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101.
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
102.
103.
Yifat Cohen Anthony Spirito Cheryl Sterling Deidre Donaldson Ronald Seifer Barry Plummer Ruscinda Avila Kathy Ferrer 《Journal of child psychology and psychiatry, and allied disciplines》1996,37(8):989-993
Adolescents who were psychiatrically hospitalized ( N = 105) were classified as sexually abused, physically abused, both sexually and physically abused, or not abused, and studied to determine the prevalence of suicidal behavior and psychiatric disorders. Self-reports of hopelessness, depression, coping, and self-concept were also examined. No difference in suicidal behavior or psychiatric disorder, based on abuse history, was found, with one exception. Adolescents who were sexually abused, particularly those who experienced the most severe sexual abuse, used negative coping strategies more often than those not sexually abused. Findings suggest that symptomatology of adolescents who are psychiatrically hospitalized does not differ markedly based on history of abuse. 相似文献
104.
Ellert R. S. Nijenhuis Philip Spinhoven Richard van Dyck Onno van der Hart Johan Vanderlinden 《Journal of traumatic stress》1998,11(4):711-730
In this study, the prevalence and severity of traumatic experiences as reported by patients with dissociative disorders and with other DSM-IV psychiatric diagnoses were compared. Furthermore, the predictive value of emotional, physical, and sexual trauma with respect to somatoform and psychological dissociation was analyzed. In contrast with comparison patients, dissociative disorder patients reported severe and multifaceted traumatization. Physical and sexual trauma predicted somatoform dissociation, sexual trauma predicted psychological dissociation as well. According to the memories of the dissociative disorder patients, this abuse occurred in an emotionally neglectful and abusive social context. Pathological dissociation was best predicted by early onset of reported intense, chronic and multiple traumatization. Methodological limitations restricting causal inferences between reported trauma and dissociation are discussed. 相似文献
105.
The purpose of this study was to assess, in subjects with low back pain, the changes and their permanence in muscular performance after a 3 month progressive physical exercise program. Ninety subjects with chronic low back pain participated in the study. The study design was controlled and it was carried out in three groups: intensive training, home exercise, and control group. Isometric and dynamic muscle strength of the trunk and lower limb were measured, at the beginning of the study and after the 3 months exercise program, and then during each of the follow-up sessions. The Oswestry Index and back pain intensity were also determined. Both exercise groups received benefit from the progressive exercise program. Their muscular performance improved and their back pain intensity decreased significantly. Among the home exercise group, the Oswestry Index also changed positively. The results demonstrate that the home exercise program could be as effective as the intensive training program in increasing muscle strength, as well as decreasing back pain and functional disability among low back pain patients with mild functional limitations. 相似文献
106.
S. N. Sarbadhikari 《Medical engineering & physics》1995,17(8):579-582
The use of an artificial neural network (ANN) system to differentiate the EEG power density spectra in depressed from normal rats was tried. The beneficial effects of chronic physical exercise in reducing the effects of stress and therefore depression was also to be tested in animals by the same method. In this study, rats were divided into 4 groups, subjected to (i) chronic stress (D group); (ii) chronic exercise by treadmill running (EO group); (iii) exercise with stress (ES group) and (iv) handling (C group). The prefrontal cortical EEG, EMG and EOG were recorded simultaneously on paper and the digitized EEG signals were also stored in the hard-disk of a PC-AT through an ADC. After filtering the digitize signals, the EEG power spectra were calculated by an FFT routine. Three successive 4 s artefact-free epochs were averaged. The REM and NREM sleep periods as well as the awake period signals were analyzed separately. The FFT values from each of the 3 states, in the 4 groups of animals were tested by an ANN with 30 first layer neurons and a 2nd layer of a majority-vote-taker. The ANN could distinguish the depressed from the normal rats' EEG very well in REM (99%) sleep, NREM (95%) sleep and awake (81%) states. In most of the cases it identified the exercised rats' EEG as normal. 相似文献
107.
The physical attractiveness of 25 pairs of monozygotic (MZ) twins was rated independently for twins A and B. The MZ twins were rated alike in their physical attractiveness (r=0.54; corrected for attenuation,r=0.94). Physical attractiveness was uncorrelated with verbal intelligence but was associated, controlling statistically for the sex difference in attractiveness favoring females, with three of the eight traits in the Comrey inventory: Conformity, Extraversion, and Emotional Stability. In both sexes, greater emotional stability was associated with attractiveness; in males greater extraversion; and in females, greater conformity. When these twin correlations were adjusted for this association with attractiveness, the mean change in the value ofr was only 0.03, indicating that physical attractiveness does not appear to bias conclusions from twin studies. 相似文献
108.
Albertini-Yagi CS Oliveira RC Vieira JE Negri EM de Oliveira LR Saldiva PH Lorenzi-Filho G 《Respiratory physiology & neurobiology》2005,145(1):101-110
The study objectives were to compare in vitro transportability and physical properties of respiratory mucus, obtained invasively by direct collection (DC) right after endotracheal intubation and non-invasively by sputum induction with 3% hypertonic saline solution inhalation (SI) 24 h before the anesthesia. Twenty-two patients with no pulmonary disease scheduled for elective abdominal surgical procedures were studied. The parameters analyzed and the main results are as follows. (1) Transportability by cilia (MCT), SI was higher than DC (0.94+/-0.25 and 0.62+/-0.25; P<0.001). There was a significant correlation between the two methods and DC could be estimated by: DC=0.21+(0.44 SI) (r=0.44; P<0.001). (2) Transportability by cough (CC), SI was higher than DC (68.23+/-32.1 and 33.58+/-19.04 mm; P=0.002). (3) Contact angle (CA), SI was lower than DC (10+/-3 degrees and 22+/-14 degrees ; P=0.025). (4) Rheological properties (no significant difference obtained between SI and DC). These results indicated that SI changes mucus physical properties and transportability in non-expectorators. 相似文献
109.
Fein AJ Plotnikoff RC Wild TC Spence JC 《International journal of behavioral medicine》2004,11(3):135-142
The examination of physical environments to explain and promote physical activity is an important yet under-investigated area
of research inquiry. This study explored relationships between the perceived availability of physical environmental resources
and the perceived importance of these resources in relation to physical activity levels amongst youth. A self-report questionnaire
was completed by 610 students (mean age = 15.5 years old; 62% female participants) from four high schools (grades 9-12) in
rural Alberta, Canada. Perceived physical environment constructs explained 5% of the variance in physical activity, with home,
neighborhood, and school as significant domains. Perceived importance constructs explained 8% of the variance in physical
activity with school context showing the only significant relationship with physical activity. A hierarchical regression analysis
entered sex, grade, self-efficacy, peer, family and physical education teacher relationships, as the first block and eight
environmental constructs as the second block. The first block variables accounted for 22% of the variance and environmental
constructs accounted for an added 4% of the variance in physical activity. Perceived importance of the school environment
was the only environment variable significantly associated with physical activity (β = .14; p < .05) after taking into account
the impact of these traditional predictors. These findings reinforce the need to provide and support school physical environments
related to physical activity. 相似文献
110.
Bruce F. Pennington Shelley D. Smith Lon R. Cardon Javier Gayán Valerie S. Knopik Richard K. Olson John C. DeFries 《American journal of medical genetics. Part A》2002,114(3):260-268
Comorbidity is pervasive among both adult and child psychiatric disorders; however, the etiological mechanisms underlying the majority of comorbidities are unknown. This study used genetic linkage analysis to assess the etiology of comorbidity between reading disability (RD) and attention‐deficit hyperactivity disorder (ADHD), two common childhood disorders that frequently co‐occur. Sibling pairs (N = 85) were ascertained initially because at least one individual in each pair exhibited a history of reading difficulties. Univariate linkage analyses in sibling pairs selected for ADHD from within this RD‐ascertained sample suggested that a quantitative trait locus (QTL) on chromosome 6p is a susceptibility locus for ADHD. Because this QTL is in the same region as a well‐replicated QTL for reading disability, subsequent bivariate analyses were conducted to test if this QTL contributed to comorbidity between the two disorders. Analyses of data from sib pairs selected for reading deficits revealed suggestive bivariate linkage for ADHD and three measures of reading difficulty, indicating that comorbidity between RD and ADHD may be due at least in part to pleiotropic effects of a QTL on chromosome 6p. © 2002 Wiley‐Liss, Inc. 相似文献