Rough, scaly patches of skin that are considered precancerous and are due to sun exposure. Prevention is to cut sun exposure and wear sunscreen. Treatments include performing cryosurgery (freezing with liquid nitrogen), cutting the keratoses away, burning them, putting 5-fluorouracil on them, and using photodynamic therapy (injecting into the bloodstream a chemical that collects in actinic keratoses and makes them more sensitive to destruction by a specialized form of light). Also known as solar keratosis and senile keratosis.
Actinomycetes: A group of gram-positive bacteria (order Actinomycetales) that produce various bioactive agents including antibiotics, enzymes, and vitamins. Streptomyces belong to this bacterial order.
- Activated charcoal
Activated charcoal: Charcoal that has been heated to increase its ability to absorb molecules. Activated charcoal is used to help relieve intestinal gas. It is also used to filter and purify liquids, to absorb poisons (as in gas mask filters), and in emergency situations to neutralize swallowed poisons.
- Active euthanasia
Active euthanasia: The active acceleration of a “good” death by use of drugs etc, whether by oneself or with the aid of a doctor. The word “euthanasia” comes from the Greek — “eu” meaning “goodly or well” + “thanatos” meaning “death.” So, euthanasia is literally the “good death.” In 18th-century England, that was what euthanasia […]
- Active immunity
Active immunity: Immunity produced by the body in response to stimulation by a disease-causing organism or other agent.
- Activities of daily living (ADLs)
Activities of daily living (ADLs): The things we normally do in daily living including any daily activity we perform for self-care such as feeding ourselves, bathing, dressing, grooming, work, homemaking, and leisure. The ability or inability to perform ADLs can be used as a very practical measure of ability/disability in many disorders.