parathyroid glands


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parathyroid

 [par″ah-thi´roid]
1. near the thyroid gland.
2. a parathyroid gland.
3. a preparation containing parathyroid hormone from animal parathyroid glands; used for diagnosis and treatment of hypoparathyroidism.
parathyroid glands four small endocrine bodies in the region of the thyroid gland; they contain two types of cells: chief cells and oxyphils. Chief cells are the major source of parathyroid hormone (PTH), the secretion of which is dependent on the serum calcium level. Through a closed-loop feedback mechanism a low serum calcium level stimulates secretion of PTH; conversely, a high serum calcium level inhibits its secretion. The essential role of PTH is maintenance of a normal serum calcium level in association with vitamin D and calcitonin. It does this by exerting its effects on bone, kidney, and gastrointestinal tract. In bone, it enhances bone resorption by increasing digestion of the bone matrix by osteoclasts, which produces calcium that gets released into the bloodstream. In the kidney, PTH increases the excretion of phosphate and the reabsorption of filtered calcium. In the intestine, it increases intestinal absorption of calcium. The parathyroid glands may be subject to either hyperparathyroidism or hypoparathyroidism.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

parathyroid glands

Four, yellow, bean-shaped bodies, each about 0.5 cm long, lying behind the THYROID GLAND, usually embedded in its capsule. The parathyroids secrete a hormone, parathyroid hormone (parathormone or PTH), into the blood if the level of calcium in the blood drops. This hormone promotes the release of calcium from the bones, controls loss in the urine and increases absorption from the intestine, thus correcting the deficiency in the blood. Maintenance of accurate levels of blood calcium is more important, physiologically, than the strength of the bones. Secretion of abnormal quantities of PTH from a parathyroid tumour can lead to bone softening. Underaction of the parathyroids causes a dangerous drop in the blood calcium.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

Sandström,

Ivor V., swedish anatomist, 1852-1889.
Sandström bodies - Synonym(s): parathyroid glands
Medical Eponyms © Farlex 2012
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References in periodicals archive ?
It has been noted that when all four parathyroid glands were preserved per-operatively, only 5 patients (11.9%) developed transient hypocalcaemia, no patients developed permanent hypocalcaemia and 15 patients (35.7%) did not develop any symptoms of hypocalcaemia.
FACTORS CONTRIBUTING TO POST-OPERATIVE HYPOCALCAEMIA AFTER TOTAL THYROIDECTOMY-EXPERIENCE IN A TERTIARY CARE GOVT. HOSPITAL IN EASTERN INDIA
Radionuclide imaging of the parathyroid glands. Semin Nucl Med 2005; 35: 266-76.
Diagnostic Value of Ultrasound and Tc-99m MIBI scintigraphy and SPECT/CT for Pre-operative Localization of Parathyroid Adenoma in Patients with Primary Hyperparathyroidism: A Single-Center Comparative Study/Operasyon Oncesi Paratiroid Adenomlarinin Yerini Saptamada Ultrason ve Tc-99m MIBI sintigrafisi ve SPECT/CT Incelemenin Tanisal Degeri
A number of scintigraphic methods were improved for preoperative pinpoint of hyperfunctional parathyroid glands in the past decade.
Ectopic and Eutopic Located Parathyroid Lesions: Do They Behave Differently? How Can We Monitor Them? What Should We Look for?
Number of parathyroid glands or inadvertently excised were not analysed due to small numbers in subgroups.
Frequency of Hypocalcaemia following Total Thyroidectomy
MIBI scan, CT, MRI, and venous blood sampling), more ectopic parathyroid glands can be detected in patients with hyperparathyroidism symptoms (10).
Robot-assisted endoscopic mediastinal parathyroidectomy
A parathyroid gland is considered to be enlarged if it measures greater than 5-7 mm long, 1-2 mm thick and 3-4 mm wide.
Sonar guided focused parathyroidectomy under cervical block
The parathyroid gland is the overall regulatory organ that maintains calcium homeostasis through their capacity to sense even minute changes in the level of blood calcium.
Primary hyperparathyroidism and Gougerot disease
Caption: Figure 2: Microscopic finding from the parathyroid glands. (a) Right inferior paratiroid hyperplasia (H&E stain).
Spontaneous and Excellent Healing of Bilateral Brown Tumors in Mandible after Endocrinal Therapy and Subtotal Parathyroidectomy: Case Report with 4-Year Follow-Up
Speck et al., "Altered parathyroid gland function in severely immunocompromised patients infected with human immunodeficiency virus," The Journal of Clinical Endocrinology & Metabolism, vol.
Severe Symptomatic Hypocalcemia from HIV Related Hypoparathyroidism
Myschetzky, "Preoperative localization of hyperfunctioning parathyroid glands with 4D-CT," European Archives of OtoRhino-Laryngology, vol.
Craniofacial Brown Tumor in Patients with Secondary Hyperparathyroidism to Chronic Renal Failure: Report of Two Cases in Cipto Mangunkusumo Hospital
Among the etiology of pHPT, the parathyroid adenoma is the most frequent cause (80%) followed by other pathologies such as endocrine disorders of multiple neoplasia (MEN 1 and MEN 2A), hyperplasia of the parathyroid glands, or even carcinoma (1%) [3].
Primary Hyperparathyroidism due to Parathyroid Adenoma Originated from Supernumerary Gland
Tisell, "Autotransplantation of diseased parathyroid glands into subcutaneous abdominal adipose tissue," Surgery, vol.
Total Parathyroidectomy with Subcutaneous Parathyroid Forearm Autotransplantation in the Treatment of Secondary Hyperparathyroidism: A Single-Center Experience

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