiological studies. The triggered PVC arose during the diastolic period, which might have caused tension in the false tendon. Radiofrequency catheter ablation targeting the triggered PVC by pace mapping was performed and proved partially effective against PVT. (PACE 2012;35:e341–e344)  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号