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221.
222.
Rice endosperm protein was prepared by alkali-extraction method and subsequently modified by controlled glycosylation (RPGlu, RPXG), deamidation (RPDA), and enzymatic hydrolysis by alcalase (RPAlc) methods. The RPGlu and RPXG were prepared by Maillard type glycosylation with D-glucose and xanthan gum, respectively. The glycosylation improved the emulsion activity (0.721) and stability (26.8 min) of the protein but did not show a substantial improvement in solubility (39.7%). The rice protein modified by controlled alkali-deamidation (RPDA) showed highest solubility (68%), emulsion activity (0.776), and emulsion stability (24 min) among the three protein modification methods evaluated in this study. The alcalase treatment to 1.8% DH (RPAlc) slightly improved solubility (33%), emulsion activity (0.468), and emulsion stability (17.5 min) compared with unmodified rice protein (RP), which had 18% solubility, 0.266 emulsion activity, and 14.7 min emulsion stability. The glycosylation and deamidation methods were more effective than the controlled enzymatic hydrolysis by alcalase in improving solubility and emulsifying properties of rice endosperm protein. Glycosylated and deamidated rice endosperm proteins can find application in enhancing emulsifying properties in suitable products. 相似文献
223.
ÁE Domínguez‐Rebolledo F Martínez‐Pastor MR Fernández‐Santos E Del Olmo A Bisbal JL Ros‐Santaella JJ Garde 《Reproduction in domestic animals》2010,45(6):e360-e368
Several methods are used to measure lipid peroxidation (LPO) in spermatozoa. The objective of this study was comparing the thiobarbituric acid reactive species (TBARS) method and the BODIPY 581/591 C11 (B581) and BODIPY 665/676 C11 (B665) fluorescent probes to measure induced peroxidative damage in thawed epididymal spermatozoa from Iberian red deer. Samples from three males were thawed, pooled, diluted in PBS, incubated at room temperature and assessed at 0, 3, 6 and 24 h under different experimental conditions: Control, hydrogen peroxide (H2O2) 0.1 mm or 1 mm , or tert‐butyl hydroperoxide (TBH) 0.1 mm or 1 mm . LPO was assessed by the TBARS assay [malondialdehyde (MDA) detection] and by the fluorescence probes B581 and B665 (microplate fluorimeter and flow cytometry). Increasing MDA levels were only detectable at 1 mm of TBH or H2O2. Both fluorescence probes, measured with fluorometer, detected significant increases of LPO with time in all treatments, except Control. Flow cytometry allowed for higher sensitivity, with both probes showing a significant linear relationship of increasing LPO with time for all oxidizing treatments (p < 0.001). All methods showed a good agreement, except TBARS, and flow cytometry showed the highest repeatability. Our results show that both B581 and B665 might be used for LPO analysis in Iberian red deer epididymal spermatozoa, together with fluorometry or flow cytometry. Yet, the TBARS method offered comparatively limited sensitivity, and further research must determine the source of that limitation. 相似文献
224.
Schaefer VJ 《Science (New York, N.Y.)》1958,127(3308):1227-1229
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226.
The efficacy of chlorine dioxide (ClO2) as an alternative sanitizing agent for hatching eggs was investigated because of the health concerns about formaldehyde fumigation. Hatchability of chicken eggs was reduced when the eggs were dipped in the ClO2 solutions for more than 5 minutes or in concentrations greater than 100 ppm Cl. However, treating hatching eggs with a ClO2 foam or fumigating with formaldehyde had no adverse effect on hatchability compared with untreated control eggs. Sanitizing soiled duck eggs with ClO2 foam improved hatchability by more than 10% and hatch by more than 6% compared with untreated eggs (P less than 0.05). A novel method for assessing bactericidal potential of egg-sanitizing agents was developed. Using this technique, both chlorine dioxide foam and formaldehyde fumigation reduced the number of egg-contaminant bacteria inoculated on sterile chicken eggs compared with the number of bacteria on untreated eggs (P less than 0.05). These findings suggest that sanitizing hatching eggs with ClO2 foam may be a viable alternative to fumigating with formaldehyde. 相似文献
227.
The carabid fauna in three city parks of Kiel and in two beech woods in the surroundings was analysed by pitfall traps. 26 species (1667 individuals) were caught from April to August 1976. The carabids with high density in the city were euryecious, mainly of minor body size, mostly unable to fly and hibernated as larvae (probably preadaptations to life in the city). Dominant species in the city parks were:Nebria brevicollis, Patrobus atrorufus, Platynus assimilis, Notiophilus biguttatus, Pterostichus melanarius, Abax parallelopipedus, andCalathus piceus. The city parks were inhabited by a characteristic carabid fauna: the measure of proportional overlap ofSchoener with the carabid fauna in the wood was low. The same was true for the spider fauna in the botanical garden of Kiel (with 7 habitat types) in comparison to similar habitats in the surroundings. The diversity (index ofBrillouin) of the carabid fauna in the city parks was low; the diversity of the spider fauna in the botanical garden, however, was as high as in comparable habitats outside the city. The number of carabid species was correlated with the structural diversity of the green islands in the city, not with their area. 相似文献
228.
J Rubio-Guillén D González JJ Garde MC Esteso MR Fernández-Santos JE Rodríguez-Gíl N Madrid-Bury A Quintero-Moreno 《Reproduction in domestic animals》2007,42(4):354-357
Assisted sperm morphometry analysis (ASMA) was used in this study to determine the effects of cryopreservation on bull spermatozoa distribution in morphometrically distinct subpopulations. Ejaculates were collected from five bulls and were divided. One portion was diluted at 30 degrees C in a skim milk-egg yolk medium, containing glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for a minimum of 200 sperm heads were analysed from each sample by means of the Sperm-Class Analyser (SCA), and the mean measurements recorded. Our results showed that applying the ASMA technology and multivariate cluster analyses, it was possible to determine that three separate subpopulations of spermatozoa with different morphometric characteristics coexist in bull ejaculates (large, average and small spermatozoa). The mean values of each sperm head dimension among the three subpopulations of spermatozoa were significantly different (p < 0.001). Besides, there were significant (p < 0.001) differences in the distribution of these three sperm subpopulations between fresh and thawed samples. Thus, the percentage of representation of the subpopulation that includes those spermatozoa whose dimensions are the biggest, decreased from 52.06% in extended fresh samples to 15.51% in the thawed ones. Contrarily, the percent of representation of the subpopulation containing the smallest spermatozoa, increased from 8.70% in extended fresh samples to 34.04% in the thawed ones. In conclusion, the present study confirms the heterogeneity of sperm head dimensions in bull semen, heterogeneity that vary through the cryopreservation procedure. 相似文献
229.
Bacterial Isolates Associated With Dystocia And Retained Placenta In Iraqi Buffaloes 总被引:1,自引:0,他引:1
The present study was conducted on 50 recently calved Iraqi Buffalo cows. Depending on the kind of parturition, buffalo cows were divided into two main groups, the first group had normal unassisted parturition (NP) (26 animals) and the second group with certain periparturent complications (PPC) (24 animals). After 24 h of parturition, these two groups were further subdivided into two groups as cows expel their foetal membranes in <24 h postpartum and referred as non‐retained placenta (NRP) while cows that did not expel their foetal membrane after 24 h referred as retained placenta (RP). Sampling for bacteriology, uterine discharge for polymorphonuclear cells per cent and blood samples for polymorphonuclear neutrophil (PMN) and the enzyme creatine kinase activity were performed at 6, 24 and 48 h postpartum. In PPC group, the most prevalent bacteria after 6 h of calving were Escherichia coli, β‐haemolytic Streptococci and Lactobacillus acidophilus. Total bacterial isolates in the uterus of buffaloes with RP in PPC group after 24 and 48 h were 129 and 183 respectively. Among the isolates, Archanobacterium pyogenes, Fusobacterium necrophorum, Prevotella melaninogenicus and Staphylococcus aureus were the most prevalent isolates after 48 h of RP buffaloes in PPC group. Polymorphonuclear neutrophil were significantly (p < 0.01) increased in the uterine discharge than in blood in buffaloes with RP in both PPC and NP groups. In conclusion, uterine contamination occurs as a result of postpartum ascending contamination by non‐specific environmental organisms. The presence of Lactobacillus sp. in the uterus indicated a healthy uterus. Peripartum complications followed by retention of foetal membranes with the dominance of E. coli in the uterine lumen might favour the colonization of other bacteria including facultative anaerobic and strictly anaerobic in the uterine wall of buffaloes. 相似文献
230.
Accuracy of 3 Tesla magnetic resonance imaging using detection of fiber loss and a visual analog scale for diagnosing partial and complete cranial cruciate ligament ruptures in dogs
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Constance G. Fazio Peter Muir Susan L. Schaefer Kenneth R. Waller III 《Veterinary radiology & ultrasound》2018,59(1):64-78
Canine cranial cruciate ligament rupture is often bilateral and asymmetrical, ranging from partial to complete rupture. The purpose of our diagnostic accuracy study was to assess the accuracy of 3 Tesla magnetic resonance imaging (MRI) detection of fiber loss and use of a visual analog scale in the diagnosis of complete versus partial cranial cruciate ligament rupture in 28 clinical dogs with unilateral complete rupture and contralateral partial rupture. Three Tesla MRI was performed on 56 stifles using sagittal sequences (T2‐weighted fast spin echo with fat saturation, proton density fast spin echo, and T2‐weighted 3D fast spin echo CUBE). Two MRI observers assessed the cranial cruciate ligament for fiber loss and completed a visual analog scale. The MRI data were compared to arthroscopy and clinical status. Accuracy classifying partial or complete rupture was assessed using receiver operating characteristic analysis. Compared to arthroscopy, for complete cranial cruciate ligament rupture, sensitivity, specificity, and accuracy of MRI detection of fiber loss were 0.78, 0.50–0.60, and 0.68–0.71, respectively, and, for partial tears, specificity was 1.00. An MRI visual analog scale score ≥79 was indicative of complete cranial cruciate ligament rupture (sensitivity 0.72–0.94 and specificity 0.71–0.84). Using a visual analog scale cut‐point ≥79, observers achieved good accuracy discriminating clinical status of partial or complete cranial cruciate ligament rupture (area under the curve 0.87–0.93). MRI evaluation for fiber loss and use of a visual analog scale are specific in stifles with clinically stable partial cranial cruciate ligament rupture. In stifles with clinically unstable complete cranial cruciate ligament rupture, both MRI tests are sensitive though not specific compared to arthroscopy. As a diagnostic imaging method, MRI may help guide treatment in patients with cranial cruciate ligament damage, particularly for stable partial rupture. 相似文献