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排序方式: 共有1419条查询结果,搜索用时 15 毫秒
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Magnetic resonance images (MRIs) of the brains of 11 patients aged from 1 week to 12 years with a distinctive type of cerebral palsy were selected based on distribution of cerebral lesions, which were restricted to bilateral perirolandic cortical and subcortical regions, including frequent symmetric involvement of basal ganglia and ventrolateral nucleus of thalami. Retrospectively, the perinatal history and clinical features were reviewed to correlate clinical data with this distinctive pattern of brain injury. Clinically affected neonates had an encephalopathy associated with a severe perinatal asphyxial event. Older children with cerebral palsy survived a similar perinatal course and demonstrated spastic quadriparesis with bulbar or pseudobulbar involvement, lack of verbal speech and variable delays in cognitive development. The distribution of hypoxic-ischemic lesions involving bilateral perirolandic regions, basal ganglia, and thalami, appears to correlate with increased metabolic areas of primary myelination in full-term neonates, but not with arterial border zones nor a single cerebral artery distribution. Myelination is a critical process in maturing brain associated with marked increase in tissue respiration and thus greater susceptibility to oxygen deprivation. It is believed that the extent of hypoxic-ischemic brain injury is determined principally by brain maturity and regional metabolic rates at time of insult and this correlates with active myelination in full-term neonates. This study confirms previous data from neuropathologic literature and recent reports of neuroimaging studies of asphyxiated neonates. In addition, retrospective analysis of the clinical data enables recognition of a type of cerebral palsy that might be the hallmark of hypoxic-ischemic injury in term neonates. 相似文献
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MC Vila R Solà L Molina M Andreu S Coll J Gana J Marquez J Palá F Bory S Pons L Szescielinski W Jimenez 《Canadian Metallurgical Quarterly》1998,28(4):639-645
BACKGROUND/AIMS: In many centers paracentesis is considered the treatment of choice for tense ascites. However, the mechanism of effective hypovolemia after paracentesis, the main complication associated with this procedure, remains unknown. In the current study, systemic hemodynamics was sequentially studied before and after total paracentesis in 46 patients with cirrhosis and tense ascites. The aim of the study was to assess the mechanism of effective hypovolemia after paracentesis. METHODS: Plasma renin activity and aldosterone, mean arterial pressure, cardiac output (ECO-Doppler) and systemic vascular resistance were measured before, and 3 h, 6 h and 6 days after total paracentesis associated with plasma volume expansion. RESULTS: Effective hypovolemia after paracentesis (defined as 50% increase in plasma renin activity up to a level over 4 ng x m(-1) x h(-1) at the 6th day after paracentesis) occurred in 20 cases [plasma renin activity increased from 8+/-17 to 19+/-2.7 ng x m(-1) x h(-1)]. In the remaining 26 cases no changes in plasma renin activity [8.5+/-2.4 vs. 8.7+/-2.2 ng x m(-1) x h(-1)] were observed. The amounts of ascitic fluid volume removed were similar. Effective hypovolemia after paracentesis was associated with a significant decrease in mean arterial pressure (89+/-2 vs. 81+/-3 mmHg) and systemic vascular resistance [1263+/-67 vs. 1014+/-80 dyn x s(-1) x cm(-5)] 6 days after treatment. In contrast, no significant changes in these parameters were observed in patients not developing this complication. In the whole group of patients a significant inverse relation was observed between changes in plasma renin activity and in systemic vascular resistance (r=0.74;p< 0.001). CONCLUSIONS: These results indicate that effective hypovolemia after paracentesis in cirrhosis is predominantly due to an accentuation of the arteriolar vasodilation already present in these patients. 相似文献
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J Montaner A Mauleón C Vidal C Molina J Alvarez-Sabín 《Canadian Metallurgical Quarterly》1998,27(160):943-947
INTRODUCTION: Lack of awareness of warning signs of stroke is a factor that contribute to late patient arrival to the emergency department. OBJECTIVE: The goal of this pilot study was to determine the baseline knowledge of stroke among the population (terminology, signs-symptoms, risk factors and attitude) prior to educational campaigns. PATIENTS AND METHODS: A population-based interview using closed-ended questions was conducted by neurologists among 100 users of the Vall d'Hebron's Primary Health Center, randomly sampled. RESULTS: In our population a 9% unknowns totally the disease, of the remainder, 42% has a good knowledge of signs-symptoms and 46% of risk factors. Only 22% of the sample has good global knowledge of the disease. If suffering a stroke this population should seek medical attention through 911 (46.2%) or come directly to the emergency department (50.5%). If symptoms were gone away, transient ischemic attack (TIA), appears a trend to contact primary physicians (59.3%). Respondents aged > 65 years were less likely to recognize symptoms (p = 0.001) and to consider stroke as an emergency. Respondents with an affected relative (50.5%) tend to locate more exactly the disease at the brain (p = 0.05) and to arrive earlier to the emergency department (p = 0.045), than those with non-affected relatives. CONCLUSIONS: Less than a quarter of our population have a good knowledge of the disease. Stroke is considered an emergency unlike TIA. The information about stroke is theoretically associated with early presentation to the emergency department. These results permit a redesign of the questionnaire to conduct a second phase of the study and generalize them for the Spanish population. 相似文献
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This study tested Hispanic ethnicity and parent alcoholism as moderators of pubertal status effects on the parent-child relationship in a community sample of 421 boys and girls 11.5-16.5 years old. Ethnicity was a significant moderator: The direction of the puberty effect on parent support and parent-adolescent conflict differed for Hispanic (primarily Mexican American) and non-Hispanic White boys. Parent alcoholism did not moderate the effect of puberty, but there was more conflict and less support between children of alcoholics and their parents than between controls and their parents. Puberty effects on the parent-adolescent relationship were also found above and beyond the effects of chronological age. Future directions for research in this area are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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BA Stankiewicz PF Van Bergen IJ Duncan JF Carter DE Briggs RP Evershed 《Canadian Metallurgical Quarterly》1996,10(14):1747-1757
Flash pyrolysis/gas chromatography (py/GC) and py/GC/mass spectrometry (MS) have been utilized to characterize the cuticles of invertebrates chemically. Pyrolysis products have been identified and assigned to specific cuticular components. Acetylpyridones, acetamidofuran, 3-acetamido-5-methylfuran and 3-acetamido-(2 and 4)-pyrones are proposed as characteristic pyrolysis markers for chitin. Pyrolysis products displaying ions of m/z 70, 154, 168, 194 are thought to derive from diketopiperazine structures and provide potential markers for proteins and peptides in which proline, alanine, valine, arginine and glycine are the dominant amino acids. These products, constituting specific pyrolysis markers for invertebrate cuticles, may reflect the amino acid composition of their constituent structural proteins. The source of the various pyrolysis products of proteins has been verified by pyrolysis of reference proteins, peptides and amino acid mixtures. The presence of additional pyrolysis products related directly to histidine and catechol moieties is consistent with the chemical structure and composition proposed for arthropod cuticles based on recent work utilizing solid state 13C and 15N nuclear magnetic resonance. This study constitutes the first comprehensive chemical characterization of the pyrolysis products of invertebrate cuticles and provides the basis for future investigations requiring qualitative screening for cross-linked chitin and proteins in modern and fossil cuticles and in materials, e.g. geopolymers, that may be derived from them. 相似文献
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Althaus R Torres A Peris C Beltran MC Fernandez N Molina MP 《Journal of food protection》2003,66(3):473-478
The presence of drug residues in ewe's milk samples can be determined by microbial assays. The main limitation of these tests is the large number of false-positive results associated with them. False-positive results can be explained by the interaction of certain substances naturally existing in ewe's milk with the growth of the microorganism used in the test. In this study, milk chemical composition (fat, protein, lactose, total solids), somatic cell counts (SCCs), free fatty acid concentrations, and lactoperoxidase system components were determined in order to investigate their influence on the rate of false-positive results for the BRT and Delvotest microbiological inhibitor tests. Milk samples were obtained after morning milking of Manchega ewes at 15, 30, 45, 60, 75, 90, 105, 120, and 135 days after parturition. The animals did not receive any kind of treatment or medicated feed throughout the experiment. The false-positive rates for BRT and Delvotest were 3.75 and 2.4%, respectively. When the logistic regression model was applied, the percentages of total solids for positive samples were significantly different from those for negative samples (16.90 versus 18.42% for BRT, 16.05 versus 18.45% for Delvotest), while the SCC logarithmic transformation was significantly higher for the positive samples than for the negative samples (5.38 versus 5.11 log units for BRT, 5.32 versus 5.11 log units for Delvotest). Moreover, Delvotest-positive samples exhibited thiocyanate concentrations higher than those of Delvotest-negative samples (8.18 mg/liter versus 6.85 mg/liter). Further analyses are needed to confirm the possible presence of antimicrobial residues in this particular type of milk sample. 相似文献
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