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111.
Four pregnant heifers were immunized by the intramammary route with killed or live Streptococcus agalactiae vaccine, and a 5th heifer was vaccinated by the intramuscular route with killed vaccine. Antibody in the colostrum from vaccinated and non-vaccinated glands was compared. Antibacterial glands was compared. Antibacterial antibody titers of the 4 immunoglobulin classes were determined by indirect fluorescent antibody assay. Although the content of immunoglobulin G1 (IgG1), IgG2, and IgM in the colostrum from the vaccinated glands was not substantially different from the nonvaccinated glands, IgA content was considerably greater in the former. Antibody specific to S agalactiae was isolated from all colostrum samples. The mouse passive protection test and Ouchterlony analysis were used to demonstrate the presence of type-specific antibody to Ia strain used for vaccination. The passive mouse protection test also was useful to compare the protective capacity of specific S agalactiae, type Ia, antibodies of immunoglobulin classes IgG, IgM, and IgA. Increased protective capacity of IgM and IgA over IgG1, on a weight basis, was demonstrated. The present study indicates that S agalactiae preparations, when introduced into the mammary gland, can give rise to local antibody synthesis in the vaccinated glands. 相似文献
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L.K. Cutkomp D. Desaiah E.Y. Cheng E.V. Vea R.B. Koch 《Pesticide biochemistry and physiology》1976,6(3):203-208
American cockroaches injected with sublethal doses of DDT (0.75 μg/roach) at 5-day intervals showed a 40% reduction in oligomycin-sensitive Mg2+ATPase from muscle homogenates, and a 23% reduction of Na+-K+ATPase from nerve cords. Thus, the maximum effect measured occurred with the same enzyme and tissue as determined from in vitro studies. The metabolite, DDE, used at 15 μg per roach, gave no significant change in activity of the ATPase system following injection. In contrast, high single doses of DDT (7.5 μg/roach) and 100 μg DDE and dicofol per roach caused over 30% increase in oligomycin-sensitive Mg2+ATPase of muscle and a 10–15% increase in Na+-K+ATPase of nerve cords measured 24 and 48 hr later. While a similar response was observed for Mg2+ATPase activities in cockroaches that were immobilized, the increase in enzyme activities were much greater than that caused by the pesticides. 相似文献
115.
The phytotoxicity of 2,4-bis(isopropyl)-6-(methylthio)-s-triazine (prometryne) and 2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine (terbutryn) to peas (Pisum sativum L. var. Perfection 3040) was studied. No differences were found when the herbicides were applied to the roots of intact plants in nutrient solution or directly to leaf discs. However, prometryne was much more toxic when uptake was from soil. Absorption and translocation of 14C-labeled prometryne and terbutryn showed that the majority of terbutryn accumulated in the roots, whereas prometryne was uniformly distributed between the roots and the shoot. Thin layer chromatography of extracts from prometryne-treated peas showed that only 20% of the absorbed compound was metabolized to produce one breakdown product. Extracts of terbutryn-treated plants contained three different metabolites. After 120 hr of exposure to terbutryn, about half of the absorbed herbicide was metabolized. The results show that the main factors responsible for the differential toxicity of the herbicides to peas were availability from the soil, translocation pattern and initial detoxication. 相似文献
116.
Hideki Takahashi Ayano Shimizu Tsutomu Arie Syofi Rosmalawati Sumire Fukushima Mari Kikuchi Yasufumi Hikichi Ayami Kanda Akiko Takahashi Akinori Kiba Kohei Ohnishi Yuki Ichinose Fumiko Taguchi Chihiro Yasuda Motoichiro Kodama Mayumi Egusa Chikara Masuta Hiroyuki Sawada Daisuke Shibata Koichi Hori Yuichiro Watanabe 《Journal of General Plant Pathology》2005,71(1):8-22
Lycopersicon esculentum cultivar Micro-Tom is a miniature tomato with many advantages for studies of the molecular biology and physiology of plants. To evaluate the suitability of Micro-Tom as a host plant for the study of pathogenesis, Micro-Tom plants were inoculated with 16 well-known fungal, bacterial, and viral pathogens of tomato. Athelia rolfsii, Botryotinia fuckeliana, Oidium sp., Phytophthora infestans, and Sclerotinia sclerotiorum caused typical symptoms and sporulated abundantly on Micro-Tom. Micro-Tom was resistant to Alternaria alternata, Corynespora cassiicola, and Fusarium oxysporum. When Micro-Tom was inoculated with 17 isolates of Ralstonia solanacearum, many isolates induced wilt symptoms. Agrobacterium tumefaciens also was pathogenic, causing crown galls on stem tissue after needle prick inoculation. In Micro-Tom sprayed with Pseudomonas syringae pv. tomato, P. s. pv. tabaci, or P. s. pv. glycinea, bacterial populations did not increase, and yellow lesions appeared only on leaves sprayed with P. s. pv. tomato. Tomato mosaic virus, Tomato aspermy virus, and Cucumber mosaic virus systemically infected Micro-Tom, which developed symptoms characteristic of other cultivars of tomato after infection with the respective virus. These results indicated that Micro-Tom was generally susceptible to most of the important tomato pathogens and developed typical symptoms, whereas certain pathogens were restricted by either hypersensitive resistance or nonhost resistance on Micro-Tom. Therefore, an assortment of Micro-Tom–pathogen systems should provide excellent models for studying the mechanism of susceptible and resistant interactions between plants and pathogens. 相似文献
117.
Journal of Plant Diseases and Protection - The effects of infections of Barley yellow dwarf virus (BYDV), Fusarium culmorum and F. graminearum alone as well as double infections of BYDV and... 相似文献
118.
Effects of sub-minimum inhibitory concentration antibiotic levels and temperature on growth kinetics and outer membrane protein expression in Mannheimia haemolytica and Haemophilus somnus 下载免费PDF全文
Brenda Y. Reeks Franklin R. Champlin Daniel B. Paulsen Daniel W. Scruggs Mark L. Lawrence 《Canadian journal of veterinary research》2005,69(1):1-10
The objective of this study was to determine the effects of sub-minimum inhibitory concentrations (sub-MICs) of 2 veterinary antibiotic preparations, chlortetracycline (CTC) and chlortetracycline-sulfamethazine (CTC + SMZ), on growth kinetics and outer membrane protein expression in Mannheimia haemolytica and Haemophilus somnus at normal and febrile body temperatures. Sub-minimum inhibitory concentrations of both antibiotics reduced the growth rates of M. haemolytica and H. somnus. Growth of both species was not inhibited when grown at 41 degrees C compared to 37 degrees C. There was no detectable consistent effect of antibiotic or temperature on outer membrane protein expression for either species. Our study indicates that sub-MIC levels of CTC and CTC + SMZ markedly impair growth of clinical M. haemolytica and H. somnus isolates, potentially allowing more effective host clearance during infection. 相似文献
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