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871.
872.
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
873.
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875.
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
876.
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
877.
Howell WM Keller GE Kirkpatrick JD Jenkins RL Hunsinger RN McLaughlin EW 《Genetics and molecular research : GMR》2007,6(1):50-58
The purpose of the present study was to determine the effects of the steroidal plant hormone, 24-epibrassinolide (BL), on the mitotic index and growth of onion (Allium cepa) root tips. The classical Allium test was used to gather and quantify data on the rate of root growth, the stages of mitosis, and the number of mitoses in control and BL-treated groups of onions. Low doses of BL (0.005 ppm) nearly doubled the mean root length and the number of mitoses over that of controls. Intermediate doses of BL (0.05 ppm) also produced mean root lengths and number of mitoses that were significantly greater than those of the controls. The highest dose of BL (0.5 ppm) produced mean root lengths and number of mitoses that were less than control values, but the differences were not statistically significant. Examination of longitudinally sectioned root tips produced relatively similar results. This study confirms the suppositions of previous authors who have claimed that exogenously applied BL can increase the number of mitoses in plants, but failed to show cytogenetic data. This is the first report detailing the effects of BL on chromosomes and the cell cycle. 相似文献
878.
Gwinn K Corriveau RA Mitsumoto H Bednarz K Brown RH Cudkowicz M Gordon PH Hardy J Kasarskis EJ Kaufmann P Miller R Sorenson E Tandan R Traynor BJ Nash J Sherman A Mailman MD Ostell J Bruijn L Cwik V Rich SS Singleton A Refolo L Andrews J Zhang R Conwit R Keller MA;ALS Research Group 《PloS one》2007,2(12):e1254
Amyotrophic lateral sclerosis (ALS) is the most common form of motor neuron disease (MND). It is currently incurable and treatment is largely limited to supportive care. Family history is associated with an increased risk of ALS, and many Mendelian causes have been discovered. However, most forms of the disease are not obviously familial. Recent advances in human genetics have enabled genome-wide analyses of single nucleotide polymorphisms (SNPs) that make it possible to study complex genetic contributions to human disease. Genome-wide SNP analyses require a large sample size and thus depend upon collaborative efforts to collect and manage the biological samples and corresponding data. Public availability of biological samples (such as DNA), phenotypic and genotypic data further enhances research endeavors. Here we discuss a large collaboration among academic investigators, government, and non-government organizations which has created a public repository of human DNA, immortalized cell lines, and clinical data to further gene discovery in ALS. This resource currently maintains samples and associated phenotypic data from 2332 MND subjects and 4692 controls. This resource should facilitate genetic discoveries which we anticipate will ultimately provide a better understanding of the biological mechanisms of neurodegeneration in ALS. 相似文献
879.
Annemarie MM Vlaar Marinus JPG van Kroonenburgh Alfons GH Kessels Wim EJ Weber 《BMC neurology》2007,7(1):27
Background
Parkinson's disease (PD) is the second most common neurodegenerative disorder. One of the most widely used techniques to diagnose PD is a Single Photon Emission Computer Tomography (SPECT) scan to visualise the integrity of the dopaminergic pathways in the brain. Despite this there remains some discussion on the value of SPECT in the differential diagnosis of PD. We did a meta-analysis of all the existing literature on the diagnostic accuracy of both pre- and post-synaptic SPECT imaging in the differential diagnosis of PD. 相似文献880.