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microcentrum

(mīʺkrō-sĕnʹtrŭm) [ʺ + kentron, center] The cytoplasm that contains the centrioles.

microcephalia

(mīʺkrō-sĕf-āʹlē-ă) [ʺ + kephale, head] Microcephaly.

microcephalus

(mīʺkrō-sĕfʹă-lŭs) Individual with an exceptionally small head.

microcephaly

(mīʺkrō-sefʹă-lē) [micro-cephalo-] A birth defect characterized by abnormally small development of the brain and head. It is typically defined as having a head circumference that is at least 2 standard deviations (SD) below the normal size for age although many authorities reserve the designation for children with heads that are 3 SD below normal. It is often accompanied by developmental delays and cognitive disability, seizures, and other neurological problems. It is sometimes caused by viral infections of the mother during pregnancy, e.g., by infections with cytomegalovirus, rubella, or Zika virus. Particular microcephalies are listed under the first word.

image Norms for head circumference vary between different ethnic and geographic populations; they cannot be universally applied.

 SEE: Amish lethal microcephaly. microcephalic, microcephalous (mīʺkrō-sĕ-falʹik, mīʺkrō-sefʹă-lŭs), adj.

microchemistry

(mīʺkrō-kĕmʹĭs-trē) [ʺ + chemeia, chemistry] Branch of chemistry analyzing specimens of minute quantity.

microchimerism

(mīʺkrō-kī-mĭrʹĭ-zĭm, kīʹmĭ-rĭzʺĭm) [ʺ + ʺ] The presence in a tissue of some cells of alien origin, e.g., of fetal cells in a pregnant woman’s bloodstream.

microcinematography

(mīʺkrō-sĭnʺĕ-mă-tŏgʹră-fē) [ʺ + kinema, motion, + graphein, to write] Motion pictures of microscopic objects.

microcirculation

(mīʺkrō-sĭrʺkū-lāʹshŭn) Blood flow in the very small vessels (arterioles, capillaries, and venules). microcirculatory, adj.

Micrococcaceae

(mīʺkrō-kŏk-āʹsē-ē) A family of gram-positive cocci that includes the genera Acaricomes, Arthrobacter, Citricoccus, Kocuria, Micrococcus, Nesterenkonia, Renibacterium, Rothia, Sinomonas, Stomatococcus, and Zhihengliuella.

Micrococcus

(mīʺkrō-kŏkʹŭs) [Gr. mikros, small, + kokkos, berry] A genus of gram-positive cocci; species are saprophytes found throughout the environment.

micrococcus

(mīʺkrō-kŏkʹŭs) pl. micrococci An organism of the genus Micrococcus.

microcolon

(mīʹkrō-kōʺlŏn) Abnormally small colon.

microcoria

(mīʺkrō-kōʹrē-ă) [ʺ + kore, pupil] Smallness of the pupil of the eye.

microcornea

(mīʺkrō-kŏrʹnē-ă) Abnormally small cornea.

microcoulomb

(mīʺkrō-kooʹlŏm) A microunit of current electricity; one-millionth part (10–6) of a coulomb.

microcrystalline

(mīʺkrō-krĭsʹtăl-īn, -ēn) Composed of microscopic crystals.

microcurie

ABBR: µCi. One millionth of a curie.

microcyst

(mīʹkrō-sĭst) A very small cyst.

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