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51.
鹿蹄草等中草药对油桃采后褐腐病抑制效果研究 总被引:5,自引:2,他引:5
在离体和活体条件下,测定鹿蹄草、厚朴等中草药单剂及鹿蹄草为主的各中草药复配组合对油桃采后褐腐病菌的抑制效果。结果表明:11号(鹿蹄草+厚朴+大黄),14号(鹿蹄草+高良姜+虎杖)复配组合在离体试验中抑菌效果最好,10 mg/mL浓度的抑制率分别达到89.77%,85.50%;两种组合的最小抑菌浓度(MIC)分别是1.25,2.5 mg/mL;最小杀菌浓度(MBC)分别是2.5,5.0 mg/mL。活体抑菌测定结果表明,11号和14号复配组合对油桃褐腐病菌有不同程度延缓侵染和抑制作用,但不能完全防治;0.05 mg/mL扑海因与11号组合20 mg/mL,0.10 mg/mL扑海因与11号组合10 mg/mL均能完全抑制褐腐病菌在油桃果实上的发生和蔓延。 相似文献
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M A Simons 《The Veterinary record》1975,97(21):408-410
The current position of the horse in the United Kingdom is discussed and the attitudes of the horse-owning public are examined. It is suggested that there are welfare, economic and practical advantages to owners and the veterinary profession in a veterinary health scheme for horses. A scheme which has been tried successfully in the field is discussed. 相似文献
54.
The widely varying values given for the membrane thickness in hen's eggs suggest that a critical comparison of the methods of measurement is necessary. The membrane thickness was measured in pieces of isolated membranes, in decalcified sections and in ground sections. The first method gave the lowest values, probably owing to the impossibility of separating the whole of the membranes from the calcified shell. The other two methods showed an average difference in results of only 7.2–10.5 per cent. It was concluded that the actual thickness of dry egg shell membranes can only be measured in sections and that, without correction, such values should not be compared with those taken in isolated membranes. 相似文献
55.
The 2011 magnitude 9.0 Tohoku-Oki earthquake: mosaicking the megathrust from seconds to centuries 总被引:5,自引:0,他引:5
Simons M Minson SE Sladen A Ortega F Jiang J Owen SE Meng L Ampuero JP Wei S Chu R Helmberger DV Kanamori H Hetland E Moore AW Webb FH 《Science (New York, N.Y.)》2011,332(6036):1421-1425
Geophysical observations from the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki, Japan earthquake allow exploration of a rare large event along a subduction megathrust. Models for this event indicate that the distribution of coseismic fault slip exceeded 50 meters in places. Sources of high-frequency seismic waves delineate the edges of the deepest portions of coseismic slip and do not simply correlate with the locations of peak slip. Relative to the M(w) 8.8 2010 Maule, Chile earthquake, the Tohoku-Oki earthquake was deficient in high-frequency seismic radiation--a difference that we attribute to its relatively shallow depth. Estimates of total fault slip and surface secular strain accumulation on millennial time scales suggest the need to consider the potential for a future large earthquake just south of this event. 相似文献
56.
Cox-Foster DL Conlan S Holmes EC Palacios G Evans JD Moran NA Quan PL Briese T Hornig M Geiser DM Martinson V vanEngelsdorp D Kalkstein AL Drysdale A Hui J Zhai J Cui L Hutchison SK Simons JF Egholm M Pettis JS Lipkin WI 《Science (New York, N.Y.)》2007,318(5848):283-287
In colony collapse disorder (CCD), honey bee colonies inexplicably lose their workers. CCD has resulted in a loss of 50 to 90% of colonies in beekeeping operations across the United States. The observation that irradiated combs from affected colonies can be repopulated with naive bees suggests that infection may contribute to CCD. We used an unbiased metagenomic approach to survey microflora in CCD hives, normal hives, and imported royal jelly. Candidate pathogens were screened for significance of association with CCD by the examination of samples collected from several sites over a period of 3 years. One organism, Israeli acute paralysis virus of bees, was strongly correlated with CCD. 相似文献
57.
G Scamarcio F Capasso C Sirtori J Faist AL Hutchinson DL Sivco AY Cho 《Science (New York, N.Y.)》1997,276(5313):773-776
A quantum-cascade long-wavelength infrared laser based on superlattice active regions has been demonstrated. In this source, electrons injected by tunneling emit photons corresponding to the energy gap (minigap) between two superlattice conduction bands (minibands). A distinctive design feature is the high oscillator strength of the optical transition. Pulsed operation at a wavelength of about 8 micrometers with peak powers ranging from approximately 0.80 watt at 80 kelvin to 0.2 watt at 200 kelvin has been demonstrated in a superlattice with 1-nanometer-thick AlInAs barriers and 4.3-nanometer-thick GaInAs quantum wells grown by molecular beam epitaxy. These results demonstrate the potential of strongly coupled superlattices as infrared laser materials for high-power sources in which the wavelength can be tailored by design. 相似文献
58.
The trans Golgi network: sorting at the exit site of the Golgi complex 总被引:212,自引:0,他引:212
The Golgi complex is a series of membrane compartments through which proteins destined for the plasma membrane, secretory vesicles, and lysosomes move sequentially. A model is proposed whereby these three different classes of proteins are sorted into different vesicles in the last Golgi compartment, the trans Golgi network. This compartment corresponds to a tubular reticulum on the trans side of the Golgi stack, previously called Golgi endoplasmic reticulum lysosomes (GERL). 相似文献
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