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81.
Paddy and Water Environment - In this article, we examined the value of the traditional Japanese flood control measure that uses a discontinuous levee (kasumitei). By avoiding the use of...  相似文献   
82.
ABSTRACT:   The effect of salt concentration on the thermal denaturation profile of myosin in walleye pollack and carp myofibrils was compared by studying the subfragment-1 (S-1) and rod denaturation rates upon heating. Species-specific denaturation mode observed at 0.1 M KCl was no longer detected when samples were heated above 0.5 M KCl, where S-1 and rod denaturation rates were identical to each other. As the heating of the chymotryptic digest of myofibril formed practically no rod aggregates, S-1 denaturation in a form of myosin was the rate limiting step for rod aggregate formation. As the aggregate formation by rod was remarkably suppressed by lowering the temperature, the free movement of myosin tail upon heating was suggested to play an important role in the rod aggregate formation in a high salt medium.  相似文献   
83.

Although fish roes (or the egg-laden ovary) are seafood products with high nutritional value and are considered abundant in vitamins including vitamin B12, nevertheless, the detailed properties of vitamin B12 have not been fully elucidated in fish roe products. Vitamin B12 content was determined using C18-reversed-phase high-performance liquid chromatography after purification of samples from immunoaffinity columns. Salmon egg-laden ovary products (sujiko), salmon roe products (ikura), dried mullet roe products (bottarga), and white sturgeon roe products (caviar) were found to contain substantial levels of vitamin B12 (more than approximately 15 µg/100 g wet weight). Interestingly, high levels of vitamin B12 per 100 g wet weight have been measured in pollack roe products (tarako) and flying fish roe products (tobiko). Liquid chromatography–electrospray-ionization/tandem mass spectrometry analysis revealed that vitamin B12 was the predominant corrinoid in the evaluated fish roe products examined, while no inactive corrinoid compounds were identified. These results suggest that commercially available fish roe products could be an important source of vitamin B12 for use as a dietary product for humans.

  相似文献   
84.
From 1982 to 1987 a total of 4,371 dairy cattle in Saitama Prefecture, were examined for levels of hemagglutination inhibition (HI) antibody to Japanese encephalitis virus (JEV) and the correlation with meteorological factors and an antibody positive rate was studied. Positivity rates of HI antibody from July to October each year (Yi) ranged from 58.8 to 88.0% with a considerable annual variation. Simple regression analysis of Yi with the comparative meteorological value (Xi) was determined from mean temperatures (Ti, j-1), rainfalls (Ri, j-1) for 10-day-periods each, and the number of days showing 25 degrees C or above (ti, j-1) from June to September, which yielded a correlation coefficient of 0.8147 (p less than 0.05) and an equation for estimated HI antibody positivity rate: Yi = -0.04Xi+79.9 (p less than 0.05). Multiple regression analysis with the power values of three meteorological parameters as independent variables and Yi as the dependent variable, showed a multiple correlation coefficient of 0.987 (p less than 0.05) and a multiple regression equation: Yi = -3991T1/13-0.0035R-12+1978t1/9+4187 (p less than 0.05), giving estimated positivity rates almost equal to the values from the observations. Therefore, a predictive equation was formulated reflecting positive and negative correlations of sero-positivity with the temperature and the precipitation, respectively.  相似文献   
85.
Cross-protection between Haemophilus parasuis serovars 2 and 5 was examined in pigs using a bacterin based vaccine, and subsequently the safety and efficacy of a bivalent vaccine were evaluated. Upon intratracheal challenge of a serovar 2 or 5 strain, pigs immunized with a monovalent vaccine were protected against challenge with a homologous serovar strain, but not with a heterologous serovar strain. Immunization with a bivalent vaccine containing both serovars 2 and 5 bacterins conferred protection in pigs against lethal challenge with each of the serovar strains. A total of 86 pigs from two SPF herds were injected with the bivalent vaccine intramuscularly twice at a four-week interval. No adverse reactions following the vaccination were observed. On day 7 after the second vaccination, vaccinated and non-vaccinated control pigs from herd A were transferred to herd B, where Glasser's disease had broken out. Pigs in the control group developed clinical signs of the disease, and 6 of 8 (75%) pigs died until slaughter, in contrast with only 4 of 46 (9%) pigs in the vaccinated group. In herd C, where there was no outbreak of Glasser's disease, complement fixation antibody titer was raised only in the vaccinated group. A challenge experiment on days 20 and 79 after the second vaccination showed that only the vaccinated pigs were protected. From these findings, the safety and efficacy of the bivalent vaccine were confirmed under laboratory and field conditions.  相似文献   
86.
We examined an epileptic focus by electroencephalography (EEG) by using an international 10-20 electrode system in 11 Shetland sheep dogs affected with familial idiopathic epilepsy. We also performed an evaluation of the amino acids in the cerebrospinal fluid (CSF) and a pathologic examination of the brains of 8 dogs that died from status epilepticus. Continuous electroencephalography demonstrated that an epileptic focus was initially detected in the frontal lobe, particularly the internal area, and that paroxysmal foci developed diffusely in other lobes of affected dogs with recurrent convulsions. The EEG analyses indicated spike and sharp wave complexes, which were considered to be paroxysmal discharges. An increased value for glutamate or aspartate was found in the CSF of some epileptic dogs. Histologically, acute neuronal necrosis and astrocytosis were distributed predominantly in the cingulate cortex and internal area of frontal cortex, less frequently in other areas of the cerebrum. The results of this study suggest that, initially, the dogs have an epileptic focus in the frontal lobe, and that the focus extends gradually to other areas of the cerebrum. Based on the distribution of neuronal necrosis and astrocytosis, acute neuronal damage may be related to the superexcitation of neurons following epilepsy.  相似文献   
87.
Salinity is at present one of the most serious environmental problems influencing crop growth. It has been extensively demonstrated that salinity affects several physiological processes in the plant, including the plant–water relations of most salt-sensitive crops species. In this study, the effects of salinity on the plant–water relations of kidney bean ( Phaseolus vulgaris L.) and the possibility that foliarly applied glycinebetaine improves these water relations are examined. Kidney bean plants were grown in a greenhouse and treated with 0, 30, 50 and 100 m M NaCl, combined with 0, 10 and 30 m M glycinebetaine in foliar applications. Increased salinity levels decreased stomatal conductance, photosynthetic rate, transpiration and leaf relative water content in the 30, 50 and 100 m M treatments relative to the control treatment. Glycinebetaine applications of 10 m M increased stomatal conductance at 50 m M NaCl, ameliorating significantly the effect of salinity on water relations through increases in the leaf relative water content. At 100 m M NaCl, 30 m M glycinebetaine applications in particular contributed to osmotic stress, and had an adverse effect on plants. Our experiment suggests that glycinebetaine can be used as an alternative treatment to reduce the effects of salt stress on the water relations of salt-sensitive plants, but only to limited salinity levels. Furthermore, the improvement in the water status of kidney beans was dose dependent, suggesting that the concentration of glycinebetaine essential for the survival of salt-sensitive plants is species specific and must be determined individually for each plant species.  相似文献   
88.
89.
Fifty to 100 per cent of about 8000 penned pheasants raised on a farm in Hiroshima Prefecture died annually for three years. Deaths were ascribed to type C botulism. Vaccination of four groups of pheasants with partially purified C1 toxoid effectively protected them against type C botulism. The protective efficacy of the toxoid was emphasised by the relatively high susceptibility of the pheasant to C1 toxin.  相似文献   
90.
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