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521.
Powell T. Slinkard Elissa K. Randall Lynn R. Griffin 《Canadian journal of veterinary research》2021,85(2):131
The purpose of this retrospective analysis was to determine if fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) could potentially be an accurate staging tool for detecting metastatic lymph nodes in dogs with appendicular osteosarcoma based on the quantitative measurement of the maximum standard uptake value (SUVmax) of lymph nodes. A total of 53 dogs were identified that presented for staging via 18F-FDG PET/CT for primary appendicular osteosarcoma. Patients were categorized according to lymph node status of having either metastatic or non-metastatic nodes based on cytological or histological analysis. Maximum standard uptake (SUVmax) values of the sampled lymph node(s) were recorded and 3/77 (3.9%) of sampled lymph nodes were confirmed metastatic. A Mann-Whitney test revealed a statistical difference in the SUVmax of the metastatic versus non-metastatic lymph nodes [median: 6.6 to 95% confidence interval (CI): 2.56 to 14.37 versus 2.18 95% CI: 2.32 to 3.17, respectively, P-value = 0.05]. This retrospective analysis revealed a significant difference in the SUVmax as measured on 18F-FDG PET/CT between metastatic lymph nodes and non-metastatic lymph nodes in canine patients afflicted with appendicular osteosarcoma, in spite of the small numbers analyzed. While these results are promising, they should be interpreted with caution and further studies are justified. 相似文献
522.
Parris N Dickey LC Powell MJ Coffin DR Moreau RA Craig JC 《Journal of agricultural and food chemistry》2002,50(11):3306-3308
Dry-milled yellow corn and freshly ground food and nonfood grade yellow and white hybrid corn kernels were pretreated in a solution of lactic acid and sodium metabisulfite followed by extraction with 70% ethanol. Zein was precipitated from the extract by reducing the ethanol content of the extract to 40%. Lipid associated with the zein isolates was between 15 and 20% and contained mostly endogenous free fatty acids. The effect of the endogenous free fatty acids on zein isolate films, with and without free fatty acids, was determined by measuring various film properties. Stress-strain measurements indicated 40-200% greater elongation for zein films containing endogenous free fatty acids. Films prepared from zein isolated from preground corn stored for approximately 4 months (27 degrees C, 17% relative humidity) had approximately 3 times greater elongation values than zein films prepared from freshly ground corn. 相似文献
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524.
Powell TM Richerson PJ Dillon TM Agee BA Dozier BJ Godden DA Myrup LO 《Science (New York, N.Y.)》1975,189(4208):1088-1090
Spectral analysis of current speed and chlorophyll a measurements in Lake Tahoe, California and Nevada, indicates that considerably more variance exists at longer length scales in chlorophyll than in the current speeds. Increasingly, above scales of approximately 100 meters, chlorophyll does not behave as a simple passive contaminant distributed by turbulence, which indicates that biological processes contribute significantly to the observed variance at these large length scales. 相似文献
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526.
Tabuchi K Blundell J Etherton MR Hammer RE Liu X Powell CM Südhof TC 《Science (New York, N.Y.)》2007,318(5847):71-76
Autism spectrum disorders (ASDs) are characterized by impairments in social behaviors that are sometimes coupled to specialized cognitive abilities. A small percentage of ASD patients carry mutations in genes encoding neuroligins, which are postsynaptic cell-adhesion molecules. We introduced one of these mutations into mice: the Arg451-->Cys451 (R451C) substitution in neuroligin-3. R451C mutant mice showed impaired social interactions but enhanced spatial learning abilities. Unexpectedly, these behavioral changes were accompanied by an increase in inhibitory synaptic transmission with no apparent effect on excitatory synapses. Deletion of neuroligin-3, in contrast, did not cause such changes, indicating that the R451C substitution represents a gain-of-function mutation. These data suggest that increased inhibitory synaptic transmission may contribute to human ASDs and that the R451C knockin mice may be a useful model for studying autism-related behaviors. 相似文献
527.
Thioformaldehyde (H(2)CS) has been detected and characterized from its microwave spectrum. Preliminary analysis of rotational transitions for the sulfur-32-containing form of H(2)CS shows this new species to have C(2v) symmetry with rotational constants (in megahertz) of A = 292,729, B = 17,698, and C = 16,652. The possibility of detection of thioformaldehyde in the interstellar medium is discussed, and a table of transitions expected to be of importance for that detection is presented. 相似文献
528.
MacPhee AG Tate MW Powell CF Yue Y Renzi MJ Ercan A Narayanan S Fontes E Walther J Schaller J Gruner SM Wang J 《Science (New York, N.Y.)》2002,295(5558):1261-1263
Synchrotron x-radiography and a fast x-ray detector were used to record the time evolution of the transient fuel sprays from a high-pressure injector. A succession of 5.1-microsecond radiographs captured the propagation of the spray-induced shock waves in a gaseous medium and revealed the complex nature of the spray hydrodynamics. The monochromatic x-radiographs also allow quantitative analysis of the shock waves that has been difficult if not impossible with optical imaging. Under injection conditions similar to those found in operating engines, the fuel jets can exceed supersonic speeds and result in gaseous shock waves. 相似文献
529.
Powell JW 《Science (New York, N.Y.)》1887,9(229):612-614
530.