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body

 [bod´e]
trunk (def. 1).
1. the largest and most important part of any organ.
2. any mass or collection of material.
acetone b's ketone bodies.
alkapton b's a class of substances with an affinity for alkali, found in the urine and causing the condition known as alkaptonuria. The compound commonly found, and most commonly referred to by the term, is homogentisic acid.
amygdaloid body a small mass of subcortical gray matter within the tip of the temporal lobe, anterior to the inferior horn of the lateral ventricle of the brain. It is part of the limbic system.
aortic b's small neurovascular structures on either side of the aorta in the region of the aortic arch, containing chemoreceptors that play a role in reflex regulation of respiration.
asbestos b's golden yellow bodies of various shapes, formed by the deposition of calcium salts, iron salts, and proteins on a spicule of asbestos, found in the lungs, lung secretions, and feces of patients with asbestosis.
Aschoff b's submiliary collections of cells and leukocytes in the interstitial tissues of the heart in the myocarditis that accompanies rheumatic fever; called also Aschoff's nodules.
asteroid body an irregularly star-shaped inclusion body found in the giant cells in sarcoidosis and other diseases.
Babès-Ernst body metachromatic granule.
Barr body sex chromatin.
basal body a modified centriole that occurs at the base of a flagellum or cilium.
carotid b's small neurovascular structures lying in the bifurcation of the right and left carotid arteries, containing chemoreceptors that monitor the oxygen content of the blood and help to regulate respiration.
ciliary body see ciliary body.
Donovan b's encapsulated bacteria (Calymmatobacterium granulomatis) found in lesions of granuloma inguinale, visible when a Wright-stained smear of infected tissue is viewed under a microscope.
body dysmorphic disorder a somatoform disorder in which a normal-appearing person is either preoccupied with an imagined defect in appearance or is overly concerned about a very slight physical anomaly. See also body image. Called also dysmorphophobia.
fimbriate body corpus fimbriatum.
foreign body a mass of material that is not normal to the place where it is found.
fruiting body a specialized structure of certain fungi that produces the spores.
geniculate body, lateral either of the two metathalamus eminences, one on each side just lateral to the medial geniculate bodies, marking the termination of the optic tract.
geniculate body, medial either of the two metathalamus eminences, one on each side just lateral to the superior colliculi, concerned with hearing.
hematoxylin body a dense, homogeneous particle, easily stainable with hematoxylin, consisting of nuclear material derived from an injured cell together with a small amount of cytoplasm. Hematoxylin bodies occur in systemic lupus erythematosus. Lymphocytes that ingest such particles are known as le cells. Called also LE body.
Howell's b's (Howell-Jolly b's) smooth, round remnants of nuclear chromatin seen in erythrocytes in megaloblastic and hemolytic anemia, in various leukemias and after splenectomy.
body image the total concept, including conscious and unconscious feelings, thoughts, and perceptions, that a person has of his or her own body as an object in space independent and apart from other objects. The body image develops during infancy and childhood from exploration of the body surface and orifices, from development of physical abilities, and from play and comparison of the self with others. Changes in body image are particularly important in adolescence when attention is focused on appearance and attractiveness and relations with others. Body image is strongly influenced by parental attitudes that give the child a perception of certain body parts as good, clean, and attractive, or bad, dirty, and repulsive. The evolution of body image continues throughout life and incorporates such factors as a person's style of dress, hair style, and use of makeup, which symbolize social and professional status and other feelings about the self.

Many clinical syndromes involve disturbances of body image. Disturbed body image is a nursing diagnosis that was approved by the North American Nursing Diagnosis Association, defined as confusion in the mental picture of one's physical self. Surgery or trauma involving disfigurement or loss of a body part can be very threatening to a patient. Diseases involving a loss of body function, such as stroke syndrome, paraplegia, quadriplegia, coronary heart disease, and bowel or bladder incontinence, and diseases involving disfiguring skin lesions or the feeling of “rotting away” as in cancer or gangrene, can all cause changes in body image. Body image is frequently disturbed in schizophrenia, and patients may feel that their body or its parts are changing in size or shape or are ugly or threatening. Rape or violent physical assault can disturb the feeling of being secure in one's own body. Changes in body image involving sexual attractiveness or sexual identity, such as surgery or trauma involving the genitals or breasts and tubal ligation, hysterectomy, or vasectomy, can be especially difficult for the patient to deal with. Intrusive therapeutic or diagnostic procedures, such as insertion of a nasogastric tube, bladder catheterization, administration of intravenous fluids, endoscopy, and cardiac catheterization, can also threaten a patient's body image.

The reaction of a patient to an alteration in body image can include mourning the loss of the former body image, fear of rejection by significant others, hostility, and experiencing of “phantom” sensations from missing body parts. Patients with less ability to cope with their loss may respond with denial or depression. This can lead to a rejection of the altered body image and feelings of depersonalization that can involve avoidance of interpersonal contact and an unwillingness to discuss the deformity or to accept corrective medical treatment or vocational rehabilitation.
inclusion b's round, oval, or irregular-shaped bodies in the cytoplasm and nuclei of cells, as in disease caused by viral infection, such as rabies, smallpox, and herpes.
ketone b's see ketone bodies.
lamellar body keratinosome.
Lafora's b's intracytoplasmic inclusions consisting of a complex of glycoprotein and acid mucopolysaccharide; widespread deposits are found in Lafora's disease, a type of epilepsy.
Leishman-Donovan b's round or oval bodies found in the reticuloendothelial cells, especially those of the spleen and liver, in kala-azar; they are nonflagellate intracellular forms of Leishmania donovani. Also used to designate similar forms of Leishmania tropica found in macrophages in lesions of cutaneous leishmaniasis.
mamillary body (mammillary body) either of the pair of small spherical masses in the interpeduncular fossa of the midbrain, forming part of the hypothalamus.
Masson b's cellular tissue that fills the pulmonary alveoli and alveolar ducts in rheumatic pneumonia; they may be modified Aschoff's bodies.
molluscum b's large homogeneous intracytoplasmic inclusions found in the stratum granulosum and stratum corneum in molluscum contagiosum, which contain replicating virus particles and cellular debris.
multilamellar body any of the osmiophilic, lipid-rich, layered bodies found in the great alveolar cells of the lung.
Negri b's oval or round bodies in the nerve cells of animals dead of rabies.
Nissl b's large granular bodies that stain with basic dyes, forming the reticular substance of the cytoplasm of neurons, composed of rough endoplasmic reticulum and free polyribosomes; ribonucleoprotein is one of their main constituents. Called also Nissl's granules.
olivary body olive (def. 2).
paraaortic b's see para-aortic bodies.
pineal body see pineal body.
pituitary body pituitary gland.
polar b's
1. the small cells consisting of a tiny bit of cytoplasm and a nucleus; they result from unequal division of the primary oocyte (first polar body) and, if fertilization occurs, of the secondary oocyte (second polar body).
2. metachromatic granules located at one or both ends of a bacterial cell.
psammoma b's usually microscopic, laminated masses of calcareous material, occurring in both benign and malignant epithelial and connective-tissue tumors, and sometimes associated with chronic inflammation.
quadrigeminal b's corpora quadrigemina.
body of sternum the second or main part of the sternum, bounded by the manubrium above and the xiphoid process below. Called also gladiolus and corpus sterni.
striate body corpus striatum.
trachoma b's inclusion bodies found in clusters in the cytoplasm of the epithelial cells of the conjunctiva in trachoma.
vitreous body the transparent gel filling the inner portion of the eyeball between the lens and retina. Called also vitreous and vitreous humor.
wolffian body mesonephros.

Barr body

(bär)
n.
The condensed, inactive X chromosome found in the nuclei of somatic cells of most female mammals. Also called sex chromatin.

Barr body

Barr body

A condensed clump of chromatin that corresponds to an inactivated X chromosome, which is located next to the nuclear membrane, and best seen in somatic cells in interphase. The number of BBs per cell is 1 less than the number of X chromosomes, thus normal XX women cells will have one BB, as do men with 47 XXY (Klinefelter syndrome). Normal XY males have none, nor do 45 XO (Turner syndrome) females.

Barr body

A condensed clump of CHROMATIN occurring in the nucleus of cells in normal females and corresponding to an inactive X chromosome. The Barr body also occurs in males with two or more X chromosomes an addition to the Y chromosome. See also X-INACTIVATION. (Murray Llewellyn Barr, Canadian anatomist, 1908–95).
Barr bodyclick for a larger image
Fig. 61 Barr body . Sex chromatin in nuclei from human male and female buccal epithelial cells.

Barr body

a sex CHROMATIN particle found in the interphase nucleus of buccal epithelial cells in some female mammals and probably derived from an X-chromosome (see INACTIVE-X HYPOTHESIS). first described by Murray Barr in 1949, Barr bodies can be used as a sex marker, always occurring in numbers one less than the total number of X-chromosomes. Thus buccal cells of normal human males and TURNERS SYNDROME females have no Barr bodies, cells of normal females have one, whilst cells of KLINEFELTER'S SYNDROME males have two.

Barr,

Murray Liewellyn, Canadian microanatomist, 1908–.
Barr body - Synonym(s): Barr chromatin body
Barr chromatin body - a small condensed mass of the inactivated X-chromosome usually located just inside the nuclear membrane of the interphase nucleus. Synonym(s): Barr body; sex chromatin

Barr body

a small mass of densely staining chromatin seen during interphase of female cells produced by condensation of one of the two X chromosomes. See also drumstick.
References in periodicals archive ?
He said he had not made any unreasonable demands as is being alleged by the bar body.