diaphragm

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diaphragm

 [di´ah-fram]
1. the musculomembranous partition separating the thoracic and abdominal cavities. On its sides it is attached to the six lower ribs, at its front to the sternum, and at its back to the spine. The esophagus, aorta, vena cava, and numerous nerves pass through the diaphragm. When relaxed it is convex, but it flattens as it contracts during inhalation, thereby enlarging the chest cavity and allowing for expansion of the lungs. See also respiration.
2. any separating membrane or structure.
3. a disk with one or more openings or with an adjustable opening, mounted in relation to a lens or source of radiation, by which part of the light or radiation may be excluded from the area.
contraceptive diaphragm a shallow dome-shaped disk used as a contraceptive, made of a soft plastic material such as latex. Its anterior lip fits behind the symphysis pubis and its posterior lip rests in the posterior fornix. It is used with a spermicide to prevent entrance of spermatozoa into the cervical os. See also contraception.
pelvic diaphragm the portion of the floor of the pelvis formed by the coccygeus muscles and the levator ani muscles, and their fascia.
polyarcuate diaphragm one showing abnormal scalloping of margins on radiographic visualization.
urogenital diaphragm a traditional but no longer valid concept that superior and inferior layers enclose the sphincter urethrae and deep transverse perineal muscles and together form a musculomembranous sheet that extends between the ischiopubic rami.
vaginal diaphragm contraceptive diaphragm.

di·a·phragm

(dī'ă-fram),
1. The musculomembranous partition between the abdominal and thoracic cavities. Synonym(s): diaphragma (2) , interseptum, midriff, phren (1)
2. A thin disc pierced with an opening, used in a microscope, camera, or other optic instrument to shut out the marginal rays of light, thus giving a more direct illumination.
3. A flexible ring covered with a domed sheet of elastic material used in the vagina to prevent pregnancy.
4. In radiography, a grid (2) or a lead sheet with an aperture.
[G. diaphragma]

diaphragm

(dī′ə-frăm′)
n.
1. Anatomy A muscular membranous partition separating the abdominal and thoracic cavities and functioning in respiration. Also called midriff.
2. A membranous part that divides or separates.
3. A thin disk, especially in a microphone or telephone receiver, that vibrates in response to sound waves to produce electric signals, or that vibrates in response to electric signals to produce sound waves.
4. A contraceptive device consisting of a thin flexible disk, usually made of rubber, that is designed to cover the uterine cervix to prevent the entry of sperm during sexual intercourse.
5. A disk having a fixed or variable opening used to restrict the amount of light traversing a lens or optical system.

di′a·phrag·mat′ic (-frăg-măt′ĭk) adj.
di′a·phrag·mat′i·cal·ly adv.

diaphragm

A contraceptive device consisting of a thin membranous disk, typically constructed of rubber, which is designed to cover the cervical os and prevent the entry of sperm during sexual intercourse.

diaphragm

Gynecology A barrier contraceptive consisting of a thin flexible rubber disk that covers the uterine cervix to prevent the entry of sperm during sexual intercourse

di·a·phragm

(dī'ă-fram) [TA]
1. The musculomembranous partition between the abdominal and thoracic cavities.
Synonym(s): diaphragma (2) [TA] , midriff.
2. A thin disc pierced with an opening, used in a microscope, camera, or other optic instrument to shut out the marginal rays of light, thus giving a more direct illumination.
3. A flexible ring covered with a dome-shaped sheet of elastic material placed in the vagina to prevent pregnancy.
4. radiography A grid (2).
[G. diaphragma]

diaphragm

(di'a-fram?) [Gr. diaphragma, a partition]
1. A thin membrane as is used for dialysis.
2. In microscopy, an apparatus located beneath the opening in the stage and permitting regulation of the amount of light passing through the object.
Enlarge picture
CONTRACEPTIVE DIAPHRAGM
3. A rubber or plastic cup that fits over the cervix uteri, used for contraceptive purposes. See: illustration
Enlarge picture
MOVEMENT OF RIB CAGE AND DIAPHRAGM DURING RESPIRATION: A. Inspiration: Air drawn into lungs; B. Expiration: Air forced out of lungs
4. The dome-shaped skeletal muscle that separates the abdomen from the thoracic cavity with its convexity upward. It contracts to promote inhalation, flattening downward and permitting the lungs to expand. It relaxes to promote exhalation, rising to its dome-shaped position and compressing the lungs.

The origin of the diaphragm is the xiphoid process, the lower six costal cartilages, and the lumbar vertebrae. The diaphragm is directly superior to the liver, the stomach, the spleen, the adrenal glands, and the kidneys; the right side is slightly higher than the left. See: illustration; Boerhaave syndrome

Bucky diaphragm

See: Bucky, Gustav P.

hernia of diaphragm

A congenital or traumatic protrusion of abdominal contents through the diaphragm.

pelvic diaphragm

Pelvic floor.

Potter-Bucky diaphragm

Bucky diaphragm.

slit diaphragm

A gap between the foot processes of podocytes in the renal glomerulus, composed of a filter made of proteins that holds large molecules within the plasma but allows smaller soluble chemicals to pass with water into the urine.

urogenital diaphragm

The urogenital trigone, or triangular ligament. A musculofascial sheath that lies between the ischiopubic rami, it is superficial to the pelvic diaphragm. In males it surrounds the membranous urethra; in females, the vagina.
illustration

diaphragm

1. The dome-shaped muscular and tendinous partition that separates the cavity of the chest from the cavity of the abdomen. When the muscle contracts the dome flattens, thereby increasing the volume of the chest.
2. Any partitioning structure, such as the iris diaphragm of the eye.

diaphragm

  1. a sheet of tissue present only in mammals, that separates the thorax from the abdomen. It consists mainly of muscle and tendons, and has openings through which the oesophagus, blood vessels and nerves pass. Its flattening from a convex position projecting into the thorax is an important aspect of the expansion of the lungs as inspiration takes place. See BREATHING.
  2. a hemispherical rubber cap fitted inside the vagina over the neck (cervix) of the uterus and acting as a contraceptive for BIRTH CONTROL.

Diaphragm

The thin layer of muscle that separates the chest cavity containing the lungs and heart from the abdominal cavity containing the intestines and digestive organs.

diaphragm

1. In optics, an aperture generally round and of variable diameter placed in a screen and used to limit the field of view of a lens or optical system (field stop). It also limits stray light (light stop). Syn. stop; aperture-stop. 2. In anatomy, a dividing membrane.

di·a·phragm

(dī'ă-fram) [TA]
1. [TA] Musculomembranous partition between abdominal thoracic cavities.
2. In radiography, a grid (2) or a lead sheet with an aperture.
See: collimator
3. A thin disc pierced with an opening, used in a microscope, camera, or other optic instrument to shut out the marginal rays of light, thus giving a more direct illumination.
[G. diaphragma]