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41.
People undergoing medical procedures sometimes experience feelings that may influence the results. In this study, we explore the relationship between changes in mood state self-ratings and cerebral glucose metabolism during positron emission tomography (PET) in persons with age-associated memory impairment (mean age 59.4±9.8 years). Brain regions of interest involved in both mood and memory were examined. Mood ratings of increased boredom correlated significantly with mesial temporal and parietal asymmetry and decreased parietal metabolism. Mood ratings of increased fatigue correlated with basal ganglia asymmetry and the right basal ganglia and left mesial temporal metabolism. These findings suggest that subjective mood state changes during PET may influence metabolism in brain regions implicated in emotion and memory function in people with age-related memory complaints.  相似文献   
42.
The introduction of the variable-pitch feature on pulse oximeters in 1983 by the Nellcor Corporation (Hayward, CA) allowed users to rapidly detect changes in oxygen saturation by listening for changes in the pitch of the tones emitted by the pulse oximeter. A few individuals have reported that they have been unable to detect a change in pitch when oxygen saturation changes. To these individuals, the variable-pitch feature of these pulse oximeters has not been beneficial. Using the pitches from one manufacturer of oximeters, we created a computer program to simulate the pitches that accompanied various oxygen saturations. The pitches were recorded onto a tape player and played for 75 volunteer subjects unfamiliar with the pitches of a variable-pitch pulse oximeter. Of our sample, 67% were able to detect a single change in pitch corresponding to a 1% fall in oxygen saturation, and 11% of the population could not detect a change in pitch until there was a change in pitch with every beat. We suggested four alternative designs that may prove beneficial to this group of individuals.  相似文献   
43.
There is a great need today for clinically useful instruments in the rehabilitation of chronic pain patients. The Arthritis Self-efficacy Scale measures patients' perceived self-efficacy to cope with the consequences of chronic arthritis. The aim of the present study was to evaluate a Swedish version of the Arthritis Self-efficacy Scale with respect to factor structure and reliability. Twenty-five chronic pain patients and twenty-four rheumatology patients were given a Swedish version of the Arthritis Self-efficacy Scale twice within a three week interval. The three factor structure of the scale was confirmed; Cronbach's alpha for internal consistency ranged between 0.82-0.91 and test-retest correlations ranged between 0.81-0.91, showing that the instrument satisfactorily met psychometric standards.  相似文献   
44.
We have investigated the effect of growth and induction conditions on the production of soluble single-chain Fv antibody fragments in Escherichia coli under the control of wt lac promoter. The scFv was directed into the periplasmic space by a pelB leader sequence. Addition of sucrose to the medium gave a 15–25-fold increase in the yield of soluble scFv-phOx (3.0 mg/l) for bacterial shake-tube cultures and an increase of 80–150-fold (16.5 mg/l) for shake-flask cultures. Using flask culture in the presence of 0.4 M sucrose, a significant amount of scFv was released into the medium. We found that the scFv could be made to accumulate in the periplasm or be secreted into the medium by simply changing the incubation conditions and the concentration of the inducer. The ratio between soluble antibody fragments and insoluble scFv aggregates proved to be dependent on the strength of the promoter. Lowering the incubation temperature below 20°C had no effect on the yield of soluble antibody fragments in the periplasm, but they were no longer secreted into the medium. An example of high level production in shake-flask cultures and one-step purification by immobilized metal affinity chromatography (IMAC) is described for a soluble scFv specific for the T cell surface antigen CD3. The biological activity of the purified anti-CD3 scFv was demonstrated by flow cytometry. This method should be especially useful for the functional screening of a large number of clones in small-scale cultures.  相似文献   
45.
The aim of the study was to investigate if the stretch reflex of the soleus muscle was useful in quantifying upper motor neuron lesions. The soleus stretch reflex was recorded in 10 healthy subjects and 20 patients with active relapsing-remitting multiple sclerosis and correlated to the number of MRI lesions in cerebrum and clinical scores (expanded disability status scale and regional functional scoring system). The short latency stretch reflex was elicited by rotating the left ankle joint 4 degrees with a rise time in the interval of 40-640 ms. The amplitude of the stretch was larger in multiple sclerosis patients being 88.5 microV in patients and 12.8 microV in controls, P = 0.007. The sensitivity of the stretch reflex expressed as the slope of the best linear fit was increased in MS patients to 2.6 microVs/degree compared with 0.6 microVs/degree (0.1-2.2) in controls, P = 0.009. There was no correlation between amplitude of the stretch reflex and number of MRI lesions (r = -0.03). In conclusion, the soleus stretch reflex might be useful to quantify spasticity but is not useful in detecting dysfunction of upper motor neurons in MS.  相似文献   
46.
The ICD-10 and DSM-IV classifications have both given low priority to “reactivity” to acute stress as a classificatory principle for functional psychoses. In Scandinavia, reactivity is still considered an important factor in the development of such psychoses. Reactivity is a complex concept, and its various components are historically examined. The Reactivity of Psychosis Rating Form (RPRF) was developed in order to operationalize reactivity. Seven of the 10 elements of RPRF can be rated reliably. Factor analysis of the RPRF yields three factors: stressor, onset and change, that also show high interrater reliability. Our results indicate that RPRF has both construct and discriminant validity. Further studies with the RPRF may elucidate the true status of reactivity in functional psychoses.  相似文献   
47.
The effects of lung volume and respiratory airflow on airway resistance were studied in five anesthetized and paralyzed patients. Airway resistance measured during the inspiratory phase with intermittent constant airflow inflatoins decreased in inverse correlationship to increases in lung volume. Airway resistance measured during the expiratory phase with an airway interruption technique, on the other hand, increased with a linear relationship to the expiratory airflow as expressed by a function of Y = K1 + K2X. K1, calculated from the values of airway resistance corresponding to three different airflows, was unaffected by intentional expiratory resistance loading. Thus, simultaneously with the measurement of airway resistance by this method, expiratory gas sampling with a Douglas bag can be done if necessary. Since the K2 value of the endotracheal tube used in this study (Portex® I.D. 8mm, length 26cm) was quite high (5.0cmH2O·1–2·sec2), depending on the airflow, the presence of the endotracheal tube strongly affected the measurement of airway resistance during general anesthesia. K1 measured by the above method, however, may be considered as the best way to evaluate the lower airway resistance independent of either lung volume or expiratory airflow.(Sakai T, Yoshida H, Yano H et al.: Measurement of airway resistance in anesthetized and paralyzed subjects: proposal for evaluation of K1 values. J Anesth 2: 139–145, 1988)  相似文献   
48.
背景 全科医生是基层医疗服务的“主力军”,现有关于全科医生胜任力的研究大部分强调应着力提升全科医生的知识和技能水平,忽略了全科医生内隐素质的重要性。目前我国仍缺乏评估全科医生内隐胜任力的有效工具,开发全科医生内隐胜任力量表(GPICRS)对于提高基层医疗服务质量具有重要意义。目的 编制GPICRS,并对其进行评价,旨在为提升全科医生胜任力提供一定的参考。方法 在文献分析和行为事件访谈的基础上,形成初始版量表。于2021年9—12月,采用随机抽样法,从全国选取380例全科医生为研究对象,采用初始版GPICRS对其进行调查,通过项目净化、探索性因子分析、验证性因子分析、信效度分析验证量表的合理性,基于加权平均法评价全科医生的内隐胜任力水平,比较不同特征全科医生的GPICRS平均总得分及各维度得分。结果 共回收有效问卷335份(88.2%)。GPICRS由工作动机、自我效能感、医学人文关怀和医学职业素养4个维度14个条目构成。探索性因子分析结果显示,KMO值为0.737,Bartlett’s球形检验χ2=592.715、P<0.001,表明数据适合进行因子分析;按特征根>1.00...  相似文献   
49.
A 23-year-old primigravid patient who received epidural analgesia for pain of labour presented with persistent, apparently irremediable, unilateral analgesia. Computerized axial tomo-epidurography demonstrated absence of circumferential spread due to lateral placement of the catheter. Transforaminal escape of contrast medium into the paravertebral area had occurred and anterior and posterior midline partitioning of the epidural space was obvious. All the usual measures to promote contralateral analgesia, except re-insertion of the catheter, had been tried without success.  相似文献   
50.
脚压测量用传感器   总被引:1,自引:0,他引:1  
本文讨论了用于脚压测量的四类压力传感器,电阻式传感器、压电式传感器,光电式传感器,电容式传感器介绍了其结构、原理和特点,并分析了几种典型的测量接口电路。  相似文献   
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