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81.
82.
A versatile timer has been developed for use in psychological research which can be used to measure a subject's reaction times in response to sequences of visual or auditory stimuli. The timer is programmed by a twenty channel punched tape programmer and the subject's reaction times are displayed in digital form. The time units can be varied by decades over the range 1 msec-1 sec and each measured reaction time is continuously displayed until just before a new stimulus is presented. Two applications for which the unit can be used are (1) the determination of paced serial reaction time using a multiple choice visual display combined with visual and audio distractors and (2) a modification of the Stroop Colour-Word Test. Any error in response is indicated by the illumination of a red light mounted close to the digital display.  相似文献   
83.
This study compares a standard soft dressing (SSD) with a removable rigid dressing (RRD) in a randomized, controlled trial using 50 dysvascular trans-tibial amputees. Both dressing types were applied immediately post-operatively and were only removed for wound dressing changes. Half the subjects were allocated prospectively by ballot to either the RRD group or the SSD group. There was a strong trend indicating that primary wound healing of the stump occurred almost 2 weeks earlier in subjects using the RRD (RRD = 51.2 days +/- 19.4; SSD = 64.7 days +/- 29.5; P= 0.07; RRD: n =17; SSD: n = 14.) There were no significant differences between the other parameters measured which included time to prosthetic fitting, length of hospital stay, incidence of stump breakdown, and time taken for stump volume to stabilize. The incidence of stump damage due to falls was also recorded, the results indicating that RRDs may protect the new stump from trauma.  相似文献   
84.
PURPOSE: Depression is a risk factor for incident coronary heart disease (CHD), and predicts poor prognosis for patients post-myocardial infarction (MI). Few population-based, prospective studies have tested a gradient risk for depressive symptoms on CHD incidence. METHODS: The sample (n=1302) was derived from the Nova Scotia Health Survey-1995 (NSHS95), an age- and sex-stratified, random, population-based health survey. All subjects were 45 years or older, free of overt CHD at baseline, and completed the Center for Epidemiological Studies-Depression (CES-D) scale. Covariates included age, sex, body mass index, physical activity level, family history of premature CHD, diastolic blood pressure, lipids, smoking, alcohol use, diabetes, and education level. For the 4 years following NSHS95, MI-related hospitalizations (ICD-9-CM code 410) and CHD-related deaths (ICD-9-CM codes 410-414) were extracted from the provincial, universal healthcare registry. RESULTS: Fifty-two participants experienced a CHD event. A one standard-deviation increase in CES-D score was associated with a 1.32 hazard risk (confidence interval, 1.01-1.71) of CHD events, controlling for established CHD risk factors. CONCLUSIONS: An independent, gradient association between depression and incident CHD was detected in a population-based sample with complete 4-year CHD data. This evidence supports the value of investigating mechanisms linking depression and CHD.  相似文献   
85.
86.
A technical evaluation of the Exeter recording nappy has been carried out with particular reference to (a) linearity, (b) reproducibility of calibration, (c) the effect of variation in the position of moistened zones produced by consecutive leakages and (d) the effect of variation in the electrical conductivity of the liquid detected. The clinical use of the nappy is also discussed. A miniature alarm coupled to a similar pad arrangement has been developed as a training system for the geriatric incontinent patient and patients with neurogenic bladders. A 'pad and pant' version of an enuresis alarm has also been designed which had advantages over the conventional under-sheet type.  相似文献   
87.
88.
A number of recent studies have shown that beta-amyloid (Abeta) inhibits the induction of long-term potentiation (LTP) in the hippocampus. However, little is known about the mechanisms underlying such inhibition of LTP. In the present study, we present evidence that the cytokine tumor necrosis factor (TNF) alpha has a key role in the Abeta inhibition of LTP. The suppression of LTP by Abeta was absent in mutant mice null for TNF receptor type 1 (TNF-R1) and was prevented by the inhibitors of TNFalpha, infliximab and TNF peptide antagonist, and by the inhibitor of TNFalpha production, thalidomide. In addition, exogenous TNFalpha inhibited LTP induction, an action mediated via TNF-R1 as such inhibition was absent in mutant mice null for TNF-R1. The inhibition of LTP by TNFalpha involved activation of group I metabotropic glutamate receptor and p38 MAP kinase, identical to that for the Abeta-mediated inhibition of LTP induction.  相似文献   
89.
OBJECTIVE: To examine whether enteral feeding is a safe technique to use in the acute stage of spinal cord injury. METHODS: We searched the departmental computerised patient database and clinical records for all patients with spinal cord injuries admitted to the Auckland Hospital Intensive Care Unit (ICU), known as the Department of Critical Care Medicine (DCCM), between January 1988 and December 2000. Patients were included in the study if they had suffered complete spinal cord transection resulting in either paraplegia or quadriplegia. Data was collected for the following variables: length of time to commence enteral feeding, type of enteral feeding, duration of enteral feeding and reasons for interrupting the feed. RESULTS: Thirty-three patients were found and were included in the study. Twenty-seven (82%) of the patients commenced enteral feeding in the DCCM, 25 by nasogastric (NG) and 2 by nasojejunal (NJ) tube. Feeding was commenced a median of 2 days after admission and the median length of enteral feeding was 7.7 days. The main feeding complications that resulted in interrupting the feed were high gastric aspirates. One patient commenced on enteral feeding developed medical complications that prevented continuation. Two patients on NG feeding converted to NJ feeding. CONCLUSION: No major complications associated with enteral feeding were seen in this study. This would indicate that enteral feeding can be safely administered in the acute stage of spinal cord injury provided complications are monitored for daily.  相似文献   
90.
BACKGROUND: An important prognostic factor in neonatal brachial plexus palsy is the time interval to biceps muscle recovery. Although the natural history is not clear, biceps muscle recovery after more than three months of age has been used to predict poor long-term shoulder function. The absence of biceps muscle function at three months of age has been adopted as an indication for early brachial plexus microsurgery, in an attempt to improve recovery. To provide a benchmark for outcome comparison, the long-term outcome of patients with absent biceps muscle function at three months of age was studied. METHODS: Between 1980 and 1992, 170 patients with neonatal brachial plexus palsy were entered into a prospective study in which details of the birth and serial clinical examinations were recorded. Patients were grouped according to the level of injury and the time interval to biceps muscle recovery. Twenty-nine patients were observed to have absent biceps muscle function at three months of age. Twenty-eight of those patients were available for long-term followup at a mean age of eleven years and one month. At the time of follow-up, patients answered a questionnaire and underwent manual muscle strength testing, sensory evaluation, and grading of their shoulder function according to Gilbert's modification of the Mallet score, in which the function was graded as II, III, or IV with class I (no function) and V (normal) eliminated. The level of injury and the time that biceps muscle function returned were compared with the final outcomes. RESULTS: The level of injury was C5-C6 in thirteen (46%) of our twenty-eight patients with absent biceps muscle function at three months of age, C5-C7 in five (18%), and pan-plexus (C5-T1) in ten (36%). Biceps contraction was observed by six months of age in twenty patients (71%), including all thirteen patients with a C5-C6 level of injury. Twenty-two patients did not have surgery on the brachial plexus, but nine of those patients had subsequent orthopaedic procedures. At the time of follow-up, twenty-seven of the twenty-eight patients had at least antigravity biceps muscle function. Patients who regained biceps muscle function between three and six months of age had better scores for abduction (p = 0.04) and for hand-to-neck (p = 0.05) and hand-to-back (p < 0.001) function than did patients who regained biceps muscle function after six months of age. Patients with a C5-C6 lesion had better scores for external rotation (p = 0.04) and for hand-to-neck (p = 0.05), hand-to-mouth (p < 0.01), and hand-to-back (p < 0.001) function than did patients with a pan-plexus lesion. Twelve (55%) of the twenty-two patients who did not have brachial plexus surgery had a class-IV shoulder (good function) according to the modified Mallet score. Of the twelve patients with a C5-C6 level of injury who did not have brachial plexus surgery, eight had a class-IV shoulder. CONCLUSIONS: This study indicated associations between prolonged neurological recovery and a more extensive level of injury and worse long-term shoulder function. Patients with a C5-C6 injury and absent biceps muscle function at three months of age often have good long-term shoulder function without brachial plexus surgery.  相似文献   
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