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Parathyroid Gland
Parathyroid glands are small endocrine glands in the neck of humans and other tetrapods. Humans usually have four parathyroid glands, located on the back of the thyroid gland in variable locations. The parathyroid gland produces and secretes parathyroid hormone in response to a low blood calcium, which plays a key role in regulating the amount of calcium in the blood and within the bones. Parathyroid glands share a similar blood supply, venous drainage, and lymphatic drainage to the thyroid glands. Parathyroid glands are derived from the epithelial lining of the third and fourth pharyngeal pouches, with the superior glands arising from the fourth pouch and the inferior glands arising from the higher third pouch. The relative position of the inferior and superior glands, which are named according to their final location, changes because of the migration of embryological tissues. Hyperparathyroidism and hypoparathyroidism, characterized by alterations in the blood calcium levels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Neck
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, and language. Humans are highly social and tend to live in complex social structures composed of many cooperating and competing groups, from families and kinship networks to political states. Social interactions between humans have established a wide variety of values, social norms, and rituals, which bolster human society. Its intelligence and its desire to understand and influence the environment and to explain and manipulate phenomena have motivated humanity's development of science, philosophy, mythology, religion, and other fields of study. Although some scientists equate the term ''humans'' with all members of the genus ''Homo'', in common usage, it generally refers to ''Homo sapiens'', the only extant member. Anatomically mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocrine Gland
Endocrine glands are ductless glands of the endocrine system that secrete their products, hormones, directly into the blood. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands. The hypothalamus and pituitary glands are neuroendocrine organs. Pituitary gland The pituitary gland hangs from the base of the brain by the pituitary stalk, and is enclosed by bone. It consists of a hormone-producing glandular portion of the anterior pituitary and a neural portion of the posterior pituitary, which is an extension of the hypothalamus. The hypothalamus regulates the hormonal output of the anterior pituitary and creates two hormones that it exports to the posterior pituitary for storage and later release. Four of the six anterior pituitary hormones are tropic hormones that regulate the function of other endocrine organs. Most anterior pituitary horm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Cervical Lymph Node
The deep cervical lymph nodes are a group of cervical lymph nodes found near the internal jugular vein in the neck. Structure The deep cervical lymph nodes can be divided into upper and lower groups, or superior and inferior groups. Alternatively, they can be divided into deep anterior cervical lymph nodes and deep lateral cervical lymph nodes. They can also be divided into three groups: "superior deep jugular", "middle deep jugular", and "inferior deep jugular". Location The deep cervical lymph nodes are contained in the carotid sheath in the neck, close to the internal jugular vein. They connect to the meningeal lymphatic vessels superiorly. Function The deep cervical lymph nodes provide lymphatic drainage to many parts of the head, including the pharynx, mouth, and meninges In anatomy, the meninges (, ''singular:'' meninx ( or ), ) are the three membranes that envelop the brain and spinal cord. In mammals, the meninges are the dura mater, the arachnoid mater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachiocephalic Vein
The left and right brachiocephalic veins (previously called innominate veins) are major veins in the upper chest, formed by the union of each corresponding internal jugular vein and subclavian vein. This is at the level of the sternoclavicular joint. The left brachiocephalic vein is nearly always longer than the right. These veins merge to form the superior vena cava, a great vessel, posterior to the junction of the first costal cartilage with the manubrium of the sternum. The brachiocephalic veins are the major veins returning blood to the superior vena cava. Tributaries The brachiocephalic vein is formed by the confluence of the subclavian and internal jugular veins. In addition it receives drainage from: * Left and right internal thoracic vein (Also called internal mammary veins): drain into the inferior border of their corresponding vein * Left and right inferior thyroid veins: drain into the superior aspect of their corresponding veins near the confluence * Left and rig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Jugular Vein
The internal jugular vein is a paired jugular vein that collects blood from the brain and the superficial parts of the face and neck. This vein runs in the carotid sheath with the common carotid artery and vagus nerve. It begins in the posterior compartment of the jugular foramen, at the base of the skull. It is somewhat dilated at its origin, which is called the ''superior bulb''. This vein also has a common trunk into which drains the anterior branch of the retromandibular vein, the facial vein, and the lingual vein. It runs down the side of the neck in a vertical direction, being at one end lateral to the internal carotid artery, and then lateral to the common carotid artery, and at the root of the neck, it unites with the subclavian vein to form the brachiocephalic vein (innominate vein); a little above its termination is a second dilation, the ''inferior bulb''. Above, it lies upon the rectus capitis lateralis, behind the internal carotid artery and the nerves pas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Churchill Livingstone
Churchill Livingstone is an academic publisher. It was formed in 1971 from the merger of Longman's medical list, E & S Livingstone (Edinburgh, Scotland) and J & A Churchill (London, England) and was owned by Pearson PLC, Pearson. Harcourt (publisher), Harcourt acquired Churchill Livingstone in 1997. It is now integrated as an imprint (trade name), imprint in Elsevier's health science division after Elsevier acquired Harcourt in 2001. In the past it published a number of classic medical texts, including Sir William Osler's textbook ''The Principles and Practice of Medicine, Gray's Anatomy,'' and ''Margaret Myles, Myles' Textbook for Midwives.'' In the 1980s, in addition to new texts in all areas of clinical medicine, it published an extensive list of medical and nursing textbooks in low-cost editions for low-income countries supported by the UK-funded Educational Low Priced Book Scheme (ELBS). [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lentil
The lentil (''Lens culinaris'' or ''Lens esculenta'') is an edible legume. It is an annual plant known for its lens-shaped seeds. It is about tall, and the seeds grow in pods, usually with two seeds in each. As a food crop, the largest producer is Canada, producing 45% of the world’s total lentils. In cuisines of the Indian subcontinent, where lentils are a staple, split lentils (often with their hulls removed) known as dal are often cooked into a thick curry/gravy that is usually eaten with rice or '' rotis''. Botanical description Name Many different names in different parts of the world are used for the crop lentil. The first use of the word ''lens'' to designate a specific genus was in the 16th century by the botanist Tournefort. The word "lens" for the lentil is of classical Roman/Latin origin: McGee points out that a prominent Roman family took the name " Lentulus", just as the family name "Cicero" was derived from the chickpea, '' Cicer arietinum'', or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thyroid is located at the front of the neck, below the Adam's apple. Microscopically, the functional unit of the thyroid gland is the spherical thyroid follicle, lined with follicular cells (thyrocytes), and occasional parafollicular cells that surround a lumen containing colloid. The thyroid gland secretes three hormones: the two thyroid hormones triiodothyronine (T3) and thyroxine (T4)and a peptide hormone, calcitonin. The thyroid hormones influence the metabolic rate and protein synthesis, and in children, growth and development. Calcitonin plays a role in calcium homeostasis. Secretion of the two thyroid hormones is regulated by thyroid-stimulating hormone (TSH), which is secreted from the anterior pituitary gland. TSH is regula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Remodeling
Bone remodeling (or bone metabolism) is a lifelong process where mature bone tissue is removed from the skeleton (a process called ''bone resorption'') and new bone tissue is formed (a process called ''ossification'' or ''new bone formation''). These processes also control the reshaping or replacement of bone following injuries like fractures but also micro-damage, which occurs during normal activity. Remodeling responds also to functional demands of the mechanical loading. In the first year of life, almost 100% of the skeleton is replaced. In adults, remodeling proceeds at about 10% per year. An imbalance in the regulation of bone remodeling's two sub-processes, bone resorption and bone formation, results in many metabolic bone diseases, such as osteoporosis. Physiology Bone homeostasis involves multiple but coordinated cellular and molecular events. Two main types of cells are responsible for bone metabolism: osteoblasts (which secrete new bone), and osteoclasts (which bre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoparathyroidism
Hypoparathyroidism is decreased function of the parathyroid glands with underproduction of parathyroid hormone (PTH). This can lead to low levels of calcium in the blood, often causing cramping and twitching of muscles or tetany (involuntary muscle contraction), and several other symptoms. It is a very rare disease. The condition can be inherited, but it is also encountered after thyroid or parathyroid gland surgery, and it can be caused by immune system-related damage as well as a number of rarer causes. The diagnosis is made with blood tests, and other investigations such as genetic testing depending on the results. The primary treatment of hypoparathyroidism is calcium and vitamin D supplementation. Calcium replacement or vitamin D can ameliorate the symptoms but can increase the risk of kidney stones and chronic kidney disease. Additionally, injectable medications such as recombinant human parathyroid hormone or teriparatide may be given by injection to replace the missi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperparathyroidism
Hyperparathyroidism is an increase in parathyroid hormone (PTH) levels in the blood. This occurs from a disorder either within the parathyroid glands (primary hyperparathyroidism) or as response to external stimuli (secondary hyperparathyroidism). Symptoms of hyperparathyroidism are caused by inappropriately normal or elevated blood calcium leaving the bones and flowing into the blood stream in response to increased production of parathyroid hormone. In healthy people, when blood calcium levels are high, parathyroid hormone levels should be low. With long-standing hyperparathyroidism, the most common symptom is kidney stones. Other symptoms may include bone pain, weakness, depression, confusion, and increased urination. Both primary and secondary may result in osteoporosis (weakening of the bones). In 80% of cases, primary hyperparathyroidism is due to a single benign tumor known as a parathyroid adenoma. Most of the remainder are due to several of these adenomas. Very rarely it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharyngeal Pouch (embryology)
In the embryonic development of vertebrates, pharyngeal pouches form on the endodermal side between the pharyngeal arches. The pharyngeal grooves (or clefts) form the lateral ectodermal surface of the neck region to separate the arches. The pouches line up with the clefts, and these thin segments become gills in fish. Specific pouches First pouch The endoderm lines the future auditory tube (Pharyngotympanic Eustachian tube), middle ear, mastoid antrum, and inner layer of the tympanic membrane. Derivatives of this pouch are supplied by Mandibular nerve. Second pouch * Contributes the middle ear, palatine tonsils, supplied by the facial nerve. Third pouch * The third pouch possesses Dorsal and Ventral wings. Derivatives of the dorsal wings include the inferior parathyroid glands, while the ventral wings fuse to form the cytoreticular cells of the thymus. The main nerve supply to the derivatives of this pouch is Cranial Nerve IX, glossopharyngeal nerve. Fourth pouch Deriv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
