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61.
The metabolism of benodanil (2-iodobenzanilide) was studied in rats following an oral dose of 150 mg benodanil kg?1 body weight. The major 24-h urinary metabolite was found to be the 4′-hydroxy derivative, both free (≈ 5%) and as the glucuronide (≈ 4%) and sulphate (≈ 4%) conjugates. Over a 6-day period, about 16% of the administered dose was excreted in the urine and about 80% in the faeces. After dosing with [14C]- benodanil, blood radioactivity levels were highest 30 min after dosing, with small broader peaks at 4 and 7 h, while biliary activity levels rose slowly to a maximum about 10–12 h after the dose, some 16% being excreted in 24 h as the glucuronide conjugate of the 4′-hydroxy derivative. 相似文献
62.
The major soluble metabolite of carboxin (2,3-dihydro-6-methyl-5-phenylcarbamoyi-1,4-oxathiin) in barley seedlings and mature plants was identified as the-hydroxy phenyl derivative. This phenol was also bound to the lignin fraction. The distribution of carboxin and its metabolites in seedlings and mature plants grown from treated seed was studied; maximum residues were found in the three oldest internodes, with traces in the roots and flowering heads. Treated plants had altered chlorophyll/carotenoid ratios, and raised levels of some free amino acids. 相似文献
63.
Dias EC Pereira RG Borém FM Mendes E de Lima RR Fernandes JO Casal S 《Journal of agricultural and food chemistry》2012,60(16):4120-4125
Immature coffee fruit processing contributes to a high amount of defective beans, which determines a significant amount of low-quality coffee sold in the Brazilian internal market. Unripe bean processing was tested, taking the levels of bioactive amines as criteria for evaluating the extent of fermentation and establishing the differences between processing methods. The beans were processed by the dry method after being mechanically depulped immediately after harvest or after a 12 h resting period in a dry pile or immersed in water. Seven bioactive amines were quantified: putrescine, spermine, spermidine, serotonin, cadaverine, histamine, and tyramine, with global amounts ranging from 71.8 to 80.3 mg/kg. The levels of spermine and spermidine were lower in the unripe depulped coffee than in the natural coffee. The specific conditions of dry and wet processing also influenced cadaverine levels, and histamine was reduced in unripe depulped coffee. A resting period of 12 h does not induce significant alteration on the beans and can be improved if performed in water. These results confirm that peeling immature coffee can decrease fermentation processes while providing more uniform drying, thus reducing the number of defects and potentially increasing beverage quality. 相似文献
64.
R D Wesley R D Woods J D McKean M K Senn Y Elazhary 《Canadian journal of veterinary research》1997,61(4):305-308
Three hundred and forty-seven serum samples from 22 Iowa swine herds were screened for TGEV/PRCV neutralizing antibody. Ninety-one percent of the sera and all 22 herds were positive. These sera were then tested by the blocking ELISA test to distinguish TGEV and PRCV antibody. The ELISA test confirmed the high percentage of TGEV/PRCV positive sera. By the blocking ELISA test, 12 herds were PRCV positive, 6 herds were TGEV positive and 4 herds were mixed with sera either positive for TGEV or PRCV antibody. The results suggest a recent increase in TGEV/PRCV seroprevalence in Iowa swine most likely due to subclinical PRCV infections. 相似文献
65.
Seven populations collected at different altitudes in northern Italy, two Ladino breeding populations and two control cultivars
(AberHerald and Grasslands Huia) of white clover (Trifolium repens L.) were included in a series of experiments analysing: (i) levels of cold tolerance using artificial and field-based methods;
(ii) relationships between these measures of cold tolerance; (iii) components of spring yield, various physiological traits,
and their relationships with cold tolerance. Rates of seedling and growing point mortality in the populations over winter,
assessed in separate field experiments, were closely related (r = 0.85). Grasslands Huia showed the highest death rates, and material originating from high altitudes the lowest. The LT50 value, i.e., the temperature at which 50% of the growing points would die, estimated by an artificial freezing test, was
significantly correlated with field-based measures of seedling (r = 0.64) and growing point (r = 0.84) mortality. The existence of these correlations is of potential interest for the development of indirect selection
criteria for complex and expensive-to-evaluate traits such as winter survival in field plots. Besides being reliable, in this
study the artificial assessment was also sensitive, providing a greater degree of separation of the populations means than
field-based measures. Of the several physiological traits (water content,concentrations of water soluble and total non-structural
carbohydrate, and water soluble protein content of stolons) measured at a mid-winter sampling date under field conditions,
the only character showing significant variation between populations was soluble protein content. There was a slight trend
for material with a higher protein content to exhibit greater field-based values of cold tolerance. High altitude populations
tended to have low spring yields. The highest spring yield was found in one of the Ladino populations. The study identified
two populations which combined, to differing extents, cold tolerance and spring yield characteristics that would be of potential
use in breeding for specified agronomic/climatic zones.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
66.
67.
C. Xiao R. Stevens M. Fauci R. Bolton M. Lewis W. T. McKean D. F. Bezdicek W. L. Pan 《Biology and Fertility of Soils》2007,43(6):709-719
The cereal and grass seed cropping systems of the Pacific northwestern USA generate a valuable fiber source for papermaking.
Pulping straw with KOH produces black liquor, an organic waste effluent with potential as a K source and soil amendment. The
objectives of this study were to determine if black liquor from wheat straw pulping with KOH improves soil quality including
soil aggregation, microbial biomass and microbial activity, and corn yield. A 2-year field trial with a randomized complete
block design was conducted with black liquor or KCl applied at 168 and 336 kg K ha−1 at two sites, respectively, planted to corn in Central Washington. Black liquor applied at rates of 168 and 336 kg K ha−1 slightly increased soil pH by 0.2 to 1.4 units and electrical conductivity by 0.0 to 0.8 dS m−1 at both sites, and significantly increased soil test K compared to the nonamended control by 199 to 368 mg K kg−1 soil in the top 5 cm at Paterson and by 44 to 200 mg K kg−1 soil in the top 5 cm at Prosser. Corn had no yield response to the application of either K sources, black liquor, or KCl
applied at both rates at both sites. Generally, black liquor applied at these rates increased soil dehydrogenase, β-glucosidase,
and arylsulfatase activities, microbial biomass C, and soil wet stable macroaggregates in the top 5-cm soil at both sites.
The results of this study suggest that the organic-rich waste liquor from wheat straw pulping with KOH may improve soil quality
and soil test K without reducing crop productivity. 相似文献
68.
Li R Schmidt W Rankin S Walzem RL Boyle-Roden E 《Journal of agricultural and food chemistry》2003,51(2):477-482
The amount of acyl heterogeneous triacylglycerol (TG(HET)) solubilized by phosphatidylcholine (PC) vesicles, prepared by co-sonication of egg PC and small amounts (<6% w/w) of TG(HET), was determined using (13)C nuclear magnetic resonance (NMR). The acyl chains of TG(HET) were predominantly 16 or 18 carbons in length, 50% saturated, and approximately 21.7% (13)C isotopically enriched at the carbonyl carbon. The (13)C NMR spectra revealed two carbonyl resonances at chemical shift values between PC carbonyls and oil-phase TG carbonyls, confirming the presence of TG(HET) solubilized in PC vesicles. Oil-phase TG carbonyl peaks were present only in spectra of vesicles containing >3 wt % TG(HET). Integration of TG(HET) carbonyl resonances determined that PC vesicles solubilized 3.8 wt % of TG(HET), compared to 2.8 wt % of acyl homogeneous triolein. The difference between the maximum solubility of TG(HET) and that of homogeneous TG (TG(HOM)) with similar acyl chain lengths provides evidence that specific acyl composition, in addition to the acyl chain length of triacylglycerols, affects the solubility of TG in PC vesicles and TG-rich lipoprotein surfaces. Thus, TG(HET) may innately be a better model substrate than TG(HOM) for determination of substrate availability of TG at lipoprotein surfaces. 相似文献
69.
G. Barry Baker Michael C. Double Rosemary Gales Cathryn L. Abbott Samantha L. Petersen Rachael Alderman 《Biological conservation》2007,137(3):319-333
Hundreds of thousands of seabirds are killed each year as a result of interacting with longline and trawl fishing operations, and the severity of the impact varies regionally. Shy and white-capped albatrosses, Thalassarche cauta and Thalassarche steadi respectively, are phenotypically similar species known to be incidentally killed by fishing operations. The magnitude of this mortality has not previously been assessed across their range. Here we examine recent effort and bycatch rates in fisheries known to incidentally kill these species and qualitatively evaluate the level of impact of each fishery. Results indicate that over 8500 of these albatrosses may be killed annually, although the reliability of this estimate is low due to the paucity of comprehensive observer data in most fisheries. Of the estimated deaths of all seabird species in the fisheries assessed, trawl and longline fisheries killed birds in approximately equal proportions, but when the mortality levels of shy-type albatrosses were examined, trawl fisheries were responsible for 75% of all deaths. Data suggest most of these birds were killed in South African, Namibian and New Zealand demersal trawl fisheries and the South Africa pelagic longline fishery. Because most adult shy albatrosses are comparatively sedentary and rarely found outside Australian waters, it is primarily juvenile shy albatrosses that regularly encounter fishing fleets known to kill large numbers of albatrosses. In contrast, throughout most of their range juvenile and adult white-capped albatrosses are exposed to fisheries that collectively kill many thousands of these albatrosses each year. These data emphasise the urgent need for robust assessments of the impact of bycatch at a species and population level, and the urgent implementation of effective mitigation measures. 相似文献
70.