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排序方式: 共有310条查询结果,搜索用时 15 毫秒
61.
62.
We evaluated a recently developed live vaccine candidate for fowl typhoid (FT)-JOL916, a lon/cpxR mutant of Salmonella Gallinarum (SG)-by comparing its safety and efficacy with that of the well-known rough mutant strain SG9R vaccine in 6-wk-old Hy-Line hens. Forty-five chickens were divided into three groups of 15 chickens each. The chickens were then intramuscularly inoculated with 2 x 10(7) colony-forming units (CFUs) of JOL916 (JOL916 group), 2 x 10(7) CFUs of SG9R (SG9R group), or phosphate-buffered saline (control group). After vaccination, no clinical symptoms were observed in any of the groups. No differences in body weight increase were detected among the three groups postvaccination. A cellular immune response was observed at 2 wk postvaccination (wpv) in the JOL916 group with the peripheral lymphocyte proliferation assay, whereas no response was detected in the SG9R group. Elevation of SG antigen-specific plasma immunoglobulin was observed 2 and 3 wpv in the JOL916 and SG9R vaccine groups, respectively. After virulent challenge on day 25 postvaccination, 0, 1, and 15 chickens in the JOL916 group, SG9R group, and control group, respectively, died by 12 days postchallenge; the death rate of the SG9R vaccine group was statistically similar to that of the JOL916 group. Postmortem examination revealed that the JOL916 vaccine offered more efficient protection than the SG9R vaccine, with significantly decreased hepatic necrotic foci scores, splenic enlargement scores, necrotic foci scores, and recovery of the challenge strain from the spleen. Vaccination with JOL916 appears to be safe and offers better protection than SG9R against FT in chickens. 相似文献
63.
Keiko Uchida Susumu Takamatsu Sanae Matsuda Kazuhiro So Yukio Sato 《Journal of General Plant Pathology》2009,75(2):92-100
In 2002, a powdery mildew with catenate conidia lacking fibrosin bodies was found on cucumber in a greenhouse in Kanagawa
Prefecture, Japan. Morphological observation revealed that the fungus belongs to Oidium subgenus Reticuloidium, anamorph of the genus Golovinomyces. Molecular phylogenetic analyses of the nucleotide sequences of the rDNA ITS regions and D1/D2 domains of the 28S rDNA indicated
that the fungus belongs to the clade of G. orontii with other Golovinomyces fungi from a wide range of host plants, suggesting that the fungus was newly transported from abroad. Because there has been
no prior report of cucumber powdery mildew caused by Reticuloidium, further research on the physiology, epidemiology, control and resistant cucumber varieties is required. 相似文献
64.
Matsuda Y Ikeda H Moriura N Tanaka N Shimizu K Oichi W Nonomura T Kakutani K Kusakari S Higashi K Toyoda H 《Phytopathology》2006,96(9):967-974
ABSTRACT In an attempt to physically protect greenhouse tomato plants from the powdery mildew fungus Oidium neolycopersici, we developed a new electrostatic spore precipitator in which a copper wire conductor is linked to an electrostatic generator and covered with a transparent acrylic cylinder (insulator). The conductor was negatively charged by the generator, and the electrostatic field created by the conductor was used to dielectrically polarize the insulator cylinder. The dielectrically polarized cylinder also produced an electrostatic force without a spark discharge. This force was directly proportional to the potential applied to the conductor and was used to attract conidia of the pathogen. The efficacy of this spore precipitator in protecting hydroponically cultured tomato plants from powdery mildew was evaluated in the greenhouse. The hydroponic culture troughs were covered with a cubic frame installed with the spore precipitator, and the disease progress on precipitator-guarded and unguarded seedlings was traced after the conidia were disseminated mechanically from inoculum on tomato plants. Seedlings in the guarded troughs remained uninfected during the entire experiment, in spite of rapid spread of the disease to all leaves of the unguarded seedlings. 相似文献
65.
Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzymes, including AluI and MboI, of the 1,500 bp fragments of rDNA amplified by polymerase chain reaction did not discriminate the genomic variations among the eight strains of T equigenitalis. Thus, pulsed-field gel electrophoresis was shown to discriminate these eight organisms better than random amplified polymorphic DNA analysis, while amplified rDNA restriction analysis was found to be unsuitable for subtyping T equigenitalis. 相似文献
66.
Mast cell associated-immune resistance against ticks 总被引:1,自引:0,他引:1
67.
Numbers of eosinophils in the bovine oviduct and uterus were determined during the oestrous cycle. The eosinophil numbers in the oviduct (ampulla and isthmus) and horn of the uterus during oestrus were significantly higher than during dioestrus. The number of eosinophils in the uterine cervix was lower than in the uterine horn for all stages of the oestrous cycle. In the oviduct, eosinophils accumulated in the lamina propria of the tunica mucosa, in the tunica muscularis and in the connective tissue of the tunica serosa. In the uterus, they were concentrated mainly in the upper parts of the stroma in the endometrium. Degranulation of eosinophils was observed during oestrus when they increased in number in the oviduct and uterus. 相似文献
68.
H. Matsuda 《Wood Science and Technology》1987,21(1):75-88
Summary Preparation and utilization of esterified woods bearing carboxyl groups are reviewed. The esterified woods are prepared by the addition reactions of wood with dicarboxylic acid anhydrides in the presence or absence of a solvent such as dimethylformamide. The reactions without solvent are industrially advantageous and can give esterified woods with a wide range of monoester contents. The esterified woods can be molded into sheets by hot pressing. By addition reactions of the esterified woods with epoxide, or epoxide and anhydride at high temperatures, epoxide-adducted esterified woods and oligoesterified woods are obtained. These can also be molded by hot pressing. The addition of epoxide to esterified woods results in an improvement in moisture resistance of the molded sheets. When esterified woods are subjected to crosslinking reactions with bisepoxide both at high temperatures and under high pressures, the wood components plasticize to give reddish brown, yellowish brown, or blackish brown crosslinked wood boards whose surfaces are smooth, glossy, and plastic-like. Among the plastic-like crosslinked wood boards, the phthalic anhydride-based board shows the best physical properties. Especially, this board exhibits very high compressive strength and water resistance. 相似文献
69.
Tadashi Oikawa Toshiya Matsui Yasunori Matsuda Teruko Takayama Hitoshi Niinuma Yasuyo Nishida Kazuo Hoshi Mitsuyoshi Yatagai 《Journal of Wood Science》2006,52(2):140-146
Volatile organic compounds (VOCs) from wood and their effects on artifacts are of intense interest to museum staff who must
strictly manage the preservation environment. In this study, the causal substances of deterioration were inferred by comparison
with laser Raman (LR) spectra of deterioration products. The artifact samples were deteriorated using VOCs from woods (WV
test), and using specific substances that occur in wood VOCs (SV test). The deteriorated samples were analyzed by LR spectroscopy
and the results of the WV and SV tests were compared.
Hinokitiol and acetic acid were found to be two of the main causal substances of deterioration in western red cedar. Deterioration
of iron and copper by spruce did not appear to be caused by acetic acid, as is generally assumed, but by some other unknown
compound(s). Sensitivity to wood-based VOC components depended on the type of artifact. In western red cedar, mitsudasou (litharge) was very sensitive to acetic acid, while other artifacts were sensitive to hinokitiol. The LR method used in this
study is very useful for the inference of causal substances of deterioration based on the detection of small amounts of deteriorated
products such as those generated by deterioration due to wood VOCs.
Part of this article was presented at the 25th Annual Meeting of the Japan Society for the Conservation of Cultural Property,
Kyoto, June 2003 相似文献
70.
A screening tool for vulnerability assessment of pesticide leaching to groundwater for the islands of Hawaii, USA 总被引:1,自引:0,他引:1
This paper describes an updated version of a screening tool for groundwater vulnerability assessment to evaluate pesticide leaching to groundwater, based on a revised version of the attenuation factor. The tool has been implemented in a geographical information system (GIS) covering the major islands of the state of Hawaii, USA. The Hawaii Department of Agriculture currently uses the tool in their pesticide evaluation process as a first-tier screening tool. The basic soil properties and pesticide properties necessary to compute the index, and estimates of their uncertainty, are included in the GIS. Uncertainties in soil and pesticide properties are accounted for using first-order uncertainty analysis. Classifications of pesticides as 'likely', 'uncertain' or 'unlikely' to leach are made on the basis of the uncertainty and a comparison of the revised attenuation factor with values and uncertainties of two reference chemicals. The reference chemicals represent what are considered to be a 'leachable' and a 'non-leachable' pesticide under Hawaii conditions. It is concluded that the tool is suitable for screening new and already used pesticides for the islands of Hawaii. However, the tool is associated with uncertainties that are not accounted for, so a conservative approach with respect to interpretation of the results and selection of pesticide parameters used in the tool is recommended. 相似文献