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81.
82.
Aim: To evaluate whether the ventricular septal defect (VSD) size, along with the degree of preoperative growth impairment and age at repair, may influence postoperative growth, and if VSD size can be useful to identify children at risk for preoperative failure to thrive. Methods: Sixty‐eight children submitted to VSD repair in a Brazilian tertiary‐care institution were evaluated. Weight and height measurements were converted to Z‐scores. Ventricular septal defect size was normalized by dividing it by the aortic root diameter (VSD/Ao ratio). Results: Twenty‐six patients (38%) had significantly low weight‐for‐height, 10 patients (15%) had significantly low height‐for‐age and 13 patients (19%) had both conditions at repair. Catch‐up growth occurred in 82% of patients for weight‐for‐age, in 75% of patients for height‐for‐age and in 89% of patients for weight‐for‐height. Weight‐for‐height Z‐scores at surgery were significantly lower in patients who underwent repair before 9 months of age. The VSD/Ao ratio did not associate with any other data. On multivariate analysis, weight‐for‐age Z‐scores and age at surgery were independent predictors of long‐term weight and height respectively. Conclusion: The VSD/Ao ratio was not a good predictor of preoperative failure to thrive. Most patients had preoperative growth impairment and presented catch‐up growth after repair. Preoperative growth status and age at surgery influenced long‐term growth.  相似文献   
83.
84.
In a study using gas chromatography-mass spectrometry (GC-MS) on urine specimens from 16 normal infants and 16 infants with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (aged 1 day to 4 weeks), the major steroids recognized in all infants were: 16 alpha-hydroxy-dehydroepiandrosterone, 16 beta-hydroxy-dehydroepiandrosterone, 16-oxo-androstenediol, androstenetriol, 15 beta,17 alpha-dihydroxy-pregnenolone and 16 alpha-hydroxy-pregnenolone. Pregnanetriol was detectable in three normal infants (aged 3, 6 and 15 days) but the levels seen in 15 CAH patients were in a higher range. Pregnanetriolone, 5 beta-17-hydroxy-pregnanolone and 15 beta,17 alpha-dihydroxy-pregnanolone were present in the urine of 15 CAH patients, but were not detectable in any of the normal infants. The older the patient, the higher the level was of each of these four steroids. The results indicate that, even on day 1, patients with CAH due to 21-hydroxylase deficiency may be positively identified using GC-MS of urine specimens. This does not preclude the possibility that a minority of patients with CAH, most likely those with mild 21-hydroxylase deficiency, may not exhibit the characteristic GC-MS findings on day 1, as seen in one of the 16 CAH patients.  相似文献   
85.
The commonly held hypothesis that androgens cause testicular descent in the male [9] predicts that excess endogeous androgens in the female fetus might cause descent of the ovary. To re-evaluate this prediction from a clinical perspective, a retrospective review was made of genotypic females with congenital adrenal hyperplasia and severe virilization. Patients with maximal virilization were included, since this is the group with the earlies and highest production of adrenal androgens during fetal development. Records were reviewed of five children in whom the external genitalia were completely or almost completely masculinized, who had been regarded as males with undescended testes at birth. The position of the ovaries was determined where possible from operative or pathological reports. In four patients the ovaries had been identified at operation, and were found to be in their normal position. In none were the ovaries in or adjacent to the inguinal canal. In the most recent patient, who presented in 1979, laparotomy was not performed because of the belief that the female internal genitalia were normal. In addition, review of the literature revealed two other similar female children with maximal virilization but documented normal ovarian position. The significance of these well-known findings has been ignored in recent studies of testicular descent. Failure of endogenous androgens to affect ovarian position supports the view that initiation of gonadal descent is independent of androgens. Since Müllerian inhibiting substance is the other recognizable hormone in the fetal testis apart from testosterone, it is suggested that it may be responsible for initiating gonadal descent.  相似文献   
86.
A large-scale review of the literature concerning the effects of noise on hearing, published primarily during the 1970s, was initiated by the National Institute of Neurological and Communicative Disorders and Stroke in 1981. This review demonstrated a continuing search for medicinal treatment for the adverse effects of noise on hearing. The present article focuses on the results of investigations of human subjects. The literature in this area is primarily European and deals principally with treatment of acoustic trauma, although a few reports have described attempts to render the ear less susceptible to the hazards of chronic noise exposure. Much of the published information is of questionable value because of inadequate experimental design and control. To date, the search for effective medicinal treatment for hearing loss caused by noise has been unsuccessful. Results reported from studies of the effects of carbogen are encouraging and suggest that continued rigorous investigation of this agent is warranted.  相似文献   
87.
Laryngeal aerodynamics associated with selected voice disorders   总被引:1,自引:0,他引:1  
Measures of estimated subglottal air pressure and laryngeal air flow during speech production are compared for adults with normal laryngeal function and those with laryngeal abnormalities. The most traditional measure, air flow during sustained vowel production, is not a strong predictor of laryngeal function during speech production. Subglottal air pressure and laryngeal air flow offer insight into voice disorders and provide directions for therapy as well as a method for the quantitative assessment of treatment outcomes.  相似文献   
88.
89.
The effect of three chemicals with different mechanisms of action (3,4-dichloroaniline, fenoxycarb, and chlorpyrifos) on the life history response of the cladoceran Ceriodaphnia cf. dubia was examined under both limited (3 x 10(4) cells/mL) and abundant (15 x 10(4) cells/mL) food conditions. Toxicity tests were conducted at both food concentrations simultaneously for each chemical, and cladocerans were examined daily from less than 24 h old until their death. A range of life history parameters were calculated, including mean brood sizes, survival, net reproductive rate, and population growth rate. The toxicity of 3,4-dichloroaniline was not significantly affected by food concentration. However, limited food significantly decreased the toxicity of fenoxycarb, and significantly increased the toxicity of chlorpyrifos. The effect of food concentration on toxicity appears to depend on the mechanism by which the chemical exerts its toxicity and on food--chemical interactions. Possible mechanisms for the different effects of food concentration on toxicity are discussed.  相似文献   
90.
Objective : To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation F iO2 >80% (OR 3.4; 95% Cl 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury.  相似文献   
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