Y.-K. A. Chang

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We have investigated the possibility that structural modifications of the sulfonium analogue of dopamine (4) would produce the same pattern of biological activity as structural modifications of dopamine. A series of methyl- tetralinyl -, and naphthalenylsulfonium analogues 5-7 were prepared and tested for their ability to inhibit the potassium-evoked(More)
In this paper, we study existence of mild solutions for a second order impulsive neutral functional differential equations with state-dependent delay. By using a fixed point theorem for condensing maps combined with theories of a strongly continuous cosine family of bounded linear operators, we prove the main existence theorems. As applications of these(More)
Information regarding the relationship of menopausal hot flushes to menstrual, reproductive and clinical events were obtained from women participating in a case-control study of breast cancer risk. Naturally menopausal women who reported the occurrence of menopausal hot flushes were compared with those without such complaints in an attempt to identify(More)
Paramagnetic alginate beads with a 10-100 microns size range have been developed. These beads, when activated with chloroacetic anhydride and covalently coupled to avidin (30 micrograms/mg beads), were able to bind biotinylated goat anti-mouse (B-GAM) antibody (Ab). The beads with immobilized antibody were then used as a model system for the capture and(More)
Chlorpromazine (1, CPZ) is a potent dopamine antagonist that has been used widely as an antipsychotic agent. Since dopaminergic antagonists, like dopaminergic agonists, exist in solution as the charged and uncharged molecular species, it is not clear which form of the amine is most important for interaction with the dopamine receptor. Previous work from our(More)
Bifunctional silane reagents (3-iodopropyl)trimethoxysilane (1), (gamma-glycidoxypropyl)trimethoxysilane (2), and [1-(trimethoxysilyl)-2-(m- (or p-)chloromethyl)phenyl]ethane (3) were used to covalently link goat anti-mouse (GAM) antibodies (Ab) to glass microbeads and cuprammonium rayon hollow-fiber dialyzers. An average of 0.79 and 0.83 microgram of GAM(More)
Dopamine can exist in both charged and uncharged forms at physiological pH. At present it is unclear which of these forms is responsible for dopaminergic agonist activity. The purpose of this study was to determine whether permanently charged structural analogs of dopamine containing either a nitrogen, sulfur, or selenium atom in the side chain can bind to(More)
The ortho hydroxy/methyl, hydroxy/hydroxymethyl, hydroxy/formyl, and hydroxy/carboxy substitution patterns, some of which confer dopaminergic agonist effects upon 2-aminotetralin ring systems, have been incorporated into beta-phenethylamine, 2-aminoindan, and trans-octahydrobenzo[f]quinoline rings. Certain of the 2-aminoindan derivatives displayed(More)
4-Fluorobenzenesulfonyl chloride (fosyl chloride), due to the strong electron-withdrawing property of its fluoride atom, is found to be an excellent activating agent for the covalent attachment of biologicals to a variety of solid supports (e.g. functionalized polystyrene microspheres, Sepharose beads, or cellulose rods and hollow fibers). This reagent(More)