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排序方式: 共有1371条查询结果,搜索用时 0 毫秒
101.
102.
103.
T Sakai K Takahashi S Hisasue M Horimoto T Takizawa 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(1):121-127
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
104.
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
105.
106.
H Kurazono K Shimozawa G Sakaguchi M Takahashi T Shimizu H Kondo 《Research in veterinary science》1985,38(1):104-108
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
107.
108.
Deep-seeding tolerance, the emergence of seedlings from deep seeded conditions, is involved in stand establishment in semi-arid
regions, where the soil surface is too dry for seed germination. Genes determining deep-seeding tolerance in barley were mapped
using two doubled haploid populations derived from the following crosses: Harrington × TR306 (H/T)and Step toe × Morex (S/M).
Significant quantitative trait loci (QTLs) for deep-seeding tolerance were found in each population. Two QTL sex plained 40%
of the phenotypic variation in the H/T population and one QTL (S/M) 8% of the total phenotypic variance. Multiple QTLs accounting
for coleoptile length and first internode length were detected in both populations. In the H/T population, there were coincident
QTLs for deep-seeding tolerance, coleoptile length and first internode length on the long arm of chromosome 5H. These QTLs
correspond with previously reported QTLs for abscisic acid and gibberellic acid response. QTL coincidence may be due to the
pleiotropic effects of alleles at a single locus. This information may be useful for breeding programs manipulating morphological
and physiological traits in order to develop varieties for semi-arid regions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
109.
Digestion of carp myofibrils at 30 degrees C in 0.5 M KCl medium with calcium ion generated unique 135 kDa heavy meromyosin (HMM). The HMM was not produced when digested at 10 degrees C. A further digestion of the 135 kD HMM isolated in the absence of calcium ion generated uniquely short subfragment-2 (S-2) with a size of 40 kDa (40 kDa S-2) together with subfragment-1 (S-1). The 40 kDa S-2 was identified by N- and C-end sequencing, and demonstrated to locate the amino end of the rod portion. The unfolding temperature for the 40 kDa S-2 was around 52 degrees C as studied by circular dichroism measurement. The same unfolding peak was also detected with the intact rod together with a large unfolding peak at around 36 degrees C coming from the rest of the rod portion, light meromyosin. The unfolding peak for the 40 kDa S-2 in myosin was a little lower (48 degrees C) than that in free form, suggesting the involvement of the head portion in the stability of the 40 kDa S-2 in the structure. 相似文献
110.
Phthalate esters have become widespread contaminants in the aquatic environment, because of their extensive use as non-reactive plasticizers. There is, however, little accurate data on their solubility, transportation, and distribution in the aquatic environment. In this work, we have investigated the influence of humic acid on the water solubility of di-(2-ethylhexyl)phthalate (DEHP), one of the most frequently used phthalate esters in the laboratory studies for DEHP. We have also studied the solid–water distribution of DEHP in the presence of humic acid and particulate matter (activated carbon, ferrihydrite, and kaolinite) to simulate their distribution in a natural aquifer (ternary system). The results show that the water solubility of DEHP can be significantly increased by humic acid. The shape K eq value, the binding constant of DEHP between water and humic acid at equilibrium, was obtained by fitting experimental data for each humic acid. The shape K eq values in the ternary system apparently decreased in the order of ferrihydrite ≤ kaolinite ≈ octanol/water partition activated carbon systems. This result shows that the increase in the hydrophobicity of HA remaining in the solution will lead to the apparent increase of shape K eq in the system since more hydrophilic solid sorbs relatively more hydrophilic HA molecule. The solid–water partition coefficient (shape K W-P ) for DEHP in the environment estimated from this study is consistent with those reported based on the experiments for natural samples. Quantitative values obtained in this study, such as K'ow, shape K eq, and shape K W-P , can be useful for estimating the behavior of DEHP. 相似文献