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Background Germinal matrix and intraventricular hemorrhage (GMH/IVH) is a known complication occurring in the first week of life in preterm neonates. However, the precise time of its occurrence and the ideal time to perform diagnostic imaging studies remain controversial. The purpose of this paper is to address these two issues in our patient population to allocate our resources to those at highest risk.Materials and methods This study included 282 premature newborns (under 37 weeks of gestation) that were admitted to our neonate ICU in a year’s time and screened for GMH/IVH. They were grouped in four categories according to their weight at birth, and according to their gestational age. All patients had a daily cranial ultrasound during the first week. It was then repeated once in the second week and once in the third.Results We found that the incidence of GMH/IVH among preterm neonates was 44.68%. It was inversely related to the weight and the age of the newborn. The onset of bleeding coordinated with the occurrence of hypoxia and respiratory distress requiring mechanical ventilation. The majorities occurred in the first 7 days of life; they were mostly grade I and II according to the Papule classification and silent for the most part. Complications were present in 41% of the survivors.  相似文献   
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Nevi with architectural disorder and cytologic atypia of melanocytes (NAD) (also called dysplastic nevi) have been controversial with regard to their relationship with melanoma risk and to their gradation in 3 degrees of atypia. Versican and the melanoma-associated proteoglycan (mel-CSPG) are 2 major proteoglycans expressed by malignant melanoma, and they have a role in the regulation of cell adhesion, migration, and differentiation. We evaluated the differences in versican and mel-CSPG expression in nevi, NAD with several degrees of atypia, and primary malignant melanoma. Immunoreactivity for versican was negative in benign melanocytic nevi, positive in NAD (ranging from weakly to intensely positive), and intensely positive in malignant melanoma. Immunostaining for mel-CSPG was negative in benign melanocytic nevi and mild to moderately positive in NAD and melanoma. Our results suggest that versican expression may be of value for distinguishing NAD from benign melanocytic nevi and for distinguishing severe NAD from mild and moderate NAD.  相似文献   
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Bulletin of Environmental Contamination and Toxicology - The application of Cu and CuO nanofertilizers in horticulture has been a promising strategy to promote plants’ growth. In our study,...  相似文献   
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OBJECTIVE: Prediction of neurologic outcome is difficult in neonates with acute nervous system injury. Previous studies using proton magnetic resonance spectroscopy ((1)H-MRS) have been used to predict short-term neurologic outcome in neonates with a variety of neurologic insults. We were interested in determining the effectiveness of combining clinical evaluation and spectroscopy obtained at the time of injury in predicting neurologic outcome at 24 months. STUDY DESIGN: We studied 33 neonates with acute central nervous system injury, 5.8+/-3.7 days of injury, owing to hypoxic-ischemic encephalopathy. Neonates were assessed using clinical variables (initial arterial pH, initial blood glucose, Sarnat score, electroencephalography) and spectroscopy (NAA/Cho, NAA/Cre, Cho/Cre, and lactate). Neonates were divided into two outcome groups: good/moderate and poor. Differences between the groups were assessed using chi(2) and t-test analyses. We analyzed the best predictors of outcome using discriminant analysis and calculated sensitivity, specificity, positive, and negative predictive values for each variable independently and in combination. RESULTS: There were significant differences between the good/moderate and poor outcome for the Sarnat score, EEG, lactate, and NAA/Cho. Spectroscopy combined with clinical variables improved sensitivity, but not specificity for predicting outcome. The presence of lactate had the best individual predictive value. Combination of the clinical with the MRS variables had the highest predictive value. CONCLUSION: Proton magnetic resonance spectroscopy done early after injury improves the ability to predict neurologic outcome at 24 months of age.  相似文献   
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