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11.
Stuart A. MacFarlane Derek J. F. Brown John F. Bol 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(5):535-539
The coat protein gene of the nematode non-transmissible, SP5 isolate of pea early-browning tobravius was replaced with that of the highly nematode transmissible, PPK20 isolate of tobacco rattle tobravirus. Plants were infected with the recombinant virus when mechanically inoculated and the virus invaded the plants systemically. However, although the PPK20 isolate of TRV was transmitted by nematodes from these plants, the recombinant virus was not transmitted. Therefore, the virus coat protein is not the exclusive determinant of nematode transmission. 相似文献
12.
Quantitative PCR and visual monitoring of Mycosphaerella graminicola epidemics were performed to investigate the effect of curative and preventative applications of azoxystrobin in wheat field crops. A non-systemic protectant and a systemic curative fungicide, chlorothalonil and epoxiconazole, respectively, were used as references. PCR diagnosis detected leaf infection by M graminicola 3 weeks before symptom appearance, thereby allowing a clear distinction between curative and preventative treatments. When applied 1 week after the beginning of infection, azoxystrobin curative activity was intermediate between chlorothalonil (low effect) and epoxiconazole. When applied preventatively, none of the fungicides completely prevented leaf infection. There was some indication that azoxystrobin preventative treatments may delay fungal DNA increase more than epoxiconazole at the beginning of leaf infection. Both curative and preventative treatments increased the time lapse between the earliest PCR detection and the measurement of a 10% necrotic leaf area. Azoxystrobin only slightly decreased the speed of necrotic area increase compared with epoxiconazole. Hence, azoxystrobin activity toward M graminicola mainly resides in lengthening the time lapse between the earliest PCR detection and the measurement of a 10% necrotic leaf area. Information generated in this way is useful for optimal positioning of azoxystrobin treatments on M graminicola. 相似文献
13.
Marie Ren Gramer Jee Hoon Lee Young Ki Choi Sagar M. Goyal Han Soo Joo 《Canadian journal of veterinary research》2007,71(3):201-206
The H3N2 subtype of influenza A viruses isolated from pigs in the United States and Canada has shown both genetic and antigenic diversity. The objective of this study was to determine the serologic and genetic characteristics of contemporary strains of these viruses. Genetic analysis of 18 reference strains and 8 selected strains demonstrated differences in 1% to 9% of the nucleotides of the hemagglutinin (HA) gene. Phylogenetic analysis of the HA gene revealed 3 genetic clusters, as well as divergence of cluster III viruses from a cluster III prototype virus (A/Swine/Illinois/21587/99). By means of 1-way cross-hemagglutination inhibition with antiserum against 5 field isolates and 3 vaccine viruses, most of 97 isolates tested could be placed in 1 of 3 serogroups. The several isolates that did not react with any antiserum were in genetic cluster III, which suggests that continuous antigenic drift in cluster III may have resulted in virus variants. The efficacy of commercial vaccines against these virus variants should be evaluated with vaccination and challenge studies. 相似文献
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当今世界的农业发展概况 当今世界的农业,广袤、多样且快速变化.如果地方层面、国家层面乃至全球层面都有健全的政策和支持性投入,今天的农业将为数以亿计的农村穷人摆脱贫困提供新的契机.农业向他们敞开脱贫道路包括家庭种植业和养殖业、高附加值的"新型农业"就业机会、新兴的农村非农产业创业和就业机会等等. 相似文献
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Sophie St-Hilaire Derek Price Shawna Taylor David Groman 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(8):876-878
Rainbow trout (average weight of 2 g) in fresh water experienced high mortality and were infected with a diplomonad intestinal parasite. Tanks of fish experienced an immediate reduction in mortality after an in-feed treatment with 3% Epsom salts for 2 d. Treatments had to be applied several times, but in each case there was a similar reduction in mortality. 相似文献
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Geun Hye Hwang Yu Jin Jeon Ho Jae Han Soo Hyun Park Kyoung Min Baek Woochul Chang Joong Sun Kim Lark Kyun Kim You-Mie Lee Sangkyu Lee Jong-Sup Bae Jun-Goo Jee Min Young Lee 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(1):17-23
Butylated hydroxyanisole (BHA) is a synthetic phenolic compound consisting of a mixture of two isomeric organic compounds: 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. We examined the effect of BHA against hydrogen peroxide (H2O2)-induced apoptosis in primary cultured mouse hepatocytes. Cell viability was significantly decreased by H2O2 in a dose-dependent manner. Additionally, H2O2 treatment increased Bax, decreased Bcl-2, and promoted PARP-1 cleavage in a dose-dependent manner. Pretreatment with BHA before exposure to H2O2 significantly attenuated the H2O2-induced decrease of cell viability. H2O2 exposure resulted in an increase of intracellular reactive oxygen species (ROS) generation that was significantly inhibited by pretreatment with BHA or N-acetyl-cysteine (NAC, an ROS scavenger). H2O2-induced decrease of cell viability was also attenuated by pretreatment with BHA and NAC. Furthermore, H2O2-induced increase of Bax, decrease of Bcl-2, and PARP-1 cleavage was also inhibited by BHA. Taken together, results of this investigation demonstrated that BHA protects primary cultured mouse hepatocytes against H2O2-induced apoptosis by inhibiting ROS generation. 相似文献
20.
Gutzeit D Klaubert B Rychlik M Winterhalter P Jerz G 《Journal of agricultural and food chemistry》2007,55(10):3978-3984
A stable isotope dilution assay for quantification of pantothenic acid in sea buckthorn berries, juice, and concentrate using a four-fold labeled isotopologue of vitamin B5 as the internal standard was adopted using reversed phase liquid chromatography-mass spectrometry with electrospray ionization. Because of a rapid sample clean up procedure without the necessity of external calibration, this methodology permits the accurate analysis of a high number of samples within a short time. Sea buckthorn juice was stored at 25 and 40 degrees C for up to 7 days to determine the effects of storage temperature on the stability of pantothenic acid. Analysis of kinetic data suggested that the degradation follows a first-order model. The results of the experiments showed that storage of sea buckthorn juice for 7 days at ambient temperature (25 degrees C) already resulted in a significant degradation of pantothenic acid of about 18%. The processing effects of juice production and subsequent concentration revealed a decrease of about 6-7% in the juice and of 23% in the juice concentrate. 相似文献