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排序方式: 共有237条查询结果,搜索用时 187 毫秒
71.
Ivones Hernndez-Balmaseda Idania Rodeiro Guerra Ken Declerck Jos Alfredo Herrera Isidrn Claudina Prez-Novo Guy Van Camp Olivier De Wever Kethia Gonzlez Mayrel Labrada Adriana Carr Geovanni Dantas-Cassali Diego Carlos dos Reis Livan Delgado-Roche Roberto Rafael Nuez Ren Delgado-Hernndez Miguel David Fernndez Miriam T. Paz-Lopes Wim Vanden Berghe 《Marine drugs》2021,19(2)
72.
Janet Morffi Idania Rodeiro Sandra Luz Hernández Leonora González Jose Herrera J. Javier Espinosa-Aguirre 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):223-228
Mangifera indica stem bark extract (MSBE) is a Cuban natural product which has shown strong antioxidant properties. In this work, the antimutagenic effect of MSBE was tested against 10 well-known mutagens/carcinogens in the Ames test in the absence or presence of metabolic fraction (S9). The chemical mutagens tested included: cyclophosphamide, mitomycin C, bleomycin, cisplatin, dimethylnitrosamine (DMNA), benzo[a]pyrene (BP), 2-acetylaminofluorene (2-AAF), sodium azide, 1-nitropyrene (1-NP) and picrolonic acid. Protective effects of the extract were also evaluated by comparing the efficiency of S9 fraction obtained from rats treated during 28?days with oral doses of MSBE (50?C500?mg/kg) with that obtained from rats treated with vehicle (control) to activate bleomycin and cyclophosphamide in the Ames test. MSBE concentrations between 50 and 500???g/plate significantly reduced the mutagenicity mediated by all the chemicals tested with the exception of sodium azide. Higher mutagenicity was found when bleomycin and cyclophosphamide (CP) were activated by control S9 than by MSBE S9. In addition, inhibition of CYP1A1 microsomal activity was observed in the presence of MSBE (10?C20???g/ml). We can conclude that besides its potent antioxidant activity previously reported, MSBE may also exert a chemoprotective effect due to its capacity to inhibit CYP activity. 相似文献
73.
74.
Ana Rodiles Ester Santigosa Marcelino Herrera Ismael Hachero-Cruzado María Luisa Cordero Silvia Martínez-Llorens Santosh P. Lall Francisco Javier Alarcón 《Aquaculture International》2012,20(6):1053-1070
The effect of dietary protein level and protein source on growth and proteolytic activity of juvenile Solea senegalensis was studied. In Experiment 1, fish were fed on four experimental diets containing increased protein levels (36, 46, 56 and 67%). In Experiment 2, Senegalese soles were fed on five diets with partial substitution of fish meal by soybean meal, soybean protein concentrate, soybean protein isolate, wheat gluten meal or pea protein concentrate. Results prove that growth and proteolytic activity in the distal intestine of fish were affected by the quantitative increase in dietary protein. The origin of protein source used in the elaboration of experimental diets affected both the amount and composition of the alkaline proteases secreted into the intestinal lumen; however, it did not decrease animal growth. Juvenile Senegalese sole showed capability to modulate digestive protease secretion when the concentration and/or source of dietary protein were modified. Quantity and quality of dietary protein affected protein hydrolysis in Senegalese sole intestine. This study establishes that 30% fish meal protein can be replaced by soybean derivatives without affecting intestinal proteases. Replacement with wheat gluten meal or pea protein concentrate should be taken cautiously, but further research is needed to establish whether growth performance and digestive enzyme physiology of Senegalese sole are affected by plant protein-supplemented diets in a long-term trial. 相似文献
75.
Ismael Hachero‐Cruzado Pilar Olmo Beatriz Sánchez Marcelino Herrera Pedro Domingues 《Aquaculture Research》2012,43(10):1439-1450
The effects of two diets with different lipid composition (squid Loligo gahi and one commercial pellet for breeders) on reproductive performance and egg lipid composition of brill (Scophthalmus rhombus) were compared. A total of 36 adult brill weighing 1482 ± 432 g were randomly distributed in the experimental tanks. A flow‐through system composed of four tanks with 4.2 m2 of bottom area (5.0 m3 × 1.2 m water depth) was used. The experiment lasted for approximately 5 months (168 days). From the four mature females fed squid, three ovulated. Five females fed pellets matured and ovulated. Total ovulations were of 10 and 44, by the three females fed squid and the five ovulating female fed pellets respectively. Egg viability was higher, although not significantly, for females fed pellets. This indicates that pellets could be a better food for breeding females. In general, the egg total lipid content and the lipid classes composition did not seem to be affected by diet. In contrast, results indicate that not only diets but also individual females, regardless of the diet consumed, are determinant for egg fatty acid composition, clearly modulating their composition. 相似文献
76.
M. Guijarro G. PajaresP.J. Herrera X.P. Burgos-ArtizzuA. Ribeiro 《Computers and Electronics in Agriculture》2011,75(1):75-83
One important issue emerging strongly in agriculture is related with the automatization of tasks, where the optical sensors play an important role. They provide images that must be conveniently processed. The most relevant image processing procedures require the identification of green plants, in our experiments they come from barley and corn crops including weeds, so that some types of action can be carried out, including site-specific treatments with chemical products or mechanical manipulations. Also the identification of textures belonging to the soil could be useful to know some variables, such as humidity, smoothness or any others. Finally, from the point of view of the autonomous robot navigation, where the robot is equipped with the imaging system, some times it is convenient to know not only the soil information and the plants growing in the soil but also additional information supplied by global references based on specific areas. This implies that the images to be processed contain textures of three main types to be identified: green plants, soil and sky if any. This paper proposes a new automatic approach for segmenting these main textures and also to refine the identification of sub-textures inside the main ones. Concerning the green identification, we propose a new approach that exploits the performance of existing strategies by combining them. The combination takes into account the relevance of the information provided by each strategy based on the intensity variability. This makes an important contribution. The combination of thresholding approaches, for segmenting the soil and the sky, makes the second contribution; finally the adjusting of the supervised fuzzy clustering approach for identifying sub-textures automatically, makes the third finding. The performance of the method allows to verify its viability for automatic tasks in agriculture based on image processing. 相似文献
77.
Management effects on composition and dynamics of cutin and suberin in topsoil under agricultural use 下载免费PDF全文
C. M. Armas‐Herrera M.‐F. Dignac C. Rumpel C. D. Arbelo A. Chabbi 《European Journal of Soil Science》2016,67(4):360-373
We identified and quantified specific biomarkers of shoots and roots (cutin and suberin‐derived compounds, respectively) of three grassland species (Dactylis glomerata L., Festuca arundinacea Schreb. and Lolium perenne L.) in soil under different land use (grass, crop and bare soil) of the SOERE‐ACBB experimental site in Lusignan (France). We also investigated the fate of these markers in soil after conversion from grassland (C3 plants) to Zea mays L. (maize) (C4 plant) with natural 13C isotope abundances. Our results indicated that 9‐hydroxy hexadecanedioic acid and 8(9)(10),16‐dihydroxy hexadecanoic acid may be used as biomarkers for above‐ground biomass, whereas 1,22‐docosandioic acid, 22‐hydroxy docosanoic acid and 24‐hydroxy tetracosanoic acid might be the best below‐ground biomarkers for the plants investigated under the experimental conditions studied. The presence, concentration and shoot–root allocation pattern of these markers were different from those described for other species, which demonstrates the importance of verifying biomarker specificity for each species. Concentrations of cutin and suberin were largest in soil under maize and smallest under bare soil; this corresponded to the biomass added to the two soils. Suberin decreased by 40–64% and cutin by 24–40% during a 6‐year bare fallow, which indicates that root markers were more sensitive than shoot markers to degradation. Changes in 13C isotopic signatures of specific biomarkers after 6 years of maize showed a faster turnover of root than shoot biomarkers, in spite of the much smaller root inputs from maize than from grasses. The sequestration of suberin in soil was more rapid but less durable than that of cutin. 相似文献
78.
Gladys Romero Luisa M. Vásquez Philippe Lashermes Juan C. Herrera 《Plant Breeding》2014,133(1):121-129
Most of the commercial varieties of coffee (Coffea arabica L.) derived from the Timor hybrid (TH) have been shown to contain major genes for coffee leaf rust (CLR) resistance. To identify markers tightly linked to such genes, an F2 mapping population derived from a cross between ‘Caturra’ (susceptible variety) and the TH‐derived DI.200 line (highly resistant) was generated. Using expressed sequence information and a bioinformatics approach, both targeted region amplified polymorphism (TRAPs) markers and simple sequence repeat (SSR) markers were identified. Phenotypic evaluations in the field and under controlled conditions confirmed the existence of one quantitative trait locus for CLR resistance. Four candidate SSR markers were associated with high CLR resistance. They spanning a region of 2.5 cM designated QCLR_4 located within chromosome 4 of the international C. canephora map. The presence of this region was confirmed in a set of elite lines and commercial varieties. The QCLR_4 region corresponds to a new and genetically independent SH locus that could potentially be useful in gene pyramiding with other genes to enhance rust resistance in TH derivatives. 相似文献
79.
Nadeem Khan Shujun Zhou M. S. Ramanna Paul Arens Jeronimo Herrera Richard G. F. Visser Jaap M. Van Tuyl 《Euphytica》2009,166(3):399-409
Ploidy level and intergenomic recombination was studied in interspecific hybrids between Longiflorum × Asiatic lilies (LA
hybrid) backcross to Asiatic parents in order to assess the possibility for analytic breeding in lily. By backcrossing the
diploid (2n = 2x = 24) F1 interspecific hybrid between Longiflorum × Asiatic lilies to Asiatic parents, 104 BC1 progeny plants were produced.
Among these, there were 27 diploids, 73 triploids (2n = 2x = 36) and 4 aneuploids (2x − 1, 2x + 2 or 2x + 3). In addition, by backcrossing triploid BC1 (LAA) plants to diploid Asiatic parents in 2x − 3x and reciprocal combinations, 14 diploid BC2 progenies were produced. Genomic in situ hybridization (GISH) was performed to
study the intergenomic recombination and karyotype composition. GISH indicated extensive intergenomic recombination among
the chromosomes in LA hybrids. A large number of Longiflorum chromosomes were transmitted to the BC1 progenies from LA hybrids.
However, very few Longiflorum chromosomes were transmitted from the BC1 triploid (LAA) plants to the BC2 progenies. The occurrence
of diploid plants in the BC progenies of LA hybrids has opened the prospects of analytic breeding in lilies. In this approach,
the selection of superior genotypes can be carried out at the diploid level and polyploid forms are synthesized from superior
diploid parents. The advantages of analytic breeding are evident: (a) a maximum level of heterozygosity can be attained in
the synthetic polyploids and (b) introgression can be achieved with a minimum of linkage drag. Based on GISH results the potential
application of analytic breeding in lily allopolyploids has been discussed. 相似文献
80.
Astudillo-Vázquez A Dávalos Valle H De Jesús L Herrera G Navarrete A 《Fitoterapia》2008,79(7-8):577-580
Alternanthera repens and Bidens odorata are used as medication for gastrointestinal diseases today, mainly in relation to diarrhea; therefore, pharmacological tests with aqueous and ethanol extracts of both species were carried out in mice. Using charcoal meal, the activity of the four extracts on intestinal motility was determined, finding that they inhibit the advance of the gastrointestinal content. Also, the lethal media doses were estimated in order to examine the plants' safety. The data confirmed the validity of the medicinal use for both plant species, contributing to explain the use of these plants as antidiarrheal agents in Mexican traditional medicine. 相似文献