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81.
Constricting band penile injuries in children may be caused by inadvertent entrapment by a variety of agents including hair, thread, and circumcision dressings. Alternatively, the offending band may have been self-applied or applied by an attendant. Unrelieved, the band causes serious vascular occlusion, progressive tissue necrosis, and injury to the urethra and erectile tissue. We report a case of CBPI in a 12-year-old circumcised boy. The glans was attached to the penile shaft by a tenuous segment of tissue dorsally with complete transection of the urethra. A three-stage reconstruction using a delayed groin flap was successful.  相似文献   
82.
Fifty four patients presenting by huge splenomegaly were admitted to Tropical Medicine Department, El-Minia University Hospital. Tissue biopsy revealed pure bilharziasis due to S. hematobium in 10 (19%) cases, liver cirrhosis in 23 (42%), mixed schistosomiasis and cirrhosis in 8 (15%), hepatoma in 3 (6%), lymphoma in 6 (11%) and hematological diseases in the form of chronic myeloid leukemia in 2 (3.5%) and thalassemia major in 2 (3.5%) cases. The sensitivity and specificity of abdominal ultrasonography was 100% and 97% in cases of schistosomiasis, 100% and 100% in cases of hepatoma, 87% and 100% in cases of liver cirrhosis, 33% and 100% in cases of lymphoma respectively. There was a positive significant correlation between endoscopic variceal grading, portal vein diameter, splenic vein diameter, size of the spleen and the grading of the portal tract thickenings. The pathological and ultrasonographic diagnosis was the same in 38 (70%) cases. Splenogram was characteristic but not diagnostic in cases of schistosomiasis and liver cirrhosis. It was diagnostic and similar to peripheral blood picture in the 2 cases of chronic myeloid leukemia and was normal in cases of thalassemia major. Splenic aspiration was able to diagnose all cases of lymphomas. It can be considered as a useful adjunct to the usual diagnostic procedures, both in staging and follow up, especially in cases presenting only by splenomegaly.  相似文献   
83.
84.
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   
85.
86.
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   
87.

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   
88.
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   
89.
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   
90.
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