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991.
R C Hunt  D M Bryan  V S Brinkley  T W Whitley  N H Benson 《JAMA》1991,265(15):1982-1984
This study assessed the capabilities of a traditional and an amplified stethoscope used by flight nurses to assess breath sound during air medical transport in an MBB BO-105 helicopter. We developed a normal breath sound model using a prerecorded tape of breath sounds interspersed with segments without breath sounds; the recorder had been placed in the chest wall of a resuscitation training manikin. Flight nurses completed control listening sessions in a quiet environment and experimental sessions during flight using a traditional stethoscope for half of the sessions and an amplified stethoscope for the remaining half. In the quiet environment, flight nurses accurately reported the presence or absence of breath sounds in 110 (92%) of 120 trials. During helicopter flight, none of the flight nurses heard breath sounds during any of the recorded segments with either the traditional stethoscope or the amplified stethoscope. We conclude that flight nurses are unable to hear normal breath sounds using a traditional or amplified stethoscope during flight in a medically configured MBB BO-105 helicopter. Improved stethoscopes, innovative methods of listening, and reduction of aircraft noise are potential solutions to the problems of breath sound assessment during air medical transport.  相似文献   
992.
993.
The paper reviews existing reports on relations between pathologies leading to malabsorption and dental lesion in children. The following dental alterations are reported in the literature: delayed eruption of deciduous teeth, hypoplasia of enamel and dental caries. These lesions have been observed in gastrointestinal pathologies, for example, coeliac disease, chronic diarrhea and recurrent vomiting, intolerance of cow's milk protein, Crohn's disease and salmonellosis. The delayed eruption of deciduous teeth and hypoplasia of the enamel are certainly correlated to malabsorption and maldigestion, especially if these are protracted over time. Dental caries may be due to poor oral hygiene, poor diet and to the presence of modified calcification. Only a comparative study with a control group will enable the effective prevalence to be assessed.  相似文献   
994.
A structured discourse strategy, employing child echoic imitations and adult expansion, was used to teach 5 autistic children two-term semantic relations. The 5 male preschoolers in late Stage I of linguistic development were exposed systematically to two-term semantic relations in a structured dialogue with a clinician. A combined multiple baseline and AB(A) design was used to examine the relationship between the clinician expansions and the children's subsequent spontaneous imitations and spontaneous productions. The results showed that an increase in modeling and expansion was related to an increase in the children's initial spontaneous imitations of two-term relations. Further, following the increase in spontaneous imitations, spontaneous productions of the two-term relations increased and were maintained, whereas spontaneous imitations subsequently decreased.  相似文献   
995.
996.
Sixty children aged 5-13 years with moderately severe asthma took part in a double-blind, placebo-controlled trial of ketotifen. The design incorporated a 22 week study period, the addition of ketotifen or placebo to the current medication, and a controlled withdrawal of the regular therapy. Children receiving ketotifen showed significantly lower mean numbers of asthma attacks and less absence from school. The addition of ketotifen to existing treatment was associated with marginally significant changes in rates of day and night wheezing. In the second phase of study, additional therapy was withdrawn from both the ketotifen and placebo groups which resulted in a high (percentage) withdrawal. Children receiving ketotifen did not have a significantly lower failure rate than those given placebo.  相似文献   
997.
Nasal Cytogram is a simple, economical and reliable investigation. Although its utility was recognised as early s1927, it has not gained much popularity. Here an attempt is madeto assess the efficacy of nasal cytology in the light of histology, to diagnose various nasal conditions.127 cases of common rhinological problem were studied at Govt. Medical College, Nagpur. This investigation was found to be simple, reliable & economical.  相似文献   
998.
999.
1000.
Idiopathic retroperitoneal fibrosis. A retrospective analysis of 60 cases   总被引:5,自引:0,他引:5  
Sixty patients with idiopathic retroperitoneal fibrosis presenting between 1965 and 1984 are reviewed. Their mean age at presentation was 56 years and the male:female ratio was 3:1. The commonest presenting symptoms were flank and abdominal pain, weight loss, nausea and polyuria. Physical examination was usually normal, expect for the presence of hypertension. Anaemia and elevation of erythrocyte sedimentation rate were usually present. Proteinuria was found in less than a third of patients at presentation and significant bacteriuria was uncommon. The correct diagnosis was made or suspected in very few patients before referral. The cumulative actuarial survival rate was 86% at 1 year and 78% at 2 years. Seventeen patients died; they were significantly older and more uraemic at the time of referral than those who survived. A few patients did well with either corticosteroid therapy or ureterolysis alone. In the majority, both operation and steroid treatment were necessary. In bilateral obstruction with residual function in both kidneys, bilateral ureterolysis proved superior to unilateral operation (each followed by steroid therapy) in conserving renal function. Operation alone or steroid therapy alone should be considered in cases where steroids or surgery respectively present particular hazards. The less traumatic unilateral operation should be considered in poor risk patients and in those whose renal function is absent on one side. In many survivors, disease activity has persisted for many years. Life-long follow-up is recommended.  相似文献   
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