牵张成骨修复下颌骨缺损组织学研究

目的探讨牵张成骨修复兔下颌骨缺损时骨组织再生的组织学改变。方法选取25只成年健康家兔，并随机分为实验组（20只）和对照组（5只），分别行一侧下颔骨缺损牵张成骨术，实验组在牵张第4、8天及固定期第1、3、5周，分别处死4只兔子，对照组在相应时间分别处死1只兔子，均取骨组织标本并观察其组织学改变。结果牵张第4、8天实验组家兔牵张区均为纤维结缔组织，并存在成纤维细胞，骨基质周缘可见大量活跃增生的成骨细胞；固定期第1、3周牵张区两端可见大量新骨形成，但中间仍为纤维结缔组织，新形成的骨组织表面始终附着大量活跃增生的成骨细胞，成行或以复层排列：固定期5周，成骨细胞明显减少，并逐渐呈现出哈佛系统。在整个观察过程中对照组截骨间隙处的成骨过程与一般的骨折愈合情况类似，以软骨化骨为主。结论牵张成骨修复下颌骨缺损以膜内成骨为主，同时辅以少量的软骨化骨。     

A comparison of the effects of preferred music, arithmetic and humour on cold pressor pain.

Research studies of 'audioanalgesia', the ability of music to affect pain perception, have significantly increased in number during the past two decades. Listening to preferred music in particular may provide an emotionally engaging distraction capable of reducing both the sensation of pain itself and the accompanying negative affective experience. The current study uses experimentally induced cold pressor pain to compare the effects of preferred music to two types of distracting stimuli found effective within the previous studies; mental arithmetic, a cognitive distraction, and humour, which may emotionally engage us in a similar manner to music. Forty-four participants (24 females, 20 males) underwent three cold pressor trials in counterbalanced order. The Paced Auditory Serial Addition Task provided the cognitive distraction and a choice was given from three types of audiotaped stand-up comedy. Participants provided their own preferred music. A circulating and cooling water bath administered cold pressor stimulation. Tolerance time, pain intensity on visual analogue scale and the pain rating index and perceived control were measured. Preferred music listening was found to significantly increase tolerance in comparison to the cognitive task, and significantly increase perceived control in comparison to humour. Ratings of pain intensity did not significantly differ. The results suggest preferred music listening to offer effective distraction and enhancement of control as a pain intervention under controlled laboratory conditions.     

渐进抗阻结合肌电反馈电刺激训练法对偏瘫后肌力恢复的影响

目的通过对比实验来探讨渐进抗阻结合肌电反馈电刺激训练法对偏瘫后肌力恢复的影响,以期为偏瘫后肌力恢复训练的结合疗法提供一定的依据。方法将20名脑血管意外的患者分为两组（结合组和非结合组,每组10例）,分别进行单一肌力训练（渐进抗阻训练法）和结合肌力训练法（渐进抗阻和肌电反馈电刺激训练法结合）,进行3个疗程（2周一个疗程）训练后,对患者的肌力进行测量与评估。结果实验前两组患者肌力和做功差异无统计学意义（P〉0.05）,实验后两训练组肌力和做功都有一定的提高,但是结合组肌力和做功提高幅度明显高于非结合组（P〈0.01）。结论渐进抗阻练习结合肌电反馈电刺激训练法是一种有效的偏瘫患者肌力恢复的结合疗法。     

“渐处理”对肺缺血再灌注损伤的保护作用

目的探讨＂渐处理＂作为一种改良的后处理方式对大鼠肺缺血再灌注损伤的保护作用及其机制。方法采用大鼠肺原位缺血再灌注损伤模型进行研究。将40只清洁级SD大鼠随机分为四组：手术对照组（S组）,缺血再灌注组（I/R组）,缺血后处理组（IPO组）,缺血后渐处理组（IGR组）。观察肺组织病理形态变化,测定肺组织湿/干重比（W/D）,检测肺组织匀浆中丙二醛（MDA）含量及超氧化物歧化酶（SOD）活性。结果与S组比较,I/R组光镜下见肺组织病变明显加重,肺组织W/D明显增加,肺组织中SOD活力明显降低,MDA的浓度明显增高（P〈0.01）;与I/R组比较,IPO组及IGR组肺组织病变减轻,肺组织W/D明显降低,肺组织中SOD活力明显升高,MDA的浓度明显降低（P〈0.01）;IGR组与IPO组比较,上述各项指标均有所减轻,两者差异无统计学意义（P〉0.05）。结论 ＂渐处理＂对大鼠肺原位缺血再灌注损伤有保护作用。与缺血后处理比较,是一种更有效的、更适合临床应用的、减轻再灌注损伤的方法。     

The allocation of attention in displays with simultaneously presented singletons

In an ERP experiment, we investigated whether a ‘permanent’ salient distractor changes the deployment of attention to target and nontarget singletons. Observers searched for a color target in a search array that mainly consisted of black vertical lines, but also always contained a line in a task-irrelevant color. Together with this distractor, a target or nontarget singleton was presented. Nontargets could be salient on the task-relevant dimension (color), or on a neutral dimension (line orientation). N2pc amplitude was maximal for targets, no N2pc was elicited by color nontargets, and orientation nontargets elicited an inverse N2pc. Targets and color nontargets elicited larger N2 amplitude than orientation singletons. P3 amplitude was high for relevant and low for irrelevant singletons. Targets also elicited higher reaction times and more errors. Attention seemed thus driven by the target feature, and by its feature dimension, even when constant distraction on that dimension had to be suppressed.     

The effect of non-visual working memory load on top-down modulation of visual processing

While a core function of the working memory (WM) system is the active maintenance of behaviorally relevant sensory representations, it is also critical that distracting stimuli are appropriately ignored. We used functional magnetic resonance imaging to examine the role of domain-general WM resources in the top-down attentional modulation of task-relevant and irrelevant visual representations. In our dual-task paradigm, each trial began with the auditory presentation of six random (high load) or sequentially ordered (low load) digits. Next, two relevant visual stimuli (e.g., faces), presented amongst two temporally interspersed visual distractors (e.g., scenes), were to be encoded and maintained across a 7-s delay interval, after which memory for the relevant images and digits was probed. When taxed by high load digit maintenance, participants exhibited impaired performance on the visual WM task and a selective failure to attenuate the neural processing of task-irrelevant scene stimuli. The over-processing of distractor scenes under high load was indexed by elevated encoding activity in a scene-selective region-of-interest relative to low load and passive viewing control conditions, as well as by improved long-term recognition memory for these items. In contrast, the load manipulation did not affect participants’ ability to upregulate activity in this region when scenes were task-relevant. These results highlight the critical role of domain-general WM resources in the goal-directed regulation of distractor processing. Moreover, the consequences of increased WM load in young adults closely resemble the effects of cognitive aging on distractor filtering [Gazzaley, A., Cooney, J. W., Rissman, J., & D’Esposito, M. (2005). Top-down suppression deficit underlies working memory impairment in normal aging. Nature Neuroscience 8, 1298-1300], suggesting the possibility of a common underlying mechanism.     

硫酸钙人工骨对山羊下颌骨牵引成骨的影响

目的建立山羊双侧下颌骨牵张成骨实验动物模型,探讨硫酸钙人工骨对山羊下颌骨牵引成骨区新骨生成的作用及局部使用硫酸钙对血清总钙的影响。方法8只山羊随机分为A组（硫酸钙组）和B组（对照组）．建立牵引成骨（Distraction Osteogenesis,DO）模型。A组预牵开3mm间隙,注入硫酸钙人工骨;B组常规牵引：两组均于术后第5天开始,以0．5mm／12h的速度牵引,A组连续牵引7d,B组连续牵引10d,两组颌骨总延长距离均达到10mm。术前及术后早期检测血清碱性磷酸酶（ALP）和血清总钙浓度。牵引结束后第6周取材,对新生骨大体标本、影像学、组织学、骨密度及生物力学等指标进行观察检测。结果所有山羊下颌骨均延长了约10／mm,A组血清ALP浓度、新生骨小梁面积百分比、骨密度及三点弯曲断裂最大载荷值均比B组高（P〈0．05）,而血清总钙浓度与B组相比差别无显著性（P〉0．05）。结论动物实验表明,硫酸钙人丁骨在牵引成骨的早期对新骨的形成具有促进作用．且局部应用硫酸钙对血清总钙浓度无明显影响．具有良好的生物相容性。     

The influence of emotion-focused rumination and distraction on depressive symptoms in non-clinical youth: A meta-analytic review

This review examined evidence for some core predictions of the response styles theory (RST) concerning the relation between response styles and symptoms of depression and gender differences in the use of response styles in non-clinical children and adolescents. In summarizing the literature, effect sizes (pooled correlation coefficients) were calculated for cross-sectional and longitudinal studies. Stability of the obtained effect sizes was evaluated by means of a fail-safe N analysis. Results indicated that stable and significant effect sizes were found for rumination being associated with concurrent and future levels of depression. When controlling for baseline levels of depression, effect sizes for rumination and distraction were not stable, indicating that these findings should be interpreted with considerable caution. Finally, significant and stable effect sizes for gender differences in response styles were found only for rumination among adolescents. Taken together, the findings partly support the predictions of the response styles theory examined in this meta-analysis and may implicate that rumination is a cognitive vulnerability factor for depressive symptoms among adolescents.     

Orthodontic Treatment of an Ankylosed Maxillary Central Incisor through Osteogenic Distraction

Tooth ankylosis is one of the various problems in dentistry and requires special treatment approaches for satisfactory results. In the orthodontic treatment of an ankylosed tooth, different treatment modalities have been put into practice including both orthodontic and orthodontic-surgical approaches. For favorable results, gingival margin esthetics must be considered as much as leveling the ankylosed tooth in the arch. Distraction osteogenesis accompanied by orthodontic mechanics is a sensible way of achieving this goal. However, devices used in the distraction protocol are high in price and bulky in shape, causing functional and esthetic problems for the patient. This report describes treatment of an infrapositioned ankylosed incisor with continuous distraction forces produced by conventional orthodontic mechanics. In conclusion, the ankylosed tooth was leveled in the upper arch successfully with a harmonic gingival margin.