Dantrolene: evidence for effects on Na permeability properties of the nodal membrane

The effects of dantrolene on myelinated frog nerve fibers were studied in voltage clamp experiments. Dantrolene shifted the potential-dependent parameters describing Na+ permeability towards more negative membrane potentials. The findings are interpreted as a change in the negative surface charge of the membrane.     

Forces and causes in Kant’s early pre-Critical writings

This paper considers Kant’s conception of force and causality in his early pre-Critical writings, arguing that this conception is best understood by way of contrast with his immediate predecessors, such as Christian Wolff, Alexander Baumgarten, Georg Friedrich Meier, Martin Knutzen, and Christian August Crusius, and in terms of the scientific context of natural philosophy at the time. Accordingly, in the True estimation Kant conceives of force in terms of activity rather than in terms of specific effects, such as motion (as unnamed Wolffians had done). Kant’s explicit arguments in the Nova dilucidatio for physical influx (in the guise of the principle of succession) are directed primarily against the conception of grounds and existence held by Wolff, Baumgarten, and Meier, and only secondarily against Leibniz (by asserting the priority of bodies over mind rather than vice versa). Finally, Kant’s reconciliation of the infinite divisibility of space and the unity of monads in the Physical monadology is designed to respond to objections that could be raised naturally by Wolff and Baumgarten.     

17β-Hydroxymethyl-Steroide: Darstellung von Derivaten des 17β-Hydroxymethyl-4-androsten-3-ons

Summary Starting from methyl 3-oxo-4-etienate, the authors prepared 17-hydroxymethyl-4-androsten-3-one and 11-hydroxy-17-hydroxymethyl-4-androsten-3-one. Chlorination of 17-acetoxymethyl-4-androsten-3-one yielded 4-chloro-17-acetoxymethyl-4-androsten-3-one. 17-Hydroxymethyl-1, 4-androstadien-3-one was obtained from 17-hydroxymethyl-4-androsten-3-one, both by chemical and biological methods.