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   511篇
  免费   31篇
  国内免费   13篇
耳鼻咽喉   9篇
儿科学   6篇
妇产科学   10篇
基础医学   50篇
口腔科学   5篇
临床医学   81篇
内科学   37篇
皮肤病学   1篇
神经病学   69篇
特种医学   21篇
外科学   118篇
综合类   44篇
预防医学   14篇
眼科学   19篇
药学   26篇
中国医学   6篇
肿瘤学   39篇
  2024年   1篇
  2023年   34篇
  2022年   58篇
  2021年   50篇
  2020年   32篇
  2019年   35篇
  2018年   45篇
  2017年   41篇
  2016年   20篇
  2015年   20篇
  2014年   44篇
  2013年   37篇
  2012年   22篇
  2011年   19篇
  2010年   6篇
  2009年   20篇
  2008年   15篇
  2007年   10篇
  2006年   7篇
  2005年   8篇
  2004年   2篇
  2003年   2篇
  2002年   3篇
  2001年   6篇
  2000年   3篇
  1998年   3篇
  1997年   2篇
  1996年   2篇
  1991年   3篇
  1990年   1篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1980年   1篇
排序方式: 共有555条查询结果,搜索用时 0 毫秒
11.
目的探讨多模态技术联合术中唤醒麻醉在Broca区胶质瘤患者语言功能区定位中的作用和手术疗效。方法回顾性分析2011年1月至2017年12月复旦大学附属华山医院神经外科行手术切除的Broca区胶质瘤患者的临床资料,共42例。术前采用功能磁共振成像和弥散张量成像技术重建语言皮质激活区域和皮质下传导通路,术中在唤醒麻醉下通过直接电刺激技术定位语言皮质和皮质下传导通路,并在术中磁共振、实时神经影像导航系统引导下行肿瘤切除。根据肿瘤是否侵犯中央前回腹侧部(vPMC)将患者分为未侵犯vPMC(仅侵犯额下回后部)组24例,侵犯vPMC组18例,评估并比较两组患者语言功能区定位情况和疗效。结果42例患者均完成术中语言功能区定位,34例(81.0%)至少有1个阳性定位点;3例(7.1%)在定位过程中出现癫痫局灶性发作。25例患者肿瘤为全切除,17例为非全切除。术后病理学证实世界卫生组织(WHO)肿瘤分级Ⅱ级者23例,Ⅲ级者14例,Ⅳ级者5例。术后1个月内(近期)16例(38.1%)患者有语言功能障碍,其中12例3个月内恢复,4例(9.5%)未恢复。术后所有患者随访6~84个月(中位数为24个月),14例出现肿瘤进展,其中11例死亡。与未侵犯vPMC组比较,侵犯vPMC组肿瘤的WHO级别高(P=0.011),术后近期语言功能障碍的发生比率高[分别为10/18、25.0%(6/24),P=0.044],无进展生存期[分别为(28.4±5.2)个月、(80.7±3.2)个月]和总生存期[分别为(38.8±5.8)个月、(80.8±3.2)个月]均短。差异均有统计学意义(均P<0.001)。结论多模态技术联合术中唤醒麻醉治疗Broca区胶质瘤有助于在最大化切除肿瘤的同时,保护患者的语言功能。其中肿瘤侵犯vPMC比仅侵犯额下回后部者引起近期语言功能障碍率更高,预后更差。  相似文献   
12.
13.
14.
目的:探讨多模态超声(MUS)对侵袭性前列腺癌(PCa)的诊断价值及受试者工作特征(ROC)曲线分析。方法:选择2018年01月至2021年02月于本院行手术切除并经病理证实的86例PCa患者作为研究对象,根据病理Gleason评分可分为两组,高侵袭组(Gleason>4+3,共46例),低-中侵袭组(Gleason≤4+3,共40例)。所有患者术前均行MUS检查,包括经直肠常规超声(TRUS)、剪切波弹性成像(SWE)、超声造影(CEUS)。比较两组之间各参数的差异,采用ROC曲线分析其对高侵袭组PCa的诊断效能。结果:高侵袭组与低-中侵袭组的TRUS表现显著不同(P<0.05),其中高侵袭组中TRUS主要表现为弥漫性。高侵袭组SWE中SR比值(23.86±13.67)显著高于低-中侵袭组(12.82±11.95),差异具有统计学意义(P<0.05)。高侵袭组的CEUS参数中初始强度、峰值强度显著高于低-中侵袭组(P<0.05),而两组达峰时间、峰值减半时间无显著差异(P>0.05)。MUS对高侵袭组PCa诊断的ROC曲线下面积最大,敏感度、特异度也最高(P<0.05)。结论:MUS对高侵袭性PCa具有更高的诊断价值,有助于指导临床对治疗方案的选择。  相似文献   
15.
16.
17.
《Brain stimulation》2021,14(4):884-894
BackgroundCombining training or sensory stimulation with non-invasive brain stimulation has shown to improve performance in healthy subjects and improve brain function in patients after brain injury. However, the plasticity mechanisms and the optimal parameters to induce long-term and sustainable enhanced performance remain unknown.ObjectiveThis work was designed to identify the protocols of which combining sensory stimulation with repetitive transcranial magnetic stimulation (rTMS) will facilitate the greatest changes in fMRI activation maps in the rat's primary somatosensory cortex (S1).MethodsSeveral protocols of combining forepaw electrical stimulation with rTMS were tested, including a single stimulation session compared to multiple, daily stimulation sessions, as well as synchronous and asynchronous delivery of both modalities. High-resolution fMRI was used to determine how pairing sensory stimulation with rTMS induced short and long-term plasticity in the rat S1.ResultsAll groups that received a single session of rTMS showed short-term increases in S1 activity, but these increases did not last three days after the session. The group that received a stimulation protocol of 10 Hz forepaw stimulation that was delivered simultaneously with 10 Hz rTMS for five consecutive days demonstrated the greatest increases in the extent of the evoked fMRI responses compared to groups that received other stimulation protocols.ConclusionsOur results provide direct indication that pairing peripheral stimulation with rTMS induces long-term plasticity, and this phenomenon appears to follow a time-dependent plasticity mechanism. These results will be important to lead the design of new training and rehabilitation paradigms and training towards achieving maximal performance in healthy subjects.  相似文献   
18.
李怡  何文 《中国卒中杂志》2021,16(11):1183-1188
颈动脉粥样硬化易损斑块与缺血性脑血管事件的发生密切相关。颈动脉超声不仅可以量 化颈动脉狭窄程度,还可以评估颈动脉粥样硬化斑块的易损性。三维超声可定量评估颈动脉粥样硬 化斑块的体积,超声造影可显示斑块内新生血管的密度及分布区域,剪切波弹性成像可测定斑块组 织的硬度,反映斑块不同部位的组织成分。颈动脉超声技术的发展使其在缺血性卒中诊疗领域中的 应用更加广泛,对颈动脉血流动力学和管壁的评价更加精确,有助于临床判断脑血管事件的风险并 进行相应的干预。  相似文献   
19.
20.
AIM: To determine the prevalence of bipolar disorder (BD) and sub-threshold symptoms in children with attention deficit hyperactivity disorder (ADHD) through 14 years’ follow-up, when participants were between 21-24 years old.METHODS: First, we examined rates of BD type I and II diagnoses in youth participating in the NIMH-funded Multimodal Treatment Study of ADHD (MTA). We used the diagnostic interview schedule for children (DISC), administered to both parents (DISC-P) and youth (DISCY). We compared the MTA study subjects with ADHD (n = 579) to a local normative comparison group (LNCG, n = 289) at 4 different assessment points: 6, 8, 12, and 14 years of follow-ups. To evaluate the bipolar variants, we compared total symptom counts (TSC) of DSM manic and hypomanic symptoms that were generated by DISC in ADHD and LNCG subjects. Then we sub-divided the TSC into pathognomonic manic (PM) and non-specific manic (NSM) symptoms. We compared the PM and NSM in ADHD and LNCG at each assessment point and over time. We also evaluated the irritability as category A2 manic symptom in both groups and over time. Finally, we studied the irritability symptom in correlation with PM and NSM in ADHD and LNCG subjects.RESULTS: DISC-generated BD diagnosis did not differ significantly in rates between ADHD (1.89%) and LNCG 1.38%). Interestingly, no participant met BD diagnosis more than once in the 4 assessment points in 14 years. However, on the symptom level, ADHD subjects reported significantly higher mean TSC scores: ADHD 3.0; LNCG 1.7; P < 0.001. ADHD status was associated with higher mean NSM: ADHD 2.0 vs LNCG 1.1; P < 0.0001. Also, ADHD subjects had higher PM symptoms than LNCG, with PM means over all time points of 1.3 ADHD; 0.9 LNCG; P = 0.0001. Examining both NSM and PM, ADHD status associated with greater NSM than PM. However, Over 14 years, the NSM symptoms declined and changed to PM over time (df 3, 2523; F = 20.1; P < 0.0001). Finally, Irritability (BD DSM criterion-A2) rates were significantly higher in ADHD than LNCG (χ2 = 122.2, P < 0.0001), but irritability was associated more strongly with NSM than PM (df 3, 2538; F = 43.2; P < 0.0001).CONCLUSION: Individuals with ADHD do not appear to be at significantly greater risk for developing BD, but do show higher rates of BD symptoms, especially NSM. The greater linkage of irritability to NSM than to PM suggests caution when making BD diagnoses based on irritability alone as one of 2 (A-level) symptoms for BD diagnosis, particularly in view of its frequent presentation with other psychopathologies.  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