Neurophysiological adaptations to spaceflight and simulated microgravity

Changes in physiological functions after spaceflight and simulated spaceflight involve several mechanisms. Microgravity is one of them and it can be partially reproduced with models, such as head down bed rest (HDBR). Yet, only a few studies have investigated in detail the complexity of neurophysiological systems and their integration to maintain homeostasis. Central nervous system changes have been studied both in their structural and functional component with advanced techniques, such as functional magnetic resonance (fMRI), showing the main involvement of the cerebellum, cortical sensorimotor, and somatosensory areas, as well as vestibular-related pathways. Analysis of electroencephalography (EEG) led to contrasting results, mainly due to the different factors affecting brain activity. The study of corticospinal excitability may enable a deeper understanding of countermeasures' effect, since greater excitability has been shown being correlated with better preservation of functions. Less is known about somatosensory evoked potentials and peripheral nerve function, yet they may be involved in a homeostatic mechanism fundamental to thermoregulation. Extending the knowledge of such alterations during simulated microgravity may be useful not only for space exploration, but for its application in clinical conditions and for life on Earth, as well.     

替牙期骨性Ⅲ类单侧完全性唇腭裂患者修复术后口周力的分布特征

目的:通过与同龄非唇腭裂正常 儿童比较,研究替牙期骨性Ⅲ类单侧完全性唇腭裂(unilateral cleft lip and palate,UCLP)患者上下颌不同位点口周力的特征。 方法:选取替牙期6～12岁UCLP患者20例(男14例,女6例)为UCLP组;同龄正常 儿童21例(男14例,女7例)为对照组。采用口周肌压力采集系统测量每个研究对象息止 位时双侧上下颌中切牙、尖牙或乳尖牙、第一前磨牙或乳磨牙、第一恒磨牙的唇颊、舌腭侧龈缘的口周力。使用SPSS 25.0统计软件对数据进行统计分析。 结果:1．UCLP组上颌口周力裂侧大于非裂侧( P<0.05),下颌口周力两侧无差异( P>0.05)。2. UCLP组上颌口周力大于对照组( P<0.05),两组上颌唇颊侧的口周力均在第一前磨牙/乳磨牙区最大,在中切牙区最小。3. UCLP组下颌唇颊侧口周力小于对照组( P<0.01),下颌中切牙舌侧区UCLP组大于对照组( P<0.05)。4. UCLP组上颌牙弓内外口周力差值大于对照组( P<0.05),下颌差值小于对照组( P<0.01)。 结论:替牙期骨性Ⅲ类UCLP患者口周力较同龄非唇腭裂正常 儿童存在异常。     

实时剪切波弹性成像测量女性耻骨直肠肌杨氏模量值

目的比较未育及已育初产妇耻骨直肠肌(PR)静息及最大收缩状态下的杨氏模量值差异。方法未育女性73例(未育组),已育初产妇45例(产后1~6年,已育组),利用剪切波弹性成像(SWE)分别在静息及最大收缩状态下测量PR前部、中部及后部的杨氏模量值,并计算差值,比较两组的差异。结果未育组及已育组双侧PR各部最大收缩状态下的杨氏模量值均较静息状态下增大(P均<0.01)。未育组静息及最大收缩状态下PR各部的杨氏模量值及各部收缩前后变化差值与已育组比较,差异均无统计学意义(P均>0.05)。结论 SWE可以定量评估耻骨直肠肌的弹性功能。未育及已育初产妇PR最大收缩状态下的杨氏模量值均较静息状态下大。在静息状态下、最大收缩状态下及收缩前后杨氏模量变化差值,已育初产妇与未育女性的杨氏模量值无差异,分娩对耻骨直肠肌弹性的影响不大。     

Automatic detection of wakefulness and rest intervals in actigraphic signals: A data-driven approach

Actigraphy is an useful tool for evaluating the activity pattern of a subject; activity registries are usually processed by first splitting the signal into its wakefulness and rest intervals and then analyzing each one in isolation. Consequently, a preprocessing stage for such a splitting is needed. Several methods have been reported to this end but they rely on parameters and thresholds which are manually set based on previous knowledge of the signals or learned from training. This compromises the general applicability of this methods. In this paper we propose a new method in which thresholds are automatically set based solely on the specific registry to be analyzed. The method consists of two stages: (1) estimation of an initial classification mask by means of the expectation maximization algorithm and (2) estimation of a final refined mask through an iterative method which re-estimates both the mask and the classifier parameters at each iteration step. Results on real data show that our methodology outperforms those so far proposed and can be more effectively used to obtain derived sleep quality parameters from actigraphy registries.     

铸造牙间卡用于可摘局部义齿修复

目的:改善铸造可摘局部义齿固位体的美观性,减轻颊侧固位体的异物感。方法:在两基牙间的颊、龈外展隙内设置牙间卡(发夹卡)。结果:固位体金属外露少、隐蔽性好,美观明显改善,同时,体积小,无异物感。对34例不同牙缺失患者的使用,经1~2年观察,修复体固位良好,基牙未见松动和移位。结论:铸造牙间卡在美观、制作和异物感等方面明显优于常规铸造冠外固位体。     

艾灸神阙穴对不同程度力竭运动大鼠海马区单胺类神经递质的影响

目的:探讨艾灸神阙穴对不同程度力竭运动大鼠海马区单胺类神经递质的影响。方法:将72只SD雄性大鼠按随机数字表法分为正常组8只、模型组和艾灸组各32只,根据造模或治疗时间将模型组和艾灸组随机分为1、4、7、10次亚组,每亚组8只,采用游泳实验建立力竭模型。艾灸各亚组大鼠造模后即刻温和灸神阙穴15min,隔日1次,各亚组大鼠完成相应力竭运动后24 h检测海马组织5-HT、DA、NE的含量。结果:与正常组比较,模型各亚组5-HT含量均明显升高,模型1、4、7次亚组NE含量均明显升高,模型1次亚组DA含量明显升高,模型10次亚组却明显降低。与相应模型亚组比较,艾灸4次亚组NE含量明显升高,艾灸7、10次亚组5-HT含量显著降低,DA、NE含量明显升高。结论:艾灸神阙穴可以通过调节反复力竭运动大鼠海马区神经递质,促进神经细胞的功能恢复,改善机体疲劳状态,为今后临床应用提供一定的实验基础。     

吸烟对早期糖尿病肾病静息能量消耗的影响

目的 观察吸烟对早期糖尿病肾病静息能量消耗(REE)的影响及与氧化应激和炎症反应之间的关系.方法 对31例吸烟和40例非吸烟的早期糖尿病肾病患者的一般情况、临床特征、REE、REE与去脂组织(FFM)的比值、氧化应激及炎症反应标志物进行比较分析.结果 吸烟组的REE/FFM比非吸烟组显著增高15.96%(P=0.001).相关分析提示,REE/FFM的增高与吸烟有关(t=0.395,P=0.001).氧化应激标志物丙二醛(MDA)、超氧化物歧化酶(SOD)和炎症反应标志物高敏C反应蛋白(hs-CRP)两组间差异有统计学意义(P＜0.05),脂联素、TNFα组间差异无统计学意义(P＞0.05),REE/FFM的增高与MDA、SOD、hs-CRP、脂联素、TNFα均不相关(P＞0.05).结论 吸烟可导致早期2型糖尿病肾病患者REE增加,引起氧化应激和炎症反应,但REE增高与氧化应激和炎症反应无关.     

养老院内老年性肺炎的病原学调查

目的：探讨养老院内老年性肺炎的病原体分布情况。方法：2005年7月至2006年6月在在养老院内居住的老年性肺炎患者63例,收集痰及发热患者（〉38℃）的静脉血进行培养。抽取患者急性期和间隔2～4周恢复期静脉血,进行肺炎支原体lgMl、gG抗体检查,肺炎衣原体lgMl、gG抗体检查,军团菌lgM抗体和腺病毒lgM抗体检查。病原体阳性临床标准：①合格痰标本培养出优势菌（1株或多株细菌）并呈中度以上生长;合格痰标本少量生长,但与涂片镜检一致;②血培养出有临床意义的病原菌;③恢复期血清肺炎支原体lgM和lgG抗体、肺炎衣原体lgM和lgG抗体、军团菌lgM抗体滴度≥4倍增高或降低。结果：63例均进行血清学检测,59例进行痰培养,19例进行血培养。单一病原体感染顺位前3位：肺炎克雷伯杆菌4例（6.3%）,流感嗜血杆菌4例（6.3%）,肺炎支原体3例（4.8%）及肺炎链球菌3例（4.8%）;2种病原体混合感染顺位前3位：肺炎支原体＋流感嗜血杆菌4例（6.3%）,肺炎支原体＋肺炎克雷伯杆菌3例（4.8%）,流感嗜血杆菌＋嗜肺军团菌（3.2%）及肺炎衣原体＋肺炎克雷伯杆菌2例（3.2%）。结论：养老院内老年性肺炎的病原体以革兰阴性杆菌及革兰阴性杆菌合并非典型病原体的混合感染为主。     

卡介菌多糖核酸治疗小儿咳嗽变异性哮喘

目的：观察卡介菌多糖核酸注射液在小儿咳嗽变异性哮喘治疗应用的疗效。方法：将本科40例咳嗽变异性哮喘患儿，随机分为治疗组和对照组（各20例）。治疗组给予BCG—PSN＋必可酮气雾剂，对照组：给予单用必可酮气雾剂吸入，连续吸入6周，观察疗效，并进行统计学处理。结果：治疗组总有效率为95％，对照组总有效率为70％，统计学处理总有效率有显著差异（P〈O．01）。结论：卡介菌多糖核酸（polysaccharide nucleic acidfraction of BCG，BCG—PSN）能有效地控制咳嗽变异性哮喘（CVA）的呼吸道的反复感染，提高免疫功能；与必可酮配合，能有效地控制CVA的复发。