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81.
The purpose of this study is to develop and test the reliability and validity of an Egyptian version of the Children's Health Locus of Control scale. A cross sectional study design was applied using a stratified random sample of 930 students from the final two grades of primary and all grades of the preparatory schools. A further convenience sample of 120 students was selected to examine test-retest reliability of the scale. A preliminary instrument was developed and consisted of 40 statements having one of two response forms; a Yes/No format and a 4-point Likert scale format From data analysis the later format showed higher validity and reliability than the former one. Construct validity of the scale is evidenced by the factor analysis which revealed five factors (Internal, Chance, Powerful Others, Fate and Self blame) consistent with the previous theoretical model of HLC. As indicated by eta coefficient the scale and the subscales showed strong discriminating power between subjects. The known group comparison indicated a good criterion validity of the scale and the subscales. The scale showed a considerable reliability as alpha coefficient was 0.73 with test-retest reliability of 0.65. Comparison of different groups of students indicated that the scale could be used with confidence for all age groups, though it was more reliable for the preparatory phase, for private and governmental schools for males and females and for different social strata. Further testing of the developed scale is indicated among Egyptian children in different cultures.  相似文献   
82.
83.
BACKGROUND: Although the recent decline in child mortality in Bangladesh is remarkable, death from causes other than infectious diseases and malnutrition remains an important component of child mortality. Death from drowning of children can be expected to be a problem in Bangladesh given the geographical features of the country. OBJECTIVE: The objectives of this study are to determine the trend, pattern, and correlates of drowning deaths. METHODS: Data are presented on deaths of children (1-4 years) due to drowning derived from a longitudinal, population-based surveillance system in operation in a rural area of Bangladesh in 1983-1995. Moreover, a case-control study was carried out to identify the risk factors associated with drowning. RESULTS: Deaths due to drowning ranged from about 10% to 25% of child deaths during 1983-1995. The absolute risk of dying from drowning remained almost the same over the study period but the proportion of drownings to all causes of death has increased. Drowning is especially prevalent in the second year of life. Age of the mother and parity have a significant impact on drowning. The risk of dying from drowning increases with the age of mother and much more sharply with the number of living children in the family. Two socioeconomic variables did not have an influence on the risk of drowning. CONCLUSIONS: A substantial proportion of child deaths could be averted if parents and other close relatives paid more attention to the safety of children. The Child Health Programme of the Ministry of Health and Family Welfare of Bangladesh should develop health education programmes for villagers alerting them to the dangers of drowning and measures to prevent it.  相似文献   
84.

Objectives

To optimize the surgical technique of the new extravesical seromuscular tunnel ureteroneocystostomy and to study the optimal relation between the length and width of the tunnel and the diameter of the normal and dilated ureters.

Methods

The optimized technique was applied to the left ureters of 20 dogs; 10 with normal ureters and 10 after induction of ureteral dilation. The new technique was performed to maintain a ratio of 3:1 between the width of the tunnel and the diameter of the ureter and a ratio of 1:1 between the length of the tunnel and the ureteral diameter. The results were compared with those for 5 dogs in which unilateral direct ureterovesical reimplantation was performed without an antireflux procedure. All the dogs were evaluated by intravenous urography, radioisotope renography, and ascending cystography before and at 1, 3, and 6 months after ureteroneocystostomy.

Results

All the dogs of the control group showed low-pressure vesicoureteral reflux and 3 demonstrated mild hydronephrosis and significant deterioration of the corresponding kidney. At 6-month follow-up, none of the 20 dogs subjected to the new technique showed deterioration of the function or configuration of the corresponding kidney. Moreover, the new technique was sufficient to prevent reflux in all but two dilated ureters that showed high-pressure vesicoureteral reflux.

Conclusions

For the extravesical seromuscular tunnel to be effective in reflux prevention without obstruction, the width of the tunnel must be triple the diameter of the ureter, and the length of the tunnel covering the intact (nonspatulated) part of the ureter should be equal to its diameter.  相似文献   
85.
Causes of infant deaths were analyzed from the linked vital records of 1988 for the District of Columbia. According to a new cause-of-death classification, 57% of the deaths were attributed to "prematurity and related conditions," as compared with only 31% due to "disorders relating to short gestation and unspecified low birthweight" and respiratory distress syndrome (RDS) in the three-digit ICD-9 classification. Two thirds of infant deaths were "preventable." However, 92% of these occurred to infants weighing less than 1500 g. Not only was a greater proportion of black deaths (71%) preventable as compared to nonblacks (40%), but also 15% of the preventable deaths among blacks were due to causes unrelated to prematurity. The Infant Mortality Rate (IMR) in the District of Columbia would be reduced from 23.2 to 7.7 if all preventable deaths were prevented, to 20.9 if only the preventable deaths not related to prematurity were prevented, and to 15.2 if the percentage of "preventable" deaths among blacks was brought down to the level of nonblacks. Mortality from RDS was substantially higher in the District of Columbia compared with blacks nationally and appeared to offer the best opportunity for reduction. However, detailed examination of circumstances surrounding each infant death would be necessary to inform the strategies for the reduction in IMR.  相似文献   
86.
Amyotrophic lateral sclerosis (ALS) is a paralytic disorder characterized by degeneration of large motor neurons of the brain and spinal cord. A subset of ALS is inherited (familial ALS, FALS) and is associated with more than 70 different mutations in the SOD1 gene. Here we report that lymphoblast cell lines derived from FALS patients with 16 different mutations in SOD1 gene exhibit significant increase of intracellular reactive oxygen species (ROS) compared with sporadic ALS (SALS) and normal controls (spouses of ALS patients). The ROS generation did not correlate with SOD1 activity. Further, cells incubated with vitamin C, catalase or the flavinoid quercetin significantly reduced ROS in all groups. The catalase inhibitor 3-amino-1,2,4-triazole resulted in a ten-fold increase of ROS in all groups. Neither L-nitroarginine, a nitric oxide synthase inhibitor or vitamin E altered the ROS levels. Thus, these studies suggest that hydrogen peroxide (H(2)O(2)) is a major ROS elevated in FALS lymphoblasts and it may contribute to the degeneration of susceptible cells. Further, we postulate a mechanism by which increased H(2)O(2) could be generated by mutant SOD1.  相似文献   
87.
88.
PURPOSE: We report our 4-year experience with deep dorsal vein arterialization at 3 years' follow-up in young patients with pure cavernoocclusive dysfunction as an alternative to penile prosthesis implantation. MATERIALS AND METHODS: We performed a modified Furlow-Fisher operation (circumflex collaterals are preserved and the deep dorsal venous valves are not disrupted by a stipper) in 25 patients who did not have risk factors such as general arteriosclerosis, coronary heart disease, hypertension, hyperlipidemia and age (over 40 years). Patients with arterial disease diagnosed by Doppler examination were excluded from the study. Also, patients with abnormal penile biothesiometric and electromyographic findings were not included in the study. Beside the subjective and objective evaluation the efficacy of the operation was also assessed retrospectively in 18 patients by telephone according to items 3 (ability to achieve an erection) and 4 (ability to maintain an erection) of the 15-item International Index of Erectile Function (IIEF). RESULTS: With a mean follow-up of 28 months (range 4-42) subjective and objective success rates were 80 and 72% at 1 year's 75 and 62.5% at 2 years', and 70 and 60% at 3 years' follow-up. According to items 3 and 4 of the 15 item IIEF questionnaire the mean postoperative scores reached 1.55-3.44 and 1. 33-3.27 for items 3 and 4, respectively (p<0.01). Two patients (8%) showed signs of glans hypervascularization as a major complication and minor complications such as penile skin edema, subdermal hematoma, loss of penile skin sensation and early thrombosis of the anastomosis were found in a total of 8 patients (32%). CONCLUSIONS: Deep dorsal vein arterialization is a preferable choice in highly selected young patients as an alternative to penile prosthesis.  相似文献   
89.
1 BACKGROUNDTheincidenceofCPis 0 .7per 1 0 0 0livebirths[1 ] .Becausecerebralpalsyinfluencesthewaychildrendevelop,itoftenresultsindevelop mentaldisability .Today ,more peoplehavecerebralpalsythananyotherdevelopmentaldis ability ,includingDownsyndrome,epilepsy ,andautism .Accordingtoasurveyconductedin1 986,2 .6%ofthepopulationofPakistaniaredisabled (includingbothphysicalandmentaldis abilities) .Childrenbetween 0~1 4 yearsinageconstitute 40 %ofthedisabled populationinPakistan .Routineme…  相似文献   
90.
Files of 8 patients with primary angiosarcomas treated in the Department of Radiation Oncology at the University of the Witwatersrand from 1982 to 1995 were identified. None of these patients had received prior radiotherapy or chemotherapy which would have predisposed them to the formation of an angiosarcoma. Slides of 6 patients were reviewed. Five of the 6 were confirmed as having angiosarcomas, while 1 patient was found to have a peripheral neuro-epithelial tumour. Four patients had angiosarcomas of the breast, while there was 1 patient each with angiosarcoma of the skin, intestine and brain. Complete excision was the primary modality of management whenever possible. Postoperative radiotherapy was given in cases of incomplete excision, patient refusal of radical surgery or gross tumour. Four patients died within 4 months of diagnosis. Three patients are alive (2 with no evidence of disease) 22-96 months after diagnosis. In 1 patient follow-up details were not available as he did not return for treatment. Angiosarcomas are aggressive malignant tumours arising from the endothelial cells. Complete surgical excision is the treatment of choice in the management of this aggressive disease, which has a poor prognosis.  相似文献   
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