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911.
A fluorescence assay for phenylalanine transfer RNA 总被引:3,自引:0,他引:3
912.
The isoenzymes of human parotid amylase 总被引:4,自引:0,他引:4
D L Kauffman N I Zager E Cohen P J Keller 《Archives of biochemistry and biophysics》1970,137(2):325-339
913.
914.
Studies on the mechanism of the enzymatic reactivation of antibody-neutralized poliovirus 总被引:6,自引:0,他引:6
R Keller 《Journal of immunology (Baltimore, Md. : 1950)》1968,100(5):1071-1099
915.
916.
Yorke G. Jacobson Melvin Keller Eldred D. Mundth Alfred J. Defalco James E. Mc Clenethan 《The Western journal of medicine》1966,105(2):93-96
Oxygen therapy at atmospheric and increased pressure was used in the treatment of experimental hemorrhagic shock. Arterial gases, pH, lactate and pyruvate were determined and compared. Survival was carefully followed and complete pathological evaluation was carried out. The results showed no difference between control animals and those in the hyperbaric oxygen therapy group. It was concluded that hyperbaric oxygen therapy post facto did not influence the metabolic or survival data in this experiment. 相似文献
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918.
919.
Refinement of a morphological scoring system for postimplantation rabbit conceptuses 总被引:1,自引:0,他引:1
Carney EW Tornesi B Keller C Findlay HA Nowland WS Marshall VA Ozolins TR 《Birth defects research. Part B, Developmental and reproductive toxicology》2007,80(3):213-222
BACKGROUND: The rabbit is used extensively in developmental toxicity testing, yet basic information on rabbit embryo development is lacking. The goals of this study were to refine a rabbit embryo morphology scoring system, and use it to evaluate rabbit whole embryo cultures (WEC). METHODS: A total of 265 conceptuses were harvested between GD 8.0 and 12.0 (coitus = GD 0) at 6-hr intervals and examined in detail. Discreet developmental landmarks were then established for 18 morphological features and assigned scores ranging from 0 up to 6. The scoring system was then validated on a subset of randomly selected in vivo conceptuses, and was used to evaluate conceptuses grown for 12, 24, 36, or 48 hr in WEC beginning from GD 9.0 or 10.0. A few embryos also were examined using microscopic computed tomography (microCT)-based virtual histologytrade mark to assess the utility of this technology. RESULTS: Morphology scores of in vivo developed conceptuses increased linearly (r2 = 0.98) with advancing gestational age, from means of 0.0 on GD 8.0 to 67.9 on GD 12.0. Application of the scoring system, supplemented with evidence from Virtual histologytrade mark, indicated that the WEC system supported normal morphological development of rabbit conceptuses. However, when explanted at GD 9, the rate of development was about 20% slower than in vivo, whereas the rate of development in WEC from GD 10 was indistinguishable from in vivo. CONCLUSIONS: This work enhances the evaluation tools available to study mechanisms of normal and abnormal development in this widely used animal testing species. 相似文献
920.
We present an experimental investigation of microtubule dynamic instability in three dimensions, based on laser light-sheet fluorescence microscopy. We introduce three-dimensional (3D) preparation of Xenopus laevis egg extracts in Teflon-based cylinders and provide algorithms for 3D image processing. Our approach gives experimental access to the intrinsic dynamic properties of microtubules and to microtubule population statistics in single asters. We obtain evidence for a stochastic nature of microtubule pausing. 相似文献