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121.
A female child with Weaver syndrome is described. She did not show the excessive growth characteristic of this syndrome until after adequate caloric intake was achieved by feeding through a gastric feeding tube. Her inadequate nutrition was a result of feeding difficulties during infancy. In addition, she had recurrent pulmonary infections, apneic spells, and severe developmental delay. She died at 16 months of sepsis, congestive heart failure, and respiratory arrest. The autopsy revealed marked atrophy of the brain and cardiac ventricular hypertrophy. Most of the brain changes were thought to be from hypoxia.  相似文献   
122.
Attitudes of teenagers toward sun exposure and sunscreen use.   总被引:6,自引:0,他引:6  
A survey of 220 adolescents attending a multiphysician pediatric office in Virginia was conducted to determine the frequency with which they used sunscreens. Eighty-one percent of the teenagers in the study stated that they spent most weekends in the sun; however, only 9% always used sunscreen, while 33% never did. Factors found to be associated with increased sunscreen use included female sex (odds ratio = 4.5, P less than .0001), having a best friend who routinely used sunscreen (odds ratio = 3.0, P less than .001), having parents who insisted on sunscreen use when the teenagers were children (odds ratio = 3.0, P = .006), and knowing that the maximum time for safe exposure to the sun is short (odds ratio = 6.2, P less than .0001). Adolescents with a history of skin cancer in the family were not more likely to use sunscreens than other teenagers. Thirty-three percent of the girls and 16% of the boys older than 15 years of age reported that they had visited a tanning salon at least once. This survey substantiates poor compliance with sunscreen use by teenagers despite increasing evidence of the dangers of excessive sun exposure.  相似文献   
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Suttle CM  Banks MS  Candy TR 《Vision research》2000,40(26):3665-3675
The visual evoked potential is commonly used to estimate visual acuity in infants. The stimulus used is temporally modulated in order to drive the cortical response. Here it is proposed that distortion products generated by a front-end nonlinearity may contaminate the acuity estimate. Specifically, the nonlinearity might convert temporal modulation of a high spatial frequency grating into apparent whole-field flicker. Thus, the VEP may reflect an artifactual response to a high spatial frequency that is not resolved at the cortical level. If this were the case, one could null or attenuate the flicker response by adding whole-field flicker to the grating stimulus. We looked for such nulling effects in 18 infants aged 6-17 weeks. No consistent evidence was found for the nulling effect, so it was concluded that infant VEP acuity estimates are not significantly contaminated by the hypothesized distortion product.  相似文献   
125.
BACKGROUND AND PURPOSE: Despite a 10% to 15% failure rate, endopyelotomy remains the treatment of choice for most patients with ureteropelvic junction (UPJ) obstruction. We present a novel technique of percutaneous endopyeloplasty, wherein a precise, full-thickness approximation of a standard longitudinal endopyelotomy incision is performed in a horizontal Heineke-Mikulicz fashion through the conventional solitary percutaneous tract via a nephroscope. We assess the feasibility and efficacy of percutaneous endopyeloplasty in a chronic porcine bilateral UPJ obstruction model and compare outcome data with those#10; of conventional endopyelotomy and laparoscopic pyeloplasty. MATERIALS AND METHODS: Partial UPJ obstruction was created in 20 kidneys (11 pigs) by laparoscopic ligation of the upper ureter over a 5F ureteral catheter. After development of hydronephrosis over a period of 4 to 6 weeks, percutaneous endopyeloplasty (N = 10), conventional percutaneous endopyelotomy (N = 5), or laparoscopic pyeloplasty (N = 5) was performed. The essential steps of percutaneous endopyeloplasty include retrograde ureteral catheterization, standard percutaneous endopyelotomy incision, mobilization of the distal ureteral lip, horizontal suturing of the endopyelotomy incision through the nephroscope, and nephrostomy drainage and ureteral stenting. Suturing was performed using a modified 5-mm laparoscopic device (Sew Right 5 SR; LSI Solutions, Rochester, NY), which was passed through the nephroscope. RESULTS: Percutaneous endopyeloplasty was technically successful in all 10 kidneys with a mean total operative time of 81.4 minutes (range 51-117 minutes). The mean endopyeloplasty suturing time was 29.4 minutes (range 20-64 minutes). Three kidneys required two sutures, while seven kidneys required three sutures to complete the endopyeloplasty. The solitary complication was a lower-pole infundibular stenosis. Over a mean follow-up of 7.7 weeks, all renal units showed relief of obstruction, as evidenced by regression of hydronephrosis,#10; improvement in T(1/2) and glomerular filtration rate on renogram, and a low intrapelvic pressure on Whitaker test. At autopsy, the endopyeloplasty site showed a fine, well-healed transverse scar with no evidence of residual suture on the mucosal surface. The mean caliber of the UPJ following endopyeloplasty (13.8F +/- 2.2F) was significantly greater (P = 0.01) than that following endopyelotomy (7.5F +/- 1.9F). Intraoperative extravasation on completion of endopyeloplasty was absent (N = 6) or mild (N = 4) compared with that seen in all five kidneys following endopyelotomy. CONCLUSION: Percutaneous endopyeloplasty is feasible, simple, reproducible, and effective. Its advantages over conventional endopyelotomy include transrenal performance of a Fenger-plasty, wider caliber of the UPJ, absence of extravasation, and shorter duration of ureteral stenting.  相似文献   
126.
Suttle CM  Banks MS  Graf EW 《Vision research》2002,42(26):2879-2891
Young infants can distinguish red from green without brightness cues which shows that neural pathways processing color information (the 'red-green' color-opponent pathway) are functional early in life. There is some doubt over whether the 'blue-yellow' pathway is functional in young infants. Here, we show that infants behave like tritanopic adults until 2-3 months post-term age. By 3-4 months, infants distinguish tritan stimuli, and therefore, the 'blue-yellow' pathway must be functional by that age. Our sweep visual evoked potentials to identical stimuli, however, are not significantly above noise levels, in disagreement with the behavioral responses. We discuss several possible explanations for the discrepancy.  相似文献   
127.
Body packing or internal concealment used by drug dealers to smuggle illicit substances, puts the body packer at risk of both imprisonment and death. We report our experience over a 4 year period from January 1996 to December 1999 of suspects presenting to our hospital (the largest series in Europe). A total of 572 cases were assessed radiographically and 180 were shown to be carrying foreign bodies. The commonest reasons for admission were suspected overdose or gastrointestinal obstruction. Thirty-six cases were admitted, of whom 7 required surgical intervention. No deaths occurred. Of all people detained for smuggling by internal concealment into Britain during this period, 27% were seen in our hospital. These cases may present alone or escorted by Her Majesty's Customs and Excise personnel, and one must be aware of this possibility even when situated away from a port of entry.  相似文献   
128.
Gas embolism is a known complication of minimal access procedures in which carbon dioxide insufflation is used. We report a case of significant venous and right heart gas embolization, which occurred during performance of routine minimally invasive vein harvesting. This was manifest by hemodynamic deterioration secondary to transmission by a patent foramen ovale into the left heart and coronary circulation. Techniques to predict, diagnose, and prevent this rare but potentially fatal complication of minimally invasive vein harvesting are suggested.  相似文献   
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130.
The aim of this study was to identify predictors of the use of health and human services by community residing persons with dementia and their family caregivers. Telephone interviews were conducted with a sample of 608 primary caregivers of community residing persons with dementia who were randomly selected from a state-wide dementia registry. The Anderson Behavioral Model of Health Care Use was used as the analytic framework. Hierarchical ordinary least squares regression models were developed to analyze predictors of health and human services use. Predisposing, enabling, and need variables explained 40.9% of the variance in service use, 29.8% of the variance in health service use, and 38.1% of the variance in the use of human services. Enabling variables explained more variance in the use of health and human services than did need or predisposing variables. In contrast to the health services utilization literature that points to the importance of need variables, the results of this study lend support to findings in the caregiving literature that indicate that enabling variables are at least as important as need variables in predicting the use of community services by family caregivers of persons with dementia.  相似文献   
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