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71.
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在兽医及肉品检验中,测定分枝杆菌对预防其在动物群体内及动物和人之间的传染扩散具有重要意义。在瑞典从外观健康屠宰猪的患有淋巴结炎的颌下淋和肠淋通常能分离到非典型分枝杆菌。在肉品检验,取样进行微生物学检查污染较为严重,因此需要一种敏感的、选择性的分离技术。  相似文献   
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To determine the effects of lifting time and storage on water-stress resistance of nursery-grown white spruce (Picea glauca (Moench) Voss) seedlings, we compared gas exchange, water relations and mortality of 3-year-old seedlings lifted in October 1991 and stored at -2 degrees C for 3 months with seedlings lifted in January 1992. The seedlings were placed in nutrient solution and subjected to -1.1 or -2.7 MPa water stress induced by polyethylene glycol 3350 for 9 days. Water stress, but not lifting time, had a significant effect on seedling net assimilation, symplastic volume and turgor loss point. In a second experiment, seedlings lifted in October 1991 were stored at -2 degrees C for 7 months and compared with seedlings lifted in May 1992. The seedlings were planted in pots, and their gas exchange and water relation parameters measured in response to gradual water stress. The results suggest that prolonged cold storage retards photosynthetic recovery of seedlings after planting. Higher rates of net assimilation in seedlings lifted in May were not directly related to their water status. Nonstomatal limitations were the primary factor influencing photosynthetic rate. We conclude that the inferior ability of cold-stored seedlings to tolerate water stress was due to poor osmotic adjustment and a lag in recovery of photosynthesis.  相似文献   
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Fourier transform mid-infrared (FT-IR) spectroscopy was investigated as a method of analysis for trans fatty acid content of cereal products without the need for prior oil extraction. Spectra were obtained, with an FT-IR spectrometer equipped with an attenuated total reflectance (ATR) device, of ground samples pressed onto the diamond ATR surface, and trans fatty acids were measured by a modification of AOAC Method 996.01. Partial least-squares (PLS) models were developed for the prediction of trans fatty acids in ground samples using several wavenumber selections on the basis of bands related to lipids. The models (n = 79) predicted trans fatty acids in ground samples with standard error of cross-validation (SECV) of 1.10-1.25 (range 0-12.4) % and R2 of 0.85-0.88 and in validation samples (n = 26) with standard error of performance (SEP) of 0.96-1.12 (range 0-12.2) % and r2 of 0.89-0.92, indicating sufficient accuracy for screening. Sample trans fatty acid % was predicted as accurately with the fingerprint region (1500-900 cm(-1)) as with the entire range (4000-650 cm(-1)) indicating, in concert with the regression coefficients, the importance of the isolated trans double bonds at 966 cm(-1) in development of the model. Data is also presented on prediction of trans fatty acids using the spectra of residual oil films on the ATR surface after removing the solid portion of the sample.  相似文献   
78.
White wines are generally low in polyphenol content as compared to red wines. However, Champagne wines have been shown to contain relatively high amounts of phenolic acids that may exert protective cellular actions in vivo. In this study, we have investigated the potential neuroprotective effects of Champagne wine extracts, and individual phenolics present in these extracts, against peroxynitrite-induced injury. Organic and aqueous Champagne wine extracts exhibited potent neuroprotective activity against peroxynitrite-induced injury at low concentrations (0.1 microg/mL). This protection appeared to be in part due to the cellular actions of individual components found in the organic extracts, notably tyrosol, caffeic acid, and gallic acid. These phenolics were observed to exert potent neuroprotection at concentrations between 0.1 and 10 microM. Together, these data suggest that polyphenols present in Champagne wine may induce a neuroprotective effect against oxidative neuronal injury.  相似文献   
79.
OBJECTIVE: To validate a new food-frequency questionnaire (FFQ) for measuring the intake of fruit, vegetables and tea reported by women participating in the Norwegian Mother and Child Cohort Study (MoBa). DESIGN: Intake of fruits, vegetables and tea estimated by the FFQ was compared with urinary flavonoid excretion, plasma carotenoid concentration and intake measured by a 4-day weighed food diary (FD). The triangular method was applied to calculate FFQ validity coefficients using two independent biomarkers. SETTING AND SUBJECTS: One hundred and nineteen women participating in MoBa. RESULTS: The FFQ estimate of fruit intake was significantly correlated with urine phloretin (r = 0.33), citrus fruit/juice with urine hesperetin (r = 0.44), cooked vegetables with plasma alpha-carotene (r = 0.37), and tea with urine kaempferol (r = 0.41) (P < 0.01 for all). On average, 60% of the participants fell into the same or adjacent quintiles when classified by FFQ and biomarkers. Significant correlations between the FFQ and FD were found for fruit (r = 0.39), vegetables (r = 0.34), juices (r = 0.50) and tea (r = 0.53). The FFQ validity coefficient was 0.65 for citrus fruit/juice and 0.59 for cooked vegetables as calculated by the triangular method. CONCLUSIONS: The validation study shows that the MoBa FFQ can be used to estimate fruit, juice, vegetable and tea intake in pregnant Norwegian women, and to rank individuals within the distribution.  相似文献   
80.
The eyes are a common site of injury in agricultural operations. Identification of the cause of injury is important to inform preventive interventions. The objective of this study was to describe the hazards and mechanisms of acute traumatic injury to the eyes of agricultural workers who are hired in farming operations on a seasonal basis. A review of the literature was performed to summarize the mechanisms of eye injuries in agriculture. Field observations and informal interviews were performed to verify the literature and to determine whether there are eye hazards for farm workers that have not been reported in the literature. Additional mechanisms of injury were elicited, and suggested methods of injury prevention are presented here.  相似文献   
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