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101.
A total of 39 Holstein cattle were grazed in tracts of wild grassland on account of shortage in pasture grass. Twenty-nine cattle were affected and 26 of them died during a 21-day period. The main signs were depression, anorexia, ascites, and oliguria. There was elevated serum urea nitrogen and sugar and protein in the urine. Pathological examination revealed turbid swelling of the kidney, an increase in the amount of fluid in the body cavity, edema in the perirenal adipose tissue and hemorrhage in various visceral organs and tissues. Histologically, acute tubular necrosis in the kidney, hypoplasia of the erythroblast series in the bone marrow, atrophy and degeneration of the lymphatic tissue and focal necrosis of the liver were observed in many of the cattle. Among cows experimentally fed Narthecium asiaticum Maxim., Polygonum sachalinense Fr. Schum., and Vitis coignetiae Pulliat which were presumed to have been ingested in large amounts by grazing cattle in the field, the cows fed N. asiaticum revealed the clinical, biochemical and pathological changes similar to those noticed in naturally affected cattle. Cows fed P. sachalinense and V. coignetiae showed no distinct systemic symptoms except transient anorexia and hypothermia.  相似文献   
102.
This study was designed to examine the effects of age and developmental stage of in vitro‐produced bovine embryos on the cell number of the embryos and to investigate the correlation between the cell number and diameter in the embryos. The diameter and cell number in blastocysts and expanded blastocysts collected on days 7–9 after in vitro fertilization (IVF) were examined. Although the diameters of the blastocysts collected on days 7 and 8 after IVF were smaller than those of the expanded blastocysts collected on day 9, the cell number in both types of embryos was similar. The cell numbers of the blastocysts and expanded blastocysts decreased with increasing embryo age. There were positive correlations between the cell number and diameter in bovine embryos at each stage collected on each day after IVF. However, the value of the correlation coefficient in the day‐9 expanded blastocyst group tended to be higher than that in the other groups. These results indicate that the cell number of in vitro‐produced embryos is affected by the embryonic stage and age. The diameter of the embryo may be potentially used for the viability testing of the expanded blastocysts collected on day 9 after IVF.  相似文献   
103.
Peripheral blood samples from dogs infected with Babesia gibsoni were analyzed by a flow cytometer for the percentage of reticulocytes after staining with a membrane-permeable fluorochrome, thiazole orange. Though thiazole orange has been reported to stain human reticulocytes and Plasmodium-infected erythrocytes, number of positive cells determined by the flow cytometry did not include that of erythrocytes infected with Babesia gibsoni. Analysis of 51 samples revealed a correlation coefficient of 0.96 as compared to the conventional determination by light microscopy. Separation of reticulocytes from Babesia gibsoni-infected erythrocytes by flow cytometry with or without the stain remained unresolved.  相似文献   
104.
Yoshito Asano 《Euphytica》1982,31(1):121-128
Summary Meiotic observations in PMCs were made in eight kinds of interspecific hybrids in Lilium. Three hybrids, 6134-S × L. cernuum. L. regale × L. leichtlinii maximowiczii and L. auratum platyphyllum × L. henryi showed respectively the mean chromosome association frequencies of 1.4II, 0.8II and 1.5II per cell at MI which were the lowest values hitherto reported in Lilium hybrids. In L. longiflorum × L. henryi, 33.3° of the cells had 1 or 2 multivalents of three to five chromosomes in addition to uni- and bivalents. 12° bivalents and 12 univalents were invariably observed in the triploid hybrid L. longiflorum × L. cernuum. The hybrids between the species belonging to the different sections of the genus generally showed high pollen sterility, with some exceptions. A more or less remote genomic homology was found between the different sections in Lilium.  相似文献   
105.
106.
Electrolyzed anodic NaCl solutions [EW+], prepared by the electrolysis of 0.1% NaCl, have been shown to instantly inactivate most pathogens that cause food-borne disease. Elimination of food-borne pathogens does not necessarily guarantee food safety because enterotoxins produced by pathogens may remain active. We have tested whether EW+ can inactivate Staphylococcal enterotoxin A (SEA), one of the major enterotoxins responsible for food poisoning. Fixed quantities of SEA were mixed with increasing molar ratios of EW+, and SEA was evaluated by reversed-phase passive latex agglutination (RPLA) test, immunoassay, native polyacrylamide gel electrophoresis (PAGE), and amino acid analysis after 30 min incubations. Exposure of 70 ng, or 2.6 pmol, of SEA in 25 microL of PBS to a 10-fold volume of EW+, or ca. 64.6 x 10(3)-fold molar excess of HOCl in EW+, caused a loss of immuno-reactivity between SEA and a specific anti-SEA antibody. Native PAGE indicated that EW+ caused fragmentation of SEA, and amino acid analysis indicated a loss in amino acid content, in particular Met, Tyr, Ile, Asn, and Asp. Staphylococcal enterotoxin-A excreted into culture broth was also inactivated by exposure to an excess molar ratio of EW+. Thus, EW+ may be a useful management tool to ensure food hygiene by food processing industries.  相似文献   
107.
The tastes of several bitter amino acids and their gamma-glutamyl derivatives were compared. The bitterness of Phe, Val, Leu, and His was reduced, sourness was produced, and preferences were increased by gamma-glutamylization. Because the effect of gamma-glutamylization of bitter amino acids was most obvious for Phe, which is an atypical bitter amino acid, an enzymatic method for the synthesis of gamma-glutamylphenylalanine (gamma-Glu-Phe) involving bacterial gamma-glutamyltranspeptidase was developed. The optimum reaction conditions were 200 mM Gln, 200 mM Phe, and 0.5 unit/mL GGT, pH 10.4. After 1.5-h of incubation at 37 degrees C, 140 mM gamma-Glu-Phe was obtained, the yield being 70%. gamma-Glu-Phe was purified on a Dowex 1x8 column and then identified by NMR.  相似文献   
108.
The hydrogen-bonding structure of water-ethanol in whiskey was examined on the basis of (1)H NMR chemical shifts of the OH of water and ethanol. Phenolic acids and aldehydes (gallic, vanillic, and syringic acids; vanillin and syringaldehyde) exhibited their structure-making effects regardless of the presence or absence of 0.1 or 0.2 mol dm(-3) acetic acid. The OH-proton chemical shifts were measured for 32 malt whiskey samples of a distillery, aged for 0-23 years in five different types of casks. The OH-proton chemical shift values of the whiskies shifted toward the lower field in proportion to their contents of total phenols. It can be concluded that the strength of the hydrogen bonding in aged whiskies is directly predominated by acidic and phenolic components gained in oak wood casks and not dependent on just the aging time.  相似文献   
109.
ABSTRACT

Following the Fukushima Daiichi Nuclear Power Plant accident of 2011, the potential for radiocesium transfer from contaminated soils, such as Andosols, to agricultural crops became a significant concern. Andosols account for up to 70% of paddy soils in the northern and northwest areas of Tochigi Prefecture, where the radiocesium concentration is 1000 Bq kg?1 or greater in the soil of some fields. The present study was carried out in order to determine the phytoavailability of radiocesium in Andosols by comparing it with that of gray lowland soils in the first 3 years following the accident. The transfer factor (TF) tended to be higher in Andosols than in gray lowland soils, leading to higher radiocesium concentrations in brown rice grown in Andosols. The exchangeable potassium (Ex-K2O) in Andosols was highly and negatively correlated with TF, followed by clay. The Ex-K2O value was positively correlated with the clay/total carbon (T-C) value, suggesting that a high T–C ratio could weaken K2O adsorption on clay mineral sites; hence, the low clay/T-C values can partially explain the relatively large TF values of Andosols. Samples with Ex-K2O contents less than 200 mg kg?1 and with low clay/T-C values showed striking decreases in TF values from 2011 to 2012. However, the decrease from 2012 to 2013 was quite small; radiocesium in these samples was potentially available for rice uptake for a long time, likely due to the reversible adsorption and fixation characteristics of allophane. Most gray lowland soil samples showed very low TF values over the 3 years of the study, except for those with TF values greater than 0.1 due to low Ex-K2O and clay contents; the geometric mean (GM) value of TF was below 0.01 in 2012. The extraction of exchangeable radiocesium (Ex-Cs) with a 1 mol L?1 ammonium acetate solution may not be an appropriate method for explaining the variability in radiocesium TF in Andosols. This is because the Ex-Cs value was significantly correlated with Ex-K2O in Andosols, but not in gray lowland soils, indicating that Ex-K2O explained this variability in relation to Ex-Cs.  相似文献   
110.
The behavior of histamine in fish sauce making was investigated using fresh and spoiled fish with or without histidine added during fermentation. The histamine content in the 2% histidine added fresh fish mixture did not change significantly even after a lapse of 4 months incubation. However, when histidine was added to spoiled fish, the histamine content rose to a high level but decreased continuously with incubation time. This decrease may suggest the presence of histamine-decomposing bacteria in the samples. Eight of the 10 commercial fish sauces analyzed contained histamine levels below the "decomposition level" of 50 mg/kg set by the FDA. The increase in histamine at the initial stage and the decrease in histidine might suggest that histidine was converted to histamine by a microorganism possessing the enzyme histidine decarboxylase.  相似文献   
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