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1.
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   
2.
This study investigated the replacement of tumbling (intermittent vacuum tumbling for 6 h) with pressure treatment (7 MPa for 4 s) in the production of a cured ham product with the aim of elucidating if the pressure treatment could reduce the amount of salt added to obtain a satisfactory product. Confocal laser scanning microscopy (CLSM) revealed a pressure-induced loosening of the meat structure, and proton nuclear magnetic resonance (NMR) relaxometry revealed that this structural modification of the meat had an impact on water properties and water distribution in both cooked and cooked/fried products. Three salt levels (0.6, 1.1, and 1.7% w/w) were investigated, and sensory profiling revealed that the pressured-cooked meat obtained a significantly higher juiciness score at low and medium salt levels. In addition, sensory profiling assessments revealed that at the lowest salt concentration the pressured product was perceived to be saltier compared with the tumbled product; however, the difference was not significant and was absent upon frying. In contrast, in sensory time intensity analysis the maximum intensity and the total salt taste were significantly higher in the pressured samples at the low and medium salt levels in the cooked samples. In conclusion, the present study showed strong evidence that the structure and biophysical characteristics of cured ham is altered by pressurization and suggested that pressurization may reduce the critical amount of salt required in a ham product.  相似文献   
3.
The metabolic profile of calf rumen epithelial tissue was for the first time characterized by 1H NMR spectroscopy of chloroform/methanol extracts. The metabolite profiles comprised a number of amino acids, creatine, taurine, short-chain fatty acids and triglycerides. The effects of two dietary interventions; i) four levels of milk allowance with a concomitant different uptake of starter concentrate, and ii) two diets with varying content of starch and fibre in the concentrate, were elucidated. Partial least square regression analysis revealed that the intensity of NMR signals assigned to leucine, isoleucine and valine (0.90  ppm), propionate (1.06 and 2.18  ppm), lactate (1.32  ppm), butyrate (1.56  ppm), acetate (1.93  ppm), glutamine/glutamate (2.18, 2.35 and 3.75  ppm), creatine (3.04 and 3.94  ppm) and glycine (3.55  ppm) decreased with increasing milk allowance. In addition, the analysis revealed that the main difference between the two diets was the content of propionate in the epithelia tissue extracts. Previous morphological analyses of the same rumen epithelia were not able to detect any significant effects of either milk allowance or dietary starch content. Accordingly, the present study demonstrated that 1H NMR spectroscopy applied on extracts is a useful tool for metabolite profiling of epithelial tissue and for following the development of epithelia tissue in young calves, and that the technique may be more sensitive to dietary effects than morphological studies.  相似文献   
4.
FT-IR microspectroscopy and light microscopy were used to investigate pork muscle musculus semitendinosus samples, taken from three animals, that were subjected to brine salting at different concentrations (0.9, 3, 6, and 9% NaCl). Differences in spectral characteristics and in microstructure were observed in meat from animals differing in initial pH and varying salt concentrations. The FT-IR data displayed changes in the amide I region from 1700 to 1600 cm(-1). This spectral range was analyzed by principal component analysis (PCA) and partial least-squares regression (PLSR). These methods revealed correlations between the spectral data and the different animals, salt content, moisture content, pH value, and myofiber diameter. A shrinking share of alpha-helical components was related to an increase in salt concentration in the muscle. At the same time, a greater share in nonhydrogenated C=O groups (1668 cm(-1)) was related to an increase in salt concentration in the meat. The share of aggregated beta-strands differed with respect to the different animals but was not influenced by salt concentration. The meat at higher pHs (>6) had less aggregated beta-strands than that at lower pHs (5.6-5.7). It could be demonstrated that simultaneous with changes in microstructure, pH value, salt, and moisture content were alterations in the protein amide I region as measured by FT-IR microspectroscopy, revealing a relationship between these biophysical and chemical parameters and secondary protein structure attributes.  相似文献   
5.
Ohne Zusammenfassung Mit 2 Abbildungen.  相似文献   
6.
Control of spatiotemporal chaos is one of the central problems of nonlinear dynamics. We report on suppression of chemical turbulence by global delayed feedback using, as an example, catalytic carbon monoxide oxidation on a platinum (110) single-crystal surface and carbon monoxide partial pressure as the controlled feedback variable. When feedback intensity was increased, spiral-wave turbulence was transformed into new intermittent chaotic regimes with cascades of reproducing and annihilating local structures on the background of uniform oscillations. The global feedback further led to the development of cluster patterns and standing waves and to the stabilization of uniform oscillations. These findings are reproduced by theoretical simulations.  相似文献   
7.
Ingestion of broad bean seeds will precipitate an acute haemolytic anaemia (favism) in certain sensitive subjects. Aqueous extracts from both fresh and dried mature broad bean seeds, obtained from a favism-endemic area in Iran, were incubated with blood from favism-sensitive and control subjects. Changes in the reduced glutathione content of red blood cells were determined as an index of toxicity. The results showed that:
  1. The toxic principles in broad beans were at least partially water soluble.
  2. The seed coats of dry mature seeds and the flesh from fresh seeds had low toxicity.
  3. The immature whole seeds and the seed coats of fresh mature seeds were toxic.
  相似文献   
8.
Whole seed tubers have been reported to have performance advantages over seed tubers that have been cut, even if the cut tuber pieces are treated with a fungicide dust. For this study, whole seed tubers were compared to cut seedpieces and to cut seedpieces treated with four different commercial fungicide dusts for five consecutive seasons. A new field generation 3 Russet Burbank seed lot was used for each of the five years of this study. Both whole tubers and cut seedpieces were inoculated withFusarium spp., and the seedpieces were then treated with a fungicide dust. Inoculated and uninoculated untreated controls were also included. Emergence,Fusarium seed decay,Rhizoctonia stem canker, stem numbers, and vigor, as well as yield and grade data were obtained.Rhizoctonia stem canker in stems grown from whole seed tubers was significantly higher than in stems from seedpieces receiving fungicide treatment in several of the study years. Predicting whole seed tuber performance is difficult because performance varies more from year to year than performance of cut and treated seedpieces. Yield performance of whole seed tubers was not significantly better than cut and fungicide-treated seedpieces in any experimental year, and yield of large (over 280 g) tubers was significantly less than that recorded for two of the treatments when data from all five years were combined. This study demonstrated that untreated whole seed did not outperform cut and treated seedpieces for vigor, stem numbers, disease ratings, or yield in small plot comparisons for five consecutive seasons.  相似文献   
9.
Mature seeds of four Lupinus species,L. albus, L. angustifolius, L. luteus andL. mutabilis, have been analysed comprehensively to evaluate their potential for nutrition. Particular interest attaches to the comparison betweenlupinus species and soyabeans. All species are rich in high-quality protein, as judged from amino-acid profiles,In vitro studies indicate high levels of digestibility and imply the presence of few interfering factors. In contrast to many other legumes, lupinseeds are free of both protease inhibitors and haemagglutinins. Only one factor, a C-glycosyl poly-hydroxy flavone, which could conceivably interfere with protein absorption, has been identified. Lupinseed could possibly be developed as an oilseed crop, though oil contents are currently somewhat lower than those of soyabeans. The composition of lupinseed oil is similar to that of soyabean oil, both being limited in quality by the presence of linolenic acid. The bright yellow colour of the partially refined oil is due to the presence of the two carotenoids, β-carotene and zeaxanthin. Lupinseed is well-known to contain toxic alkaloids of the quinolizidine group. However, intensive breeding programmes involving all four named species have been in progress for many years. At least in the cases of the first three species, cultivars have been developed that are virtually alkaloid-free. Alkaloid profiles are of interest in being decisive chemotaxonomic indicators of species. The pyrimidine bases responsible for inducing favism through the consumption ofVicia faba are absent from lupinseed. Like soyabeans, lupinseed invariably contains a range of chemically complex saponins. Concentrations in the seed are of a similar order, but it is doubtful whether these should be considered significant anti-nutritional factors for Man. Lupinseeds contain a range of oligosaccharides—raffinose, stachyose and verbascose —which correspond with the flatus factors present in soyabeans and many other legumes. Levels, however, are no higher than those found in soyabeans.  相似文献   
10.
The aims of this study were to evaluate the prevalence and anatomical characteristics of thoracic caudal articular process dysplasia in French bulldogs, English bulldogs and Pugs presenting for problems unrelated to spinal disease. In this retrospective cross‐sectional study, computed tomography scans of the thoracic vertebral column of these three breeds were reviewed for the presence and location of caudal articular process hypoplasia and aplasia, and compared between breeds. A total of 271 dogs met the inclusion criteria: 108 French bulldogs, 63 English bulldogs, and 100 Pugs. A total of 70.4% of French bulldogs, 84.1% of English bulldogs, and 97.0% of Pugs showed evidence of caudal articular process dysplasia. Compared to French and English bulldogs, Pugs showed a significantly higher prevalence of caudal articular process aplasia, but also a lower prevalence of caudal articular process hypoplasia, a higher number of affected vertebrae per dog and demonstrated a generalized and bilateral spatial pattern more frequently. Furthermore, Pugs showed a significantly different anatomical distribution of caudal articular process dysplasia along the vertebral column, with a high prevalence of caudal articular process aplasia between T10 and T13. This area was almost completely spared in French and English bulldogs. As previously suggested, caudal articular process dysplasia is a common finding in neurologically normal Pugs but this also seems to apply to French and English bulldogs. The predisposition of clinically relevant caudal articular process dysplasia in Pugs is possibly not only caused by the higher prevalence of caudal articular process dysplasia, but also by breed specific anatomical characteristics.  相似文献   
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