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41.
The organization of motor responses in the orbicularis oris muscle following the delivery of punctate mechanical inputs to vermilion skin of the lips was studied in a group of young infants, school-age children, and adults during periods of voluntary lip muscle activation. A specially designed multi-point array skin contactor, coupled to a position-servo controlled linear motor, was highly effective in driving the early component of the perioral reflex (R1). Overall, the evoked R1 response obtained from the infant was of variable amplitude relative to the children and adults, lacked response specificity, and occurred it a longer latency. This brainstem mediated sensorimotor action appears to take on several characteristics of the adult form by the age of 12. The emergence and maturation of mechanically evoked perioral reflexes is discussed in relation to the acquisition of motor skills, including speech and smiling.  相似文献   
42.
Study Objective . To determine albuterol delivery by metered-dose inhaler (MDI) in an in vitro pediatric mechanical ventilatory circuit model. The influence of a spacing device, endotracheal tube (ETT) diameter and length, and air humidity was also investigated. Design . An albuterol MDI canister was connected to an AeroVent spacer or Airlife MDI adapter and ETT 4.0, 5.0, or 6.0 mm at commercially available and equal lengths. The ETT tip was attached to an in-line filter holder with a 1-μm type A/E glass fiber filter. Ventilator settings were fractional concentration of inspired oxygen 50%, tidal volume 250 ml, inspiratory:expiratory (I:E) ratio 1:3, rate 25 breaths/minute, temperature 35°C, and a decelerating flow pattern. Ten albuterol canisters were activated two times each (total 2000 μg) into dry (4.0-, 5.0-, and 6.0-mm ETT) and humidified air (4.0- and 6.0-mm ETT) and repeated in triplicate. Percentage MDI output was determined by weighing the filter before and after drug administration (balance sensitivity 10 μg). Significant differences (p≤0.05) among the groups with and without a spacer and in dry and humidified air were determined by ANOVA with Scheffe's multiple comparison test. Multiple regression was used to determine significant associations between ETT diameter and length and delivery. Main Results . With the AeroVent spacer in humidified air, delivery with the 4.0- and 6.0-mm ETT was approximately 2.3% and 5%, respectively. The spacer and dry air significantly improved delivery. Conclusions . In humidified air, the dose of albuterol by MDI with an AeroVent spacer should be doubled for children intubated with 6.0-mm ETT, and four puffs administered for every one puff desired for 4.0-mm ETT. The results of this investigation should prove useful in initial clinical trials of albuterol MDI in ventilator-dependent infants and children.  相似文献   
43.
A case report is presented in which a patient's initial complaint is of blurred vision after exercise (Uhthoffs symptom). Visual acuity and colour vision were found to be reduced after exercise. Additional neurological signs included homonymous scotomata and delayed visual evoked and somatosensory responses. Magnetic resonance imaging demonstrated multiple abnormal lesions in the brain. The significance of this symptom and its relationship to multiple sclerosis are discussed.  相似文献   
44.
OBJECTIVE: To examine the extent of weight gain in the first year of treatment in an early psychosis program. METHOD: Subjects were 114 individuals who had experienced a first episode of psychosis and had completed 1 year in a comprehensive first-episode program. Weight and body mass index were calculated on entry to the program and at 6 and 12 months. Most of the subjects were all being prescribed second-generation antipsychotics. RESULTS: Significant increases in mean weight were observed in these young individuals over the course of the first year of treatment. CONCLUSIONS: If we are to work toward optimum treatment for first-episode subjects then potential weight gain needs to be addressed at the beginning of treatment and monitored during treatment.  相似文献   
45.
The medical records of 124 children notified from Ravensmead Clinic, Parow, as having tuberculosis during 1987 were reviewed in order to determine the strength of the evidence on which the diagnosis was made. Arranging the diagnostic criteria in an hierarchical manner, as suggested by the World Health Organisation, the cases were categorised as suspect, probable or confirmed. Twenty-five were suspect cases (20%), 89 probable cases (72%) and the remaining 10 confirmed cases (8%). These findings indicated that notifications from the clinic were being made in accordance with internationally accepted practice. The use of the WHO approach for the categorisation of childhood tuberculosis cases is recommended for both clinical and epidemiological purposes.  相似文献   
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Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education.  相似文献   
48.
Severe hypokalemia in thyrotoxic periodic paralysis   总被引:1,自引:0,他引:1  
Thyrotoxic hypokalemic periodic paralysis is an uncommon but sometimes fatal disease in which early recognition and therapy may prevent untoward complications. The case of a 26-year-old Chinese man who presented to the emergency department with rapidly progressive profound weakness and severe hypokalemia (serum potassium, 1.2 mEq/L) is presented. The patient required endotracheal intubation, ventilatory assistance, and intravenous potassium administration. Emergency medical evaluation and management of this entity are discussed.  相似文献   
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