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Among some 7500 respondents with known place of birth who had completed a nationwide questionnaire survey for multiple sclerosis (MS) in France in 1986, there were 260 born in former French North Africa (Algeria, Morocco, Tunisia). They had migrated to France between 1923 and 1986, but 66% came between 1956 and 1964. Two-thirds were from Algeria, where virtually the entire European population had emigrated in 1962 at the end of the Algerian war for independence. The migrants were younger at prevalence day (mean 43.4 years) and at onset (29.4 years) than the French-born MS (46.6; 31.3 years). Eight migrants lacked age information. The 225 migrants with onset more than 1 year after immigration presumably acquired their MS in France. They provided an age adjusted (US 1960) MS prevalence rate 1.54 times that for all France. If the latter is taken at 50 per 100,000 population their estimated adjusted rate is 76.8 with 95% confidence interval of 67.1 to 87.5. The other 27 with presumed acquisition in North Africa gave an estimated adjusted prevalence of 16.6 per 100,000 (95% CI 10.9-24.1). For those migrants with acquisition in France there was a mean interval of 13 years between immigration or age 11 and clinical onset, with a minimum of 3 years. This series provides further support for the theses: 1) that MS is primarily an environmental disease acquired after childhood; 2) that acquisition requires prolonged or repeated exposure (here 3 years for these medium-to-high MS risk migrants) followed by a prolonged latent or incubation period between acquisition and symptom onset (here 10 years); and 3) that this disease is most likely a widespread but unknown persistent infection which results in clinical MS in only a small proportion of those affected.  相似文献   
33.
The chemical composition of volatile fraction, fixed oil and tegumental waxes of the seeds of two Helianthus annuus L. cultivars (Carlos and Florom 350) were examined by GC and GC–MS. Many qualitative and/or quantitative differences were observed. -Pinene, cis-verbenol and β-gurjunene were in both the main volatiles but with significant quantitative differences; moreover, Florom oil was characterized by a greater variety of constituents. The fixed oil and the waxes composition showed a general qualitative homogeneity, for both cultivars, even though marked quantitative differences were observable. The data obtained could be useful for the correct identification of the cultivars.  相似文献   
34.
OBJECTIVE: The Prechtl method of qualitative assessment of general movements (GMs) has been shown to be a good predictor of neurologic outcome in fetuses, preterm infants, and term infants. The aim of this study was to compare the results of this new technique with those of traditional neurologic examination and of cranial ultrasonography in preterm infants. METHODS: Serial videotape recordings (with off-line assessment of GMs), ultrasound examination of the brain, and neurologic examinations were performed from birth until about 6 months of corrected age, on a group of 66 preterm infants whose gestational age ranged from 26 to 36 weeks (mean 30.7 weeks). The agreement between the two techniques and their predictive power, with respect to the neurologic outcome at 2 years of corrected age, were evaluated for five different age groups from preterm age to 65 weeks of postmenstrual age. RESULTS: Overall agreement of the neurologic and GM findings was 80.3% and strongly age related (lower during the preterm and term periods and higher thereafter). At all ages the results of GM observation correlated highly with neurologic outcome; they showed higher sensitivity and specificity than the neurologic examination. This held true in particular before term age, when poor neurologic responses might be related to transient complications, and at term age, mainly because of infants with normal neurologic examination results but unfavorable outcome. During the preterm period the ultrasound results showed a better specificity and a lower sensitivity to outcome than GM findings. CONCLUSIONS: The results of this study indicate that quality assessment of GMs should be added to traditional neurologic assessment, neuroimaging, and other tests of preterm infants for diagnostic and prognostic purposes.  相似文献   
35.
The unc-51 gene, isolated from mutants of Caenorhabditis elegans exhibiting abnormal axonal extension and growth, encodes a novel serine/threonine kinase (K. Ogura, et al., 1994, Genes Dev. 8: 2389-2400). Here we report the molecular cloning and characterization of the human homologue of UNC-51, designated ULK1, for UNC-51 (C. elegans)-like kinase 1. Sequence analysis of the human ULK1 cDNA showed that an open reading frame is composed of 1050 amino acids with a calculated MW of 112.6 kDa and a pI of 8.80. Homology search analysis showed that ULK1 has 41% overall similarity to UNC-51 and 29% similarity to Apg1p of Saccharomyces cerevisiae. Phylogenetic analysis of ULK1, UNC-51, and Apglp suggested that they constitute a novel subfamily of serine/threonine kinases. Southern blot analyses suggested that the ULK1 gene spans 30-40 kb in the human genome as a single-copy gene. Zoo blot analysis indicated that ULK1 kinase is conserved among vertebrates including mammals, birds, reptiles, amphibians, and fish. Northern blot analysis revealed that ULK1 is ubiquitously expressed in adult human tissues such as skeletal muscle, heart, pancreas, brain, placenta, liver, kidney, and lung, whereas UNC-51 is specifically detected in the nervous system of C. elegans. Both FISH and RH mapping confirmed the regional localization of ULK1 to human chromosome 12q24.3.  相似文献   
36.
This article presents two cases in which an intraarticular fracture of the ulnar head occurred in association with a dorsal dislocation of the distal radioulnar joint. After open reduction and internal fixation of the osteochondral fragment, final outcomes were excellent.  相似文献   
37.
Since a long time, the Large Eddy Simulation (LES) concept is considered as a very promising candidate for advanced thermal hydraulic modeling in Nuclear Reactor Safety. This paper shows how LES is successfully applied in an industrial framework to free shear flows at high Reynolds numbers and to the associated transport of scalars (e.g. boron). Extensive verification and validation attempts towards this objective have already been performed for the Trio_U code ( [H?hne et al., 2006], [Bieder et al., 2007] and [Bieder and Graffard, 2007]). In the first part, this paper presents a short overview of what has been done for predicting the boron concentration at the core inlet under accident conditions. These calculations are then related to the demands of Best Practice Guidelines (BPG), which have been discussed by Mahaffy et al. (2007). It is shown, that high quality LES simulations for free sheer flows can be performed on tetrahedral meshes, what significantly simplifies the mesh generation procedure in topologically complex geometries. Guidelines specifically devoted to the LES framework are proposed to analyse the capability of numerical schemes to treat correctly the scalar transport.  相似文献   
38.
We investigate and compare, over the additive white Gaussian noise channel, different options for updating the error correcting code currently used in space mission telecommand links. Besides some more consolidated proposals, using low‐density parity‐check codes, we characterize and assess the performance of alternative schemes, based on parallel turbo codes and soft‐decision decoded Bose‐Chaudhuri‐Hocquenghem (BCH) codes. The analysis considers relevant metrics like the codeword error rate, the frame error rate, and the undetected frame error rate. The considered codes include binary and non‐binary low‐density parity‐check codes, parallel turbo codes and extended BCH codes, with different decoding algorithms. The complexity of the various schemes and possible limits for their application are considered and discussed. Several numerical examples are provided. International Journal of Satellite Communications and Networking. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
39.
The yeast Saccharomyces cerevisiae is commonly employed in industrial ethanol production, regardless of the capability of Kluyveromyces marxianus strains to produce ethanol at similar or higher levels and on inhibitory conditions. Therefore, in this work strains of S. cerevisiae (ethanol RED and AR5) and K. marxianus (SLP1 and OFF1) were compared for ethanol production from sugarcane bagasse (SCB) and wheat straw (WS) hydrolysates. As it is known, during the lignocellulosic hydrolysis not only free sugars were obtained (SCB, g L?1: glucose 7.64, xylose 8.38, arabinose 2.43; and WS, g L?1: glucose 6.07, xylose 6.36, arabinose 2.09) but also growth inhibitors of yeast such as hydroxymethylfurfural and furfural that could modify the fermentation capability. The volumetric ethanol productivity (Q p) was evaluated, and it was observed that the K. marxianus SLP1 was the most efficient for ethanol production reaching a Q p of 0.292 and 0.250 g L?1 h?1 on SCB and WS hydrolysates, respectively. In contrast, S. cerevisiae AR5 and ethanol RED exhibited a reduced Q p on SCB, but similar values of Q p to K. marxianus OFF1 on WS. The results obtained show that it is possible to select K. marxianus yeast strains for ethanol production using SCB and WS hydrolysates obtaining higher Q p than S. cerevisiae yeast strains. Considering the efficiency of ethanol production and the tolerance to inhibitors, K. marxianus strain SLP1 possesses a great potential as an industrial yeast for lignocellulosic ethanol production.  相似文献   
40.
This paper deals with a numerical study of a pebble bed reactor. The calculations are performed with the Trio_U/Priceles code. The results obtained with the Boussinesq approximation and the quasi-compressible model are compared. It is seen that the expanding effect are important. The quasi-compressible model leads to a lower maximum value for the temperature field. The maximum pressure difference is detected when the density variations are taken into account.  相似文献   
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