isthmus


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isthmus

 [is´mus]
a narrow connection between two larger bodies or parts. adj., adj isth´mian.
isthmus of auditory tube (isthmus of eustachian tube) the narrowest part of the eustachian tube at the junction of its bony and cartilaginous parts.
isthmus of fauces (isthmus fau´cium) the constricted aperture between the cavity of the mouth and the pharynx.
isthmus of rhombencephalon the narrow segment of the fetal brain, forming the plane of separation between the rhombencephalon and cerebrum.
isthmus of thyroid the band of tissue joining the lobes of the thyroid.
Isthmus of thyroid gland, connecting the two lobes. From Dorland's, 2000.
isthmus of uterine tube the narrower, thicker-walled portion of the fallopian (uterine) tube closest to the uterus.
isthmus of uterus the constricted part of the uterus between the cervix and the body of the uterus.

isth·mus

, pl.

isth·mi

,

isth·mus·es

(is'mŭs, -mī, -mŭs-ĕz), [TA]
1. A constriction in the embryonic neural tube delineating the anterior portion of the rhombencephalon, the future metencephalon, from the more rostrally located mesenephalon.
[G. isthmos]

isthmus

(ĭs′məs)
n. pl. isth·muses or isth·mi (-mī′)
1. A narrow strip of land connecting two larger masses of land.
2. Anatomy
a. A narrow strip of tissue joining two larger organs or parts of an organ.
b. A narrow passage connecting two larger cavities.

isthmus

A narrow neck or portion of tissue connecting 2 structures.

isth·mus

, pl. isthmi (is'mŭs, -mī) [TA]
1. A constriction connecting two larger parts of an organ or other anatomic structure.
2. A narrow passage connecting two larger cavities.
3. The narrowest portion of the brainstem at the junction between midbrain and hindbrain.
[G. isthmos]
References in periodicals archive ?
Typically, calyces are located in the upper two-thirds of each kidney, but an external calyx or an independent ureter may drain the isthmus (Pawar et al.) (Fig.
But we want to emphasize that on the Karelian Isthmus porous ceramics of the Early Metal Period is very diverse and as in Finland there are yet groups of pottery with no label at all (Mokkonen 2008, 129; Nordkvist & Mekkenen 2015, 155).
Randomized study comparing combined pulmonary vein-left atrial junction disconnection and cavotricuspid isthmus ablation versus pulmonary vein-left atrial junction disconnection alone in patients presenting with typical atrial flutter and atrial fibrillation.
The etiology of isthmus agenesis is also not completely known.
* Division of the isthmus and transplantation of both kidney portions into the same recipient.
Of those roots presenting an isthmus with endoscopy and which were analysed histologically (n=18), an isthmus was present in 12 of the removed apices.
The most common cause of endodontic failure of C-shaped root canals was a leaky canal (45.2%), followed by an isthmus (23.8%), missing canal (9.5%), overfilling (7.1%), and iatrogenic problems (7.1%) (Figure 3, p < 0.05).
Postoperative pathology showed that micropapillary carcinomas scattered around a major thyroid carcinoma (22 x 11 x 20 mm) in thyroid isthmus, and scattered micropapillary carcinoma also existed on both thyroid right lobe and left lobe (Figures 3-5).
The Isthmus of Tehuantepec has long been viewed as a preferred location for a shipping corridor to connect the Pacific and Atlantic oceans, but the only major development in the area in recent years has centered on construction of wind power farms (SourceMex, Oct.
Receiver operating characteristic (ROC) curves were used to determine the threshold of thyroid isthmus length or thyroid volume to predict the success of radioisotope therapy.
Intraoperative findings confirmed the presence of the right lobe and isthmus, the absence of the left lobe, and the presence of a firm nodule with infiltration into the muscle tissue surrounding the site of the absent lobe on the left of the isthmus after abduction of the anterior cervical muscles.
Bu modellerden femur uzunlugu, anteversiyon acisi, collum femoris acisi, isthmus pozisyonu ve proximal femur bolgesinden alinan kesitlerde medio-lateral ve cranio-caudal caplar olculdu.