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71.
The frequency of reversible and irreversible visual impairment was determined in children with severe and profound sensorineural deafness, as subnormal vision can adversely affect their educational and social development. Eighty three of 87 such children attending an audiology service were examined to assess the incidence and severity of visual impairment. Each child underwent a detailed ophthalmic assessment. The criteria for visual impairment were visual acuity < 6/9 Snellen or equivalent and/or abnormal binocular vision. Forty five had a normal ophthalmic examination (54.2%). Twenty nine had visual impairment (34.9%) and nine had ophthalmological abnormalities that did not interfere with vision (10.9%). A higher proportion of children with risk factors for visual pathology demonstrated visual impairment than those in whom there were no risk factors. None the less, 44% of visual impairment was among patients without risk factors. The results underline the need to examine all children with severe and profound sensorineural deafness soon after diagnosis and indicate that children with multiple handicaps have a greater likelihood of visual impairment (11 of 14 cases).  相似文献   
72.
The objective of this study was to determine whether there was a relationship between levels of particulate matter with an aerodynamic diameter of less than 10 microns (PM10) and upper respiratory disease (URD) rates in soldiers deployed to Bosnia in 1997 and 1998. PM10 levels were divided into quartiles and upper and lower 50th percentiles. When all camps were combined, there was a statistically significant association between the PM10 maximum level and URD rates based on Kruskal-Wallis and Mann-Whitney U tests, and the Pearson correlation was statistically significant. Although the relationship was not statistically significant in analyses conducted of the individual camps, the average URD rate increased with each quartile of PM10 maximum exposure. There was no statistically significant association between PM10 average exposure and URD rates, although the average URD rate increased with each quartile of PM10 average exposure. Although these results are not conclusive, there appears to be a relationship between PM10 levels and URD rates in soldiers deployed to Bosnia in 1997 and 1998.  相似文献   
73.
Little explicit attention has been given to the potential impact of client challenging behavior on staff psychological well-being. Relevant research was critically reviewed according to criteria required to establish a causal relationship. Reasonable evidence was found for an association between challenging behavior and staff stress, and some evidence for temporal precedence. However, few researchers had analyzed data enabling alternative explanations to be eliminated. Thus, empirical evidence of a causal relationship between challenging behavior and staff stress is weak. A fourth causality criterion was addressed by suggestion of a mechanism by which challenging behavior may have its effects. I propose that staff negative emotional reactions mediate the impact of challenging behaviors on staff stress and evaluate research evidence for this theory.  相似文献   
74.
Self-efficacy has been identified in the general parenting literature as an important variable affecting parent outcomes. In the present study, 26 mothers and 20 fathers of children with autism reported on their self-efficacy, anxiety, and depression. Teachers rated the behavior problems of the children. Regression analyses showed that self-efficacy mediated the effect of child behavior problems on mothers' anxiety and depression, but there was no evidence that it functioned as a mediator for fathers. However, there was evidence that self-efficacy moderated the effect of child behavior problems on fathers' anxiety. No evidence for the moderating effect of self-efficacy was apparent for mothers. Methodological issues and the theoretical and practical implications of these results are discussed.  相似文献   
75.
76.
cAMP is a ubiquitous second messenger, which acts mainly through specific protein kinases that consist of two regulatory and two catalytic subunits. An unsolved problem in cAMP physiology is how it can regulate so many cellular functions through this simple enzymatic cascade. A tentative explanation is related to the different biochemical properties of the four regulatory subunit isoforms (RI alpha and RI beta, RII alpha and RII beta) and to their differential cell and tissue distribution. For example, detergent insoluble aggregates of RI alpha are present in some cholinergic neurons of the adult rat brain. Rat brains, from the embryonic stage to old age, were examined for the presence of highly concentrated clusters of RI alpha. They are present only in some neurons of restricted brain areas, for a limited time span. During development, labeled neurons appear in different brain areas after neuron migration, at a stage of advanced functional maturation. They have their greatest expression after birth but before sexual maturation, and then they slowly decline, persisting only in a few brain areas throughout life. The first appearance, time course, and eventual disappearance is different in the different brain areas: RI alpha clusters appear in brainstem, hypothalamus, and accessory olfactory bulb at a late embryonic stage; in the main olfactory bulb, hippocampus, and medial thalamic nuclei shortly after birth; and in the cortex as late as in the third and fourth postnatal week. During the rat's lifespan, the distribution of these peculiar RI alpha clusters undergo changes that may contribute to shape neuronal responses differentially to agents modifying cAMP levels.  相似文献   
77.
78.
Tardy posterolateral rotatory instability of the elbow due to cubitus varus   总被引:6,自引:0,他引:6  
BACKGROUND: Cubitus varus has long been considered merely a cosmetic deformity. The purpose of this paper is to demonstrate a causal relationship between cubitus varus and instability of the elbow. METHODS: In twenty-four patients (twenty-five limbs) with a cubitus varus deformity following a pediatric distal humeral fracture or resulting from a congenital anomaly (three limbs of two patients), tardy posterolateral rotatory instability of the elbow developed approximately two to three decades after the deformity occurred. All patients presented with lateral elbow pain and recurrent instability. The average varus deformity was 15 degrees (range, 0 degrees to 35 degrees ). Surgery was performed in twenty-one patients (twenty-two limbs). Treatment consisted of reconstruction of the lateral collateral ligament and osteotomy in seven limbs, ligament reconstruction alone in ten, osteotomy alone in four, and total elbow arthroplasty in one. RESULTS: In three patients, the triceps muscle was dynamically stimulated intraoperatively to contract while resisting extension of the elbow. This produced posterolateral rotatory subluxation of the elbow, which was reversed by corrective osteotomy and lateral transposition of a portion of the medial head of the triceps that originally had been attached to the elongated, deformed medial aspect of the olecranon. At an average of three years (minimum, one year) after the operation, the result was good or excellent for nineteen of the twenty-two limbs that had undergone an operation; three limbs had persistent instability. CONCLUSIONS: With cubitus varus, the mechanical axis, the olecranon, and the triceps line of pull are all displaced medially. The repetitive external rotation torque on the ulna permitted by these deformities can stretch the lateral collateral ligament complex and lead to posterolateral rotatory instability. Thus, cubitus varus deformity secondary to supracondylar malunion or congenital deformity of the distal part of the humerus may not always be a benign condition and may have important long-term clinical implications. Operative correction can relieve symptoms of instability. The indications for preventive corrective osteotomy remain to be determined.  相似文献   
79.
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.  相似文献   
80.
PURPOSE: Incidence data for severe aplastic anaemia (SAA) in children are scanty and vary. Few population based studies have been reported. A retrospective and prospective study was conducted to determine the incidence and course of SAA. PATIENTS AND METHODS: All children with a diagnosis of SAA in the Nordic countries from 1982 through 1993 were registered and have been followed up since 1987. RESULTS: A total of 101 children were diagnosed with SAA. The mean annual child population was 4.31 million. A constant incidence of 1.95/million children/year was found: 2.4 for boys and 1.5 for girls. A non-significant increase of cases occurred from November to March. Possible aetiological agents were noted in 29%. The actuarial survival was 79% after one year and 68% after five years without significant difference between boys and girls. CONCLUSION: The incidence of SAA in the Nordic countries remains stable with a preponderance among boys. SAA has still a high initial mortality and a risk of late deaths.  相似文献   
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