Permanent endovenous pediatric pacing: absence of lead failure--20 years follow-up study

Background: The aim of the study was to analyze endovenous pacing lead survival in pediatric population implanted by cephalic cut down, or by axillary vein puncture.
Methods: All implantations were performed in total endotracheal anesthesia, by the same surgeon. Implantations of ventricular leads were performed by cephalic vein cut down or by external jugular vein preparation. In dual-chamber pacing, atrial leads were implanted via cephalic vein (along with ventricular lead), by axillary vein puncture or via external jugular vein. All implanted leads were secured by resorbable suture.
Results: Over the 20-year follow-up period, 105 children of 5.7 years average age (range 1 day–15 years) were implanted with a permanent endovenous pacing system for congenital or postsurgical complete atrioventricular block or sinus node disease. Within the group, 27 patients (25.7%) weighed less than 10 kg on implantation. A total of 121 endovenous leads were implanted. All ventricular leads were with a passive fixation mechanism, and most of them unipolar (87.6%) and steroid eluting (94.2%). Leads implanted in atrial position were 82% bipolar, predominantly with active fixation (94%), and all steroid eluting. The most frequently used mode of stimulation was VVIR (66.6%). No acute or chronic lead displacement, exit block, sensing problem, lead conductor fracture, insulation defect or infections were observed during the total follow-up of 709 pacing years (average 6.9, range 0–20 years).
Conclusion: Implantation of the endovenous leads by preparation of the cephalic or puncture of the axillary vein, with lead fixation by resorbable suture represents a method of choice.     

HPLC法测定小儿消退糖浆中大黄酚含量

[目的]建立以高效液相色谱法测定小儿消退糖浆中的大黄酚含量的方法.[方法]色谱为C18色谱柱(4mmx250mm,5μm),流动相为甲醇-水-磷酸-戊烷磺酸钠(80:20:0.1:0.1),流速1.0 mL/min,检测波长为254 am,柱温为室温.[结果]大黄酚检测浓度在5～25 mg/L范围内与峰面积值线性关系良好(r=0.999 9),平均回收率为100.13%(RSD=1.1%).[结论]本方法可用于消食退热糖浆的质量检测.     

Parallel input makes the brain run faster

In serial sensory processing, information flows from the thalamus via primary sensory cortices to higher-order association areas. However, association cortices also receive, albeit weak, direct thalamocortical sensory inputs of unknown function. For example, while information proceeds from primary (SI) to secondary (SII) somatosensory cortex in a serial fashion, both areas are known to receive direct thalamocortical sensory input. The present study examines the potential roles of such parallel input arrangements. The subjects were presented with median nerve somatosensory stimuli with the instruction to respond with the contralateral hand. The locations and time courses of the activated brain areas were first identified with magnetoencephalography (MEG). In a subsequent session, these brain areas were modulated with single-pulse transcranial magnetic stimulation (TMS) at 15-210 ms after the somatosensory stimulus while electroencephalography (EEG) was recorded. TMS pulses at 15-40 ms post-stimulus significantly speeded up reaction times and somatosensory-evoked responses, with largest facilitatory effects when the TMS pulse was given to contralateral SII at about 20 ms. To explain the results, we propose that the early somatosensory-evoked physiological SII activation exerts an SII-->SI influence that facilitates the reciprocal SI-->SII pathway - with TMS to SII we apparently amplified this mechanism. The results suggest that the human brain may utilize parallel inputs to facilitate long-distance cortico-cortical connections, resulting in accelerated processing and speeded reaction times. This arrangement could also allow very early top-down modulation of the bottom-up stream of sensory information.     

Ⅱ级安全柜垂直下降气流速度的数值模拟优化

国家标准YY-0569中规定Ⅱ级生物安全柜下降气流平均速度为0．25～0．5m／s，前窗流入气流平均流速应不低于0．5m／s，本文通过CFD软件对这个速度范围是否会产生外溢进行气流模拟，经数据分析得出了更优的气流速度范围为0．25—0．405m／s。     

Social reasoning skills in adults with Down syndrome: the role of language,executive functions and socio‐emotional behaviour

Background Although the prevalence of mental illness and behaviour problems is lower in adults with Down syndrome (DS) than in other populations with intellectual disabilities, they do present emotional and relational problems, as well as social integration difficulties. However, studies reporting on specific competences known to be central in developing appropriate social relationships (e.g. social reasoning, emotion processing, theory of mind) remain rare in the adult DS population and the mechanisms underlying these people's emotional and relational difficulties are unclear. Method The present study investigated the ability to understand the appropriateness of others' social behaviour in 34 adults with DS, using the Social Resolution Task (SRT). Their results were compared with those of 34 typically developing (TD) children matched for gender and receptive vocabulary. The relationships among the SRT experimental task, cognitive competences (receptive and productive vocabulary, non‐verbal reasoning, inhibition, selective attention) and a caregiver‐rated measure of socio‐emotional behaviour were examined in the DS group. Results The DS participants' global SRT scores did not differ from those of the controls. However, analyses of the SRT subscores revealed that the DS group identified significantly fewer inappropriate situations than the control group. Nevertheless, when they correctly identified the behaviour as inappropriate, they were as well as the controls to explain the rules underlying their responses. Regression analyses showed that receptive vocabulary and selective attention and a specific dimension of the socio‐emotional profile (social relating skills) constituted the best predictors of the DS adults' performance on the SRT. Conclusions The main findings show that the DS participants demonstrate relatively good social reasoning skills in comparison with TD children matched for verbal age. However, the two groups present distinctions in their response patterns, and the influence of cognitive variables on success on the SRT also appears different. While selective attention skills are found to be significant predictors for both groups, the influence of receptive vocabulary level is much stronger in the DS group. The implications of particular cognitive and socio‐emotional factors for success on the SRT in this group are considered in more detail.     

用跳台法和避暗法观察药物对学习和记忆获得的影响

采用跳台和避暗法，观察康维命（ＣＶＭ）对小鼠学习和记忆获得的影响。结果表明，ＣＶＭ能提高小鼠的学习和记忆获得能力。两种方法均可用于促进学习记忆试验新药品的筛选，跳台法可观察对学习和记忆获得的影响，避暗法仅可观察对记忆获得的影响     

An extension of the continual reassessment method using decision theory.

The primary goal of a phase I trial is to find the maximally tolerated dose (MTD) of a treatment. The MTD is usually defined in terms of a tolerable probability, q(*), of toxicity. Our objective is to find the highest dose with toxicity risk that does not exceed q(*), a criterion that is often desired in designing phase I trials. This criterion differs from that of finding the dose with toxicity risk closest to q(*), that is used in methods such as the continual reassessment method. We use the theory of decision processes to find optimal sequential designs that maximize the expected number of patients within the trial allocated to the highest dose with toxicity not exceeding q(*), among the doses under consideration. The proposed method is very general in the sense that criteria other than the one considered here can be optimized and that optimal dose assignment can be defined in terms of patients within or outside the trial. It includes as an important special case the continual reassessment method. Numerical study indicates the strategy compares favourably with other phase I designs.     

清开灵滴丸对家兔感染性退热作用的研究

目的：为进一步确定清开灵滴丸对家兔感染性发热的退热效果。方法：选用新西兰大耳白家兔56只，分7组，设对照、比较、观察3组，测出每只家兔基础体温，用伤寒、副伤寒甲乙三联茁液静脉注射致热。观察组分别灌服清开灵滴丸水溶液，依次在30、60、120、180、240和300min时测出每只家兔体温，按组记录。结果：家兔致热前后体温对比差异有显著性(P＜0．01)，灌服清开灵滴丸前后体温比较差异有非常显著性(P＜0．01)，各给药组体温与对照组相应时间的体温比较差异有非常显著性(P＜0．01)。结论：清开灵滴丸对家兔感染性发热有明显的退热作用。