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multiple sclerosis

(Encyclopedia)multiple sclerosis (MS), chronic, slowly progressive autoimmune disease in which the body's immune system attacks the protective myelin sheaths that surround the nerve cells of the brain and spinal co...

norepinephrine

(Encyclopedia)norepinephrine nôrˌĕpīnĕfˈrən [key], a neurotransmitter in the catecholamine family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous sys...

paralysis

(Encyclopedia)paralysis or palsy pôlˈzē [key], complete loss or impairment of the ability to use voluntary muscles, usually as the result of a disorder of the nervous system. The nervous tissue that is injured m...

smell

(Encyclopedia)smell, sense that enables an organism to perceive and distinguish the odors of various substances, also known as olfaction. In humans, the organ of smell is situated in the mucous membrane of the uppe...

scopolamine

(Encyclopedia)scopolamine hīˈəsēnˌ, –sĭn [key], alkaloid drug obtained from plants of the nightshade family (Solanaceae), chiefly from henbane, Hyoscyamus niger. Structurally similar to the nerve substance ...

Carlsson, Arvid

(Encyclopedia)Carlsson, Arvid, 1923–2018, Swedish pharmacologist, grad. Univ. of Lund, Sweden, (M.D., Ph.D., 1951). Carlsson was a professor at the Univ. of Lund (1951–59) and at the Univ. of Gothenburg, Sweden...

flame

(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...

vacuum

(Encyclopedia)vacuum, theoretically, space without matter in it. A perfect vacuum has never been obtained; the best human-generated vacuums contain less than 100,000 gas molecules per cc, compared to about 30 billi...

diffusion

(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...

Geissler tube

(Encyclopedia)Geissler tube gīsˈlər [key], gas discharge tube in which light is produced when an electric discharge passes through the rarefied gas in the tube. The color of the glow depends on the gas used. The...