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71.
Welsh JB Best SJ Yager JA Foster RA 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(7):764-766
Seven cases of feline vulval adenocarcinoma are reported. Follow-up information was available for 5 cats, and all but 1 of these was euthanized within 2-18 mo of diagnosis (median 9.2 mo) for reoccurrence of local disease (3 cases) and/or clinical signs consistent with metastases (3 cases). There was no relationship between histological features of the tumor and outcome. 相似文献
72.
Herrero AM Carmona P López-López I Jiménez-Colmenero F 《Journal of agricultural and food chemistry》2008,56(16):7119-7124
Raman spectroscopy, texture, proximate composition, and water binding analysis were carried out to evaluate the effect of thermal treatment and/or salt addition to meat batter. For this purpose, different meat batters were elaborated: control meat batter (no salt) and meat batters with low (1.0%) and high (2.5%) NaCl content with and without thermal treatment (70 degrees C/30 min). Increase (P < 0.05) in penetration force and hardness upon heating was observed. Results also showed hardness increasing (P < 0.05) as a function of salt addition in heated meat batter. Raman spectroscopy analysis revealed a significant (P < 0.05) decrease in alpha-helix content accompanied by an increase (P < 0.05) in beta-sheets resulting from heating. Significant (P < 0.05) correlations were found between these secondary structural changes in meat proteins and water binding and textural properties of meat batter. In this way, a significant correlation was found between beta-sheets, salt content, hardness, and chewiness in heated samples. 相似文献
73.
This experimental study examines the relationship between texture and microfabric under isotropic stresses generated by wetting and drying. This can be achieved by observing and measuring the reorganization of microfabrics (plasmic fabrics and related distribution pattern, RDP). Microfabrics are produced in the laboratory by mixing montmorillonite with various proportions of sand and silt, and subjecting them to wetting and drying without confinement. Thin sections are cut to study their microfabrics. Results show broad and systematic variations in fabric with changes in texture. Fine matrix (silt plus clay in physical continuity) is developed in samples with low sand:silt ratio, and regardless of this ratio at high clay levels. Coarse porphyric and fine porphyric RDP are formed at low and high clay contents, respectively. Plasmic fabrics are represented mainly by insepic and weakly developed mosepic and masepic fabrics in the matrix in the form of small plasma separations with random orientation, and weak skelsepic plasma as embedded grain argillans. On the other hand, coarse matrix (sand grains in physical continuity) dominates the sandy samples which are associated with relatively thick and strongly birefringent free grain argillans giving well-developed skelsepic fabric. The RDP follows two major paths: beginning with orthogranic (very low clay content) along the iunctic sequence at low clay:silt ratio and along the chlamydic sequence at high ratio. The regularities in fabric development are interpreted in the light of the dynamic properties and behaviour of the active clay fraction in a clay-water system. The pedogenetic implications of the results are explored, and the term “erdic” fabric defined. 相似文献
74.
Bienvenue A Jiménez-Flores R Singh H 《Journal of agricultural and food chemistry》2003,51(22):6488-6494
Heat treatment during manufacturing of milk powder is one of the most important tools for manipulation of its functional properties, and it is the basis of the classification of these proteins into low-, medium-, and high-heat types. Slight differences in the sequences of the major proteins in milk (genetic variants) seem to have also a significant effect in milk powder processing (U.S. patent). Therefore, the effects of high-temperature storage and heat treatment on skim milk of defined genetic variants of beta-lactoglobulin (beta-LG) were measured. The samples had 45% total solids, the temperature of aging was 50 degrees C, and the heat treatment was 90 degrees C for 10 min prior to evaporation. Measurements on shear rate and on apparent viscosity were determined for each sample. During storage of the concentrated milk, the apparent viscosity and yield values increased markedly, and the age-dependent increase in viscosity in heat-treated concentrated skim milks was much more pronounced than in those prepared from unheated skim milks. The increase in apparent viscosity and yield value with storage time was notably different for milks containing different genetic variants. Unheated concentrated milks containing the B variant of beta-LG showed the most rapid increase in apparent viscosity with storage time, whereas the viscosity increase was slowest in the concentrate containing the A variant. In contrast, heat-treated concentrated milks containing the A variant of beta-LG showed the most rapid increase in viscosity with storage time, whereas the viscosity increase was slowest in the concentrate containing the AB variant. The changes in apparent viscosity of concentrated milk were largely reversible under high shear during the early stages of storage, but samples stored for a long time showed irreversible changes in apparent viscosity. Particle size analysis confirmed irreversible aggregation and fusion of casein particles during storage. 相似文献
75.
Jim Reynolds 《Biological conservation》2003,114(2):306-307
76.
Summary The first backcross and F2 progenies from triploid F1 and tetraploid F1 hybrids between B. napus and 2x and 4x B. oleracea ssp. capitata (cabbage) were studied for their general morphology, resistance to race 2 of the clubroot pathogen, chromosome number and meiotic chromosome behavior. No linkage was apparent between resistance and the major morphological characters. Unreduced gametes played a large part in the successful formation of seed of the B1 and F2 progeny. B1 plants with low chromosome numbers were selected for use in recurrent backcrosses. The potential use of anther culture to extract gametic progenies from resistant B1 and F2 plants with higher chromosome numbers was suggested. The presence of homoeologous pairing observed in all the plants is considered advantageous for selecting suitable progeny in later generations. 相似文献
77.
Debranning of wheat affects flour quality, initially by altering the breakage of wheat kernels during first break. The double normalized Kumaraswamy breakage function was applied to model the effect of debranning on wheat breakage during first break milling, in which type 1 breakage describes a relatively narrow distribution of midsized particles, whereas type 2 breakage describes a wide size range of predominantly small particles extending to very large particles. Mallacca (hard) and Consort (soft) wheats were debranned and milled at three roll gaps under sharp‐to‐sharp and dull‐to‐dull dispositions. Type 1 breakage increased at longer debranning times, whereas type 2 breakage decreased, for both wheat varieties under both dispositions. Sharp‐to‐sharp milling tended to produce more type 1 breakage than dull‐to‐dull. A mechanism of wheat breakage is proposed to explain the coproduction of very large and small particles via type 2 breakage and, hence, the effect of debranning. The proposed mechanism is that small particles of endosperm arise from scraping of large flat particles of wheat bran under the differential action of the rolls, such that removal of the bran reduces the production of the large bran particles and thus reduces the opportunity for the scraping mechanism that produces the very small particles. 相似文献
78.
P. Jiménez O. Ortiz D. Tarrasón M. Ginovart M. Bonmatí 《Biology and Fertility of Soils》2007,44(2):393-398
This work has evaluated the effects of thermally dried (TDS) or composted (CDS) dewatered sewage sludge on β-glucosidase activity,
total (TCH) and extractable (ECH) carbohydrate content, microbial biomass carbon and basal respiration of soils from limestone
quarries under laboratory conditions. Two doses (low and high) of the dewatered sludge (DS) or of the respective TDS or CDS
were applied to a clayey and a sandy soil, both coming from working quarries. The soil mixtures and the controls (soils with
no added sludge) were incubated for 9 months at 25°C and 30% of field capacity. The addition of sludge increased all the studied
soil parameters, and the increase depended on the amount of sludge. Except in the case of TCH and ECH, the enhancing effect
decreased with time, but at the end of incubation, parameters of the treated soils were higher than those of the control.
The rank order of the initial stimulating effect was soil–TDS ≥ soil–DS ≥ soil–CDS, and probably, this order depended on the
proportion of stable organic matter, which was the lowest in the TDS. Values of metabolic quotient (qCO2) were higher at the lower dose, and they did not change during incubation in the CDS-treated soils. Both TCH and ECH were
the parameters with the greatest significant sludge and dose effects. Basal respiration, microbial biomass carbon and β-glucosidase
activity were the best measured parameters in distinguishing the long-term effects of the three sludge types over the soils. 相似文献
79.
A. Grant P. S. Belton I. J. Colquhoun M. L. Parker J. J. Plijter P. R. Shewry A. S. Tatham N. Wellner 《Cereal Chemistry》1999,76(2):219-226
The effects of lipids and residual starch components of wheat flour gluten on gluten hydration properties were investigated using nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) techniques. Whole or native, lipid-free, starch-free, and lipid- and starch-free gluten samples were prepared from wheat (Triticum aestivum) cv. Mercia. 2H NMR relaxation on gluten samples hydrated with deuterium oxide (D2O) was measured over a 278–363 K temperature range. FTIR spectra were recorded in dry and fully hydrated material. Transverse relaxation (T2) results indicated that all four gluten samples were hydrophilic in nature. There was little difference in relaxation behavior of whole and lipid-free gluten samples. T2 values and populations of the relaxation components were very similar in each. The FTIR spectra of both samples showed an increase in extended β-sheet secondary structures on hydration. These results suggest that lipid binding in gluten, if it occurs, has little effect on wheat gluten properties. Adding starch to the gluten matrix results in an increase in water sorption on heating that may be attributed to the effects of starch gelation. However, the whole water uptake of the gluten cannot be accounted for by the contribution of the residual starch, as estimated by the effects of added starch. Extraction of residual starch required solubilization of the protein, including breaking of the disulfide bonds. This process altered the gluten structure and properties. Light microscope investigation showed that glutens with residual starch extracted were unable to form fibrillar strands on hydration. NMR and FTIR results showed greater water sorption in both samples with extracted starch than in the unextracted samples. 相似文献
80.
Grazing livestock excrete large volumes of faecal material on pasture. Understanding the magnitude of this faecal burden is important for attributing sources of agricultural pollutants to different spatial and temporal scales. This field-based study evaluated the utility and transferability of a rapid approach often used in plant ecology (the line intercept method (LIM)) for estimating faecal burden from grazing cattle on pasture. Results from the LIM were of equivalent magnitude, with no significant difference observed, to those derived from more time-consuming sampling of faecal material from pasture using a quadrat-style methodology (herein termed burden sampling). However, the variability in estimates using the LIM was much larger (839?C7,079?kg fresh weight faeces over the 50,000?m2 field) compared with estimates provided by the burden sampling of pasture at 0.2?% area sampled (1,616?C3,979?kg/50,000?m2), 0.4?% area sampled (1,753?C2,723?kg/50,000?m2) and 0.8?% area sampled (1,212?C2,344?kg/50,000?m2). The LIM offers a rapid and cost-effective alternative to time-consuming sampling campaigns of faecal burden on pasture and provides estimations that are preferable to back-of-the-envelope calculations based on the over-simplification of livestock excretion rates. 相似文献