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51.
We examined two recently developed measures of positive automatic thought, the Positive Automatic Thoughts Questionnaire (ATQ-P) and the Automatic Thoughts Questionnaire—Revised (ATQ-RP). Internal consistency, concurrent validity, and convergent and discriminant validity were addressed. Two hundred one undergraduates completed self-report measures of positive automatic thoughts, negative automatic thoughts, depressive symptoms, anxiety symptoms, and positive affectivity. The ATQ-P and ATQ-RP both showed high internal consistency, strong negative associations with depressive symptoms, specificity to depressive symptoms rather than anxiety symptoms, an average state-of-mind (SOM) ratio in the positive dialogue range, and a stronger relation with each other than with a measure of positive affectivity. The only notable difference between the measures was a significantly lower mean score (correcting for number of items) on the ATQ-RP. This paper is based on a thesis completed by the first author, under the supervision of the second author, in partial fulfillment of the requirements for the Master of Arts degree at American University. We are grateful to thesis committee members Lorah Dorn and Jim Gray for feedback on this material.  相似文献   
52.
We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease.  相似文献   
53.
An efficient BASIC program was established on Apple-Ⅱmicrocomputer with the CHESTAC-35F pulmonary function testing system tocalculate the time-constant histogram from the spirogram.By a set of analogousstudies,we confirmed that the recovered time-constant histogram was within onecompartment of the assumed one and that the root of mean square values of theresiduals between the experimental and model volume-time curves was 0.02.Infour healthy adult subjects,the mean value of time-constant histograms(TCx)hadthe variation coefficient 6.6%.The results show that our method is reliable andreproducible,and it can be used for clinical investigation.  相似文献   
54.
R波相关振动法血压测量   总被引:1,自引:0,他引:1  
为了提高振地血压测量的准确性,提出了一咱基于心电R波与血压振动波之间相关性,识别振动信号的一种抗干扰方法=-R波相关法,结合振动波形特征识别,该方法可有效地提取信号,消除干扰影响,该算法已在16位8098单片机上实现,本文同时给出了程序的详细流程图。  相似文献   
55.
This paper reflects on a research project funded by a consortium of leading sheltered housing (SH) providers and their regulatory body, the Housing Corporation. The project aimed to ascertain which aspects of SH older people perceived to be central to their satisfaction and the methods they judged most appropriate to measuring this. We outline key policy developments of importance to SH (specifically the development of performance measurement regimes), and changes in the nature of SH, which are driving providers to re‐evaluate how they measure user satisfaction. We discuss the aims of the project, our methodology and findings, and conclude by raising critical questions about the process of measuring satisfaction within an increasingly managerialised housing system. We argue that this favours standardised methods of information gathering (such as questionnaires) rather than engage with clients in order to develop methods and systems capable of eliciting qualitative issues of concern to them. Our conclusions are, we believe, applicable to health and social care provision, where similar tensions exist around performance measurement and user satisfaction.  相似文献   
56.
正常成人脑外段视神经的MRI研究   总被引:2,自引:2,他引:0  
目的 评价正常成人视神经-眼平面(NOP)视交叉以外段颅神经的MRI表现,建立正常标准。方法 随机选择正常成人志愿者50例,采用GB1.5T MR/i echo spood plus超导型磁共振成像仪及相控阵头线圈,成像序列包括自旋回波T1加权成像(SET1WI)和自旋回波T2加权成像(SET2WI);扫描方位以NOP平面为基准扫描。分别测量两组视神经眼球后神经膨大段直径、眶内段视神经直径、长度,管内段视神经直径及该段视神经起始至同侧视交叉的长度,后者与眶内段视神经长度之和即代表颅外段视神经的长度。结果 NOP平面上,正常人眼球后神经膨大段直径为4.2±0.56mm,眶内段直径为3.1±0.45mm、长度为24.6±2.88mm,管内段视神经直径为3.2±0.49mm,至同侧视交叉的长度为18.7±2.40mm,颅外段视神经的长度为43.3±3.83mm。统计分析,正常成人组内性别和年龄、双侧视神经之间无显著差异。 结论 NOP平面评价视神经有很大优势,MRI可以很好显示视神经的形态,是研究其解剖和疾病的有效检查手段。  相似文献   
57.
BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary.  相似文献   
58.
Summary Using xenon-enhanced computed tomography for the study of cerebral blood flow, simultaneous measurements of end-tidal and arterial blood xenon concentrations using the blood collection method were performed to investigate the validity of substituting the end-tidal for the arterial blood xenon concentration. Simultaneous measurement by both methods was performed 68 times in 27 patients. There was no statistical correlation between the arterial blood accumulation rate constant obtained by arterial blood and end-tidal samples, nor between the arterial blood saturation value obtained by the two methods, even when correction was made for age. In brain tissue, all parameters calculated using the end-tidal concentration were lower than those using arterial blood. We therefore suggest that cerebral blood flow values calculated using end-tidal xenon concentration are useful only for qualitative cerebral blood flow mapping, and not applicable to absolute values of cerebral blood flow.  相似文献   
59.
经对292例正常胎儿枕额径和双顶径的外测量,结果表明,枕额径和双顶径都随着胎龄的增长而增大,但其生长速度则随着胎龄的增长而逐渐减慢。经回归分析原理,分别得出预测方程。枕额径增长的速度和双顶径增长的速度没有明显差异(P>0.05)。  相似文献   
60.
The time to loss of the adductor pollicis muscle response to ulnar nerve stimulation at 1 Hz (twitch) after succinylcholine, 1.5 mg.kg-1 intravenously (IV), or vecuronium, 0.1 mg.kg-1 (IV), administration was assessed visually in 134 children, age 2-13 yr, during clinically determined, deep halothane, enflurane and isoflurane anaesthesia. The overall time to twitch ablation and duration of succinylcholine's action is in agreement with published times obtained under controlled experimental conditions; the onset time following vecuronium is comparable to those observed during a similar anaesthetic background measured under controlled experimental conditions. Twitch ablation after succinylcholine was achieved in half the time needed following vecuronium regardless of anaesthetic agent. Succinylcholine's and vecuronium's onset time as well as succinylcholine's duration is adequately assessed by the outlined, simple clinical means. The choice of inhalation agent does not affect the time to visible twitch ablation in a clinically relevant manner; nor does it make an appreciable difference, in clinical terms, in succinylcholine's duration of action.  相似文献   
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