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101.
Eosinophilic enteritis (EOE) is a type of inflammatory bowel disease and is characterized clinically by chronic obstinate diarrhea. Three Japanese Black (JB) fattening cattle (2 males and 1 female) on different cattle farms presented with chronic episodic diarrhea without fever or dehydration. Soft reddish spherical carneous tissues (1−3 cm) were occasionally excreted within the diarrheic feces. Administration of antibiotics, antidiarrheal drugs and vermicides had no therapeutic effect, but dexamethasone improved the fecal characteristics. The symptoms persisted until the animals were slaughtered at 27–30 months of age. Histopathological examination of the intestines revealed marked eosinophilic infiltration in the lamina propria and submucosa. From these findings, we diagnosed these cattle as the first cases of EOE in JB cattle.  相似文献   
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Silk fibroin (SF) fiber from theAntheraea pernyi silkworm was treated with a 1.23 N iodine-potassium iodide (I2-KI) aqueous solution, and the structure and physical properties were investigated to clarify the effects of the iodine treatment. The noticeably high weight gain value of SF fiber, about 25 wt% was attributed to the absorption of polyiodide ions in the form of I3 ? and I5 ?. Fourier transform infrared spectroscopy and X-ray diffraction measurements suggested that polyiodide ions mainly entered the amorphous region. In addition, a new sharp reflection on the meridional direction, corresponding to a period of 7.0 Å, was observed and indicated the possibility of the formation of mesophase structure ofβ-conformation chains. Dynamic viscoelastic measurements showed that the damping tanδ peak at 270°C gradually shifted to lower temperature in the iodinated SF fibers, suggesting an enhancement of the molecular motion of the fibroin chains induced by the presence of polyiodide ions. With heating above 254 °C, the iodine component introduced intermolecular cross-linking of SF, and the melt flow of the sample was inhibited. The thermal decomposition stability of fibroin molecules was greatly enhanced by iodine treatment.  相似文献   
107.
For better understanding of the physiological function of anthocyanins, the absorption and metabolism of cyanidin 3-O-beta-D-glucopyranoside (Cy3G), which is one of the major anthocyanins in colored food materials, were precisely investigated. Combining two modalities newly developed, that is, highly sensitive semi-micro-HPLC and vein cannulation, Cy3G and its four major metabolites (M1-M4) were detected in the blood plasma of rats after oral administration of Cy3G (100 mg/kg of body mass). The plasma concentration of Cy3G reached its maximum at 15 min after the ingestion. Metabolite 2 (M2) and metabolite 3 (M3) showed their maximum plasma levels at 15 and 30 min, respectively, whereas metabolite 1 (M1) and metabolite 4 (M4) showed their maximum levels at 60 and 120 min, respectively. The maximum plasma concentrations of the four metabolites were in the following order: M3 (21 nM) > M4 (20 nM) > M1 (8.5 nM) > M2 (5 nM). When Cy3G was directly injected into the neck vein, only M2 and M3 were detected in the plasma, indicating that both M1 and M4 were produced during absorption from the gastrointestinal tract. Tandem MS analysis of the metabolites showed that M2 and M3 were monomethylated Cy3G, while M1 and M4 were glucuronides of Cy and methylated Cy, respectively. M3 was assigned as peonidin 3-O-beta-D-glucopyranoside (Pn3G) from the comparison of the retention time of authentic Pn3G.  相似文献   
108.
The previous experiences1-3) with incubation experiments of the soils under submargd condition indicated that the disappearance of molecular oxygen and nitrates occurred shortly after sub-emerging, and then the reduction of ferric iron proceeded, being followed by the reduction of sulfates and the formation of methane which nre caused by the activities of strict anaerobes. It was suggested from the above fact that the reduction process in the submarged soils was affected mainly by two factors: namely, the amount of reducible ferric iron and the soil organic matters which are avaiable as substrate for microbial metabolism.  相似文献   
109.
Several trials to obtain information on the living microorganisms at micro-sites of the submerged soil by the novel utilization of the tetrazolium salts were described. Results are summarized as follows:

(1) The air-dried soil was incubated with TIC (triphenyl tetrazolium chloride) under submerged condition according to the modified double layer plate method. The red formazan (the reduced product of TIC) was precipitated at the biologically active sites by the dehy. drogenase activity. Using a binocular microscope, most of the biologically active sites were found to be localized on and around the organic debris.

(2) The amount of nitrogen mineralized by incubating the soil under submerged condi. tion correlated well not only with the amount of formazan formed biologically in the submerged soil but also with the amount of formazan formed non-biologically by heating the soil with TIC in Ba(OH). solution. In addition, the pattern of precipitation of the nonbiologically formed formazan was very similar to that of the biologically formed formazan. Accordingly, the substances which reduced TIC non-biologically were considered to be closely associated with the substrates for the microorganisms.

(3) The plant debris stained with the red formazan could be mounted on a slide glass and observed at high magnification for the detailed study on the process of decomposition. Addition of lactophenol cotton blue to the plant debris could visualize the microorganisms responsible for the decomposition of the plant debris.

(4) NTB (nitro tetrazolium blue) was the most suitable for staining individual microorganisms growing on cellulosic materials or plant debris. The double staining with NTB and rosebengal made the discrimination between dead or resting cells and viable ones possible when this technique was applied to the decomposed filter paper.  相似文献   
110.
Abstract

We previously analyzed the effect of nitrate dispersion on the apparent nitrogen isotope fractionation factor associated with denitrification in soil (Kawanishi et al. 1993), and found that the dispersion effect was significant when the water flow was slow. In the previous report, we assumed that the dispersion coefficients of 14NO3 ? and 15NO3 ? were similar. However, when the water flow is slow, molecular diffusion will dominate mechanical dispersion and the above assumption may not be valid.  相似文献   
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