| fibrous sheaths | See: fibrous tendon sheath, fibrous digital sheaths of hand, fibrous digital sheaths of foot. (05 Mar 2000) |
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| fibrous skeleton of heart | A complex framework of dense collagen forming four fibrous rings (annuli fibrosi), which surround the ostia of the valves, a right and left fibrous trigone, formed by connecting the rings, and the membranous portions of the interatrial and interventricular septa; it is found in association with the base of the ventricles, i.e., at the level of the coronary sulcus; its functions include: 1) contributing reinforcement of the valvular ostia while providing attachment for the leaflets and cusps of the valves; 2) providing origin and insertion for the myocardium; and 3) serving as a sort of electrical "insulator," separating the electrically conducted impulses of the atria and ventricles and providing passage for the common atrioventricular bundle of conductive tissue through the right fibrous trigone and membranous interventricular septum. Synonym: cardiac fibrous skeleton, cardiac skeleton, skeleton of heart. (05 Mar 2000) |
| fibrous tissue | Although most connective tissue has fibrillar elements, the term usually refers to tissue laid down at a wound site well vascularised at first (granulation tissue) but later avascular and dominated by collagen rich extracellular matrix, forming a scar. Excessive contraction and hyperplasia leads to formation of a keloid. (18 Nov 1997) |
| fibrous trigones of heart | See: right fibrous trigone, left fibrous trigone. (05 Mar 2000) |
| fibrous tubercle | A tubercle in which fibroblasts proliferate about the periphery (and into the cellular zones), eventually resulting in a rim or wall of cellular fibrous tissue or collagenous material around the tubercle. (05 Mar 2000) |
| fibrous tunic of corpus spongiosum | <anatomy> The thick layer of fibrous tissue surrounding the corpus spongiosum penis. It is thinner than the corresponding layer around each corpus cavernosum. Synonym: tunica albuginea corporis spongiosi, fibrous tunic of corpus spongiosum. (05 Mar 2000) |
| fibrous tunic of eye | The outer layer of the eyeball composed of the sclera and cornea. Synonym: tunica fibrosa bulbi, tunica externa oculi. (05 Mar 2000) |
| fibrous union | Union of fracture by fibrous tissue. See: nonunion. Synonym: faulty union. (05 Mar 2000) |
| fibrous xanthoma | <tumour> A fibrohistiocytic neoplasm. (05 Mar 2000) |
| left fibrous trigone | The part of the fibrous skeleton of the heart located in the interval between the left side of the left atrioventricular ring and the aortic ring. Synonym: trigonum fibrosum sinistrum. (05 Mar 2000) |
| accessory thyroid | An isolated mass, or one of several such masses, of thyroid tissue, sometimes present in the side of the neck, or just above the hyoid bone (suprahyoid accessory thyroid gland), or even as low as the arch of the aorta. Synonym: glandula thyroidea accessoria, accessory thyroid, prehyoid gland, suprahyoid gland, thyroidea accessoria, thyroidea ima, Wolfler's gland. (05 Mar 2000) |
| anaplastic carcinoma of the thyroid | <oncology, tumour> An aggressive form and rare form of thyroid cancer that is one of the most rapidly growing and invasive types of thyroid cancer. It commonly occurs in people over 60 years of age and may cause obstruction of the trachea. The cause is unknown but exposure to radiation may be a factor. Thyroid function tests are usually normal. Hoarse voice, cough and coughing up blood are common symptoms. Examination may reveal nodules in the thyroid gland. Diagnosis is made via biopsy. Treatment is surgical with or without radiation therapy. (27 Sep 1997) |
| cancer, thyroid | Cancer of the gland in front of the neck that normally produces thyroid hormone which is important to the normal regulation of the metabolism of the body. There are four major types of cancer of the thyroid gland. Persons who received radiation to the head or neck in childhood should be examined by a doctor every 1 to 2 years. The most common symptom of thyroid cancer is a lump, or nodule, that can be felt in the neck. The only certain way to tell whether a thyroid lump is cancer is by examining the thyroid tissue obtained using a needle or surgery for biopsy. (12 Dec 1998) |
| receptors, thyroid hormone | Proteins, usually found in the nucleus, that specifically bind thyroid hormones and regulate DNA transcription. These proteins, termed c-erba, are activated by hormones and cause differentiation of erythroid progenitor cells which irreversibly lose proliferative potential. Thus c-erba proteins act as growth suppressors. The c-erba proteins are encoded by at least two genes, c-erba alpha and c-erba beta. Each of these has two isoforms. Mutations in the ligand-binding domain of the beta form causes thyroid hormone resistance syndrome. (12 Dec 1998) |
| glandular branches of inferior thyroid artery | <anatomy, artery> Branches of inferior thyroid artery to thyroid and parathyroid glands, anastomosing with branches of superior thyroid artery. Synonym: rami glandulares arteriae thyroideae inferioris. (05 Mar 2000) |