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991.
S. Mills C. Griffin O. O’Sullivan A. Coffey O.E. McAuliffe W.C. Meijer L.M. Serrano R.P. Ross 《International Dairy Journal》2011,21(12):963-969
Streptococcus thermophilus bacteriophage 5093 is a virulent phage that infects the industrial Mozzarella starter CSK939. The genome of phage 5093 is 37,184 base pairs (bps) containing 50 open reading frames (orfs). Genetic analysis revealed that the genome of phage 5093 is highly mosaic when compared with other sequenced S. thermophilus phages. This is particularly apparent in the late gene cluster with regions displaying high homology to prophage sequences of non-dairy streptococci and limited homology to either pac or cos-type S. thermophilus phages. In addition, a definitive antireceptor gene was not observed – suggesting that phage 5093 may have developed a different system for host recognition. Interestingly, the phage does contain a methylase domain that probably evolved as a phage counter-defence mechanism. These findings suggest that phage 5093 may represent a third group of S. thermophilus phage and provide the link between phages that infect S. thermophilus and its non-dairy ancestors. 相似文献
992.
Carla Del Carpio Jiménez Carlos Serrano Flores Jian He Quingguo Tian Steven J. Schwartz M. Mónica Giusti 《Food chemistry》2011
Berberis boliviana Lechler is a member of the Berberidaceae family that has a small edible red-purple berry. The plant is native to the Peruvian Andes and contains high amounts of anthocyanin pigments. The monomeric anthocyanin content, determined by a pH-differential method, was 7/100 g of seedless berries. Pigments were characterised by HPLC coupled to a photodiode array (PDA) and mass spectrophotometer (MS) detectors. Five aglycones and ten anthocyanins were found and identified as petunidin-3-glucoside (24.4%), delphinidin-3-glucoside (24.1%), malvidin-3-glucoside (22.1%), cyanidin-3-glucoside (10.2%), petunidin-3-rutinoside (7.15%), malvidin-3-rutinoside (4.9%), cyanidin-3-rutinoside (3.8%), delphinidin-3-rutinoside (2.6%), peonidin-3-glucoside (1.1%), and peonidin-3-rutinoside (0.9%). 相似文献
993.
Alkali-activated slag (AAS) binders are obtained by a manufacturing process less energy-intensive than ordinary Portland cement (OPC) and involves lower greenhouse gasses emission. These alkaline cements allow the production of high mechanical strength and durable concretes. In the present work, the adsorption of different superplasticizer admixtures (naphthalene-based, melamine-based and a vinyl copolymer) on the slag particles in AAS pastes using alkaline solutions with different pH values have been studied in detail. The effect of the superplasticizers on the yield stress and plastic viscosity of the AAS and OPC pastes have been also evaluated.The results obtained allowed us to conclude that the adsorption of the superplasticizers on AAS pastes is independent of the pH of the alkaline solutions used and lower than on OPC pastes. However, the effect of the admixtures on the rheological parameters depends directly on the type and dosage of the superplasticizer as well as of the binder used and, in the case of the AAS, on the pH of the alkaline activator solution. In 11.7-pH NaOH-AAS pastes the dosages of the superplasticizers required to attain similar reduction in the yield stress are ten-fold lower than for Portland cement. In this case the superplasticizers studied show a fluidizing effect considerably higher in 11.7-pH NaOH-AAS pastes than in OPC pastes. In 13.6-pH NaOH-AAS pastes, the only admixture observed to affect the rheological parameters is the naphthalene-based admixture due to its higher chemical stability in such extremely alkaline media. 相似文献
994.
R Colebunders P De Serrano A Van Gompel H Wynants K Blot E Van den Enden J Van den Ende 《Canadian Metallurgical Quarterly》1993,25(4):533-536
The objective of this study was to determine the effect of increasing quantities of zinc, administered with and without a meal, on zinc absorption. Fractional absorption of incremental quantities of zinc in four normal adults was determined by measuring fecal excretion of unabsorbed isotope on 3 consecutive days by using three different stable isotopes of zinc (67Zn, 68Zn, and 70Zn). Isotopes were administered in the post-absorptive state and, on a subsequent occasion, with a standard zinc-free breakfast. In the postabsorptive state, fractional absorption was not affected by the quantity of zinc ingested until this exceeded 5 mg. When the zinc was administered with a meal, however, fractional absorption of 3 and 5 mg was less than for 1 mg. These results are compatible with the hypothesis that exogenous dietary zinc has to compete for absorption with endogenous zinc that has been secreted into the lumen of the gastrointestinal tract in response to a meal. 相似文献
995.
Binucleate cells have been found in the glomerular zone of the adrenal cortex in rats subjected to low-sodium diets. By considering the various possibilities for their production, both the findings of nuclei in process of constriction and nuclei identical in form, confronted and smaller in size than those of neighbour cells, are in agreement with an amitotic nuclear division as the possible mechanism for the formation of these cells. 相似文献
996.
J de la Fuente M Rodríguez M Redondo C Montero JC García-García L Méndez E Serrano M Valdés A Enriquez M Canales E Ramos O Boué H Machado R Lleonart CA de Armas S Rey JL Rodríguez M Artiles L García 《Canadian Metallurgical Quarterly》1998,16(4):366-373
This study presents findings from an updated retrospective cohort mortality study of male police officers from January 1, 1950 to December 31, 1990 (n = 2,593; 58,474 person-years; 98% follow-up). Significantly higher than expected mortality rates were found for all cause mortality (Standardized mortality ratio [SMR] = 110; 95% confidence interval [95% CI] = 1.04-1.17), all malignant neoplasms (SMR = 125; 95% CI = 1.10-1.41), cancer of the esophagus (SMR = 213; 95% CI = 1.01-3.91), cancer of the colon (SMR = 187; 95% CI = 1.29-2.59), cancer of the kidney (SMR = 2.08, 95% CI = 100-3.82), Hodgkin's disease (SMR = 313; 95% CI = 1.01-7.29), cirrhosis of the liver (SMR = 150; 95% CI = 1.00-2.16), and suicide (SMR = 153; 95% CI = 1.00-2.24). All accidents were significantly lower (SMR = 53; 95% CI = 0.34-0.79). Mortality by years of police service showed higher than expected rates for (1) all malignant neoplasms in the 1- to 9-years-of-service group; (2) all causes, bladder cancer, leukemia, and arteriosclerotic heart disease in the 10 to 19-year group; and (3) colon cancer and cirrhosis of the liver in the over 30 years of service group. Hypotheses for findings are discussed. 相似文献
997.
This research focuses on the study of the stabilisation/solidification capacity of a cementing matrix, which has been made using alkali activation of fly ash, in the presence of toxic elements chromium and lead. Such capacity has been compared with that of Portland cement.Leaching tests carried out proved that this new matrix is able to stabilise and solidify lead in a very efficient way (analysed lead concentrations from leaching are in parts per billion). However, it does not present itself as efficient concerning chromium fixation since this element strongly disturbs the alkali-activation mechanism of the ash. 相似文献
998.
J Percodani E Serrano V Woisard JM Bachaud N Daly-Schveitzer JJ Pessey 《Canadian Metallurgical Quarterly》1996,113(4):212-218
We conducted a retrospective study of 34 patients treated by radical neck dissection followed by radiotherapy for one or several cervical adenopathies without a primary tumor. Mean follow-up was 48 months. During follow-up, 6 patients developed a presumed primary tumor, and 11 patients presented with recurrent lymph nodes. We found no statistically significant predictive factor, as to either clinical characteristics or the histological nature of the adenopathies. On the other hand, the number of metastatic lymph nodes found on the surgical specimen was correlated with the risk of lymph node recurrence. Among the prognostic factors with an unfavorable effect on survival, the dimensions of the adenopathy, its fixed characteristic and its TNM status, were identified. In this series, the appearance of a primary tumor did not seem to worsen the prognosis. On the other hand, the appearance of lymph node recurrence predicted poorer survival rates. The results are discussed and compared with those found in the literature. 相似文献
999.
INTRODUCTION: In complex partial crises (CPC) some characteristics of the way in which they occur may be helpful in localizing the focus of origin in the cerebral cortex. Thus, the appearance of any kind of status epilepticus will not predominate depending on the origin of the epileptic focus, but the complex partial state will be rare when the origin is temporal and more frequent when the origin is frontal. The appearance of CPC in a cluster form is, on the other hand, characteristic of crises originating in the frontal lobe. MATERIAL AND METHODS: We review the clinical history of 151 epileptics with CPC, evaluating the way in which the crises appear, together with other clinical data. We define the start of the crisis in a specific lobe, when this was the site of maximum voltage of the epileptic anomaly or of maximum phase opposition. RESULTS: 10% of the patients showed grouping of their CPC; in the remainder the appearance was isolated, 15% showed status epilepticus at some point in their illness. We found a statistical difference when relating this to the anomalous topography of the EEG; between 15% and 42% more patients with status epilepticus were counted when the topography of the anomaly in the EEG was extratemporal. There was also between 37.2% and 76.4% more patients with cluster crises in the cases with an extratemporal focus. 相似文献
1000.
A Schüller Pérez M Serrano Ríos 《Canadian Metallurgical Quarterly》1998,115(1):83-106; discussion 106-8