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951.
952.
Intrapericardial developmental foregut cysts are rare and are most frequently incidental findings at necropsy in adults. A 29 year old Asian woman delivered a 24 week stillborn fetus seven days after diagnosis of intrauterine death caused by rupture of a foregut cyst. Multiple cysts occupied the wall of the right atrium and its rupture caused haemopericardium and cardiac tamponade.  相似文献   
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Mental diseases such as schizophrenia are being modeled by artificial neural networks in an attempt to understand the underlying neuropathological processes. We studied hospitalized psychiatric patients that met the DSM-IIIR criteria for schizophrenia (N=19), and normal subjects with no psychiatric history (N=18). Performance on the Wisconsin Card Sorting Test (WCST) by schizophrenic patients was poorer than normal subjects as estimated by various scoring measurements. We then modeled an artificial neural network, motivated by biological considerations, that is able to simulate performance of normals and schizophrenics on the WCST. In order to model the complex nature of the WCST, we designed novel learning rules based on non-associative learning paradigms. We found that there must be a minimum amount of noise, or inherent synaptic instability, for our model to perform similar to schizophrenics.  相似文献   
956.
OBJECTIVE AND STUDY DESIGN: Successful adaptation to air breathing at birth depends on rapid absorption of fetal lung liquid that is mediated by activation of amiloride-sensitive sodium ion channels. To test the relationship between respiratory epithelial Na+ transport and development of respiratory distress syndrome (RDS), we measured nasal transepithelial potential difference (PD) in 31 very premature (< or = 30 weeks of gestation) newborn infants. Infants were retrospectively assigned to RDS (22 infants) and non-RDS (9 infants) groups on the basis of clinical and chest x-ray criteria. RESULTS: Maximal nasal epithelial PD increased with birth weight (-1.2 mV/100 gm) and was lower in infants with RDS (-16.5 +/- 0.6 mV) than in those without RDS (-22.0 +/- 1.3 mV). Infants without RDS had PD values similar to normal fullterm infants. Amiloride inhibition of PD, an index of Na+ absorption, was significantly lower, within the first 24 hours of life, in infants in whom RDS developed (3.8 +/- 0.2 mV; 29.5% +/- 0.8% inhibition) than in those without RDS (6.1 +/- 0.6 mV; 38.6% +/- 0.5% inhibition). Maximal and amiloride-sensitive PD returned to normal during the recovery phase of RDS. CONCLUSIONS: We conclude that Na+ absorption across nasal epithelium increases with increasing birth weight and that impairment of Na+ absorption across the respiratory epithelia of very premature infants may contribute to the pathogenesis of RDS.  相似文献   
957.
The authors relate their experience controlling an epidemic of meningitis which broke out in the refugee camps of the Goma region, in northern Zaire, after the dramatic events which had happened in Rwanda in April and June 1994. Out of the 348 cases of purulent meningitis diagnosed by the Bioforce team, meningococcal etiology was confirmed 327 times. The isolated meningococci were all of the serogroup A, serotype A; 4; P 1,9. They were resistant to streptomycin and to sulphamides. The epidemic lasted one month, touched people of all ages and spread progressively to all the camps. The epidemic surveillance set up meant that vaccination was carried out very quickly and the epidemic brought rapidly under control, even if other factors did intervene. All those called upon to intervene in such a context should be made aware of the interest of the basic triad to fight these epidemics: rapid vaccination, treatment of cases with oily chloramphenicol and bio-epidemiological surveillance.  相似文献   
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This article explores patterns of morbidity and comorbidity and their ability to predict functional disability among American Indian elders, using data from a sample of urban, rural off-reservation, and reservation Great Lakes American Indians age 55 and older. Higher rates are reported of a number of chronic illnesses than found in overall samples of U.S. elders. Results of multiple regression analyses predicting Instrumental Activities of Daily Living (IADLs) and Activities of Daily Living (ADLs) show age to be a consistent predictor of functional disabilities: The CMI (Index of Comorbidity) was found to be a more useful predictor of functional disability than was the simple summation of the number of chronic illnesses.  相似文献   
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