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991.
In February 2004, a disease of strawberry (Fragaria × ananassa Duch.), causing little-leaf, proliferation, malformation of fruits, and marginal chlorosis of leaves, occurred in Ehime Prefecture,
Japan. The causal pathogen was identified as a phloem-restricted bacterium-like organism, “Candidatus Phlomobacter fragariae,” based on polymerase chain reaction (PCR) detection, electron microscopy, and sequence analysis of
PCR products. This is the first report of strawberry marginal chlorosis in Asia.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number AB246669. 相似文献
992.
Dionisio G. Alvindia Takao Kobayashi Keiko T. Natsuaki 《Journal of General Plant Pathology》2006,72(4):257-260
The fungal population in the air and on developing fruit on a nonchemical banana farm in the Philippines was estimated from
January 1998 to December 2001 to follow the source, determine the origin, and establish the population dynamics of various
fungi associated with postharvest diseases of banana. Forty fungal genera were found in the air on a nonchemical banana farm
and 26 were found on developing fruit. Spore density in the air and on the surface of developing fruit varied with seasonal
patterns. Fungi of various species were detected on the farm and on developing banana fruit, but it has not been established
as to when a specific fungus arrived at the farm and on the fruit. The results suggest that the source and origin of fungi
associated with postharvest diseases of banana fruit in Japan imported from the Philippines were the farm itself, and the
fungal association with banana fruit began at flower emergence. 相似文献
993.
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996.
Furukawa S Nagashima Y Hoshi K Hirao H Tanaka R Maruo K Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(1):41-44
In veterinary medicine, dopamine is currently being administered clinically by infusion for treatment of kidney disorders at low doses (< or = 3 microg/kg/min) and for assessment of hemodynamics at high doses (> or = 5 microg/kg/min). However, since high doses of dopamine cause peripheral vasoconstriction due to its effect on alpha adrenoceptors, high doses have no longer been recommended. The present study was conducted to explore possible regimens for the use of dopamine infusion in dogs. The regional (renal and cardiac) blood flow for 60 min was measured by using colored microspheres at three doses (3, 10 and 20 microg/kg/min) of dopamine infusion in healthy anesthetized mongrel dogs. The effects on kidney and peripheral hemodynamics at each dose and the resultant cardiac output, mean arterial blood pressure and total peripheral resistance were determined. Renal blood flow increased markedly at 3 microg/kg/min dopamine. Improvement in hemodynamics indicated by marked increase in cardiac blood flow, cardiac output and mean arterial blood pressure and decreased total peripheral resistance was observed at higher doses (10 and 20 microg/kg/min). At 10 microg/kg/min, in addition to the satisfactory increase in cardiac blood flow, there was also a stable satisfactory increase in renal blood flow. However, at 20 microg/kg/min, increased myocardial oxygen consumption (manifested by marked increased in cardiac output), arrythmia and irregular increase in renal blood flow were detected. This study suggests that the clinical use of dopamine infusion in dogs could be safely expanded to moderately higher doses. 相似文献
997.
Endo H Kimura J Sasaki M Matsuzaki M Matsubayashi H Tanaka K Fukuta K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(10):901-905
The mastication muscles were examined in the lesser (Tragulus javanicus) and greater mouse deer (Tragulus napu) to clarify the form of the mastication muscles in these primitive artiodactyls. The M. masseter was well-developed in both species, however the attachment area of its origin was not confirmed in the rostral facial part. The masseter bundles were not observed on the lateral side of the maxilla bone, and their origin was restricted to the zygomatic arch area. This suggests that the M. masseter may not act as a motor raising the mandible rostro-dorsally, but pull the insertion vertically unlike the highly derived grazer of Bovidae. The Crista temporalis was weak and the M. temporalis was thin in the mouse deer, and this indicates that the M. temporalis may not be important in the mastication in the primitive artiodactyls. These findings suggest that the browser such as mouse deer has been adapted for the feeding on soft leaves, and functional-morphologically different in mastication strategy from the grazer such as developed Bovidae species. The architecture of the mastication muscles was not different between the two species. However, in the muscle weight ratios per body weight, the M. temporalis and the M. digastricus were significantly smaller in greater mouse deer than in lesser mouse deer. 相似文献
998.
Wauchope RD Yeh S Linders JB Kloskowski R Tanaka K Rubin B Katayama A Kördel W Gerstl Z Lane M Unsworth JB 《Pest management science》2002,58(5):419-445
The soil sorption coefficient Kd and the soil organic carbon sorption coefficient KOC of pesticides are basic parameters used by environmental scientists and regulatory agencies worldwide in describing the environmental fate and behavior of pesticides. They are a measure of the strength of sorption of pesticides to soils and other geosorbent surfaces at the water/solid interface, and are thus directly related to both environmental mobility and persistence. KOC is regarded as a 'universal' parameter related to the hydrophobicity of the pesticide molecule, which applies to a given pesticide in all soils. This assumption is known to be inexact, but it is used in this way in modeling and estimating risk for pesticide leaching and runoff. In this report we examine the theory, uses, measurement or estimation, limitations and reliability of these parameters and provide some 'rules of thumb' for the use of these parameters in describing the behavior and fate of pesticides in the environment, especially in analysis by modeling. 相似文献
999.
1000.
Photochemical demethylation of monuron [3-(4-chlorophenyl)-1, 1-dimethylurea] and of demethylmonuron [ 1-(4-chlorophenyl)-3-methylurea] in aqueous solution was investigated. The photoproducts identified in this study were formaldehyde, formic acid and carbon dioxide. These products indicate that demethylation occurs either by oxidation of a methyl group to hydroxymethyl which is readily cleaved to yield formaldehyde, or by further oxidation to an N-formyl group, which is slowly hydrolysed under weakly acidic conditions to yield formic acid. Samples equilibrated either with air or oxygen (> 99 % purity) gave essentially the same yield of oxidation products. Experimental evidence indicated that extensive photodegradation of formaldehyde was occurring during photolysis, causing low recoveries of formaldehyde. Consequently, with [2H3-methyl]demethylmonuron and deuterated water, only steady state concentrations of formaldehyde could be measured in an isotopic study. 相似文献