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941.
942.
Stürze im Alter     
The consequences of falls can be considerable for elderly people. They often lead to fractures or other injuries, immobility, curtailed independence, need for long-term care, and even death. They decrease the quality of life and can exert a negative influence on self-esteem, activity level, and the number of social contacts. The annual rate of falls in people over 65 is approximately 30%. This number increases to about 50% up to the age of 80 years and almost half of those who fall do so more than once during the course of a year. More than 90% of all falls occur in everyday situations, mostly resulting from movement errors. All studies demonstrated a significant correlation between muscle weakness and the incidence of falls, thus representing a major risk factor for a fall. Gait disorders, hip fractures, and the loss of functional autonomy are closely related to falls and associated with age to a similar extent. Almost 90% of hip fractures in Germany are the result of a fall. From the individual and economic points of view, a fracture near the hip has serious consequences in old age. Based on research findings to date, vibration training could constitute an interesting alternative to classic methods of strength training in fall prevention programs. The aim of this contribution is to provide fundamental facts regarding epidemiology and prevention and to present a potential approach to implementing vibration training in multimodal programs designed to prevent falls.  相似文献   
943.
944.
945.
Social interactions between preschool behaviorally handicapped children were measured under three experimental conditions during free-play: (a) active teacher involvement in free-play, (b) no teacher involvement in free-play, and (c) teacher structured free-play. Significantly more child-child interactions occurred during teacher structured free-play than in either of the other two conditions, with the no teacher involvement condition producing significantly more child-child interactions when compared to the active teacher involvement condition. Additionally, significantly more teacher-child interactions occurred during the active teacher involvement condition than in either of the other two conditions, with nonsignificant differences in teacher-child interaction between the no teacher involvement and the teacher structured conditions. The results are discussed in terms of their implications for ameliorating social interaction deficits among young behaviorally handicapped children.  相似文献   
946.
WISC-Rs and Stanford-Binets were administered to 50 children with developmental disabilities referred for comprehensive evaluations. Although the two IQs correlated highly and significantly, it was found that 54% of the children received different classifications using the two instruments. Thus, testers should be aware that different classifications of intellectual level may be derived for the same child depending upon which test is used.  相似文献   
947.
948.
The effects of teacher-delivered social reinforcers on the task persistent behavior of children enrolled in an intermediate class for the educable mentally retarded were studied. These children were grouped with a regular fourth grade class during a social studies period in which the study was conducted. The special education children were randomly divided into two groups, with seven children in each group. Using a reversal design, social reinforcers were delivered contingent upon the task persistent behavior of the seven target children. The seven youngsters in the control, or nonreinforcement, group were essentially ignored as they engaged in appropriate task-related behaviors. The results clearly show that increases in the level of task persistent behavior and the administration of social reinforcement were functionally related. The level of task persistent behavior emitted by the control children was not affected by reinforcement delivered to their peers.  相似文献   
949.
BackgroundIndividuals with diabetes have greater central arterial stiffness, wave reflections, and hemodynamics, all of which promote the accelerated cardiovascular pathology seen in this population. Acute aerobic exercise has been shown to be an effective strategy for reducing central arterial stiffness, wave reflections, and hemodynamics in healthy individuals; however, the effects of acute aerobic exercise in reducing these outcomes is not well established in people with diabetes. Recently, implementation of high-intensity interval exercise (HIIE) has shown superior improvements in cardiovascular health outcomes when compared to traditional aerobic exercise. Yet, the effect of HIIE on the aforementioned outcomes in people with diabetes is not known. The purpose of this study was to (i) describe the central arterial stiffness, wave reflections, and hemodynamic responses to a bout of HIIE and moderate-intensity continuous exercise (MICE) in adults with diabetes; and (ii) compare the effects of HIIE and MICE on the aforementioned outcomes.MethodsA total of 24 adult men and women (aged 29–59 years old) with type 1 (n = 12) and type 2 (n = 12) diabetes participated in a randomized cross-over study. All participants completed the following protocols: (i) HIIE: cycling for 4 × 4 min at 85%–95% of heart rate peak (HRpeak), interspersed with 3 min of active recovery at 60%–70%HRpeak; (ii) MICE: 33 min of continuous cycling at 60%–70%HRpeak; and (iii) control (CON): lying quietly in a supine position for 30 min.ResultsA significant group × time effect was found for changes in central systolic blood pressure (F = 3.20, p = 0.01) with a transient reduction for the HIIE group but not for the MICE or CON groups. There was a significant group × time effect for changes in augmentation index at a heart rate of 75 beats/min (F = 2.32, p = 0.04) with a decrease following for HIIE and MICE but not for CON. For all other measures of central arterial stiffness and hemodynamics, no significant changes were observed (p > 0.05).ConclusionA bout of HIIE appears to lead to a greater transient reduction in central systolic blood pressure than the reduction observed following MICE; however, both HIIE and MICE improved augmentation index at a heart rate of 75 beats/min in people with diabetes. There was no significant difference in response to HIIE and MICE in all outcomes. This provides preliminary evidence on the role of HIIE on such outcomes in people with diabetes.  相似文献   
950.
The effects of group dependent and group interdependent reinforcement contingencies on the level of socially appropriate behaviors emitted by emotionally handicapped elementary school students were examined. The investigation employed an ABAC design with a systematic replication (ACAB) across a second classroom. The findings suggested that: (a) Both group dependent and group interdependent reinforcement contingencies were effective in incieasing the level of socially appropriate behaviors. (b) For Classroom II, group interdependent reinforcement contingencies more often resulted in higher rates of responding for individual subjects than did group dependent reinforcement contingencies. (c) Group interdependent contingencies were shown to set the occasion for cooperative behavior among class members designed to help each other achieve individual but interdependent goals.  相似文献   
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