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91.
In order to distinguish the two eel species Anguilla japonica and A. anguilla irrespective of unprocessed and processed samples, a quick, convenient method using polymerase chain reaction (PCR) with a species-specific primer was established. The comparison of partial sequences of the mitochondrial 16S ribosomal RNA gene between A. japonica and A. anguilla facilitated designing of a primer pair common to both A. japonica and A. anguilla and a primer specific to A. japonica. PCR was carried out with the three primers for total 110 specimens of A. japonica and A. anguilla. PCR products with the species-specific primer showed two bands for A. japonica and one band for A. anguilla in an agarose gel electrophoresis. This analytical procedure required only a short period and is more convenient than PCR-restriction fragment length polymorphism, one of the standard methods employed for fish species identification.  相似文献   
92.
Mouse BALB/3T3-A31-1-1 (A31) cells are non-permissive to bovine herpes virus-1 (BHV-1) but permissive to pseudorabies virus (PrV). The promoter activity of the immediate early gene of BHV-1 (BICP4) was very weak when compared with that of PrV in A31 cells. Infectious BHV-1 genomic DNA co-transfected into A31 cells with plasmids expressing BICP4 and BICP0 by a strong promoter failed to yield any progeny virus. Growth of BHV-1 in non-permissible A31 cells is restricted in many phases of the growth. The fact that expression of BICP4 and/or BICP0 in A31 cells does not improve the yield of progeny virus from infectious BHV-1 genomic DNA suggests that some more growth restrictions exist beyond the expression of BHV-1 immediate early proteins.  相似文献   
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An outbreak of congenital hydranencephaly and cerebellar hypoplasia occurred between November 1985 and May 1986 in Miyazaki, South Kyushu, Japan. Seventy-three calves had nervous signs of varying severity such as inability to stand, locomotor difficulties, defective vision and difficulty in sucking. At necropsy, 62 calves had macroscopic lesions in the central nervous system: hydranencephaly accompanied by cerebellar hypoplasia in 47; hydranencephaly alone in eight; and dilatation of the lateral ventricle in seven; none had arthrogryposis. Microscopically, all 62 cases involved various degrees of hypoplasia of neural components, such as total or partial thinning of the cerebral or cerebellar laminae. Heterotopia, such as abnormal islands of granule cells or Purkinje cells was also observed. Fourteen of these animals had other lesions such as non-purulent encephalitis, focal gliosis, neuronal degeneration, calcification or pseudocalcification, and cholesterol deposits, activation of vascular endothelial cells and haemorrhage. From the findings, these cases were considered to represent mainly hypoplasia of nerve tissue due to infection with a virus different from Akabane virus.  相似文献   
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ABSTRACT:   The effects of shrimp head protein hydrolysate (SHPH) from three species of shrimp (northern pink shrimp [ Pandalus eous ], endeavour shrimp [ Metapenaeus endeavouri ], black tiger shrimp [ Penaeus monodon ]) on gel forming ability and protein denaturation of lizardfish surimi during frozen storage at −25°C were evaluated. The quality of lizardfish surimi with 5% (dried matter) of any of the three SHPH or sodium glutamate (Na-Glu) was examined in terms of gel strength, whiteness, Ca-ATPase activity and the amount of unfrozen water, comparing with those of surimi without additive as the control. The residual Ca-ATPase activity and gel strength of surimi with SHPH were higher than those of the control throughout 180 days of frozen storage, regardless of shrimp species. The highest effect was found in surimi with Na-Glu. The gel strength and Ca-ATPase activity found a high positive correlation. The addition of SHPH to surimi also increased the amount of unfrozen water by approximately 1.29–1.36 fold higher than the control, however kamaboko gels of the control was significantly whiter. From these results, freeze-induced denaturation of lizardfish muscle protein could be lessened by the addition of SHPH, resulting in a high gel strength and Ca-ATPase activity.  相似文献   
98.
Abstract

Humic acids (HAs) obtained from four different soils by sequential extraction with pyrophosphate solutions at different pH values (i.e. at pH 3, 5, 7, 9, 11, and 13), were examined by ultraviolet and visible (UV-VIS) spectroscopy and elemental analysis. UV-VIS spectra from 230 to 700 nm were measured, and absorbance coefficients of 1% humic acid solutions at 600 nm (E 1% 600) and Δlog K were calculated. The shape of the spectra of humic acids depended on the soil types rather than on the pH values. The (E 1% 600) values were higher in the neutral region, and lower in the alkaline region, for each pH value they decreased in the following order: buried Andosol > Andosol > Histosol ≧ Cambisol. The Δlog K values for each pH value were higher in the following order: Histosol> Cambisol > buried Andosol≧Andosol. Although the linear correlation was found to be significant between the E 1% 600 and Δlog K values, the relation between these optical properties and pH values differed among the soil types. However, in the neutral region, the higher E 1% 600 values of humic acids from buried Andosol and Andosol and the lower Δlog K values of humic acids from Cambisol and Histosol suggest that the humification degree was higher in the neutral region. Data of elemental composition and atomic ratios were obtained for each humic acid. The H/C ratios in the four soils increased gradually with increasing pH values from 5 to 13, and those for each pH value were commonly higher in the following order: Cambisol> Histosol> Andosol> buried Andosol. The O/C and OIH ratios decreased with increasing pH values. The results of the H/C versus O/C diagram suggested that decarboxylated humic acids were extracted at the higher pH values. A highly significant correlation coefficient was obtained between the H/C and OIH ratios (r= ?0.891***). Results showing that the decrease of the pH values corresponded to the order of the humic acids in the correlation curve in the H/C versus O/H diagram suggest that the humic acids with a higher content of unsaturated bonds and a higher degree of oxidation were extracted at the lower pH values within the range from 5 to 13.  相似文献   
99.
A volcanic ash soil consisting of more than 40 layers, of volcanic fallout was studied from the standpoint of humus chemistry. According to soil texture and humic acid type, the soil profile was divided into 3 sections as follows: (1) Upper layers formed since 1779 A.D. Loamy sand. Po or A type. (2) Middle layers formed from 1779 A.D. to 5,540 yr. B.P. Sandy loam, A, A or P type. (3) Lower layers formed from 5,540 yr. B.P. to about 20,000 D.P. Sandy clay, loam or clay loam, A± type. The PQ values in the middle layers were lower than those of the upper and lower layers.

The distribution of carbon and nitrogen contents in the fulvic and humic acid and humin fractions of each layer varied considerably. The CfN ratio of the total humus of each layer tended to increase with the increase in its carbon content. C/N ratios of humic acids in the lower layers were higher than those in the upper and middle layers. C/N ratios of fulvic acid fractions were nearly constant (10-13), for all layers examined, and those of humin fractions ranged from 15 to 20, with one exception of 34.

The amounts of sugars, uronic acids and amino acids in hydrolysates of fulvic acids were more or less same for all samples, and sum of the amounts of carbon in these compounds comprised 30 to 40 percent of fulvic acid carbon. Amino acid nitrogen comprised 72 to 94 percent of fulvic acid nitrogen. Seven amino acids were detected, among which aspartic acid, glutamic acid and glycine were predominant.  相似文献   
100.
An important breeding issue in buckwheat is to increase its resistance to lodging, which can result in the loss of yield and quality of buckwheat foods. We developed the semidwarf buckwheat ‘Kyukei 50’, which has a short plant height and a strong lodging resistance. The internode length of ‘Kyukei 50’ was shorter than that of the summer-sown standard variety ‘HITACHIAKISOBA’. Progeny analysis revealed that the semidwarf trait was dominated by at least one recessive gene. Compared with ‘HITACHIAKISOBA’, in ‘Kyukei 50’, the time of maturation was earlier, and the pre-harvest sprouting resistance was the same, indicating that ‘Kyukei 50’ is suitable for sowing in both spring and summer. ‘Kyukei 50’ exhibits the ‘green flower type’ shattering resistance trait and, therefore, has a thick pedicel; breaking tensile strength is approximately two-fold stronger than that of ‘HITACHIAKISOBA’. The yield of ‘Kyukei 50’ is the same as that of ‘HITACHIAKISOBA’. In addition, the lowest seed height of ‘Kyukei 50’ was >17 cm. These results indicate that the ‘Kyukei 50’ is a promising breeding line for lodging resistance and loss of harvesting machinery.  相似文献   
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