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101.
Vallejo F Gil-Izquierdo A Pérez-Vicente A García-Viguera C 《Journal of agricultural and food chemistry》2004,52(1):135-138
Broccoli (Brassica oleracea L. var. italica cv. Marathon) inflorescences are a good source of bioactive compounds, such as phenolics (flavonoids and hydroxycinnamoyl derivatives), glucosinolates, and vitamin C. In this work, these health-promoting compounds were submitted to digestion under in vitro gastrointestinal conditions (pH, temperature, enzyme, and chemical conditions). This technique differentiated among the compounds associated with macromolecules in soluble and insoluble form and those that are freely soluble. In addition, it evaluates the chemical stability of the broccoli compounds under simulated physiological conditions. The gastric digestion of broccoli caused high losses in glucosinolates (69% loss), whereas phenolics and vitamin C presented higher stability under these conditions. Thus, there were no losses in flavonoids, a 7% loss of vitamin C, and a variable rate of loss (6-25%) in hydroxycinnamic acid derivatives. The stability of all of the compounds was affected by the in vitro intestinal conditions. Under the in vitro conditions, flavonoids and hydroxycinnamoyl acid derivatives were of low availability, due to their significant losses under these conditions, at the end of the experiment (84 and 80% loss, respectively). Vitamin C was the metabolite that showed the greater decrease after intestinal digestion (91% loss). Regarding the remaining glucosinolates, these compounds presented higher stability under intestinal conditions, rendering an availability similar to that found for phenolics (75% loss). Therefore, broccoli components were affected by gastric and/or intestinal conditions depending on the type of compound. Thus, glucosinolates were mainly degraded by gastric conditions, whereas phenolic compounds and vitamin C were degraded by intestinal conditions. 相似文献
102.
Recio E Alvarez-Rodríguez ML Rumbero A Garzón E Coque JJ 《Journal of agricultural and food chemistry》2011,59(23):12589-12597
A chemical method for the efficient destruction of 2,4,6-trichloroanisole (TCA) and pentachloroanisole (PCA) in aqueous solutions by using hydrogen peroxide as an oxidant catalyzed by molybdate ions in alkaline conditions was developed. Under optimal conditions, more than 80.0% TCA and 75.8% PCA were degraded within the first 60 min of reaction. Chloroanisoles destruction was followed by a concomitant release of up to 2.9 chloride ions per TCA molecule and 4.6 chloride ions per PCA molecule, indicating an almost complete dehalogenation of chloroanisoles. This method was modified to be adapted to chloroanisoles removal from the surface of cork materials including natural cork stoppers (86.0% decrease in releasable TCA content), agglomerated corks (78.2%), and granulated cork (51.3%). This method has proved to be efficient and inexpensive with practical application in the cork industry to lower TCA levels in cork materials. 相似文献
103.
L. A. Gracia Calvo M. Martín‐Cuervo E. Peña J. Fruto J. Jiménez L. J. Ezquerra 《Equine Veterinary Education》2011,23(7):346-352
A foal with a cranio‐dorsal coxofemoral luxation was treated with a prosthetic capsulorraphy technique after open reduction. After reluxation a femoral head ostectomy was performed for salvage purposes. The filly was discharged with minimal lameness and was using the limb properly after 51 days of hospitalisation. Four years later the filly is still doing well as a breeding mare, with an acceptable quality of life despite angular deformities in the contralateral limb. 相似文献
104.
Feather follicle movement control was studied on feathers of the pectoral tract in the anaesthetized chicken. Dissection of nerves leading to the follicles showed that their origin was at least partially in the sympathetic ganglia. Reflectoric ruffling of feathers could be obtained after adequate stimulation. Intravenous injections of drugs in doses which influenced the circulation gave the following results: Adrenaline caused erection of feathers which was abolished by phentolamine. Noradrenaline caused up and down movements after injection only at high doses. Similar results were obtained by placing of skin pieces in saline containing the drugs. The reaction to drugs was typical always for a given group of feathers. Killing of birds and anaesthesia caused general erection of feathers which was not abolished by phentolamine. The findings suggest that adrenergic synapses are involved in feather follicle movement control, but at least another mechanism (CNS) regulates feather follicle movement. 相似文献
105.
Recent changes in landscape structure and function in a mediterranean region of SW Spain (1950–1984)
Recent economic development has altered landscape structure and function of a mediterranean region in Southwestern Spain.
Intensive agricultural systems have concentrated in the more fertile areas, while marginal ones have been abandoned. As a
result, landscape structure has changed. Consequences of this structural change on landscape processes are discussed. 相似文献
106.
107.
Shih C Museth AK Abrahamsson M Blanco-Rodriguez AM Di Bilio AJ Sudhamsu J Crane BR Ronayne KL Towrie M Vlcek A Richards JH Winkler JR Gray HB 《Science (New York, N.Y.)》2008,320(5884):1760-1762
Energy flow in biological structures often requires submillisecond charge transport over long molecular distances. Kinetics modeling suggests that charge-transfer rates can be greatly enhanced by multistep electron tunneling in which redox-active amino acid side chains act as intermediate donors or acceptors. We report transient optical and infrared spectroscopic experiments that quantify the extent to which an intervening tryptophan residue can facilitate electron transfer between distant metal redox centers in a mutant Pseudomonas aeruginosa azurin. Cu(I) oxidation by a photoexcited Re(I)-diimine at position 124 on a histidine(124)-glycine(123)-tryptophan(122)-methionine(121) beta strand occurs in a few nanoseconds, fully two orders of magnitude faster than documented for single-step electron tunneling at a 19 angstrom donor-acceptor distance. 相似文献
108.
Balanyà et al. (Reports, 22 September 2006, p. 1773) build on earlier claims that chromosomal inversion polymorphisms of Drosophila subobscura are rapidly evolving in response to global warming. However, that conclusion is not adequately buttressed by their data, because they overlooked the lag between calendar and climatological dates created by the progressive lengthening of the growing season in their sampling approach. 相似文献
109.
Angel?I.?Ortiz-Ceballos Carlos?FragosoEmail author 《Biology and Fertility of Soils》2004,39(6):438-445
Earthworm populations were studied in three tropical agroecosystems of southern Mexico: improved maize with a Mucuna pruriens cover crop (MM), continuous conventional maize (CM) and pastures (P). Three replicates and six monoliths were sampled in each agroecosystem. Three earthworm species were found, two native (Balanteodrilus pearsei, Larsonidrilus orbiculatus) and one exotic (Polypheretima elongata). In all systems, the dominant species was B. pearsei, with negligible presence of the exotic species in MM and P plots. Total abundance was significantly higher in MM than in CM; and earthworm biomass was also higher in MM than in CM and P. Juveniles of both native species dominated, mainly concentrated in the top 20 cm of soil. B. pearsei and L. orbiculatus displayed different preferences (within each agroecosystem) for soil organic matter, N and temperature. Further experiments are required to investigate whether mulching with M. pruriens results in an increased earthworm abundance and biomass through a N-improvement effect or as a result of microclimatic changes and to study the extent to which earthworms and M. pruriens are synergistic in enhancing maize growth. 相似文献
110.
The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in the tropics. Monitored three batches of approximately 18,000 females each (one for each genetic type), from weeks 24 to 64, according to the conditions of handling and power described by the generic lines distribution companies. Although no differences were found for feed intake, Cobb Avian was presented a lower rate of feed conversion, being also that presented the highest percentage of implementation and production of incubables eggs, which meant that it was in line with the highest cumulative production of chickens by bird and week for tropical conditions studied. To adjust the lay data to a Gorssman model, in order to predict the parameters that characterize the lay modeling, estimated the best behavior for Cobb Avian 48 females, because while it takes more time to reach the level of putting constant (5.30 weeks) and maintain it for less time (2.4 weeks), they manage to put constant high (79.11%) level, considering that the largest number of eggs per bird (171.19 vs. 164.54 and 160.11 in Arbor Acres and Ross 208, respectively). 相似文献