John Martin Fischer

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The permeability of different brain tumor models to horseradish peroxidase (HRP) was examined by determining the fraction of tumor that contained HRP after intravenous administration. The intracerebral tumor models studied were Avian Sarcoma Virus (ASV)-induced tumors and tumors from transplanted RG-2, S69-C1-5, and 9L cell lines. The average fraction of(More)
Regional measurements of blood flow (F) were performed in transplanted intracerebral RG-2 rat gliomas using [14C]iodoantipyrine, Kety-Schmidt blood flow equations, and quantitative autoradiography. Twenty-nine intracranial tumors in ten rats were analyzed by location; 18 intraparenchymal, seven meningeal, two third-ventricular, and two fourth-ventricular(More)
Regional measurements of blood-to-tissue transport were performed in transplanted RG-2 rat gliomas using [alpha- 14C]aminoisobutyric acid (AIB), quantitative autoradiography, and equations to express a unidirectional transfer constant. Thirty-eight intracranial tumors in ten rats were analyzed according to location; 23 intraparenchymal tumors, eight(More)
The newborn beagle puppy serves as an animal model for intraventricular hemorrhage (IVH) of the premature infant. Since increased systemic blood pressure has been implicated in the genesis of IVH in both babies and puppies, we studied regional cerebral blood flow in control and hypertensive puppies. Hypertension significantly increased blood flow to all(More)
Autochthonous gliomas were induced in rats by intracerebral inoculation of avian of avian sarcoma virus and studied by 3H-thymidine autoradiography. Parenchymal glial tumor cells had a 3H-labeling index (LI) of 3.0 to 13.6%. Endothelial cells in tumor blood vessels had an LI of 2.6 to 34.3%, independent of and in most instances higher than the LI of the(More)
Physicalism is the thesis that everything is physical, including the mind. One argument against physicalism appeals to near-death experiences (NDEs), conscious experiences during episodes, such as cardiac arrest, when one's normal brain functions are severely impaired. The core contention is that NDEs cannot be physically explained, and so we have reason to(More)
This paper evaluates recent proposals for compatibilism about doxastic freedom, and attempts to refine them by applying Fischer and Ravizza's moderate reasons-responsiveness compatibilism to doxastic freedom. I argue, however, that even this refined version of doxastic compatibilism is subject to challenging counterexamples and is more difficult to support(More)
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