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71.
R Lagos P Herrera A Sepúlveda A Mu?oz C Benavente I Bravo T Lamberg 《Canadian Metallurgical Quarterly》1996,124(10):1211-1218
BACKGROUND: Urinary tract infections in children are associated with functional and anatomical abnormalities of the urinary tract, they tend to recur and can cause permanent kidney damage. AIM: To study in children with urinary tract infections, microbiological factors associated to recurrence, functional and anatomical abnormalities of the urinary tract. PATIENTS AND METHODS: A prospective sample of children was incorporated into a follow-up protocol after their first episode of bacteriologically-demonstrated urinary tract infection. In all patients an abdominal ultrasound examination and a mictional urethrocystography were done and the presence of fimbriae was studied in isolated strains of Escherichia coli. RESULTS: Two hundred fifteen cases bad an adequate adherence to the study protocol, 190 caused by E coli. Fimbriated E coli strains were isolated with greater frequency from children with pyelonephritis than from those with a low urinary tract infection (50 and 28% respectively). The absence of fimbriae in E coli strains was associated with a higher risk of recurrent infections (odds ratio = 3, confidence intervals = 2-9.2) and an abnormal urethrocystography (odds ratio = 3, confidence intervals = 1.1-10.2). CONCLUSIONS: These data are consistent with foreign reports and support the need to study adhesins in E coli strains isolated from children with urinary tract infections. 相似文献
72.
Keiko Shirai Guadalupe Pedraza Mercedes Gutierrez-Durn Valerie M E Marshall Sergio Revah-Moiseev Mariano García-Garibay 《Journal of the science of food and agriculture》1992,59(2):199-204
A mixed substrate composed of soya milk, oat flour and dried cheese whey (82, 11 and 7% respectively) had a content of lactose and protein similar to that of milk used for yogurt manufacture. Heat treatment for 20 min at 80°C resulted in a viscosity similar to that of yogurt whilst removing coliform and mesophilic aerobic bacteria, moulds and yeasts. Fermentation with traditional yogurt bacteria did not increase viscosity further, and the final product had similar acidity and texture to yogurt. Acid development, carbohydrate consumption, proteolysis and starters counts were followed during fermentation. The fermentation profile of the mixed substrate was very similar to that of milk. 相似文献
73.
74.
Pedro Pablo Fernández Guadalupe Préstamo Laura Otero Pedro D. Sanz 《European Food Research and Technology》2006,224(1):101-107
Pressure-shift freezing (PSF) is one of the most promising methods for obtaining high-quality frozen products. The aim of this work was to analyse the differences between broccoli that was frozen using two different PSF processes. In one of the processes, all the freezing was done inside the high-pressure vessel tempered at −20.5 °C. In the other process, the sample was taken out of the vessel after expansion, and freezing was completed using liquid N2. Colour, texture, electrical conductivity, microstructure and drip losses after centrifugation were analysed and a sensory test was performed. The results were compared with those for conventionally frozen broccoli purchased at the market. PSF broccoli presented less cell damage, lower drip losses and better texture than the market samples. The two different PSF processes assayed produced no significant differences in the final quality of the samples. 相似文献
75.
The Pick's disease categorization as a entity founded in its clinical presentation is a polemical matter of discussion between continental european and anglosaxon groups. We present a clinical case which support a characteristic pathochrony, anatomical localization and initial symptomatology of Pick's disease, which possibility its clinical differentiation with other dementias. 相似文献
76.
M Sargiacomo P Onori E Bravo A Franchitto A Cantafora S Barca C Peschle E Gaudio 《Canadian Metallurgical Quarterly》1998,28(3):480-490
BACKGROUND/AIMS: The present study describes an embryonic-fetal liver culture system which allows morphogenetic interactions consistent with the development of the hepatocellular function. METHODS: Intact livers from 8-12-week embryos were soaked in an extracellular matrix at 4 degrees C and gently dissociated without any enzymatic treatment. The resulting spherical hepatic units were cultured in a chemically defined serum-free medium and seeded into an extracellular matrix layer. Adherent three-dimensional tissue specimens were examined at various times by light and electron microscopy to evaluate the maintenance of hepatocyte morphology. RESULTS: The liver cells were viable for over 4 months; erythropoietic burst colonies were detected for longer than 6 weeks. Parallel detection of bile salt production in the medium by high performance liquid chromatography proved liver tissue functionality. Bile salt composition revealed predominance of taurine-conjugates rather than glycine. Maximum bile salt concentration (approximately 3 months) coincided with structural and ultrastructural observations indicating a marked decline in hematopoiesis, well-defined biliary canaliculi and formation of an organ-like structure. CONCLUSIONS: This three-dimensional culture system recapitulates fetal liver development with: (i) initial proliferation of both fetal erythropoietic and hepatic cells and (ii) subsequent shut-off of erythropoiesis and a shift to a more advanced stage of hepatocyte function, such as bile salt secretion. 相似文献
77.
78.
79.
Salvador H. Guzmán-Maldonado Ana L. Morales-Montelongo Candelario Mondragón-Jacobo Guadalupe Herrera-Hernández Fidel Guevara-Lara Rosalia Reynoso-Camacho 《Journal of food science》2010,75(6):C485-C492
Abstract: Xoconostle cv. Cuaresmeño (Opuntia matudae) has attracted domestic and international industry attention; however, variations of composition from xoconostle structures have not been evaluated. Industries discard the pulp (endocarp) and peel (pericarp) as wastes and utilize the skin (mesocarp), which is the edible portion. The physicochemical, nutritional, and functional characterization of structures from xoconostle pear from 3 major sites of production in Mexico were assessed. Skin yield ranged from 58% to 64% and was higher to that of peel (22% to 24%) and pulp (12% to 18%) yields. pH, °Brix, and acidity were similar among xoconostle structures. Total fiber showed by peel (18.23% to 20.37%) was 2-fold higher than that of skin. Protein and ether extract were higher in xoconostle pulp compared to that showed by peel and skin. Iron content of xoconostle peel (6 to 9.6 mg/100 g, DWB) was higher to that of skin and pulp and prickly pear pulp. Soluble phenols of peel (840 to 863 mg GAE/100 g, DWB) were almost similar to that of skin (919 to 986 mg GAE/100 g, dry weigh basis); meanwhile, ascorbic acid concentration of skin was 2-fold higher compared to that of peel. The phenolic fraction of xoconostle structures consisted of gallic, vanillic, and 4-hydroxybenzoic acids; catechin, epicatechin, and vanillin were also identified by high-performance liquid chromatography–didoe array detection (HPLC-DAD). Xoconostle peel showed higher antioxidant activity (TEAC) compared to that of skin (2-fold) and pulp (6-fold) of commonly consumed fruits and vegetables. The potential of xoconostle peel and pulp for the production of feed or food is promissory. Practical Application: Outstanding nutritional and functional properties of xoconostle cv. Cuaresmeño fruits are demonstrated. Increased consumption could contribute positively to improve the diet of rural and urban consumers. The high fiber, mineral, and antioxidant components of xoconostle peel and pulp suggest that these fruit structures, which are currently discarded as waste, have promissory use as feed or food by industry. 相似文献
80.
Rodrigo Loyola‐Sepulveda Gonzalo Lopez‐Leal Jorge Munoz Claudio Bravo‐Linares Stephen M. Mudge 《Water and Environment Journal》2009,23(4):286-292
Formation of trihalomethanes (THMs) during water disinfection has been related to several health problems, although the magnitude of these effects is under discussion. This paper quantifies the THMs in drinking water from the Bío‐Bío Region of central Chile, the first since the modification of the national reference value (Nch 409/05) to include maximal values for THMs. THMs were quantified using a solid phase micro‐extraction (SPME) method and GC‐MS. The concentration ranges were 9.7–111.6, 0.1–1.0 and 0.9–25.5 μg/L for chloroform (CHCl3), and dibromochloromethane (CHClBr2) and bromodichloromethane (CHCl2Br), respectively. Bromoform was not detected in any sample. There were good correlations (R2=0.91–0.98, P<0.001) between the THMs and the residence time of the water, the distance from the treatment plant and an inverse correlation to free chlorine in the water. The Additive Toxicity Index Value (0.07–1.00) showed that all samples were within the Chilean reference value for THMs in drinking water. However, several values were close to exceeding the maximum permitted concentration (200, 100, 100 and 60 μg/L for CHCl3, CHBr3, CHClBr2 and CHCl2Br, respectively), which may occur when the water demand is low and thus residence times are longer. 相似文献