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51.
Aurelia Bonet Nieves Diaz-Caneja Isabel Gutierrez Antonio Martínez Eugenio Villar 《Water, air, and soil pollution》1988,38(1-2):181-188
A study was carried out on the pH values obtained from bulk (wet and dry) precipitation samples collected simultaneously in two cities in Cantabria (Spain), Santander and Torrelavega over a period of a year. It was observed that the annual weighted average values for the pH of precipitation, 4.42 and 4.21, respectively, differ significantly although the difference is less than that existing between their pollution levels. The difference is greater when total annual H+ depositions are compared. The study also demonstrated the strong influence of long-range transport effect on acidity and to a lesser degree the effect of mid-range transport. 相似文献
52.
Gallardo-Guerrero L Hornero-Méndez D Mínguez-Mosquera MI 《Journal of agricultural and food chemistry》2002,50(23):6746-6751
The pectic and pigment compositions and Ca and Cu contents of the alcohol-insoluble solid (AIS) residues were determined in cv. Gordal olives treated with NaOH solution and kept at different constant pH values (3.5-6.5). The same controls were made in table olives presenting green staining alteration. The ratio between the various pectin fractions of the more acid pH experiment samples remained similar in fruits not showing green staining. In altered fruits, the protopectin fraction was lower, and the calcium pectate or EDTA soluble pectins were higher. Regarding the presence of Ca and Cu in the AIS, it was observed that, whereas Ca levels fell at the most acid pH values, those of Cu increased. The concentration of Ca was higher in the AIS of altered olives than in nonaltered ones. The same trend was seen for the zone with or without green staining of an altered fruit. In the case of Cu, the relationship was the opposite: a decrease in the levels of AIS Cu in fruits and zones of fruits with green staining. This result was correlated with the highest concentration of Cu-chlorophyll complexes found in such samples and suggested that pectins might act as a reservoir of Cu involved in the alteration. 相似文献
53.
Luis Miguel Brito Áurea Sampaio Rui Pinto Isabel Mourão João Coutinho 《Journal of plant nutrition》2016,39(6):842-849
The response of lettuce to production system, organic and phosphate fertilizers and root mycorrhization, was evaluated in two pot trials with factorial treatment combination of: (i) soil type (from organic and from conventional production systems) and organic fertilizer (0, 2 and 4 t ha?1) in the first trial; and (ii) mycorrhizal inoculation (mycorrhized and non-mycorrhized plants) and Gafsa phosphate (0, 100 and 200 kg P2O5 ha?1) in the second. Lettuce growth decreased with increasing rates of the organic fertilizer because of its very high electrical conductivity (50.1 dS m?1) and lack of maturation. However, the fertilizer harmful effects were minimized in the soil from organic production. The application of Gafsa phosphate significantly increased lettuce yield and nutrient uptake. However, for the highest rate of phosphate, mycorrhized lettuce yield decreased compared to non-mycorrhized lettuce, suggesting that high soil available P may have harmful effects on the activity of mycorrhizal fungi. 相似文献
54.
Ould El Kebir MV Barnathan G Siau Y Miralles J Gaydou EM 《Journal of agricultural and food chemistry》2003,51(7):1942-1947
If a great number of rays are fished in the Tropical East Atlantic Ocean for their caudal fins, only a small amount of ray flesh is processed. Among them, three species of rays, Dasyatis marmorata, Rhinobatos cemiculus, and Rhinoptera marginata, from the Mauritanian coast have been investigated for the fatty acid composition of their lipids. Gas chromatography and gas chromatography-mass spectrometry allowed identification of 50 molecules from muscles, livers, and gonads of these fishes. Principal component analysis, starting from >50 samples, reveals significant differences in various fatty acid distributions, related to the species and sex of the sampled fish. Some of them are preferentially present in one sex or in both species, whereas the occurrence of others characterizes the male and female of one or two species. The results show that rays are potential resources of polyunsaturated fatty acids (PUFA) and should be used in the diet of local populations. The lipidic fractions contained a high amount of PUFA (up to 30% of the total), mainly composed of docosa-4,7,10,13,16,19-hexaenoic acid, eicosa-5,8,11,14-tetraenoic acid, and eicosa-5,8,11,14,17-pentaenoic acid. 相似文献
55.
The effect of arginine vasopressin on the stimulation of prostaglandin F2 alpha (PGF2 alpha) release has been examined in vivo. Fifty-eight heifers received one intravenous injection of 10 IU arginine vasopressin on either Day 0 (n = 14), Day 6 (n = 12), Day 13 (n = 14) and Day 18 or 19 or 20 (Day 18-20, n = 18) after the onset of oestrus (Day 0) to determine the effect of arginine vasopressin at different times of the oestrous cycle. Frequent blood samples were taken before and after arginine vasopressin injection for the measurement of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) by radioimmunoassay (RIA). Blood samples for progesterone determinations were taken 2 hr before and 24 hr after arginine vasopressin to monitor luteal function. The data show that arginine vasopressin causes an increase (P less than 0.005) in PGFM concentrations only at Day 18-20 of the cycle in 67% of the experimental heifers. 相似文献
56.
María Delclaux Covadonga Talavera Manuel López Jose Miguel Sánchez María Isabel García 《Journal of zoo and wildlife medicine》2002,33(3):283-285
A 17-mo-old captive-born female red panda (Ailurus fulgens fulgens) presented with a sudden onset of lameness in its left hind leg was diagnosed radiographically as having possible severe, bilateral Legg-Calve-Perthes disease with fracture of the great trochanter of the left femur. Surgical repair of the fracture was performed using pins and a tension band wire through a lateral approach to the hip. This is the first case reported at Madrid Zoo-Aquarium, where 63 individuals have been bred over 15 yr. 相似文献
57.
Ehrlichia ruminantium is the causative agent of Heartwater, a fatal tick-borne disease affecting ruminants in African countries and West Indies and can be used as an inactivated vaccine for wild and domestic animals. In order to improve E. ruminantium production yields we characterize E. ruminantium growth kinetics in terms of duplication time, maximum production yield, and peak of infectivity. After a 24 h period for E. ruminantium attachment/internalization and a lag phase of 12 h, the exponential growth occurred within 36-108 h post-infection (hpi) with a net increase of up to 2.2 orders of magnitude. Maximum E. ruminantium infectivity was observed at 120 hpi and was defined as the best time of harvesting (TOH) for propagation of E. ruminantium cultures. This study showed that considering the quality constraint of the final product (E. ruminantium vaccine), the E. ruminantium suspension should be harvested at 113 hpi. Overall, the characterization of E. ruminantium progression through the average infection cycle, not only can contribute to the maximization of E. ruminantium production yield, with important consequences for the large scale production and utilization of an inactivated Heartwater vaccine, but also to elucidate growth mechanisms of some of the other ehrlichial species, with emerging impact in human and animal health. 相似文献
58.
59.
Anaplasma infection in free-ranging Iberian red deer in the region of Castilla-La Mancha, Spain 总被引:4,自引:0,他引:4
De La Fuente J Vicente J Höfle U Ruiz-Fons F Fernández De Mera IG Van Den Bussche RA Kocan KM Gortazar C 《Veterinary microbiology》2004,100(3-4):163-173
Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, Anaplasma marginale, causes bovine anaplasmosis and infects erythrocytes of the vertebrate host and undergoes a complex developmental cycle in ticks which serve as biological vectors. Infected cattle, wild ruminants and ticks can all serve as reservoirs of A. marginale. In this study, hunter killed Iberian red deer (Cervus elaphus hispanicus) from the region of Castilla-La Mancha in southwestern Spain were tested for Anaplasma infection. We found that 10% of the deer examined were seropositive for Anaplasma. Three A. marginale strains were subsequently obtained from salivary glands of Hyalomma marginatum that were removed from these deer, and the sequence of the major surface protein (msp)4 gene was determined for each strain and used for phylogenetic studies. Maximum parsimony analyses of msp4 sequences from H. marginatum ticks in comparison with New World cattle and bison isolates reported previously, suggested different origins for these Spanish A. marginale strains. The results of this study demonstrated that Iberian red deer are naturally infected with Anaplasma, and may therefore serve as a wildlife reservoir of the pathogen. Although the link between deer infection and the strains of A. marginale identified in ticks was not established, H. marginatum and Rhipicephalus bursa were identified as potential biological vectors for A. marginale in this region and may effect transmission of A. marginale between deer and cattle populations. 相似文献
60.
Gutiérrez A Rodríguez IM del Río JC 《Journal of agricultural and food chemistry》2006,54(6):2138-2144
The chemical composition of lignin and lipids of bast fibers from industrial hemp (Cannabis sativa) used for high-quality paper pulp production was studied. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) of fibers showed a lignin with a p-hydroxyphenyl:guaiacyl:syringyl unit (H:G:S) molar proportion of 13:53:34 (S/G ratio of 0.64). p-Hydroxycinnamic acids, namely, p-coumaric and ferulic acids, were found in only trace amounts. Among the lipids, the main compounds identified by GC/MS of the hemp fibers extracts were series of n-alkanes, free and esterified sterols and triterpenols, waxes, and long-chain n-fatty acids. Other compounds such as n-aldehydes, n-fatty alcohols, steroid hydrocarbons, and steroid and triterpenoid ketones as well as steryl glycosides were also found. 相似文献