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61.
de Azevedo Pereira R Valencia-Jiménez A Magalhães CP Prates MV Melo JA de Lima LM de Sales MP Tempel Nakasu EY da Silva MC Grossi-de-Sá MF 《Journal of agricultural and food chemistry》2007,55(26):10714-10719
The coffee berry borer, Hypothenemus hampei (Ferrari), is an important devastating coffee pest worldwide. Both trypsin and chymotrypsin enzyme activities from H. hampei larval midgut can be inactivated by proteinaceous enzyme-inhibitors. A serine proteinase inhibitor belonging to the Bowman-Birk class was purified from a wild accession of Phaseolus coccineus L. seeds. The inhibitor (PcBBI1) is a cysteine-rich protein that is heat-stable at alkaline pH. MALDI-TOF/MS analysis showed that PcBBI1 occurs in seeds as a monomer (8689 Da) or dimer (17,378 Da). Using in vitro inhibition assays, it was found that PcBBI1 has a high inhibitory activity against H. hampei trypsin-like enzymes, bovine pancreatic chymotrypsin, and trypsin. According to this, PcBBI1 could be a promising tool to make genetically modified coffee with resistance to coffee berry borer. 相似文献
62.
This study aimed at capturing the spatial variability of landscape patterns and their trajectories of change from 1950 to
2000 within a watershed, which is representative of areas of intensive agricultural use. After an analysis of landscape features
changes for the entire watershed based on aerial photographs, hierarchical clustering analysis provided a typology of landscape
patterns for the cadastral lots. Following that, the trajectory of change of each lot was characterized (nature, importance,
direction, rate of change). Seven types of landscape patterns are distinguished by the relative importance of different classes
of landscape features and 51 trajectories of change were identified for the lots. The analysis shows that although the majority
of lots were subjected to a homogenization of their landscape patterns since 1950, this trend is not entirely uniform and
that since 2000 it occurs alongside trends towards diversification of certain landscape features on some lots. Furthermore,
nearly a third of the lots are not following the main trajectories of change detected. Thus, the results suggest that extrinsic
forces (policies, technologies) that are directing main changes in areas of intensive agricultural use toward uniformity could
be modulated by internal forces (uses and values of the population). A better understanding of theses internal forces seems
crucial to manage landscapes. From a methodology standpoint, although the hierarchical clustering analyses appear useful for
understanding the spatial and temporal variability of landscape patterns, particular attention must be given to validating
the typology chosen to characterize them. 相似文献
63.
Teschner D Borsodi J Wootsch A Révay Z Hävecker M Knop-Gericke A Jackson SD Schlögl R 《Science (New York, N.Y.)》2008,320(5872):86-89
Alkynes can be selectively hydrogenated into alkenes on solid palladium catalysts. This process requires a strong modification of the near-surface region of palladium, in which carbon (from fragmented feed molecules) occupies interstitial lattice sites. In situ x-ray photoelectron spectroscopic measurements under reaction conditions indicated that much less carbon was dissolved in palladium during unselective, total hydrogenation. Additional studies of hydrogen content using in situ prompt gamma activation analysis, which allowed us to follow the hydrogen content of palladium during catalysis, indicated that unselective hydrogenation proceeds on hydrogen-saturated beta-hydride, whereas selective hydrogenation was only possible after decoupling bulk properties from the surface events. Thus, the population of subsurface sites of palladium, by either hydrogen or carbon, governs the hydrogenation events on the surface. 相似文献
64.
Ibern-Gómez M Roig-Pérez S Lamuela-Raventós RM de la Torre-Boronat MC 《Journal of agricultural and food chemistry》2000,48(12):6352-6354
Peanut and its derivatives, especially peanut butter, are extensively consumed in many countries, mainly in the United States, which is also the major exporter of these products. trans-Resveratrol is present in peanuts, and recently this compound has been quantified in peanut butter. It is well-known that there are beneficial effects of trans-resveratrol and its glucoside, the piceid, in health. The absorption of trans-resveratrol has been proven in animals, and certain studies show that the absorption of some phenols is enhanced by conjugation with glucose, so that it could be possible that trans-piceid would be more absorbed than its aglycon (trans-resveratrol). In our work, we have identified the presence of trans-piceid in peanut butter with a new method to quantify trans-resveratrol and trans-piceid (3-beta-glucose of trans-resveratrol). This fact is very interesting because the glucosilated form could be more easily absorbed by the intestinal gut; in this way trans-piceid would exercise its beneficial function more efficiently than trans-resveratrol. To our knowledge, this is the first time that trans-piceid has been quantified in peanut butter. Resveratrol and piceid contents in natural peanut butters were found to be significantly higher than those in blended peanut butters. 相似文献
65.
Evaluation of an in-office allergy screening test in nonatopic dogs having various intestinal parasites 下载免费PDF全文
Paradis M Lécuyer M 《The Canadian veterinary journal. La revue veterinaire canadienne》1993,34(5):293-295
An in-office allergy screening kit was evaluated in 10 dogs that had no clinical signs of atopy but had various intestinal parasites. All 10 dogs had a positive reaction to the dust mite Dermatophagoïdes farinae, and four dogs had positive reactions to at least one other group of allergens. The kit as presently marketed gives numerous false positive results in parasitized nonatopic dogs. 相似文献
66.
We have studied the seasonal relationship between growth and circulating growth hormone (GH), hepatic GH-binding and plasma
insulin-like growth factor-I immunoreactivity in gilthead sea bream,Sparus aurata. The seasonal increase in plasma GH levels preceded by several weeks the summer increase in growth rates. In contrast, a
marked increase in hepatic GH-binding with a high degree of endogenous GH occupancy was found during the period of maximum
growth which suggests an enhanced sensitivity of liver to GH action. Thus, circulating levels of immunoreactive IGF-I, probably
derived from the liver in response to GH action, were positively correlated with growth throughout the experimental period
although a consistent relationship between growth and circulating GH was not found. In spite of this, we consider that, in
gilthead sea bream, as in several other teleosts, the availability of endogenous GH can limit growth. Thus, under environmental
conditions of suboptimal growth, a single intraperitoneal injection of recombinant rainbow trout GH (rtGH) induced over the
dose range tested (0.75, 1.5, 3 μg g BW−1) an increase in plasma IGF-I-like immunoreactivity comparable to that seen during the period of maximum growth. 相似文献
67.
Occurrence of naturally acetylated lignin units 总被引:2,自引:0,他引:2
Del Río JC Marques G Rencoret J Martínez AT Gutiérrez A 《Journal of agricultural and food chemistry》2007,55(14):5461-5468
This work examines the occurrence of native acetylated lignin in a large set of vascular plants, including both angiosperms and gymnosperms, by a modification of the so-called Derivatization Followed by Reductive Cleavage (DFRC) method. Acetylated lignin units were found in the milled wood lignins of all angiosperms selected for this study, including mono- and eudicotyledons, but were absent in the gymnosperms analyzed. In some plants (e.g., abaca, sisal, kenaf, or hornbeam), lignin acetylation occurred at a very high extent, exceeding 45% of the uncondensed (alkyl-aryl ether linked) syringyl lignin units. Acetylation was observed exclusively at the gamma-carbon of the lignin side chain and predominantly on syringyl units, although a predominance of acetylated guaiacyl over syringyl units was observed in some plants. In all cases, acetylation appears to occur at the monomer stage, and sinapyl and coniferyl acetates seem to behave as real lignin monomers participating in lignification. 相似文献
68.
Ousmane Diankha Aliou Ba Patrice Brehmer Timothée Brochier Bamol Ali Sow Modou Thiaw Amadou Thierno Gaye Fambaye Ngom Hervé Demarcq 《Fisheries Oceanography》2018,27(4):351-365
We investigate Sardinella aurita and Sardinella maderensis recruitment success relative to the variability of oceanographic conditions in Senegalese waters using generalized additive models (GAM). Results show that recruitment of both species is marked by a strong intra‐annual (seasonal) variation with minimum and maximum in winter and summer, respectively. Their interannual variations are synchronous until 2006 (recruitment decreasing), while from 2007 there is no synchrony. The model developed shows that sardinella recruitment variability is closely related to the tested environmental variables in the study area. However, the key environmental variables influencing the recruitment success are different for both species: the Coastal Upwelling Index and the sea surface temperature for S. aurita and S. maderensis, respectively. We report that recruitment success of S. aurita and S. maderensis are associated with distinct ranges of sea surface temperature, upwelling intensity, wind‐induced turbulence, concentration of chlorophyll‐a and north Atlantic oscillation index. Considering food security and socio‐economic importance of both stocks, we recommend that consideration is given to the environmental variability in the small pelagic fish national management plans, particularly in the context of climate change. 相似文献
69.
The sialyl transferase of disialoganglioside formation is depressed in mammary tumors induced in the rat by 7,12-dimethylbenz[a]anthracene. Specific activities of other glycosyltransferases of the pathway ceramide to monosialo-ganglioside are unchanged or elevated so that the ganglioside GM(1) accumulates and higher gangliosides are depressed. These findings with a solid tumor are critical to an involvement of gangliosides in the cell-surface changes of tumorigenesis. 相似文献
70.
Treatment of canine parvoviral enteritis with interferon-omega in a placebo-controlled challenge trial 总被引:3,自引:0,他引:3
Martin V Najbar W Gueguen S Grousson D Eun HM Lebreux B Aubert A 《Veterinary microbiology》2002,89(2-3):115-127
Canine parvoviral enteritis continues to cause significant morbidity and mortality in dogs worldwide, and efficacious antiviral therapies are lacking. The present trial was aimed at evaluating the therapeutic efficacy of a recombinant feline interferon (type omega) preparation in the treatment of parvoviral enteritis in dogs. A double-blind, placebo-controlled challenge trial was performed in beagle pups (8-9 weeks); clinical signs, body weight, hematologic parameters, and mortality were monitored for a period of 14 days after challenge. Fourteen animals were inoculated with virulent canine parvovirus; 10 animals that developed clinical signs thereby meeting the inclusion criteria were admitted to the treatment phase in two randomly selected groups (placebo and IFN) of equal size. The IFN group received daily intravenous injections of rFeIFN-omega (2.5 MU/kg) for three consecutive days. The placebo group received daily injections of saline without IFN. Both groups of animals received individual supportive treatment consisting of adjusted diet and electrolyte solution.All five dogs in the placebo group developed fulminating enteritis with typical clinical signs and died within 10 days post-inoculation (or 6 days post-treatment). In the IFN-treated group, one animal died on day 2 after the treatment was started, whereas the other four dogs survived the challenge and gradually recovered. Our data confirm that the rFeIFN-omega can exert a significant therapeutic effect on dogs with parvoviral enteritis by improving clinical signs and reducing mortality. 相似文献