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41.
Organ spectrophotometry has been applied to analyze cytochrome redox changes in brain slice preparations. An interface-chamber method for maintaining metabolism of brain slice tissues was devised to reduce noise on recording traces of spectrophotometric signals, and then used for continuous monitoring and simultaneous recording of electrical and optical signals from brain slices. With this method, the noise level during the recording of redox states of cytochromes was decreased to 0.0004 A unit. 相似文献
42.
Martin Griebe Michael Daffertshofer Mark Stroick Magdalena Syren Parviz Ahmad-Nejad Michael Neumaier Juergen Backhaus Michael G. Hennerici Marc Fatar 《Neuroscience letters》2007
Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool. 相似文献
43.
A finite element model of the steady state temperature distribution in the human torso is developed. The torso is approximated by a circular cylinder of core surrounded by a layer of muscle and insulating layers of fat and skin. The model is simplified by neglecting longitudinal heat flow. The region occupied by a circular cross-section of the torso is discretized into a mesh of triangles and the boundary of the torso, that is, the skin surface, is consequently approximated by a polygon. The elliptic partial differential equation governing the steady state temperature distribution, together with the associated boundary conditions, are expressed in equivalent variational form. Linear basis functions are used and the resulting integral is minimized over the region bounded by the approximating polygon. Results for two numerical experiments are determined by solving systems of linear equations. 相似文献
44.
目的 探讨渐进性肌肉放松训练配合心理干预对艾滋病患者服药依从性及心理状态的影响。方法 选择2017年8月—2020年8月于本院就诊的68例艾滋病患者,按随机数字表法分为对照组和观察组,每组34例。对照组实施常规护理干预,观察组在此基础上实施渐进性肌肉放松训练配合心理干预,比较两组服药依从性及医院焦虑抑郁量表(HospitalAnxietyand Depresseo Scale,HAD)评分。结果 观察组服药总依从率为97.06%,高于对照组的70.59%,(χ2=8.785,P=0.003);观察组干预2周后焦虑评分为(14.35±1.67)分、抑郁评分为(13.98±1.38)分,均低于对照组的(15.63±1.59)分、(15.08±1.27)分,(t=3.237、3.420,P=0.002、0.001)。结论 渐进性肌肉放松训练配合心理干预应用于艾滋病患者,能够提高患者服药依从性,改善患者心理状态。 相似文献
45.
Katharina Voigt Emily Giddens Romana Stark Emma Frisch Neda Moskovsky Naomi Kakoschke Julie C. Stout Mark A. Bellgrove Zane B. Andrews Antonio Verdejo-Garcia 《Nutrients》2021,13(6)
Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours. 相似文献
46.
ObjectivesA number of studies have shown an association between smoking habit and quality of life, but these have mainly involved cross-sectional data. This study takes advantage of longitudinal panel data to estimate the effect of the transition from “smoker” to “ex-smoker” status (smoking cessation) on health-related quality of life (HRQoL), measured by SF-36, in an Australian general population sample.MethodsPanel data from 13 waves (2001-2013) of a nationally representative longitudinal survey of Household Income and Labour Dynamics of Australia (HILDA) were used; 1858 respondents (5% of total HILDA sample) who experienced only 1 cessation event in their HILDA life were selected. HRQoL trajectories elicited by SF-36 (0-100 scale, worst to best health) were modeled before and after cessation events using a piecewise (segmented) 2-way fixed-effect linear regression, adopted to capture within-person differences. This enabled measurement of changes of regression slopes and intercept while controlling time-invariant characteristics (eg, country of birth, gender) and time-varying changes in health status.ResultsAnnual pre-post intervention improvements were estimated for the following dimensions: role physical 0.65 (95% CI 0.62-1.24), bodily pain 0.48 (95% CI 0.10-0.86), general health 0.55 (95% CI 0.2-0.9), and the physical component summary score 0.22 (95% CI 0.01-0.04). Immediate effects (discontinuity at the time of cessation) of smoking cessation existed for bodily pain –1.5 (95% CI –2.52 to –0.40) and general health 1.82 (95% CI 1.01-2.62). The effects for mental health domains were not significant.ConclusionsAdjusting for all unmeasured time-invariant confounders and controlling the effect of time, this study revealed the varied effects of smoking cessation on HRQoL; it has positive effect on physical and general health but nonsignificant effect on mental aspects. Preference-based utility measures based on SF-6D capture changes that can be measured in several of the domains of the SF-36. 相似文献
47.
在聚合物固体电解质(聚乙二醇不饱和聚酯网络-LiClO4)中进行吡咯聚合原位制得了聚吡咯/聚合物固体电解质双层复合膜。用扫描电镜观察复合膜的界面结构,用循环伏安和交流阻抗法研究了复合膜的电化学杂脱掺杂性能。结果表明,聚吡咯/聚合物固体电解质双层复合膜具有相互穿插渗透的固/固密接界面结构,这种界面结构改善了聚吡咯和聚俣物固体电解质间的界面接触,提高了聚吡咯在聚俣物固体电解质中的电化学掺杂脱掺杂性能。 相似文献
48.
The gold-standard method for diagnosing arteriogenic erectile dysfunction (AED) is the penile Doppler ultrasonography. We proposed a novel method for predicting AED using ultrasonic shear wave elastography (SWE) considering that the former was invasive and variable. A total of 98 male patients were enrolled in our study, referred for ED between December 2018 and October 2020. For comparison, we also included 42 volunteers from the Healthy Physical Examination Center of our hospital. The Penile Doppler Ultrasonography (PDU) and SWE were performed for all patients with the intracavernosal injection (ICI). We named three groups as AED group, nonvascular ED group and healthy controls group. No statistically significant differences were found among the three groups in terms of demographic and clinical characteristics. There were no significant differences in IIEF-5 between AED and nonvascular ED. A significant (r = 0.642, p < 0.0001) positive correlation between flaccid and erectile SWE was observed. With a cut-off value of 13.45 KPa, the area under curve, specificity, and sensitivity of the SWE values under the flaccid state in distinguishing AED from healthy subjects were 0.867, 0.786 and 0.896 respectively. The SWE value in the flaccid state can distinguish the AED from healthy subjects. 相似文献
49.
50.
择业期间大学生焦虑水平及其影响因素 总被引:16,自引:0,他引:16
目的 :对择业期间大学生焦虑水平及其影响因素进行调查 ,为高校心理卫生工作提供科学依据。方法 :采用“状态—特质焦虑量表”对 5 2 2名大学生择业期间焦虑水平进行测查 ,采用问卷调查法及访谈法探讨影响择业期间大学生焦虑水平的因素。结果 :择业情境导致大学生焦虑水平普遍升高 ,部分学生呈过度焦虑状态。择业期间大学生焦虑水平受自身条件、个人理想、社会环境、学校教育、家庭期望等因素的综合影响 ,其中自身条件、个人理想为首要因素。结论 :择业期间大学生产生焦虑的根本原因在于职业理想与实现可能的矛盾冲突 相似文献