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991.
992.
A biofeedback training system has been developed for providing the cerebral palsied child with precise auditory and visual information regarding the spatial position of his head. The child actively practices correcting his head position by using feedback delivered through a mercury-switch device called a head position trainer. Twelve children have received clinical training and results are discussed in terms of feedback-sensitive, feedback-trained and feedback-learned, the results of treatment dictating the classification. It is concluded that the head position trainer is an effective sensory aid for the cerebral palsied child in the development of head control and position awareness. It is proposed that this system has excellent potential use as an adjunct to regular therapy programming in that it provides additional daily practice time and an objective method of recording the child's progress.  相似文献   
993.
The histopathology of dysbaric osteonecrosis and the influence of the number of exposures, compression rate, and obesity on the incidence and latency of the lesion were studied in 438 mice (2505 bones were examined). The animals were subjected to 75 psig air pressure for 2-6 hours (single or multiple exposures). Compression was rapid or stage. Decompression was safe. Osteonecrosis developed in the epiphysis of the tibia and/or femur in 34.1% of obese and in 5.8% of thin animals after a latent period of 2 to at least 12 months. It was concluded that: 1. dysbaric osteonecrosis appears to be independent of decompression sickness; 2. in obese mice the incidence is higher and the latent period shorter; 3. multiple exposures result in higher incidence and earlier lesions than single exposure; 4. the incidence is lower with stage than with rapid compression; 5. the pathogenesis of osteonecrosis may involve several factors (circulatory impairment by extravascular or intravascular bubbles, emboli, thrombi, vasoactive substances, gas-induced osmosis, autoimmunity) acting in concert or in sequence.  相似文献   
994.
The systematic study on the distribution of heparin in 12 tissues of eight mammalian species is reported. It is shown that heparin varies from 1 microgram/g of dry tissue in cat liver up to 1000 micrograms/g of dry tissue in bovine ileum. Heparin was present in relatively high amounts in lung, ileum and skin, of most of the species analysed. It was also observed that heparin was conspicuously present in high amounts in thymus and lymph nodes of all the species except for rabbits. Conversely, heparin was not detected in brains of all the species and also in none of the rabbit tissues. Based on this characteristic distribution the possible physiological role of heparin is discussed.  相似文献   
995.
996.

Background  

The nutritional status of the aging individual results from a complex interaction between personal and environmental factors. A disease influences and is influenced by the nutritional status and the functional capacity of the individual. We asses the relationship between nutritional status and indicators of functional capacity among recently hospitalized elderly in a general hospital.  相似文献   
997.
Treatment of chronic airflow obstruction with inhaled corticosteroids at an early stage has been shown to preserve the lung function. We tested the hypothesis that "fear of corticosteroids" may be an important reason for nonparticipation in the Detection, early Intervention and Monitoring programme on Chronic obstruction pulmonary disease (COPD) and Asthma ("DIMCA") project. One thousand seven hundred and forty nine adult subjects from 10 general practices were invited to participate in the several parts of the "DIMCA" programme. Refusers were questioned about the reason(s) for nonparticipation. Together the screening, monitoring and three drug interventions of the study showed on average 25-35% refusers. The most frequent reasons for nonparticipation were absence of pulmonary symptoms and lack of time. For those invited to take part in one of the three drug interventions, "dislike of medication" was the most important reason for nonparticipation (33, 45 and 67% of the refusers). "Fear of corticosteroids" specifically was the reason for nonparticipation in 8% of the refusers on the basis of "dislike of medication". We concluded that a specific fear of corticosteroids was not a major obstacle for early intervention with inhaled corticosteroids.  相似文献   
998.
Based on a session at the 1997 conference on Information Resources and Academic Medicine sponsored by the Association of American Medical Colleges, this article illustrates how the beliefs and concerns of academic medicine's diverse professional cultures affect the management of information technology. Two scenarios--one dealing with the standardization of desktop PCs, the other with publication of syllabi on an institutional intranet--form the basis of this exercise. Four prototypical members of a hypothetical medical center community--the chairman of surgery, a senior basic scientist, the chief information officer of an affiliated hospital, and the chief administrative officer--offer their perspectives on each scenario. Their statements illustrate many of the challenges of planning, deploying, and maintaining effective information technology in the "multicultural" environment of academic medical centers.  相似文献   
999.
OBJECTIVE: Shoulder rotator muscle imbalances can contribute to subacromial impingement. The forces and movement patterns of wheelchair locomotion may contribute to these imbalances. This study attempted to determine whether National Wheelchair Basketball Association players of differing classifications had significant differences (p < or = .05) in concentric isokinetic peak shoulder rotator torque and torque ratios, and wheelchair locomotion dependence. DESIGN: Fifty-seven (class 1 = 12, class 2 = 24, class 3 = 21) of 117 total tournament participants (class 1 = 25, class 2 = 49, class 3 = 43) served as the convenience sample of volunteers for the survey portion, and 33 of these subjects (class 1 = 11, class 2 = 12, class 3 = 10) also entered the isokinetic portion of this study. SETTING: National wheelchair basketball tournament. RESULTS: Class 1 and 2 players had greater wheelchair dependence than class 3 players (p < or = .05). Peak torque or torque ratios generally did not differ among player classifications or with other populations. Class 1 players had weaker nondominant shoulder external rotator torque production at 60 degrees/sec (p < or = .03) compared with other classes and at 180 degrees/sec compared with class 3 players (p = .02), suggesting an inability to develop the "attenuation of dominance" noted among other groups. Diminished torque-producing capacity at 60 degrees/sec related to greater wheelchair dependence among class 1 players (p = .034). CONCLUSIONS: Class 1 players failed to demonstrate the acquired shoulder external rotator torque symmetry evident among class 2 and 3 players (with specific weakness of the nondominant shoulder external rotators). This torque symmetry difference was related to their greater dependence on wheelchair locomotion.  相似文献   
1000.
Exposure to disinfection by-products (DBPs) of drinking water is multiroute and occurs in households serviced by municipal water treatment facilities that disinfect the water as a necessary step to halt the spread of waterborne infectious diseases. Biomarkers of the two most abundant groups of DBPs of chlorination, exhaled breath levels of trihalomethanes (THMs) and urinary levels of two haloacetic acids, were compared to exposure estimates calculated from in-home tap water concentrations and responses to a questionnaire related to water usage. Background THM breath concentrations were uniformly low. Strong relationships were identified between the THM breath concentrations collected after a shower and both the THM water concentration and the THM exposure from a shower, after adjusting for the postshower delay time in collecting the breath sample. Urinary haloacetic acid excretion rates were not correlated to water concentrations. Urinary trichloroacetic acid excretion rates were correlated with ingestion exposure, and that correlation was stronger in a subset of individuals who consumed beverages primarily within their home where the concentration measurements were made. No correlation was observed between an average 48-hr exposure estimate and the urinary dichloroacetic acid excretion rate, presumably because of its short biological half-life. Valid biomarkers were identified for DBP exposures, but the time between the exposure and sample collection should be considered to account for different metabolic rates among the DBPs. Further, using water concentration as an exposure estimate can introduce misclassification of exposure for DBPs whose primary route is ingestion due to the great variability in the amount of water ingested across a population.  相似文献   
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