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221.
S. MORAN 《EPPO Bulletin》1991,21(1):73-80
Whole wheat grains impregnated with 0.02, 0.05 and 0.2% sodium fluoroacetate, and 2% zinc phosphide, were offered to series of single caged individuals of Microtus guentheri and Meriones tristrami. In most cases the sodium fluoroacetate treated baits were well accepted by both species. The acceptance of the zinc phosphide-treated bait was partial in all the series tested. The approximate LD50 ranges of sodium fluoroacetate are between 0.24 and 0.43 mg kg−1 for M. guentheri , and, perhaps, for the jirds too, and for zinc phosphide—between 32.6 and 58.8 mg kg−1 for M. tristrami , and a similar value, more or less, for M. guentheri. 相似文献
222.
Intestinal parasites: a study of human appendices 总被引:2,自引:0,他引:2
Histological sections of 414 appendices were examined parasitologically. Enterobius vermicularis was found in 8.7%, eggs of Ascaris lumbricoides in 0.5%, trophozites of Dientamoeba fragilis in 4.8%, Endolimax nana in 2.2%, Entamoeba coli in 1% and cysts of Giardia intestinalis in 1.9% of cases. Appendicopathies associated with Enterobius were most frequent in the age group from 6 to 10 years (24.3%) and from 21 to 25 years (12.2%). Patients older than 15 years were practically women only. Dientamoeba was most frequent in the age group from 11 to 15 years (11.3%). In women D. fragilis was three times more frequent than in men. The coincidence of D. fragilis and E. vermicularis infections was 50%. No interactions were seen between the protozoans in the contents of the appendix and its mucous membrane. Statistical evaluation indicates possible etiologic role of E. vermicularis in the occurrence of acute appendicities. D. fragilis appears to be the most common intestinal protozoan parasite in Bohemia. 相似文献
223.
224.
S. Savary 《European journal of plant pathology / European Foundation for Plant Pathology》1987,93(4):167-188
Groundnut diseases were surveyed in the various traditional cropping regions of Ivory Coast during 1982, 1983 and 1984. The methods used during the survey are described. A preliminary analysis of the results aimed at a characterization of a complex, multiple pathosystem is presented. The analysis especially focuses upon some foliar diseases, and particularly on rust, caused byPuccinia arachidis. The results show the great variability of the climates and of the agricultural techniques which are associated to groundnut cropping. The list of the fungal pathogens which affect groundnut is long: 16 have been identified during the survey, of which 6 are omnipresent in the various regions. A correspondence analysis was performed, allowing to describe the average development of the multiple pathosystem: groundnut-rust-leafsport-wilting fungi. Endemicity in tropical pathosystems is also analyzed in the case of the main foliar diseases (rust and Cercospora leafspots). More specifically, the epidemiology of groundnut rust in southern Ivory Coast is interpreted as regular, explosive epidemics developping on an endemic background. Every year epidemics develop in the northern and central areas too, most of their primary inoculum supposedly originating from the infested southern crops. Probably, intensification of agriculture will strongly favour rust disease. 相似文献
225.
Xanthomonas ampelina can be detected with the same sensitivity by ELISA double-antibody sandwich (ELISA-DAS) or indirect ELISA (ELISA-I) but the latter is preferred for its greater simplicity. The two methods also gave similar sensitivity results for soft-rot erwinias, but their application is complicated by the large number of erwinia serotypes. ELISA-I was unable to distinguish strains of Agrobacterium tumefaciens from A. radiobacter. The cross reactions with other bacteria of antisera against X. fragariae were tested by ELISA-I. The problems of applying these methods are discussed. 相似文献
226.
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228.
Enserink M 《Science (New York, N.Y.)》2001,291(5505):812-817
229.
Ladika S 《Science (New York, N.Y.)》2001,293(5534):1422-1423
230.
Speidel MT 《Science (New York, N.Y.)》2001,293(5531):801