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51.
A mandible from the Middle Pleistocene Hexian site and its significance in relation to the variability of Asian Homo erectus 下载免费PDF全文
52.
Alonso D Dorronsoro I Rubio L Muñoz P García-Palomero E Del Monte M Bidon-Chanal A Orozco M Luque FJ Castro A Medina M Martínez A 《Bioorganic & medicinal chemistry》2005,13(24):917-6597
A new series of donepezil–tacrine hybrid related derivatives have been synthesised as dual acetylcholinesterase inhibitors that could bind simultaneously to the peripheral and catalytic sites of the enzyme. These new hybrids combined a tacrine, 6-chlorotacrine or acridine unit as catalytic binding site and indanone (the heterocycle present in donepezil) or phthalimide moiety as peripheral binding site of the enzyme, connected through a different linker tether length. One of the synthesised compounds emerged as a potent and selective AChE inhibitor, which is able to displace propidium in a competition assay. These results seem to confirm the ability of this inhibitor to bind simultaneously to both sites of the enzyme and make it a promising lead for developing disease-modifying drugs for the future treatment of Alzheimer’s disease. To gain insight into the molecular determinants that modulate the inhibitory activity of these compounds, a molecular modelling study was performed to explore their binding to the enzyme. 相似文献
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D.A.M. da Silva M.S. Fernandes E.H. Endo A.C.P. Vital E.A. Britta M.E. Favero J.C. Castro P.T. Matumoto-Pintro B.P. Dias Filho C.V. Nakamura M. Machinski Junior J.M.G. Mikcha B.A. de Abreu Filho 《Letters in applied microbiology》2021,72(1):41-52
The use of rosemary essential oil (RO) and its combination with nisin (RO+N) in preventing the multiplication of Alicyclobacillus acidoterrestris in orange juice was evaluated. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for RO were both 125 μg ml−1 while RO+N displayed a synergistic effect. The use of RO and RO+N at concentrations of 1, 4 and 8× MIC in orange juice for 96 h was evaluated in terms of their sporicidal effectiveness. With regard to the action against A. acidoterrestris spores, RO at 8× MIC was sporostatic, whereas RO+N at 1× MIC was sporicidal. Morphological changes in the structure of the micro-organism after treatment were also observed by microscopy. Furthermore, flow cytometric analysis showed that most cells were damaged or killed after treatment. In general, the antioxidant activity after addition of RO+N decreased with time. The results demonstrate that using the combination of RO and nisin can prevent the A. acidoterrestris growth in orange juice. 相似文献
56.
Payo-Hill AL Dominguez RS Suarez MO Batista-Baez M Castro HT Rastrelli L Aquino R 《Phytochemistry》2000,54(8):927-932
A novel 3alpha,6beta,7beta-triol tropane alkaloid esterified by two benzoyl residues was isolated from the leaves of the endemic cuban species, Erythroxylon alaternifolium. Another novel 3alpha,6alpha,7beta-triol tropane alkaloid esterified by trimethoxycinnamoyl and trimethoxybenzoyl residues was isolated from the leaves and stem bark of a second endemic cuban species, Erythroxylon rotundifolium. Their structures were elucidated as 3alpha,7beta-dibenzoyloxy-6beta-hydroxy-tropane and 3alpha-(3,4,5-trimethoxycinnamoyloxy)-7beta-(3,4,5- trimethoxybenzoyloxy)-6alpha-hydroxy-tropane by spectroscopic methods including 2D-NMR techniques. 相似文献
57.
Mark S. Castro Keith N. Eshleman Louis F. Pitelka Geoff Frech Molly Ramsey William S. Currie Karen Kuers Jeffrey A. Simmons Bob R. Pohlad Carolyn L. Thomas David M. Johnson 《Biogeochemistry》2007,84(3):333-348
The objective of this study was to evaluate the nitrogen (N) biogeochemistry of an 18–22 year old forested watershed in western
Maryland. We hypothesized that this watershed should not exhibit symptoms of N saturation. This watershed was a strong source
of nitrate (NO3
−) to the stream in all years, with a mean annual export of 9.5 kg N ha−1 year−1 and a range of 4.4–18.4 kg N ha−1 year−1. During the 2001 and 2002 water years, wet deposition of inorganic N was 9.0 kg N ha−1 year−1 and 6.3 kg N ha−1 year−1, respectively. Watershed N export rates in 2001 and 2002 water years were 4.2 kg N ha−1 year−1 and 5.3 kg N ha−1 year−1, respectively. During the wetter water years of 2003 and 2004, the watershed exported 15.0 kg N ha−1 year−1 and 18.4 kg N ha−1 year−1, rates that exceeded annual wet deposition of N by a factor of two (7.5 kg N ha−1 year−1 in 2003) and three (5.5 kg N ha−1 year−1 in 2004). Consistent with the high rates of N export, were high concentrations (2.1–3.3%) of N in foliage, wood (0.3%) and
fine roots, low C:N ratios in the forest floor (17–24) and mineral soil (14), high percentages (83–96%) of the amount of mineralized
N that was nitrified and elevated N concentrations (up to 3 mg N l−1) in soil solution. Although this watershed contained a young aggrading forest, it exhibited several symptoms of N saturation
commonly observed in more mature forests. 相似文献
58.
Martin R. Ciancio Mariela C. Castro Fernando C. Galliari Alfredo A. Carlini Robert J. Asher 《Journal of Mammalian Evolution》2012,19(1):1-8
Late eruption of the permanent dentition was recently proposed as a shared anatomical feature of endemic African mammals (Afrotheria),
with anecdotal reports indicating that it is also present in dasypodids (armadillos). In order to clarify this question, and
address the possiblity that late eruption is shared by afrotherians and dasypodids, we quantified the eruption of permanent
teeth in Dasypus, focusing on growth series of D. hybridus and D. novemcinctus. This genus is the only known xenarthran that retains two functional generations of teeth. Its adult dentition typically
consists of eight upper and eight lower ever-growing (or euhypsodont) molariforms, with no premaxillary teeth. All but the
posterior-most tooth are replaced, consistent with the identification of a single molar locus in each series. Comparison of
dental replacement and skull metrics reveals that most specimens reach adult size with none or few erupted permanent teeth.
This pattern of growth occurring prior to the full eruption of the dentition is similar to that observed in most afrotherians.
The condition observed in Dasypus and many afrotherians differs from that of most other mammals, in which the permanent dentition erupts during (not after)
growth, and is complete at or near the attainment of sexual maturity and adult body size. The suture closure sequence of basicranial
and postcranial epiphyses does not correlate well with dental eruption. The basal phylogenetic position of the taxon within
dasypodids suggests that diphyodonty and late dental replacement represent the condition of early xenarthrans. Additionally,
the inferred reduction in the number of molars to a single locus and the multiplication of premolars represent rare features
for any living mammal, but may represent apomorphic characters for Dasypus. 相似文献
59.
Luís Eduardo Fernandes Rodrigues da Conceição Margarete Alice Fontes Saraiva Raphael Hermano Santos Diniz Juliana Oliveira Gustavo Dimas Barbosa Florencia Alvarez Lygia Fátima da Mata Correa Hygor Mezadri Mauricio Xavier Coutrim Robson José de Cássia Franco Afonso Candida Lucas Ieso Miranda Castro Rogelio Lopes Brandão 《Journal of industrial microbiology & biotechnology》2015,42(2):237-246