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51.
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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
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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
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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
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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.
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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Rajendran L Schneider A Schlechtingen G Weidlich S Ries J Braxmeier T Schwille P Schulz JB Schroeder C Simons M Jennings G Knölker HJ Simons K 《Science (New York, N.Y.)》2008,320(5875):520-523
beta-Secretase plays a critical role in beta-amyloid formation and thus provides a therapeutic target for Alzheimer's disease. Inhibitor design has usually focused on active-site binding, neglecting the subcellular localization of active enzyme. We have addressed this issue by synthesizing a membrane-anchored version of a beta-secretase transition-state inhibitor by linking it to a sterol moiety. Thus, we targeted the inhibitor to active beta-secretase found in endosomes and also reduced the dimensionality of the inhibitor, increasing its local membrane concentration. This inhibitor reduced enzyme activity much more efficiently than did the free inhibitor in cultured cells and in vivo. In addition to effectively targeting beta-secretase, this strategy could also be used in designing potent drugs against other membrane protein targets. 相似文献