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71.
Bertram HC Stagsted J Young JF Andersen HJ 《Journal of agricultural and food chemistry》2004,52(20):6320-6325
The effect of Gd-DTPA on the development in NMR relaxation of skeletal rabbit muscles post-mortem was investigated by dynamic low-field (0.47 T) relaxation measurements from 4 min post-mortem and until 23 h post-mortem. Twelve rabbits were included in the study, and half of the animals were administered 0.2 mmol of Gd-DTPA iv 15 min before sacrifice, while the other half was administered an isotonic salt solution. A significant effect of Gd-DTPA treatment corresponding to a 25% reduction in the T(1) relaxation time was observed. T(2) relaxation was decomposed into two components reflecting intra- and extracellular components (T(2)()alpha and T(2)()beta, respectively), and Gd-DTPA treatment was found to affect both components. However, around 150 min post-mortem a dramatic increase in the difference between control and Gd-DTPA-treated rabbits was observed in the relaxation time of the intracellular water population (T(2)()alpha). Electrical stimulation of the muscles resulted in a significantly earlier onset of the increased effect of Gd-DTPA on the T(2)()alpha population. The increased effect of Gd-DTPA treatment on the T(2)()alpha component is believed to reflect leakage of water from the muscle cells due to membrane destabilization, known to be promoted by electrical stimulation. Accordingly, the present study demonstrates how Gd-DTPA can be used for probing membrane integrity in post-mortem muscles known to be of importance for subsequent water distribution and final water-holding capacity. 相似文献
72.
Hønsi Torunn G. Stubberud Hege E. Andersen Sjur Stenersen Jørgen 《Water, air, and soil pollution》2003,142(1-4):27-37
In this study we have investigated the toxicity of soils from thetwo abandoned pyrite mines Ertelien and Konnerud in the southernpart of Norway. Soil samples were collected close to the pitheadof the mines, and earthworms were exposed to different concentrations of the contaminated mine soil mixed with commercial plant soil for a period of 14 days. Life-cycle responses such as growth and survival, as well as the biomarkerresponse lysosomal fragility were measured. The body burdens ofthe four heavy metals Cu, Cd, Zn and Pb were detected in the worms, and the body concentration of the metals generally increased with increasing heavy metal concentration in the soil.The growth and mortality of the earthworms were not influenced when exposed to any of the mine soil concentrations used. The lysosomal fragility of the earthworm coelomocytes measured by the neutral red retention time (NRR-time) was found to be markedly reduced in all the exposed earthworms. This assay seemsto be a sensitive and dose dependent endpoint for the toxicity assessment of heavy metal mixtures in pyrite mine soils. 相似文献
73.
Brit Lisa Skjelkvåle Kjetil Tørseth Wenche Aas Tom Andersen 《Water, air, and soil pollution》2001,130(1-4):1433-1438
Concentrations of sulphate in precipitation in southern Norway have decreased by 50–60% from 1980–1999. This has caused a decrease in sulphate concentrations in lakes of 30–40% from 1986–1999. Nitrogen in precipitation has decreased slightly over the last 10-years. In lakewater there has also been a significant but slight decrease. Concentrations of non-marine base cations in precipitation have decreased by 40% from 1980–1999. In lakewater, non-marine base cation concentrations have been at about the same level the last 10 years. This indicates that acid deposition has decreased sufficiently such that the pool of exchangeable base cations in the soil is now being replenished. The acidification situation in lakes in Norway has thus shown a clear improvement over the last 8–10 years. pH, alkalinity and ANC (acid neutralising capacity) have all increased. Concentrations of inorganic (toxic) aluminium species have decreased. The trends in H+ and Aln+ do not follow the relation expected if Aln+ concentrations were governed solely by a single solid phase of Al(OH)3. 相似文献
74.
Potential antioxidants in beer assessed by ESR spin trapping 总被引:5,自引:0,他引:5
A number of potential antioxidants have been evaluated for their effect on formation of radicals in beer using the electron spin resonance (ESR) lag phase method. Sulfite was found to be the only compound that was able to delay the formation of radicals, whereas phenolic compounds such as phenolic acids, catechin, epicatechin, and proanthocyanidin dimers had no effect on the formation of radicals. Ascorbate, cystein, and cysteamin were on the other hand found to be prooxidants. It is suggested that antioxidants must be able to either scavenge peroxides or trap metal ions in order to be effective in beer. The effectiveness of sulfite is suggested to be a consequence of its two-electron nonradical producing reaction with peroxides. 相似文献
75.
Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season 下载免费PDF全文
The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p < .05) and monocytes (2.93 ± 0.13; p < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer. 相似文献
76.
D Priya NL Selokar AK Raja M Saini AA Sahare N Nala P Palta MS Chauhan RS Manik SK Singla 《Reproduction in domestic animals》2014,49(2):343-351
The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT. 相似文献
77.
Time trends in animal-disease surveillance often are evaluated on the basis of crude estimates of apparent prevalence. In addition to possible changes in the true prevalence of the condition, changes in apparent prevalence over time might reflect changes in sensitivity and/or specificity of the diagnostic classification used. To illustrate this, comparative post-mortem meat inspection data from four Danish slaughter plants sampled in 1993-1994 and 1997-1998 were used to obtain latent-class model estimates of the sensitivity and specificity of traditional and extended post-mortem meat inspection of visceral and parietal chronic pleuritis (CP), respectively.True prevalence of CP was estimated for each study period and slaughter plant by latent-class models. Estimated sensitivities of traditional post-mortem meat (TPM) inspection ranged from 28.8 to 61.4% (1993-1994) and 39.2 to 87.3% (1997-1998). An increase in sensitivity with time was seen for all slaughter plants. Estimated sensitivities of extended post-mortem meat (EPM) inspection ranged from 85.7 to 94.8% (1993-1994) and 73.8 to 93.0% (1997-1998). All estimated specificities were >93.3%.The possible association of the estimated true prevalence of CP with time (1993-1994 versus 1997-1998) was investigated with a logistic-regression model with random effects. A slight, but non-significant decrease in the odds of CP from 1994 to 1998 was found (odds ratio=0.9).In this and similar situations, one should consider conducting ongoing double-classification of samples of units followed by statistical estimation of true prevalences, sensitivities and specificities, so that decisions can be based on such estimates rather than on crude apparent prevalences. 相似文献
78.
79.
DW Bartlett JM Clough JR Godwin AA Hall M Hamer B Parr‐Dobrzanski 《Pest management science》2004,60(3):309-309
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry 相似文献
80.
Influence of Disease Process and Duration on Acute Phase Proteins in Serum and Peritoneal Fluid of Horses with Colic 下载免费PDF全文
T.H. Pihl E. Scheepers M. Sanz A. Goddard P. Page N. Toft P.H. Andersen S. Jacobsen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(2):651-658