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991.
Sleep disturbance is prevalent in anxious youth and prospectively predicts poor emotional adjustment in adolescence. Study 1 examined whether anxiety treatment improves subjective and objective sleep disturbance in anxious youth. Study 2 examined whether a sleep intervention called Sleeping TIGERS can further improve sleep following anxiety treatment. Study 1 examined 133 youth (ages 9–14; 56% female; 11% ethnic/racial minority) with generalized, social, or separation anxiety over the course of anxiety treatment (cognitive behavioral treatment or client-centered treatment). Sleep-related problems (parent-, child-report) and subjective (diary) and objective (actigraphy) sleep patterns were assessed across treatment in an open trial design. Study 2 included 50 youth (ages 9–14; 68% female; 10% ethnic/racial minority) who continued to report sleep-related problems after anxiety treatment and enrolled in an open trial of Sleeping TIGERS. Pre- and postassessments duplicated Study 1 and included the Focal Interview of Sleep to assess sleep disturbance. Study 1 demonstrated small reductions in sleep problems and improvements in subjective sleep patterns (diary) across anxiety treatment, but outcomes were not deemed clinically significant, and 75% of youth stayed above clinical cutoff. Study 2 showed clinically significant, large reductions in sleep problems and small changes in some subjective sleep patterns (diary). Anxiety treatment improves, but does not resolve, sleep disturbance in peri-pubertal youth, which may portend risk for poor emotional adjustment and mental health. The open trial provides preliminary support that Sleeping TIGERS can improve sleep in anxious youth to a clinically significant degree.  相似文献   
992.
如何从脑电信号中快速准确地识别出P300成分是脑-机接口研究中的一个热点问题.针对P300的识别问题,我们提出了一种将F-score特征选择与支持向量机相结合的判别方法,该方法采用F-score特征选择减少输入特征的维数,以克服支持向量机算法判别速度慢的缺点;然后借助支持向量机算法良好的分类性能实现P300的识别.本文在BCI Competition 2003的P300实验数据集上对该方法进行了验证,结果表明,在5次重复实验中该方法的识别准确率达到了100%,且判别速度与未经特征选择的传统支持向量机算法相比提高了近2倍.  相似文献   
993.
穿戴式呼吸感应体积描记用于睡眠呼吸事件检测   总被引:2,自引:0,他引:2  
可穿戴式呼吸感应体积描记(背心式RIP)系统是我们根据呼吸感应体积描记技术的基本原理研发的一种可穿戴、低负荷的呼吸监测系统.在实现通气量无创测量的基础上,我们将该系统用于睡眠期呼吸事件检测,将该系统与多导睡眠图仪(PSG)对9例疑似睡眠呼吸暂停低通气综合症(SAHS)病人和7名健康男性志愿者进行同步对照检测与分析.通过对比实验,根据背心式RIP系统发生呼吸事件的特征性变化,提出了背心式RIP系统判别呼吸事件的规则.依据该规则,所有经背心式RIP系统诊断为SAHS患者的结果与PSG的诊断结果完全一致,背心式RIP系统检测呼吸事件的敏感性为97.8%,特异性为95.8%,实验结果表明背心式RIP系统能够可靠地检测出睡眠呼吸事件.由于其低生理、心理负荷特性,不需要佩带口鼻气流传感器,可用于家庭环境下、自然睡眠过程的睡眠呼吸紊乱性疾病的诊断.  相似文献   
994.
鉴于热休克蛋白90β(hsp90β)基因内含子中含有维生素D3受体(VDR)结合位点,为探讨作为核受体家族成员的VDR是否对核受体特异分子伴侣的hsp90β基因的表达具有调控作用,我们开展了本项研究。分别将野生型VDR、含N端(1~133氨基酸残基)及C端(281~427氨基酸残基)片段的VDR突变体真核表达质粒与人hsp90β基因调控片段(-1039/+1531)介导的氯霉素乙酰基转移酶(CAT)报告基因质粒共转染Jurkat细胞,检测正常及经热休克(42℃,1h)处理后细胞裂解液中CAT活性。结果表明VDRN端增强、而C端抑制hsp90β的组成性表达;在热诱导条件下野生型VDR对hsp90β的表达有一定的抑制作用,而其C端片段的抑制较强。为进一步研究VDR对细胞内源性热休克基因表达的影响,我们用RTPCR方法研究了VDR的对细胞内hsp90β基因mRNA水平的影响,发现VDR过表达对hsp90β的热诱导表达明显抑制。结果提示VDR对hsp90β基因的组成性和热诱导表达的调控机制不同。  相似文献   
995.
应用单克隆抗体免疫组化染对50例乳腺癌冰冻组织进行转铁蛋白受体与间质个核细胞亚群的关系进行观察,结果显示:(1)乳腺癌间质浸润的MNC各亚群T细胞最多;(2)TrfR阳性组,导管浸润癌或组织学Ⅰ-Ⅱ级乳腺癌间质MNC较单纯癌,不典型髓样癌或组织学Ⅲ级为多,而在TrfR阴性组,组织学Ⅱ级乳腺癌的T细胞,巨噬细胞及NK细胞数多于组织学Ⅰ级病例;(3)TrfR阴性乳腺癌中,LeuB^+1细胞在瘤体≤2c  相似文献   
996.
Bone marrow-derived macrophages from normal and burned rats were cultured for one and four days in the presence of LPS, PHA, or opsonized zymosan as activators, and the supernatants were assayed for the inflammatory mediators TNF, IL-6, and PGE2 and the cells assayed for cytotoxicity. The macrophages responded differently to the various stimuli regarding cytotoxicity and the production of mediators, perhaps implicating the complement receptor CR1 in TNF production and the LPS receptor CD14 or the PHA lectin receptor in IL-6 and PGE2 production and for cytotoxicity. The response of the cells also depended on culture time and postburn time; in addition, macrophages from burned and unburned animals responded differently, depending on postburn day and the type of stimulus. TNF production was generally higher for one-day compared to four-day cultures (i.e., TNF was disappearing in the cultures), but IL-6 and PGE2 production was greater in four-day cultures. The results of this study suggest that thermal injury can contribute to the development of inflammatory and cytotoxic macrophages from bone marrow progenitor cells.  相似文献   
997.
A rare benign condition of uncertain etiology and pathogenesis, Synovial Chondromatosis (SC) is most often seen intraarticularly in adults but only a handful of cases have been reported extraarticularly in children. Symptoms and physical signs consist of pain, swelling, and osteoarthritic changes related to a mass effect. Here we discuss the case of a 9-year-old boy with documented SC of the knee and critically review the Epidemiology, Clinical Presentation, Gross Anatomy and Microscopic Histopathologic Features as well as the role of Imaging Studies in Diagnosis. In addition, this paper reviews Current Pathogenetic Concepts including the infrequent but distinct possibility of malignant transformation.  相似文献   
998.
BACKGROUND AND PURPOSE: Aeromonas spp. often cause infections in immunocompromised patients. To specifically understand the clinical features of Aeromonas bacteremic adults with hematologic malignancies, we investigated the demographic, clinical and microbiologic characteristics of Aeromonas bacteremia in this patient population. METHODS: Retrospective study performed in a tertiary medical center in southern Taiwan, in which adults with hematologic malignancies suffered from Aeromonas bacteremia admitted between 1995 and 2003 were included for study. RESULTS: There were 45 episodes of Aeromonas bacteremia in 41 adults with hematologic malignancies. Episodes of Aeromonas bacteremia which occurred at least 2 months apart were counted as separate cases in the analysis. A total of 30 men and 15 women (mean age: 53.2 years), with 4 patients experiencing 2 episodes, was included. The 3 leading underlying hematologic malignancies were acute myelogenous leukemia (37.8%), myelodysplastic syndrome (26.7%) and non-Hodgkin's lymphoma (17.8%). No cluster of Aeromonas bacteremia was found during the study period. Twenty nine (64.4%) of the 31 patients with nosocomial Aeromonas bacteremia had received recent antineoplastic chemotherapy. The 3 leading clinical manifestations were fever (88.9%), septic shock (40%), and altered consciousness (26.7%). Eleven (24.4%) episodes of bacteremia were polymicrobial. Sixteen (35.6%) patients died within 14 days of onset of bacteremia. The mean duration from sampling blood for culture to death was 3.81 days. Altered consciousness (odds ratio, 8.999; 95% confidence interval, 1.787-45.33; p=0.008) was the only independent prognostic factor for mortality. High resistance rates (11.1% to piperacillin and 35.6% to imipenem) among Aeromonas isolates were also noted. CONCLUSION: In febrile patients with hematologic malignancies and suspected Aeromonas infections, particular attention to the development of alteration of consciousness is needed as it is an independent risk factor for mortality.  相似文献   
999.
将荧光标记的自身红细胞注入SD大鼠体内,在荧光显微镜下观测标记红细胞在大鼠微血管中的流动情况,并通过显微摄像系统将整个过程以视频信号的形式存贮。使用视频采集卡将流速变化过程回放采样,得到暗视场下的荧光图像。然后利用帧图像分离出奇偶场的图像分析方法测定血流速度。在该系统下测量流动小室中荧光小球的流速,得到的测量值与实际值之间的误差小于7%,两者没明显的差异(P>0.05),流速测量的上限为9.6mm/s。并在大鼠微循环障碍研究中,应用此系统得到了血流速度随时间变化的情况。  相似文献   
1000.
Chung YC  Chiu YH  Wu YW  Tao YT 《Biomaterials》2005,26(15):2313-2324
Several phospholipid-based disulfide molecules were synthesized and attached onto the gold-coated silicon wafer using the self-assembling method. The syntheses of these surface-modifying agents were conducted by introducing bromoethylphosphorate (PBr), phosphorylcholine (PC) or phosphorylethanolamine (PE) groups on the terminals of a dialkyl disulfide. After disulfides adsorption onto gold substrate surfaces, the composition, the film thickness, and the conformational order of self-assembled monolayer surfaces were explored and discussed in detail based on reflection-absorption infrared spectroscopy, contact angle measurement, Auger electron spectroscopy, X-ray photoelectron spectroscopy, and so on. The monolayer having the PBr end group could also be converted to a PC surface by treating with trimethylamine. The model functional surfaces of Au-SC11-PC, -PE, -PBr, -OH or corresponding mixed layers were used to mimic biomembrane surfaces. The monolayer having PC groups was found to reduce fibrinogen adsorption as evaluated from protein adsorption experiments using quartz crystal microbalance. It also showed relatively low platelet adherence compare to the glass, PBr and PE surfaces. The cell viability test also revealed that the PC surface displayed lower cytotoxicity than other surfaces.  相似文献   
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