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41.
A. Lafon E. J. Niklitschek J. Cornejo‐Donoso K. González 《Journal of fish biology》2010,76(4):1008-1014
Orange roughy Hoplostethus atlanticus juveniles <24 cm fork length (LF) (10–17 years old) were recorded for the first time in Chile, when 10 specimens were collected on the continental slope and seamount JF2 in Juan Fernandez Archipelago. The LF, total mass, anatomical and parasitological information are reported. Relevance to current life‐cycle hypotheses is discussed. 相似文献
42.
Our understanding of the evolution of the insulin signaling pathway (ISP) is still incomplete. One intriguing unanswered question is the explanation of the emergence of the glucostatic role of insulin in mammals. To find out whether this is due to the development of new sets of signaling transduction elements in these organisms, or to the establishment of new interactions between pre-existing proteins, we rebuilt putative orthologous ISPs in 17 eukaryotic organisms. Then, we computed the conservation of orthologous ISPs at different levels, from sequence similarity of orthologous proteins to co-evolution of interacting domains. We found that the emergence of glucostatic role in mammals can neither be explained by the development of new sets of signaling elements, nor by the establishment of new interactions between pre-existing proteins. The comparison of orthologous IRS molecules indicates that only in mammals have they acquired their complete functionality as efficient recruiters of effector sub-pathways. 相似文献
43.
González Tugas M Uslar Nawrath W Villarroel del Pino L Calderón Pinto J Palma Onetto C Carrasco Gorman M 《Revista espa?ola de geriatría y gerontología》2012,47(1):23-26
Introduction
Delirium is a common and serious complication in older patients, associated with increased, potentially preventable, morbidity and mortality. The aim of this study was to evaluate the associated costs of delirium during hospitalization in a university affiliated hospital in Chile.Materials and methods
Prospective cohort study of consecutive patients 65 years and older, admitted to a medical ward. A psychogeriatric team assessed patients during the first and every 48 h until discharge using the Confusion Assessment Method (CAM-S), length of hospital stay, pharmacy and total hospitalization costs were analyzed. Statistical analysis was performed using bivariate and multivariate analysis according to delirium diagnosis.Results
Data from 454 patients was analyzed, 160 of them in a delirium cohort (35.2%) and 294 in a non-delirium cohort (64.8%). The delirium cohort had a longer hospital stay (DATA) and higher mortality (7.0% versus 1.7%). The median of total costs of delirium during hospital stay was 38.7% higher than the non-delirium cohort (P < .001). Total costs were significantly higher in the delirium cohort after adjustment of covariables (P = .01).Conclusions
This study confirms that delirium is associated with significantly greater costs. Considering that effective delirium prevention is possible, the knowledge of associated costs can help health care providers to justify prevention strategies and finally give better care for older patients. 相似文献44.
J. J. González-Aguilera A. Ma. Fernández-Peralta 《Plant Systematics and Evolution》1981,139(1-2):147-154
The meiotic behaviour abnormalities, fertility and size of pollen of 6 taxa ofSesamoides have been analysed. Besides diploids (2x), polyploids (4x, 6x, 8x) have been found. The chromosome base number is x = 10, but an origin from x = 5 is suggested. 相似文献
45.
S Due?as-Carrera A Vi?a H E Garay O Reyes L Alvarez-Lajonchere I Guerra L J González J Morales 《The journal of peptide research》2001,58(3):221-228
Two variants of the hepatitis C virus (HCV) E2 envelope protein, lacking the C-terminal domain and comprising amino acids 458-650 (E2A) and 382-605 (E2C), respectively, were efficiently produced in BL21 (DE3) Escherichia coli cells. E2A and E2C were used to immunize mice. The E2C variant induced the maximal mean antibody titer. Anti-E2C mouse sera reacted mainly with E2 synthetic peptides covering the 70 amino acid N-terminal region of the E2 protein. Moreover, a panel of anti-HCV positive human sera recognized only the E2C protein (28.2%) and the synthetic peptide covering the HVR-1 of the E2 protein (23.1%). These data indicate the existence of an immunologically relevant region in the HVR-1 of the HCV E2 protein. 相似文献
46.
Alfredo Saldaña Christopher H. Lusk Wilfredo L. Gonzáles Ernesto Gianoli 《Evolutionary ecology》2007,21(5):651-662
Unlike other species of the genus Blechnum, the fern Blechnum chilense occurs in a wide range of habitats in Chilean temperate rainforest, from shaded forest understories to abandoned clearings
and large gaps. We asked if contrasting light environments can exert differential selection on ecophysiological traits of
B. chilense. We measured phenotypic selection on functional traits related to carbon gain: photosynthetic capacity (A
max), dark respiration rate (R
d), water use efficiency (WUE), leaf size and leaf thickness in populations growing in gaps and understorey environments. We
assessed survival until reproductive stage and fecundity (sporangia production) as fitness components. In order to determine
the potential evolutionary response of traits under selection, we estimated the genetic variation of these traits from clonally
propagated individuals in common garden experiments. In gaps, survival of B. chilense was positively correlated with WUE and negatively correlated with leaf size. In contrast, survival in shaded understories
was positively correlated with leaf size. We found positive directional fecundity selection on WUE in gaps population. In
understories, ferns of lower R
d and greater leaf size showed greater fecundity. Thus, whereas control of water loss was optimized in gaps, light capture
and net carbon balance were optimized in shaded understories. We found a significant genetic component of variation in WUE,
R
d and leaf size. This study shows the potential for evolutionary responses to heterogeneous light environments in functional
traits of B. chilense, a unique fern species able to occupy a broad successional niche in Chilean temperate rainforest. 相似文献
47.
One-tenth of Escherichia coli transconjugants resulting from the transfer of the catabolic plasmid pJP4 from Ralstonia eutropha JMP134 to E. coli XL1Blue, contained pJP4 derivatives with deletions (approximately 15-30 kb). The occurrence of these deletions is probably associated with the presence of Tn10 in the recipient. DNA endonuclease restriction analysis of the pJP4 deletion derivatives showed the absence of SphI and EcoRI fragments previously reported to hybridize with IncP Tra DNA probes. Moreover, these pJP4 deletion derivatives are not able to self-transfer, nor are they able to be mobilized. Accordingly, these pJP4 deletion derivatives lack transfer functions. 相似文献
48.
49.
50.
Rendal Vázquez ME Díaz Román TM Rodríguez Cabarcos M Zavanella Botta C Domenech García N González Cuesta M Sánchez Dopico MJ Pértega Díaz S Andión Núñez C 《Cell and tissue banking》2008,9(2):101-107
To analyse the influence of cold ischemic time (CIT) (2–24 h) and of cryopreservation (liquid phase) on the viability of the
valvular fibroblasts and in the presence of apoptosis. Cardiac valves from 10 pigs were evaluated by anatomo-pathological
study of the wall, muscle and leaflet. At the same time, the presence of cellular death due to apoptosis was investigated
in two ways; directly on tissue by Apodetec system and by two-colour flow cytometry assay analyzing a suspension of fibroblast
from valve leaflets using Anexina V and propidium iodure (PI). We established three groups of samples to compare different
experimental conditions: 2 h of ischemia (group 1), 24 h of ischemia (group 2), and a programme of cryopreservation (−1°C/min)
after 2 h of ischemia, followed by storage in liquid nitrogen during a week and thawing was performed (group 3). The analysis
of viabilities showed slight differences between all three groups. The results indicated CIT of 24 h undergoing more structural
affectation than CIT of 2 h. Flow cytometry analysis did not show important differences between groups; however cryopreserved
samples (group 3) slightly less viability and a higher percentage of death by apoptosis than group 1 and 2 using flow cytometry.
Apoptosis was confirmed on tissue from all valves but mainly in samples of group 2 and group 3. In summary, the viability
of the valves in the case of ischemic times of 2 h, 24 h or after cryopreservation/thawing differs slightly. The death of
the cells is mainly mediated by necrosis and not by apoptosis. 相似文献