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Two patients with infantile neuronal ceroid lipofuscinosis are presented whose clinical diagnosis was based on the typical clinical picture, together with absent sleep spindles and MRI findings (hypointense thalami and hyperintense periventricular white matter) as early as 18 months in one girl. In addition to a flat cortical SEP, these abnormalities appeared earlier than the typical ERG and VEP findings used previously for clinical diagnosis of this condition. MRI of the other patient showed the same changes and EEG sleep spindles were absent by two years.  相似文献   
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Abstract Salivary calcium was shown to be higher in treated periodontitis-affected subjects (P+) than in periodontitis-free patients (P?). Here the aim was to study whether differences in calcium or other salivary factors exist prior to treatment. The test group consisted of 20 (15 men, 5 women) periodontitis-affected subjects and the control group 15 subjects (10 men, 5 women) free from periodontitis. Paraffin-stimulated whole saliva was collected to determine the flow-rate, calcium and phosphate concentrations, pH, buffering capacity, numbers of mutans streptococci, lactobacilli and yeasts. The results showed a higher calcium concentration (p < 0.05) in the P+ group (x?: 1.68 mmol/l; SE: 0.06 in men and x?: 1.49 mmol/l; SE: 0.10 in women) than in the P-group (x?: 1.48 mmol/l; SE: 0.09 in men and x?: 1.18 mmol/l; SE: 0.10 in women). The P+ group had more intact teeth (x?±SE: 9.9±0.8 in men and 11.2±2.0 in women) than the P-group (x?± SE: 8.3±0.7 in men and 8.2±2.4 in women). The present findings may indicate that an elevated level of salivary Ca is characteristic of P+ patients both before and after periodontal treatment.  相似文献   
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Lymphatic vessels are essential for immune surveillance, tissue fluid homeostasis and fat absorption. Defects in lymphatic vessel formation or function cause lymphedema. Here we show that the vascular endothelial growth factor C (VEGF-C) is required for the initial steps in lymphatic development. In Vegfc-/- mice, endothelial cells commit to the lymphatic lineage but do not sprout to form lymph vessels. Sprouting was rescued by VEGF-C and VEGF-D but not by VEGF, indicating VEGF receptor 3 specificity. The lack of lymphatic vessels resulted in prenatal death due to fluid accumulation in tissues, and Vegfc+/- mice developed cutaneous lymphatic hypoplasia and lymphedema. Our results indicate that VEGF-C is the paracrine factor essential for lymphangiogenesis, and show that both Vegfc alleles are required for normal lymphatic development.  相似文献   
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Prevention Science - The long-term sustainment of bullying prevention programs has rarely been investigated. This study addresses this gap by identifying facilitators and barriers to the systematic...  相似文献   
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The EEG was recorded in 27 subjects during hangover. Male healthy volunteers drank 1.75 g/kg body weight of ethanol in 3 h and the EEG was recorded 14-16 h later when the degree of hangover was highest. For control purposes a second EEG was recorded after a similar session when subjects drank water instead of ethanol. A third record was taken in normal laboratory conditions. T5-A1 and O1-A1 derivations were subjected to computer analysis from which spectral and frequency parameters were calculated. Visual analysis of the EEG during hangover showed a decrease and slowing of alpha activity and an increase in theta activity. Spectral analysis of the EEG gave a statistically significant increase in 7-8 c/sec activity during hangover. The EEG change could not be explained in terms of blood alcohol level, hypoglycaemia or acidosis. Also fatigue could be excluded as a cause of EEG change by means of "water controls". The conclusion is that the slowing of the EEG during hangover is caused by the depressant action of ethanol, or its metabolites, on cortical function.  相似文献   
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We analyzed the developmental regulation and role of the neurotrophins during metanephric kidney morphogenesis. RNase protection assay revealed the presence of nerve growth factor, neurotrophin 3 (NT-3), and brain-derived neurotrophic factor mRNAs and the regulation of their expression during embryonic development of rat metanephros. NT-3 induced differentiation (neurite outgrowth) and survival (inhibition of apoptosis) of the neuronal precursors in cultured nephrogenic mesenchymes and neuronal differentiation in cultured whole kidneys, whereas NT-4/5, brain-derived neurotrophic factor, and nerve growth factor were without effect. The neurotrophins did not trigger tubular differentiation of isolated nephrogenic cells, which underwent apoptosis when cultured with or without the neurotrophins. NT-3 is thus an inducer of differentiation and a survival factor for renal neuronal cells, but none of the neurotrophins is a morphogen in kidney tubule induction.  相似文献   
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