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641.
Jordi Amblàs Novellas Joan Espaulella Panicot Carles Blay Pueyo Núria Molist Brunet Gianni E. Lucchetti d’Aniello Antoni Anglada Arisa Jordi Roca Casas 《Revista espa?ola de geriatría y gerontología》2013
Demographic changes and the economic situation of the recent years have conditioned a turning point in health policies, which have decided to progressively prioritize chronicity care programs. Given that hospital costs were concentrated in attention to patients with chronic diseases, reduction on admissions is now a priority target. 相似文献
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A34.5, a nonessential component of yeast RNA polymerase I, cooperates with subunit A14 and DNA topoisomerase I to produce a functional rRNA synthesis machine. 总被引:8,自引:4,他引:4
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O Gadal S Mariotte-Labarre S Chedin E Quemeneur C Carles A Sentenac P Thuriaux 《Molecular and cellular biology》1997,17(4):1787-1795
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During the austral summers of 2003 and 2006, two cruise were carried out in the Bellingshausen Sea and west off Antarctic
Peninsula on board of RV Hespérides. Samples were collected at 26 stations with a multinet Macer-GIROQ sled. A total of 557 cumaceans belonging to 36 species
of five families were collected. Nannastacidae was the most abundant and speciose family. Hemilamprops pellucidus and Cyclaspis gigas were the most frequently collected species (38.5% of sampling stations). Cumella asutralis reached the highest density (514.7 individuals/1,000 m2 at stn 7). Maximum species richness (S = 15) and diversity (H′ = 3.53) was observed at one of the deepest station. Positive correlations were found between the cumacean distribution and
the organic content and percentage of coarse sand of the sediments. Predominance of Nannastacidae in front of other cumaceans
could be explained by their type of feeding (i.e. predators or scavengers), which may be more successful in the deep seafloor
of an oligotrophic sea such as studied herein. The presence in the deepest sampling sites of species shared with faunas of
surrounding oceans suggests a link between these faunas and those of deep Antarctic waters. 相似文献
646.
A spatially structured linear model of the growth of intestinal bacteria is analysed from two generational viewpoints. Firstly, the basic reproduction number associated with the bacterial population, i.e. the expected number of daughter cells per bacterium, is given explicitly in terms of biological parameters. Secondly, an alternative quantity is introduced based on the number of bacteria produced within the intestine by one bacterium originally in the external media. The latter depends on the parameters in a simpler way and provides more biological insight than the standard reproduction number, allowing the design of experimental procedures. Both quantities coincide and are equal to one at the extinction threshold, below which the bacterial population becomes extinct. Optimal values of both reproduction numbers are derived assuming parameter trade-offs. 相似文献
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Iván Martínez-Monge Joan Albiol Martí Lecina Leticia Liste-Calleja Joan Miret Carles Solà Jordi J. Cairó 《Biotechnology and bioengineering》2019,116(2):388-404
At early stages of the exponential growth phase in HEK293 cell cultures, the tricarboxylic acid cycle is unable to process all the amount of NADH generated in the glycolysis pathway, being lactate the main by-product. However, HEK293 cells are also able to metabolize lactate depending on the environmental conditions. It has been recently observed that one of the most important modes of lactate metabolization is the cometabolism of lactate and glucose, observed even during the exponential growth phase. Extracellular lactate concentration and pH appear to be the key factors triggering the metabolic shift from glucose consumption and lactate production to lactate and glucose concomitant consumption. The hypothesis proposed for triggering this metabolic shift to lactate and glucose concomitant consumption is that HEK293 cells metabolize extracellular lactate as a response to both extracellular protons and lactate accumulation, by means of cotransporting them (extracellular protons and lactate) into the cytosol. At this point, there exists a considerable controversy about how lactate reaches the mitochondrial matrix: the first hypothesis proposes that lactate is converted into pyruvate in the cytosol, and afterward, pyruvate enters into the mitochondria; the second alternative considers that lactate enters first into the mitochondria, and then, is converted into pyruvate. In this study, lactate transport and metabolization into mitochondria is shown to be feasible, as evidenced by means of respirometry tests with isolated active mitochondria, including the depletion of lactate concentration of the respirometry assay. Although the capability of lactate metabolization by isolated mitochondria is demonstrated, the possibility of lactate being converted into pyruvate in the cytosol cannot be excluded from the discussion. For this reason, the calculation of the metabolic fluxes for an HEK293 cell line was performed for the different metabolic phases observed in batch cultures under pH controlled and noncontrolled conditions, considering both hypotheses. The main objective of this study is to evaluate the redistribution of cellular metabolism and compare the differences or similarities between the phases before and after the metabolic shift of HEK293 cells (shift observed when pH is not controlled). That is from a glucose consumption/lactate production phase to a glucose-lactate coconsumption phase. Interestingly, switching to a glucose and lactate cometabolization results in a better-balanced cell metabolism, with decreased glucose and amino acids uptake rates, affecting minimally cell growth. This behavior could be applied to further develop new approaches in terms of cell engineering and to develop improved cell culture strategies in the field of animal cell technology. 相似文献
648.
Santiago Castroviejo-Fisher Pontus Skoglund Raúl Valadez Carles Vilà Jennifer A Leonard 《BMC evolutionary biology》2011,11(1):73
Background
Dogs were an important element in many native American cultures at the time Europeans arrived. Although previous ancient DNA studies revealed the existence of unique native American mitochondrial sequences, these have not been found in modern dogs, mainly purebred, studied so far. 相似文献649.
Renuka R. Nayak Margaret Alexander Ishani Deshpande Kye Stapleton-Gray Bipin Rimal Andrew D. Patterson Carles Ubeda Jose U. Scher Peter J. Turnbaugh 《Cell host & microbe》2021,29(3):362-377.e11
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Slide Flask direct amniotic fluid culture enabling: to decrease the risk of abnormalities caused by the technique itself, to facilitate laboratory work, to shorten culture time (8 to 13 days). 相似文献