physical material that has form and weight; called also matter
2. the material constituting an organ or body.
substance Abuse and Mental Health Services Administration
(SAMHSA) an agency of the United States Department of Health and Human Services, created in 1992 to oversee the quality and availability of programs for prevention, treatment, and rehabilitation of substance abuse
and related mental health problems.
ground substance the gel-like material in which connective tissue cells and fibers are embedded.
a subgroup of the substance-related disorders
comprising a variety of behavioral or psychological anomalies resulting from ingestion of or exposure to a drug of abuse, medication, or toxin. Included are substance intoxication, substance withdrawal, and other mental disorders such as dementia, mood disorder, and psychotic disorder when they are specifically caused by a substance. See also substance use disorders
1. the white matter of the central nervous system, consisting of axons and their myelin sheaths.
2. the soft, marrow-like substance of the interior of such structures as bone, kidney, and adrenal gland.
müllerian inhibiting substance a glycoprotein produced by the Sertoli cells of the fetal testis that acts ipsilaterally in the male to suppress the müllerian ducts, consequently preventing development of the uterus and fallopian tubes, thus helping to control formation of the male phenotype.
substance P a peptide composed of 11 amino acids, present in nerve cells scattered throughout the body and in special endocrine cells in the gut; it increases the contractions of gastrointestinal smooth muscle and causes vasodilatation; it is one of the most potent vasoactive substances known, and it seems to be a sensory neurotransmitter involving pain, touch, and temperature.
1. anterior perforated substance, an area anterolateral to each optic tract, pierced by branches of the anterior and middle cerebral arteries.
2. posterior perforated substance, an area between the cerebral peduncles, pierced by branches of the posterior cerebral arteries.
) any chemical compound that affects the mind or mental processes, particularly a drug used therapeutically in psychiatry, or any of various other types of mind-altering substances such as drugs of abuse and some toxins. See also table at drug dependence
. Called also psychoactive agent or drug and psychotropic agent or drug.
There are several different classes of psychoactive substances: antidepressants
are used for the relief of symptoms of major depression. lithium
is the most common agent used to treat manic episodes of bipolar disorder
. antipsychotic agents
(or major tranquilizers) are used for management of the manifestations of psychotic disorders such as schizophrenia
. antianxiety agents
(called also minor tranquilizers), such as diazepam
), are used for relief of anxiety disorders. While none of these drugs can effect a cure, they can reduce the severity of symptoms and permit the patient to resume more normal activity.
Also included in the category of psychotropic drugs are many other substances that affect the mind but are not used to treat mental disorders, including stimulants
such as caffeine
, and cocaine
; and hallucinogens
any of the mental disorders associated with excessive use of or exposure to psychoactive substances, including drugs of abuse, medications, and toxins. The group is divided into substance use disorders
and substance-induced disorders
, each of which is specified on the basis of etiology, such as alcohol use disorders. See also drug abuse
and drug dependence
slow-reacting substance of anaphylaxis SRS-A, an inflammatory agent released by mast cells in the anaphylactic reaction. It induces slow, prolonged contraction of certain smooth muscles and is an important mediator of allergic bronchial asthma.
those substances in the blood, such as glucose, that are excreted when they reach their renal threshold
substance use disorders
a subgroup of the substance-related disorders
, in which psychoactive substance
use or abuse repeatedly results in significantly adverse consequences. The group comprises substance abuse (see drug abuse
) and substance dependence (see drug dependence
); specific disorders or groups of disorders are named on the basis of etiology, e.g., alcohol use disorders, alcohol abuse, and alcohol dependence.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
Patient discussion about substance
Q. What exactly is PPD? I heard it is a substance in hair color and that some women are allergic to it How can I know if I’m allergic to it?
A. That sounds nasty... so how can I know if i'm allergic to it or not?
Q. What are the bases of Chinese medicine? what substances make chinese medicine so effective according to people's opinion ...
A. good question...
because chinese medicine is a popular medicine and practiced in different rural areas of China- there is a lot of diversity between different methods. different feet maps for reflexology, different opinions on acupuncture points and such. but the general idea is the same. and believe it or not - the chinese medicine is actually a trial and error based method that developed over 4,000 years.
that is a lot of time to do trial and error...
Q. Can anybody tell me the point where I should be worried that I've become an alcoholoic? What is the definition of an alcoholist?
A. You truly have a great site here. Its got a lot of potential and can surely help many. More discussions about substance
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