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Claire Campion Catherine Chatot Bernard Perraton Didier Andrivon 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(9):983-992
A collection of 241 isolates of Rhizoctonia solani obtained from potato plants grown in different areas in France was characterized for anastomosis grouping, symptomatology on tubers of different cultivars and sensitivity to three fungicides. Most isolates collected belonged to (anastomosis groups (AGs)) AG 3, but 2% and 4% of the isolates were AG 5 and AG 2-1. AG 3 and AG 2-1 isolates were mostly obtained from sclerotia on tubers, but all AG 5, some AG 3 and some AG 2-1 isolates were recovered from superficial tuber alterations, like deformations, corky or scabby lesions. Sclerotia were formed on tubers produced by healthy stem cuttings grown in soil artificially infested with AG 3, but not on tubers grown in soil infested with either AG 5 or AG 2-1. No variation in susceptibility to sclerotial formation was observed among five potato cultivars. In all cases, a large proportion of tubers showed superficial corky lesions, often associated with deformations. The proportion of tubers with lesions and deformations was highest in soil infested with AG 2-1 and significantly lower on cv. Samba in all treatments. All isolates were highly sensitive to flutolanil, iprodione and pencycuron, except the AG 5 isolates, moderately sensitive to pencycuron. These results show that, although AG 3 is the most common R. solani group on potato in France, AG 5 and AG 2-1 may be present. Isolates differed for pathogenicity. In vitro sensitivity to fungicides varied among AGs. 相似文献
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Claire N. Lieske James H. Clark Howard G. Meyer Leigh Boldt Martin D. Green John R. Lowe Walter E. Sultan Peter Blumbergs Matthew A. Priest 《Pesticide biochemistry and physiology》1984,22(3):285-294
The inhibition of eel acetylcholinesterase by the 4-nitrophenyl esters of 2-furyl(methyl)-, methyl(2-thienyl)-, di-2-furyl-, and di-2-thienylphosphinic acid (I, II, III, and IV, respectively) was investigated at pH 6.90 in 0.067 M phosphate buffer (25.0°C) using stopped-flow instrumentation and automated data processing. Our evaluation of the dissociation constant, Kd, the unimolecular bonding rate constant, k2, and the bimolecular reaction constant, ki, are the first reported values for these constants for alkyl/heteroaryl and diheteroaryl esters of phosphinic acids. The largest ki value (19,330 M?1 sec?1) was observed for the reaction of I with the enzyme. The order for the remaining three is II > IV > III. There is no direct relationship between the hydrolysis rates of the esters and their anticholinesterase activities on eel acetylcholinesterase. Likewise, there is no direct relationship between their anticholinesterase activities and the LD50 values in rats. 相似文献
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Captive leopard geckos (Eublepharis macularius) often present to the exotic clinic for gastrointestinal impactions, follicular stasis, or dystocia. To our knowledge, normal ultrasonographic anatomy of these lizards has not been described. The objectives of this prospective, anatomic, analytical study were to develop ultrasound techniques for this species and to describe the normal sonographic anatomy of the head, coelomic cavity, and tail. Eleven, healthy, female leopard geckos were included. A linear array 13–18 MHz transducer was used. Geckos were sedated and restrained in dorsal recumbency for coelomic structure examination and in ventral recumbency for head and tail examinations. Sagittal and transverse images were acquired and authors recorded qualitative and quantitative ultrasonographic characteristics of anatomic structures. The ventral surface of the lungs, liver, gallbladder, caudal vena cava, portal vein, ventral abdominal vein, aorta, ovarian follicles, fat bodies, tail, and brain were visualized in 10 of 11 individuals. In one individual, molt precluded ultrasonographic examination. The heart, kidneys, urinary bladder, spleen, and pancreas were not visualized. The digestive tract was observed in 10 individuals but was too small to be measured. Findings from the current study could be used as a reference for future studies of leopard geckos. 相似文献
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Bowman DD Torre CJ Mannella C 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(4):293-304
Heartworm infection in dogs and cats in the western United States is a fairly new phenomenon, and for this reason it is often considered to be of minimal significance.The purpose of this survey was to collect data from 11 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming) in an effort to assess awareness of heartworm disease and identify areas in which improvement in understanding is needed. To accomplish this goal, veterinary clinics and hospitals in these states were sent a one-page survey in early 2006. The results of the survey demonstrate that cases of heartworm disease have been reported in all 11 states, illustrating the importance of annual testing and the routine use of preventives. 相似文献
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Albertine Léon Stéphane Pronost Jackie Tapprest Nathalie Foucher Béatrice Blanchard Geneviève André-Fontaine Claire Laugier Guillaume Fortier Roland Leclercq 《Journal of veterinary diagnostic investigation》2006,18(2):218-221
Studies were carried out to determine the cause of death in a prematurely born Thoroughbred foal that died 24 hours after birth. Necropsy revealed gross lesions suggestive of septicemia. A commercial Leptospira polymerase chain reaction (PCR) assay designed to specifically amplify the hemolysis-associated protein 1 (hap1) gene present only in pathogenic Leptospira strains detected the presence of Leptospira DNA in various tissues of the foal. Histologic examination of lung, liver, kidney, and myocardium revealed numerous spirochetes in Warthin-Starry-stained tissue sections. Results of PCR analysis and histologic examination suggested a leptospiral infection in the newborn foal. At the moment of death, the infection coexisted with a streptococcal-associated aspiration bronchopneumonia and postpartum septicemia. These findings indicate that the PCR assay based on the amplification of the hap1 gene represents a useful tool for specific detection of pathogenic leptospira in field samples taken from horses. 相似文献