Y.-K. A. Chang

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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)
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)
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)
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)
The purpose of this study was to determine if structural analogs of dopamine in which the side chain nitrogen has been replaced by a permanently uncharged monomethylsulfide, monomethylselenide or sulfoxide group are capable of binding to the striatal D-2 dopamine receptor and acting as agonists at this receptor. All the permanently uncharged dopamine(More)
The effects of chemical analogs of dopamine, which are permanently charged or which lack a net positive charge, on the potassium-evoked release of [3H]acetylcholine from mouse striatal slices were studied in order to determine whether a positive charge on the dopamine agonist molecule is required to activate dopaminergic receptors. The striatal slices were(More)