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1.
To facilitate the control of progressive atrophic rhinitis (PAR) of swine caused by toxigenic Pasteurella multocida, an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization test (NT) have recently been developed to detect antibodies against the P. multocida dermonecrotic toxin (PmDNT). However, the NT is a cumbersome and time-consuming technique. To overcome these drawbacks, we developed an indirect ELISA, using recombinant PmDNT expressed in Escherichia coli, for the detection of antibodies to PmDNT in serum samples from pigs. The practical usefulness of this ELISA was compared with the NT using serum samples obtained from experimentally infected and naturally infected pigs. In the pigs experimentally inoculated with vaccine including PmDNT toxoid, the ELISA and neutralization antibodies were detected at almost the same time, and a good correlation was demonstrated between both tests (P<0.01, R(2)=0.807). Therefore, the ELISA can be used to evaluate the immune reaction of pigs after vaccination with P. multocida toxoid. In a survey conducted on a field herd with a history of clinical AR, the seropositivity by ELISA in pigs of age 4.5-6 months was increased even though the NT was negative, and the correlation was low between the results obtained with the two tests (P<0.01, R(2)=0.38). Therefore, the results indicated that this ELISA might be a useful alternative to the NT currently used to detect the antibody to PmDNT after vaccination or infection with P. multocida.  相似文献   
2.
An analysis of ionizing radiation-induced damage in peripheral lymphocytes has been employed to predict the prognosis of radiotherapy in terms of toxicity in normal tissues. Therefore, understanding the sensitivity of lymphocytes to high linear energy transfer (LET)-charged particles would be indispensable for utilizing charged particle therapy in veterinary medicine. However, the availability of such information is very limited. This study aimed to compare the radiosensitivity of feline T lymphocytes to gamma-rays (0.2 keV/microm) and 4 different types of charged particles with LET values ranging from 2.8 to 114 keV/microm. It was observed that the relative biological effectiveness, inactivation cross-section, and isodose-induced apoptosis increased in an LET-dependent manner. On the other hand, no difference in apoptosis frequency was observed in the cells exposed to an isosurvival dose of all the radiation types tested. This is the first study that demonstrates the LET dependence of cell killing and apoptosis induction in feline T lymphocytes. Our results suggest that lymphocytes can be effectively used to predict the prognosis of charged-particle therapy in cat patients.  相似文献   
3.
耐热优质黄瓜新品种夏盛的选育   总被引:3,自引:0,他引:3  
利用耐热、抗病的雌性系GE作母本,优质的绿宝选1作父本配制而成的一代杂种——夏盛,夏季栽培从播种到始收33天,一般667m2产2500kg,高产的可达3500kg,耐热性强,抗病毒病(CMV)和中抗疫病。果实圆筒形,长21.5cm,横径4.7cm,肉厚2.8cm,质脆,皮色深绿有光泽,适于华南地区夏秋露地栽培  相似文献   
4.
Paddy and Water Environment - Rice paddy fields are important habitat for many dragonfly species. In Japan, populations of dragonflies inhabiting rice paddies, in particular Sympetrum (Odonata:...  相似文献   
5.
RAPD analysis was applied to reveal the genetic diversities of 4 speciesof subg. Lithocerasus within the genus Prunus using 40accessions representing the subgenera Prunophora, Amygdalus,Lithocerasus and Cerasus. The accession of subg. Lithocerasus are phenotypically similar to members of subgenus Cerasus but different with them in interspecific crossing tests and isozymeprofiles. Two major clusters, `Prunophora and Amygdalus group' and `Cerasus group' were constructed in the phenogram. We revealthat the examined 4 species of subg. Lithocerasus species; P.tomentosa Thunb., P. japonica Thunb., P. glandulosa Thunb.and P. besseyi Bailey, were genetically closer to the members ofsubgenera Prunophora and Amygdalus than to subg. Cerasus.  相似文献   
6.
(pp. 17–24)
A trial calculation was performed of the environmental nitrogen-assimilation capacity and the amount of nitrogen input based on various statistical data, which were compiled from each city, town and village in Hokkaido prefecture. The relationship between the excess quantity of nitrogen, after nitrogen input, and the environmental nitrogen-assimilation capacity and the nitrate-nitrogen concentration of the groundwater was considered.
Environmental nitrogen-assimilation capacity = nitrogen output by the crops + acceptable level of residual nitrate in the soil profile.*
*It is calculated by the amount of nitrate precipitation evapotranspiration ×10 mg L−1.
  • 1) 

    The average value of the environmental nitrogen-assimilation capacity in Hokkaido Prefecture was observed to be 183 kg ha−1. The maximum and minimum values of the environmental nitrogen-assimilation capacity were 308 kg ha−1 and 94 kg ha−1, respectively. When the average value of the environmental nitrogen-assimilation capacity with respect to main agricultural land use was compared across municipalities, it was largely in the following order · grassland (218 kg ha−1), upland (169 kg ha−1), and paddy land (157 kg ha−1).

      相似文献   
7.
8.
A method for HPLC determination of phycocyanin in phytoplankton samples using gelchromatography with a fluorescence detector was developed to examine the use of phycocyanin as an index of the appearance and progress of cyanobacterial blooms in highly eutrophic lake. At least two types of phycocyanin with different molecular weights, each spectroscopically different from phycoerythrin and allophycocyanin, were found in natural phytoplankton samples. Changes in phycocyanin concentrations were clearly coupled to changes in chlorophyll-a concentrations during June to October while cyanobacterial blooms were occurring. The chlorophyll-a to phycocyanin relationship was linear at chlorophyll-a concentrations of less than 250 μg L?1. The relationship between cyanobacterial carbon and phycocyanin concentration was also linear, suggesting that phycocyanin content may be a useful index of cyanobacterial biomass in highly eutrophic lakes where large cyanobacterial blooms occur.  相似文献   
9.
The cell-associated adsorption of thorium or uranium from the solution containing each metal only at pH 3.50 using various microorganisms was examined. Among the species tested, high thorium adsorption abilities were exhibited by strains of the gram-positive bacteria Arthrobacter nicotianae IAM12342, Bacillus megaterium IAM1166, B. Subtilis IAM1026, Micrococcus luteus IAM1056, Rhodococcus erythropolis IAM1399, and Streptomyces levoris HUT6156. And high uranium adsorption abilities were found in some gram-positive bacterial strains S. albus HUT6047, S. levoris HUT6156, and A. nicotianae IAM12342. Among these highly efficient thorium and uranium adsorbing microorganisms, S. levoris, which could adsorb the largest amount of uranium from the aqueous solution at pH 3.50, could adsorb about 383 mol thorium and 390 mol uranium per gram dry weight of microbial cells from the solution containing thorium or uranium at pH 3.50. The amount and time course of thorium adsorbed were almost unaffected by co-existing uranium; however, the adsorption of thorium was faster when carried out after the adsorption of uranium. Thorium adsorption also became faster when uranium was added after thorium adsorption. The effect of pH on thorium adsorption was also discussed.  相似文献   
10.
We examined nasal swab and lung homogenate samples collected from pigs experimentally and naturally infected with Mycoplasma hyopneumoniae for the detection of M. hyopneumoniae by the nested PCR (nPCR) and culture methods. In the 23 experimentally infected pigs, M. hyopneumoniae was commonly detected in nasal swabs by the nPCR and culture methods at 4 weeks after inoculation, and there was a significant correlation (P<0.01) between the titers of viable organisms in nasal swabs and in lung homogenates in the experimentally inoculated pigs. In the naturally infected pigs, on the other hand, discrepancies in detection were found between nasal swab and lung homogenate samples in 17 of 36 cases, although the presence of gross lung lesions correlated relatively well with the detection of organisms from the samples. Our results indicated that the diagnosis of mycoplasmal pneumonia by nPCR in individual pigs with nasal swabs is reliable under these experimental conditions. At present, nPCR with nasal swabs should only be used for monitoring the disease status at the herd level under field conditions.  相似文献   
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