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101.
A 7‐year‐old male Boxer with a 3.5‐year history of atopy and food hypersensitivity was presented with multiple poorly circumscribed nodules and maculae of the skin and tongue, and jaundiced mucosal membranes. Cytologic and histopathologic examination of the skin lesions revealed cutaneous epitheliotropic lymphoma. Cells were CD3+ and CD8+ in flow cytometry. The CBC showed a moderate leukocytosis with 16% atypical lymphocytes with irregularly cleaved nuclei. Flow cytometric phenotyping of peripheral blood showed an elevated proportion of the CD8+ T‐lymphocyte subpopulation, indicating a malignant population of T‐cell origin, and the electropherogram of the PCR antigen receptor rearrangement produced a monoclonal peak for TCRγ. Liver enzyme activities were markedly increased and abdominal ultrasound examination showed increased echogenicity of the liver and enlarged abdominal lymph nodes. Fine‐needle aspirates of the liver confirmed infiltration with lymphocytes exhibiting the same morphology as the cells detected in skin and peripheral blood. Treatment was induced with L‐asparaginase, lomustine, and prednisone. Partial clinical remission of the skin and tongue lesions was achieved within 10 days, and hematologic abnormalities resolved. Despite further treatment with L‐asparaginase and lomustine, the dog relapsed within one month and was euthanized. Presence of malignant lymphocytes in skin, peripheral blood, and liver indicate a rare variant of leukemic cutaneous T‐cell lymphoma, equivalent of Sézary syndrome in a dog. This case report describes the use of flow cytometry as a complementary tool for lymphocyte characterization of skin lesions for the first time.  相似文献   
102.
Ohne Zusammenfassung  相似文献   
103.
For vaccine licensing data about efficiency and duration of protection are essential. Within the scope of the developement of a new subunit vaccine against Actinobacillus pleuropneumoniae (A.pp.) the protective efficiency over the whole length of the fattening period must be proven. This required infection experiments in finishing pigs. Eight pigs in the age of six months were infected experimentally into the trachea with an A.pp. serotyp 2 strain. To our knowledge data about the susceptibility of pigs of this age do not exist, so that the infectious dose for pigs of this age and this route of infection had to be determined. Two pigs each were infected with different doses of 10(10), 6 x 10(5), 8 x 10(3) and 2 x 10(3) CFU (colony forming units). The aim of the study was to produce a typical pleuropneumonia with fever and severe respiratory symptoms as well as characteristic pathomorphological lung alterations without loss of animals during the acute stage of infection. The pathogen should be cultivated from lung tissue. The recommended dose for testing the efficiency of vaccines turned out to be approximately 10(3) CFU A.pp. serotyp 2.  相似文献   
104.
To study the responses of Scots pine (Pinus sylvestris L.), a commercially important tree species in Europe, to future increases in atmospheric CO2 concentration ([CO2]), we grew saplings for 4 years in the ground in open-top chambers in ambient or ambient + 400 micromol mol(-1) CO2, without supplemental addition of nutrients and water. Carbon (C) budgets were developed for trees in both CO2 treatments based on productivity and biomass data obtained from destructive harvests at the end of the third and fourth years of treatment, and simulations of annual gross photosynthesis (P(tot)) and maintenance respiration by the model MAESTRA. Simulated P(tot) was enhanced by elevated [CO2], despite significant down-regulation of photosynthetic capacity. The subsequent increase in C uptake was allocated primarily to tissues with limited longevity (needles and fine roots), which explains why the measured annual increment in woody biomass did not differ between CO2 treatments. Thus, our results suggest that accelerated stem growth only occurs in the first 2 years in the presence of elevated [CO2] and that forest rotations will not be shortened significantly in response to increasing [CO2]. In elevated [CO2], a higher proportion of available C was allocated below ground, resulting in altered biomass distribution patterns. In trees of equal size, measured ratios of fine root/needle biomass and belowground/aboveground biomass were almost twice as large in the elevated [CO2] treatment. Although there are uncertainties in scaling from saplings to mature canopies, the data indicate that, in nutrient-limited Scots pine forests, elevated [CO2] is unlikely to accelerate tree growth significantly, but is likely to increase C inputs to soil.  相似文献   
105.
The impact of heat treating wheat flour (for 2 or 5 h at 80 or 100°C) on its functional properties was studied with solvent retention capacity (SRC) tests and related to changes in individual groups of flour constituents. Heat treatments increased the overall water retention capacity (from 55.6% for control flour to 62.4% for flour heated 5 h at 100°C) as well as sucrose SRC (from 85.0 to 113.5%), although no changes were observed in sodium carbonate SRC. The decrease in lactic acid SRC values (from 113.1 to 97.4%) indicated that heat treatment restricted swelling of the protein network. As deduced from a decrease in both the level of proteins extractable in sodium dodecyl sulfate–containing medium and the level of free sulfhydryl groups, the restricted swelling was related to protein cross‐linking within the flour particles. Such upfront polymerization prevented proper hydration and gluten network formation during mixing. Starch (swelling) properties were also affected by heat treatment. Finally, the impact of heat treatment on flour SRC profiles was comparable to that noted when chlorinating wheat flour.  相似文献   
106.
107.
The effect of nitrogen (N) supply and weeds on grain yield of spring barley was investigated from 1997 to 2004 in an organic farming crop rotation experiment in Denmark on three different soil types varying from coarse sand to sandy loam. Two experimental factors were included in the experiment in a factorial design: (1) catch crop (with and without), and (2) manure (with and without). The crop rotation included grass-clover as a green manure crop. Animal manure was applied as slurry in rates corresponding to 40% of the N demand of the cereal crops.

Application of 50 kg NH4-N ha−1 in manure (slurry) increased average barley grain DM yield by 1.0–1.3 Mg DM ha−1, whereas the use of catch crops (primarily perennial ryegrass) increased grain DM yield by 0.2–0.4 Mg DM ha−1 with the smallest effect on the loamy sand and sandy loam soils and the greatest effect on the coarse sandy soil. Model estimations showed that the average yield reduction from weeds varied from 0.2 to 0.4 Mg DM ha−1 depending on weed species and density. The yield effects of N supply were more predictable and less variable than the effects of weed infestation. The infestation level of leaf diseases was low and not a significant source of yield variation.

The apparent recovery efficiency of N in grains (N use efficiency, NUE) from NH4-N in applied manure varied from 29 to 38%. The NUE of above-ground N in catch crops sampled in November prior to the spring barley varied from 16 to 52% with the largest value on the coarse sandy soil and the smallest value on the sandy loam soil. A comparison of grain yield levels obtained at the different locations with changes in soil organic matter indicated a NUE of 21–26% for soil N mineralisation, which is smaller than that for the mineral N applied in manure. However, this estimate is uncertain and further studies are needed to quantify differences in NUE from various sources of N.

The proportion of perennial weeds in total biomass increased during the experiment, particularly in treatments without manure application. The results show that manure application is a key factor in maintaining good crop yields in arable organic farming on sandy soils, and in securing crops that are sufficiently competitive against perennial weeds.  相似文献   

108.
When used in bread dough systems, glucose oxidase (GO) and pyranose oxidase (P2O) generate H2O2 from O2. We here studied their potential to improve dough and bread characteristics. Neither GO nor P2O significantly affected the volume of straight dough bread produced with fermentation and proofing times of respectively 90 and 36 min at dosages up to 0.50 nkat/g flour. Supplementation with 1.00 nkat/g flour of GO or P2O significantly decreased bread loaf volume. The resistance of dough (fermented for 20 min and proofed for 56 min) to an applied shock was substantially improved by inclusion of 0.08, 0.25, 0.50 or 1.00 nkat/g flour of GO or P2O in the dough recipe. Thus, the proofed doughs showed significantly less collapse and the resultant breads had higher loaf volumes than did the reference breads. Yeast probably exerts an oxidizing effect on dough, which, depending on the exact breadmaking protocol used, might veil the positive oxidizing effect of the enzymes on dough properties during prolonged fermentation.  相似文献   
109.
110.
Fractionation of tryptic gliadin hydrolysates based on proline levels   总被引:1,自引:0,他引:1  
The central domain (CD) and terminal domains (TDs) of wheat gliadins contain high and low levels of the amino acid proline (Pro), respectively. The CD is rather hydrophilic while the TDs are rather hydrophobic and contain most of the ionisable amino acids, although present only in low levels. Therefore, peptides derived from the CD or TDs may strongly differ in their physico–chemical properties. Trypsin cleaves peptide bonds at lysine and arginine residues which are mainly present in the TDs and was used in the present study. Several fractionation methods were examined to isolate CD and TD related peptides from tryptic hydrolysates. Pro was used as a marker for CD and TD related peptides. Both semi-preparative reversed-phase HPLC separation and fractionation of the water-soluble peptides of the tryptic gliadin hydrolysates by graded ethanol precipitation resulted in peptide fractions with different Pro levels. Whereas the fractions precipitating up to 90% ethanol were Pro rich, a Pro poor fraction consisting of small peptides was soluble in 90% ethanol solution. The water insoluble peptides of the tryptic hydrolysates also showed a low Pro level. Ultrafiltration of the water-soluble peptides using a 5-k membrane resulted in small Pro poor peptides and larger Pro rich peptides.  相似文献   
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