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排序方式: 共有882条查询结果,搜索用时 15 毫秒
91.
Commercial red wines ( Vitis vinifera L. cv. Shiraz) produced during the 2009 vintage underwent winemaker assessment for allocation grade soon after production. The wines were then subjected to phenolic analysis to measure wine color (total anthocyanin, SO(2) nonbleachable pigment, and wine color density) and tannins (concentration, composition, and average degree of polymerization). A positive relationship was found between wine phenolic concentration and projected bottle price. Tannin compositional analysis suggested that there was specifically a relationship between wine grade and skin-derived tannins. These results suggest that maximization of skin tannin concentration and/or proportion is related to an increase in projected wine bottle price. 相似文献
92.
Dynamic plant uptake model applied for drip irrigation of an insecticide to pepper fruit plants 总被引:1,自引:0,他引:1
BACKGROUND: Drip application of insecticides is an effective way to deliver the chemical to the plant that avoids off‐site movement via spray drift and minimizes applicator exposure. The aim of this paper is to present a cascade model for the uptake of pesticide into plants following drip irrigation, its application for a soil‐applied insecticide and a sensitivity analysis of the model parameters. RESULTS: The model predicted the measured increase and decline of residues following two soil applications of an insecticide to peppers, with an absolute error between model and measurement ranging from 0.002 to 0.034 mg kg fw?1. Maximum measured concentrations in pepper fruit were approximately 0.22 mg kg fw?1. Temperature was the most sensitive component for predicting the peak and final concentration in pepper fruit, through its influence on soil and plant degradation rates. CONCLUSION: Repeated simulations of pulse inputs with the cascade model adequately describe soil pesticide applications to an actual cropped system and reasonably mimic it. The model has the potential to be used for the optimization of practical features, such as application rates and waiting times between applications and before harvest, through the integrated accounting of soil, plant and environmental influences. Copyright © 2011 Society of Chemical Industry 相似文献
93.
Analysis of proanthocyanidin cleavage products following acid-catalysis in the presence of excess phloroglucinol 总被引:12,自引:0,他引:12
The analysis of proanthocyanidin cleavage products after acid-catalysis in the presence of excess phloroglucinol was investigated. In the developed analytical method, a solution of 0.1 N HCl in methanol, containing 50 g/L phloroglucinol and 10 g/L ascorbic acid was prepared. The proanthocyanidin of interest was reacted in this solution (5 g/L) at 50 degrees C for 20 min, and afterward combined with 5 volumes of 40 mM aqueous sodium acetate before analysis by reversed-phase HPLC using an aqueous acetic acid and methanol gradient. This procedure was used to investigate the composition of proanthocyanidins isolated from the seed and skin tissue of Vitis vinifera L. berries. The results compared favorably to results obtained when benzyl mercaptan was used as the trapping nucleophile, indicating that phloroglucinol is an effective reagent for this analysis. 相似文献
94.
95.
Fifteen cows among a herd of 50 suckler cows and calves rapidly lost body condition and became dull and anorexic after grazing pasture containing bog asphodel (Narthecium ossifragum) during the summer of 1989. The affected cows had evidence of kidney damage characterised by elevated plasma urea and creatinine concentrations. Eleven cows died and diffuse renal tubular necrosis was present in three cows which were examined post mortem. Similar renal lesions were reproduced experimentally by feeding bog asphodel to a healthy calf. 相似文献
96.
J L Burton B W McBride B W Kennedy J H Burton T H Elsasser B Woodward 《Journal of animal science》1992,70(5):1488-1495
Recombinant bovine somatotropin (bST) was administered at 0, 10.3, or 20.6 mg per cow per day to 32 Holsteins for 38 wk. Fifteen currently treated cows had been treated in the previous lactation. Eighteen hematological variables and blood concentration of insulin-like growth factor I (IGF-I) were measured at five sample periods. The objectives of the study were to test the effects of bST treatments on hematological profiles and to relate blood IGF-I concentration to these variables. Results indicated little influence (P greater than .10) of previous bST treatments on hematological profiles measured in the current lactation. Current bST treatments, however, altered hematocrits (P = .10), mean corpuscular volume (P = .03), mean corpuscular hemoglobin (P = .009), and fraction of blood lymphocytes (P = .09). A week x bST treatment interaction also contributed to variation in hematocrit (P = .09), mean corpuscular hemoglobin (P = .05), fraction of neutrophils (P = .02), and fraction of lymphocytes (P = .04). Blood IGF-I concentration influenced fractions and counts of neutrophils (P = .06, .09), lymphocytes (P = .04, .02), and monocytes (P = .08, .05). Further in vivo and in vitro studies are warranted because this preliminary evidence suggests that bST and(or) IGF-I contribute to regulation of hematopoiesis in mature dairy cows. 相似文献
97.
Ian R. Dohoo S.Wayne Martin Ian McMillan Brian W. Kennedy 《Preventive veterinary medicine》1984,2(5):655-670
Effects of age, season and sire on the occurrence of common diseases of Holstein-Friesian cows were evaluated in a two and a half year study. The data were from 2875 lactation records from 2008 cows in 32 commercial dairy herds within a 50 mile radius of Guelph, Ontario.Age patterns for all disease conditions were determined using χ2 or quadratic regression analyses. Linear increases with age were observed for milk fever, mastitis requiring local therapy only, cystic ovaries and foot and leg problems. Quadratic relationships with age were observed for ketosis (clinical and subclinical), mastitis requiring systemic therapy, subclinical mastitis, dystocia, respiratory diseases and traumatic reticulo-peritonitis. No consistent age patterns were found for retained placentas, reproductive tract infections, abomasal displacements, teat injuries, digestive disorders and abortions.Seasonal patterns were evaluated using a formal statistical test for the seasonality of events. Significant peaks were found in the risk of ketosis and cystic ovaries during the winter, and in the risk of teat injuries in the late winter or early spring. Seasonal patterns, more complex than a simple unimodal pattern, were observed for mastitis requiring local therapy only, traumatic reticulo-peritonitis and abortions.Heritabilities were determined for 9 disease conditions. All heritabilities were low or 0 with the exception of clinical ketosis (h2 = 0.31). 相似文献
98.
A double blind controlled trial was carried out on four commercial dairy herds, to investigate the effect of one 50 mg injection of selenium, 10 days before parturition, on the incidence of weak calves. Although the treatment marginally increased the selenium status of treated calves it did not decrease the incidence of the weak calf syndrome. 相似文献
99.
B L Roeder M M Chengappa T G Nagaraja T B Avery G A Kennedy 《Journal of the American Veterinary Medical Association》1987,190(12):1550-1555
Eight neonatal calves (2 to 21 days old) with suspected abomasal displacement or intestinal obstruction after acute onset of abdominal tympany, colic, depression, or death were referred to Kansas State University for clinical examination or for necropsy. Results of routine hematologic and serum chemical analyses did not reveal consistent changes. Necropsy revealed abomasal distention, with various degrees of abomasitis, hemorrhage, and ulceration, but did not reveal evidence of displaced abomasum or obstructed intestine. Specimens of ruminal contents collected via stomach tube or at necropsy and abomasal contents collected at necropsy were obtained for anaerobic bacteriologic culture. Clostridium perfringens was isolated from all specimens, and on the basis of toxin neutralization tests in mice, 7 were type A and one was type E. Copper concentrations in serum and tissues were within normal limits. It appeared that the acute abdominal syndrome in these neonatal calves was unrelated to copper deficiency, and that C perfringens, particularly type A, may have had an appreciable contributory role in its pathogenesis. 相似文献
100.