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41.
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A rise in the incidence of meningococcal disease has occurred in Spain in recent years, especially in some regions in the north-west of the country. Most cases have been caused by meningococci characterised as Neisseria meningitidis C:2b:P1.2,5. A total of 107 C:2b:P1.2,5 meningococcal isolates (60 from patients and 47 from carriers) and 12 isolates showing related antigenic combinations (C:2b:NST, C:2b:P1.2, C:2b:P1.5, C:NT:P1.2,5) was analysed by pulsed-field gel electrophoresis to determine the genetic variability of the epidemic and related strains. Endonucleases BglII and NheI were used to cut chromosomal DNA. When BglII was used, most of the C:2b:P1.2,5 isolates showed the same pulsotype regardless of whether they were from clinical cases or carriers. Isolates showing the principal profile after digestion with endonuclease BglII were analysed with NheI. Four pulsotypes were identified, of which two were found in only one isolate each. The major profiles (1 and 2) showed differential distribution among clinical and carrier isolates; pulsotype 1 was the most frequent among clinical isolates. However, the proportions of isolates showing profiles 1 and 2 were similar among carrier isolates. This could indicate that there are two variants of the C:2b:P1.2,5 strain with differing pathogenicity.  相似文献   
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Summary In this paper the survival and the histopathology of normal and thymectomized mice infected with some Arenoviruses is reported.Normal newborn mice infected intracerebrally with Junín, Machupo, Tacaribe and Amaparí virus showed similar histopathological changes in the central nervous system characterized by choroiditis, glial hyperplasia, vasculitis and perivasculitis with infiltration of lymphocytic cells.In thymectomized mice infected with Junín, Machupo and Tacaribe virus, there was no evidence of disease, survival reached almost 100% and no pathological alterations were observed in the brain.In contrast, thymectomized mice infected with Amaparí virus showed the same percentage of mortality and similar histopathological changes as non-thymectomized animals.This research was supported by Grant N 4908/71 from Consejo National de Investigaciones Cientificas y Técnicas, República Argentina, and by funds from Comisión Coordinadora para el estudio y lucha contra la Fiebre Hemorrágica Argentina de la Subseeretaría de Salud Pública, República Argentina.Chairman Department of Pathology, National Academy of Medicine, República Argentina.Members of Research Career from the Consejo Nacional de Investigaciones Cientificas y Técnicas, República Argentina.  相似文献   
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The changes in the content of the catecholamines in each structure of the geniculate and extrageniculate visual system of the rat during the aging period (6-30 months) have been studied. Dopamine was found at lower levels than noradrenaline in all the structures. The dopamine and noradrenaline showed different developmental profiles. Dopamine and its metabolite levels decreased in the lateral geniculate and visual cortex and increased in superior colliculus and posterior thalamus. Noradrenaline and its metabolites increased in all structures during the aging period. However, 3-methoxy-4-hydroxyphenylglycol/noradrenaline and normetanephrine/noradrenaline ratios decreased in all structures except in superior colliculus. These results suggest age-related changes in the catecholamines in the visual system of the rat.  相似文献   
47.
Isolated adducted thumbs is an uncommon malformation that occurs sporadically in the majority of cases although some affected families have been reported. Previously, autosomal dominant inheritance was suggested in two familial cases, but this mode of inheritance has not been confirmed. Here we describe a family with adducted thumbs and other digital anomalies in which seven members (six females and one male) are affected in three consecutive generations. Additionally, the patients showed mild abnormalities of fingers 2nd–4th bilaterally and hypoplasia of the middle phalanx of the 5th fingers. This family represents an autosomal dominant condition that apparently has not been previously reported.  相似文献   
48.
Single fiber electromyography (SFEMG) in mitochondrial diseases (MD)   总被引:1,自引:0,他引:1  
Conventional EMG, nerve conduction studies and SFEMG were performed in 18 patients with various phenotypes of MD. 14 cases showed findings consistent with mild myopathy, 2 patients signs of sensory-motor axonal neuropathy and 2 cases a mixture of myopathy and axonal neuropathy. Motor unit fiber density was mild increased in 8 out of 13 tested cases. Jitter was abnormal in 10 out of 18 tested patients. Jitter abnormalities were not related to myopathic or neurogenic features in the EMG study, and may be observed in muscles without clinical weakness. The results suggest the existence of neuromuscular transmission disturbances in patients with MD.  相似文献   
49.
We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015–2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens.  相似文献   
50.
Maternal and Child Health Journal - To identify and describe the frequency and characteristics of disrespect and abuse practices towards women during facility-based delivery in four hospitals in...  相似文献   
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