摘要:
Compounds of the formula where the symbols have the meaning described in the application, have retinoid-like or retinoid antagonist-like biological activity.
摘要:
Compounds of the formula where the symbols have the meaning described in the application, have retinoid-like or retinoid antagonist-like biological activity.
摘要:
Retinoid compounds which act specifically or selectively on RAR&agr; receptor subtypes in preference over RAR&bgr; and RAR&Ggr; receptor subtypes, possess desirable pharmaceutical properties associated with retinoids, and are particularly suitable for treatment of tumors, such as acute monocytic leukemia, cervical carcinoma, myeloma, ovarian carcinomas and head and neck carcinomas, without having one or more undesirable side effects of retinoids, such as inducement of weight loss, mucocutaneous toxicity, skin irritation and teratogenecity.
摘要:
2,2-Dialkyl-4-aryl-substituted benzopyran and benzothiopyran derivatives of the formula ##STR1## where the symbols have the meaning described in the specification, have retinoid negative hormone and/or antagonist-like biological activities. The invented RAR antagonists can be administered to mammals, including humans, for the purpose of preventing or diminishing action of RAR agonists on the bound receptor sites. Specifically, the RAR agonists are administered or coadministered with retinoid drugs to prevent or ameliorate toxicity or side effects caused by retinoids or vitamin A or vitamin A precursors. The retinoid negative hormones can be used to potentiate the activities of other retinoids and nuclear receptor agonists.
摘要:
Compounds of the formula ##STR1## where the symbols have the meaning described in the application, have retinoid-like or retinoid antagonist-like biological activity.
摘要:
A semiconductor photonic device includes a substrate, facet(s), and optical coupler(s) associated with the facet(s). Each optical coupler can couple an electromagnetic field incident on the respective facet towards a buried waveguide as the electromagnetic field proceeds into the semiconductor photonic device. In some examples, each coupler has waveguides extending in a longitudinal direction and at least partly encapsulated within a cladding layer. In some examples, at least one waveguide tapers along its length. In some examples, at least one waveguide includes spaced-apart segments arranged to form a subwavelength grating (SWG) configured to entrain electromagnetic radiation.
摘要:
A semiconductor photonic device includes a substrate, facet(s), and optical coupler(s) associated with the facet(s). Each optical coupler can couple an electromagnetic field incident on the respective facet towards the substrate as the electromagnetic field proceeds into the semiconductor photonic device. In some examples, each coupler has waveguides extending in a longitudinal direction and at least partly encapsulated within corresponding cladding layers. A first waveguide extends farther from the facet in the longitudinal direction than does a second waveguide. The second waveguide is located farther above the silicon substrate than is the first waveguide. The coupler can include a stack of waveguide assemblies. A lower waveguide assembly can include one waveguide. An intermediate or upper waveguide assembly can include multiple waveguides. In some examples, at least one waveguide tapers along its length.