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91.
92.
Giovanni De Stefano Piera Piacquadio Vito Sciancalepore 《Biotechnology Techniques》1996,10(11):857-860
Summary Potential application of metal-chelate regenerable carriers in food processing has been considered for lacease (EC. 1.10.3.2.) immobilization. Among the carriers tested, Sepharose 4B-Epi-IDA-Cu2+ with immobilized enzyme showed the highest activity towards phenolic compounds, removing 75 and 69% of catechin from model solutions eluted from the starting and regenerated carriers, respectively. These carriers were also characterized by high stability. 相似文献
93.
Maarten H. Jacobs Jerry J. Vaske Sara Dubois Piera Fehres 《European Journal of Wildlife Research》2014,60(4):589-598
Wolf populations have increased in Western Europe and North America. Lethal control of problem wolves is controversial and support varies among stakeholder groups. Knowing why people support or oppose policies can assist managers in dealing with the public. We examined the influence of emotions toward wolves on the acceptability of lethal wolf control. Two perspectives were used to classify emotions. The discrete perspective distinguishes qualitatively different emotions (e.g., fear, joy). The dimensional perspective differentiates emotions on the basis of valence and arousal. We conducted a survey among Dutch (n?=?369) and Canadian (n?=?208) university students. The independent variables were discrete emotions toward wolves (joy, fear, surprise, anger, disgust, sadness, interest) as well as valence and arousal. The dependent variables were acceptability of lethal control of wolves in three situations that reflect different problem levels (wolves present, wolves kill sheep, wolves kill human). Emotional dispositions toward wolves predicted up to 20 % of the variance of acceptability of lethal control. Disgust in both samples and joy in the Dutch sample were the best predictors. The predictive potential of fear was smaller and confined to two scenarios in the Dutch sample. Discrete emotions predicted acceptability better than valence and arousal. Emotions beyond fear should be considered in wildlife decision-making. 相似文献
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96.
Cranston A Carniti C Martin S Mondellini P Hooks Y Leyland J Hodgson S Clarke S Pierotti M Ponder BA Bongarzone I 《Molecular endocrinology (Baltimore, Md.)》2006,20(7):1633-1643
We report the finding of a novel missense mutation at codon 833 in the tyrosine kinase of the RET proto-oncogene in a patient with a carcinoma of the thyroid. In vitro experiments demonstrate that the R833C mutation induces transformed foci only when present in the long 3' splice isoform and, in keeping with a model in which the receptor has to dimerize to be completely activated, glial cell line-derived neurotrophic factor stimulation leads the RET(R833C) receptor to a higher level of activation. Tyrosine kinase assays show that the RET(R833C) long isoform has weak intrinsic kinase activity and phosphorylation of an exogenous substrate is not elevated even in the presence of glial cell line-derived neurotrophic factor. Furthermore, the R833C mutation is capable of sustaining the transformed phenotype in vivo but does not confer upon the transformed cells the ability to degrade the basement membrane in a manner analogous to metastasis. Our functional characterization of the R833C substitution suggests that, like the V804M and S891A mutations, this tyrosine kinase mutation confers a weak activating potential upon RET. This is the first report demonstrating that the introduction of an intracellular cysteine can activate RET. However, this does not occur via dimerization in a manner analogous to the extracellular cysteine mutants. 相似文献
97.
Self-pollination conditions have been recorded frequently in local populations of the genus Epipactis, and structural modifications have sometimes been reported, supporting taxonomic recognition of new species. As part of a survey of gynostemium micromorphology of Italian Epipactis populations, we studied an Apennine population of Epipactis microphylla (Ehrh.) Sw. a species listed as autogamous but with residual allogamous characters. In this population we observed the tendency to perform pre-anthesis cleistogamy. However, self-pollination was not a consequence of modification in column morphology. Cryptic pollen germination occurred in anther thecae or in the clinandrium, bypassing any contact with the receptive stigma. Pollen germination started from the distal pool of the pollinium, close to the rostellum-viscidium, suggesting that the rostellum-viscidium may have a function in promoting pollen-tube growth. Germinated pollen was exposed at the anthesis. 相似文献
98.
Laura A. Buttitta Alexia J. Katzaroff Bruce A. Edgar 《The Journal of cell biology》2010,189(6):981-996
Terminally differentiated cells in Drosophila melanogaster wings and eyes are largely resistant to proliferation upon deregulation of either E2F or cyclin E (CycE), but exogenous expression of both factors together can bypass cell cycle exit. In this study, we show this is the result of cooperation of cell cycle control mechanisms that limit E2F-CycE positive feedback and prevent cycling after terminal differentiation. Aberrant CycE activity after differentiation leads to the degradation of E2F activator complexes, which increases the proportion of CycE-resistant E2F repressor complexes, resulting in stable E2F target gene repression. If E2F-dependent repression is lost after differentiation, high anaphase-promoting complex/cyclosome (APC/C) activity degrades key E2F targets to limit cell cycle reentry. Providing both CycE and E2F activities bypasses exit by simultaneously inhibiting the APC/C and inducing a group of E2F target genes essential for cell cycle reentry after differentiation. These mechanisms are essential for proper development, as evading them leads to tissue outgrowths composed of dividing but terminally differentiated cells. 相似文献
99.
Gianfabio Giorgioni Francesco Claudi Sabrina Ruggieri Massimo Ricciutelli Giovanni F. Palmieri Antonio Di Stefano Piera Sozio Laura S. Cerasa Annalisa Chiavaroli Claudio Ferrante Giustino Orlando Richard A. Glennon 《Bioorganic & medicinal chemistry》2010,18(5):1834-1843
l-DOPA, the immediate biological precursor of dopamine, is still considered the drug of choice in the treatment of Parkinson’s disease. However, therapy with l-DOPA is associated with a number of acute problems. With the aim to increase the bioavailability after oral administration, we designed a multi-protected l-DOPA prodrugs able to release the drug by both spontaneous chemical or enzyme catalyzed hydrolysis. The new compounds have been synthesized and preliminarily evaluated for their water solubility, log P, chemical stability, and enzymatic stability. The results indicate that the incorporation of the amino acidic moiety of l-DOPA into an imidazoline-4-one ring provides prodrugs sufficiently stable to potentially cross unchanged the acidic environment of the stomach, and to be absorbed from the intestine. They also might be able to release l-DOPA in human plasma after enzymatic hydrolysis. The ability of prodrugs 6a–b to increase basal levels of striatal DA, and influence brain neurochemistry associated with dopaminergic activity following oral administration, as well as the radical-scavenging activity against DPPH for compounds 6a–b and 15a are also reported. 相似文献
100.
Noor Rain Abdullah Bridget E. Barber Timothy William Nor Azrina Norahmad Umi Rubiah Satsu Prem Kumar Muniandy Zakiah Ismail Matthew J. Grigg Jenarun Jelip Kim Piera Lorenz von Seidlein Tsin W. Yeo Nicholas M. Anstey Ric N. Price Sarah Auburn 《PloS one》2013,8(12)
Despite significant progress in the control of malaria in Malaysia, the complex transmission dynamics of P. vivax continue to challenge national efforts to achieve elimination. To assess the impact of ongoing interventions on P. vivax transmission dynamics in Sabah, we genotyped 9 short tandem repeat markers in a total of 97 isolates (8 recurrences) from across Sabah, with a focus on two districts, Kota Marudu (KM, n = 24) and Kota Kinabalu (KK, n = 21), over a 2 year period. STRUCTURE analysis on the Sabah-wide dataset demonstrated multiple sub-populations. Significant differentiation (F
ST = 0.243) was observed between KM and KK, located just 130 Km apart. Consistent with low endemic transmission, infection complexity was modest in both KM (mean MOI = 1.38) and KK (mean MOI = 1.19). However, population diversity remained moderate (H
E = 0.583 in KM and H
E = 0.667 in KK). Temporal trends revealed clonal expansions reflecting epidemic transmission dynamics. The haplotypes of these isolates declined in frequency over time, but persisted at low frequency throughout the study duration. A diverse array of low frequency isolates were detected in both KM and KK, some likely reflecting remnants of previous expansions. In accordance with clonal expansions, high levels of Linkage Disequilibrium (I
A
S >0.5 [P<0.0001] in KK and KM) declined sharply when identical haplotypes were represented once (I
A
S = 0.07 [P = 0.0076] in KM, and I
A
S = -0.003 [P = 0.606] in KK). All 8 recurrences, likely to be relapses, were homologous to the prior infection. These recurrences may promote the persistence of parasite lineages, sustaining local diversity. In summary, Sabah''s shrinking P. vivax population appears to have rendered this low endemic setting vulnerable to epidemic expansions. Migration may play an important role in the introduction of new parasite strains leading to epidemic expansions, with important implications for malaria elimination. 相似文献