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61.
J Colomer Oferil J López-Castillo P Poo Argüelles J Vila Torres E Fernández-Alvarez 《Canadian Metallurgical Quarterly》1993,39(6):517-520
Three new cases of two different forms of congenital nemaline myopathy are reported. Two of them represent a severe neonatal form. These cases were presented as a floppy infant syndrome. Although neither of them needed intensive care, they had feeding difficulties and one needed a feeding-tube for a period of time. Both of the patients showed a very severe motor delay and neither could manage to walk independently. During their lives, they suffered from repeated pneumonias, which was the cause of death in both cases before the age of two years. The mild congenital type represents a more benign form. Although hypotonic and weak, the patient managed to walk independently before two years of age. The weakness was spread all over, but was focused in the face, extensors of the neck and axial muscles. At 9 years of age, the patient has not experienced any respiratory trouble. The CK (creatine kinase) test were normal in all patients, but the EMG (electromyogram) showed different electromyographic patterns. The rods were in subsarcolemic positions, cytoplasmic positions or in both positions. 相似文献
62.
In this study, it is presented for the first time, the characterization of an amorphous polyamide after having been subjected to humid thermal conditions such as those typically applied in the industrial sterilization of packaged foods. From a fundamental point of view, it was fortuitously found that the combination of heat and moisture, with and without the assistance of pressure, was capable of inducing some crystallization in the otherwise amorphous polymer. Characterization of the crystallization process was carried out by differential scanning calorimetry, Fourier transform infrared, and simultaneous time‐resolved small and wide angle X‐ray scattering synchrotron experiments. The crystallization of the polymer began as characterized by wide angle X‐ray scattering and differential scanning calorimetry in the presence of humidity at ~90°C and extended up to 120°C under autoclave conditions, and it is thought to be the result of heated moisture being able to disrupt the intense amide groups self‐association. Thus, the thermally activated molecular structure is thought to become plasticized by the combined presence of heat and water which, in turn, provoke sufficient segmental molecular mobility in the system to promote some degree of lateral order. Propertywise, the resulting consequences of this behavior are an increase in the barrier properties to oxygen and a reduction in water sorption. From an applied view point, it is suggested that this unexpected behavior could make this polymer of significant interest in retortable food packaging applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1216–1223, 2006 相似文献
63.
Luc van Dyck Amparo Pascual-Ahuir Benedicte Purnelle Andre Goffeau 《Yeast (Chichester, England)》1995,11(10):987-991
64.
A model is proposed for dealing with decision-making problems in which the decision maker has a vague (linguistically assessed) and incomplete information about results and external factors (a quite usual situation in real decision cases). It is assumed here that utilities are evaluated in a term set of labels and the incomplete information is supposed to be a partial linguistic assignment of probability with values on a term set of linguistic likelihoods. the first step is to discuss a well-fitted interpretation of that model. After that, basic decision rules based on fuzzy risk intervals are developed. Additionally the suitability of considering a hierarchical structure (represented by a tree) for the set of utility labels is analyzed. © 1994 John Wiley & Sons, Inc. 相似文献
65.
We present Calcium3D, a user-friendly software package for simulating calcium triggered processes in neuroendocrine cells. We use Monte Carlo methods for the simulation of the basic processes involved: entry of calcium into the cytoplasm, the diffusion of ions and mobile intracellular calcium buffers inside the intracellular medium, and the kinetics of the reaction of calcium with these buffers. The outputs of the simulation are calcium and buffer concentrations as a function of time and for different depths from the cellular membrane. 相似文献
66.
P Isnard-Mugnier G Vila C Nollet-Clemencon L Vera G Rault MC Mouren-Simeoni 《Canadian Metallurgical Quarterly》1993,50(6):479-484
BACKGROUND: Obesity is a major Public Health problem in developed countries. It is frequently associated with psychological difficulties that may interfere with treatment. PATIENTS AND METHODS: 22 obese female adolescents, aged 13 to 19 years, and 24 age-matched female controls, were compared with regard to emotional pathology (anxiety, depression), eating behaviors, self-esteem, body image and parental history of depression. The evaluation was both categorical (DSM III-R criteria) and dimensional for depression and anxiety. It also included a self-esteem scale and questionnaires. RESULTS: The obese adolescents had more depressive symptoms, more prevalent anxiety disorders, more frequent histories of parental depression, eating behaviors characterized by over-eating and/or restricted intake, lower self-esteem and dissatisfaction with their body image, leading to avoidance behaviors in some of them. CONCLUSIONS: Psychological manifestations, although they are still insufficiently documented, especially in adolescents, may aggravate obesity and interfere with treatment. 相似文献
67.
Aung K. Htoon Surjani Uthayakumaran Udayasika Piyasiri Ingrid A.M. Appelqvist Amparo López-Rubio Elliot P. Gilbert Roger J. Mulder 《Food chemistry》2010
The enzyme-resistant starch (ERS) content in processed high amylose and regular maize starches has been studied, with and without acid dextrinisation. The physicochemical and structural characteristics of the starches were analysed using a variety of techniques. The increase in ERS in high amylose maize starch with dextrinisation was related to the formation of a critical molecular weight fraction (MW ∼ 20,000) that could rearrange structurally. Further dextrinisation reduced the processed starch MW to below where it could still form ERS. Regular maize starch containing less than 30% amylose did not increase its resistance to amylase digestibility with acid dextrinisation, probably due to impairment of amylose rearrangement by the numerous branched amylopectin chains. The ERS, which is likely to form during the enzyme-digestion process, is a linear molecule with a maximum degree of polymerisation (DP) of 30, irrespective of the starch source, processing conditions applied or type and amount of acid used. 相似文献
68.
AnaM. Lozano Vila Stijn Monsaert Renata Drozdzak Stanislaw Wolowiec Francis Verpoort 《Advanced Synthesis \u0026amp; Catalysis》2009,351(16):2689-2701
We here report on the stability and catalytic activity of new indenylidene‐Schiff base‐ruthenium complexes 3a – f through representative cross‐metathesis (CM) and ring‐closing metathesis (RCM) reactions. Excellent activity of the new complexes was found for the two selected RCM reactions; prominent conversion was obtained compared to the commercial Hoveyda–Grubbs catalyst 2 . Moreover, excellent results were obtained for a standard CM reaction. Higher conversions were achieved with one of the indenylidene catalysts compared with Hoveyda–Grubbs catalyst. Unexpectedly, an isomerization reaction was observed during the CM reaction of allylbenzene. To the best of our knowledge, isomerization reactions in this model CM reaction in closed systems have never been described using first generation catalysts, including the Hoveyda–Grubbs catalyst. The first model CM reactions as well as the RCM reactions have been monitored using 1H NMR. The course of the CM reaction of 3‐phenylprop‐1‐ene ( 8 ) and cis‐1,4‐diacetoxybut‐2‐ene ( 9 ) was monitored by GC. The isomerization reaction was studied by means of GC‐mass spectrometry and in situ IR spectroscopy. All catalysts were structurally characterized by means of 1H, 13C, and 31P NMR spectroscopy. 相似文献
69.
70.
Belloch C Orlic S Barrio E Querol A 《International journal of food microbiology》2008,122(1-2):188-195
Along the fermentation process yeasts are affected by a succession of stress conditions that affect their viability and fermentation efficiency. Among the stress conditions the most relevant are high sugar concentration and low pH in musts, temperature and, as fermentation progresses, ethanol accumulation. Nowadays, due to the demanding nature of modern winemaking practices and sophisticated wine markets, there is an ever-growing search for particular wine yeast strains possessing a wide range of optimized, improved or novel enological characteristics. Traditionally, the species S. cerevisiae and S. bayanus within the Saccharomyces sensu stricto species are considered some of the most important yeast species involved in fermentation processes. However, in the last years, hybrid strains between the species S. cerevisiae, S. bayanus and S. kudriavzevii have been described as yeasts conducting the alcoholic fermentations and some of them are commercially available. Our results indicate that yeasts in the Saccharomyces sensu stricto complex were not affected by low pH or high glucose content in the media; however temperature and ethanol concentration variables appreciably affected their growth. The strains pertaining to S. cerevisiae were able to tolerate high temperature stress, whereas strains within S. bayanus and S. kudriavzevii were better adapted to growth at lower temperatures. Regarding to alcohol tolerance, S. cerevisiae is tolerating alcohol better than S. bayanus or S. kudriavzevii. Surprisingly, the natural hybrids between these species have adapted to growth under ethanol and temperature stress by inheriting competitive traits from one or another parental species. These results open new perspectives in the construction of new hybrid strains with biotechnological interest, as the characteristics of the parents may result in interesting combinations in the hybrids. 相似文献