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Lesion
A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classification or naming convention for lesions. Since lesions can occur anywhere in the body and the definition of a lesion is so broad, the varieties of lesions are virtually endless. Generally, lesions may be classified by their patterns, their sizes, their locations, or their causes. They can also be named after the person who discovered them. For example, Ghon lesions, which are found in the lungs of those with tuberculosis, are named after the lesion's discoverer, Anton Ghon. The characteristic skin lesions of a varicella zoster virus infection are called ''chickenpox''. Lesions of the teeth are usually called dental caries. Location Lesions are often classified by their tissue types or locations. For example, a "skin lesion" or a " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Caries
Tooth decay, also known as cavities or caries, is the breakdown of teeth due to acids produced by bacteria. The cavities may be a number of different colors from yellow to black. Symptoms may include pain and difficulty with eating. Complications may include inflammation of the tissue around the tooth, tooth loss and infection or abscess formation. The cause of cavities is acid from bacteria dissolving the hard tissues of the teeth ( enamel, dentin and cementum). The acid is produced by the bacteria when they break down food debris or sugar on the tooth surface. Simple sugars in food are these bacteria's primary energy source and thus a diet high in simple sugar is a risk factor. If mineral breakdown is greater than build up from sources such as saliva, caries results. Risk factors include conditions that result in less saliva such as: diabetes mellitus, Sjögren syndrome and some medications. Medications that decrease saliva production include antihistamines and anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bankart Lesion
A Bankart lesion is a type of shoulder injury that occurs following a dislocated shoulder. It is an injury of the anterior (inferior) glenoid labrum of the shoulder. When this happens, a pocket at the front of the glenoid forms that allows the humeral head to dislocate into it. It is an indication for surgery and often accompanied by a Hill-Sachs lesion, damage to the posterior humeral head. A bony Bankart is a Bankart lesion that includes a fracture of the anterior-inferior glenoid cavity of the scapula bone. The Bankart lesion is named after English orthopedic surgeon Arthur Sydney Blundell Bankart (1879–1951). Diagnosis The diagnosis is usually initially made by a combination of physical exam and medical imaging, where the latter may be projectional radiography (in cases of bony Bankart) and/or MRI of the shoulder. The presence of intra-articular contrast allows for better evaluation of the glenoid labrum. Type V SLAP tears extends into the Bankart defect. Treatment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Lesion
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying causes and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology ( chronic blistering conditions), cause (skin conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain Damage
Neurotrauma, brain damage or brain injury (BI) is the destruction or degeneration of brain cells. Brain injuries occur due to a wide range of internal and external factors. In general, brain damage refers to significant, undiscriminating trauma-induced damage. A common category with the greatest number of injuries is traumatic brain injury (TBI) following physical trauma or head injury from an outside source, and the term acquired brain injury (ABI) is used in appropriate circles to differentiate brain injuries occurring after birth from injury, from a genetic disorder (GBI), or from a congenital disorder (CBI). Primary and secondary brain injury, Primary and secondary brain injuries identify the processes involved, while focal and diffuse brain injury describe the severity and localization. Recent research has demonstrated that neuroplasticity, which allows the brain to reorganize itself by forming new neural connections throughout life, provides for rearrangement of its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, and plays important roles in the consolidation of information from short-term memory to long-term memory, and in spatial memory that enables navigation. The hippocampus is located in the allocortex, with neural projections into the neocortex in humans, as well as primates. The hippocampus, as the medial pallium, is a structure found in all vertebrates. In humans, it contains two main interlocking parts: the hippocampus proper (also called ''Ammon's horn''), and the dentate gyrus. In Alzheimer's disease (and other forms of dementia), the hippocampus is one of the first regions of the brain to suffer damage; short-term memory loss and disorientation are included among the early symptoms. Damage to the hippocampus can also result ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biopsy
A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a disease. The tissue is then fixed, dehydrated, embedded, sectioned, stained and mounted before it is generally examined under a microscope by a pathologist; it may also be analyzed chemically. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. An incisional biopsy or core biopsy samples a portion of the abnormal tissue without attempting to remove the entire lesion or tumor. When a sample of tissue or fluid is removed with a needle in such a way that cells are removed without preserving the histological architecture of the tissue cells, the procedure is called a needle aspiration biopsy. Biopsies are most commonly performed for insight into possible cancerous or inflammatory conditions. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coin Lesion
A lung nodule or pulmonary nodule is a relatively small focal density in the lung. A solitary pulmonary nodule (SPN) or coin lesion, is a mass in the lung smaller than three centimeters in diameter. A pulmonary micronodule has a diameter of less than three millimetres. There may also be multiple nodules. One or more lung nodules can be an incidental finding found in up to 0.2% of chest X-rays and around 1% of CT scans. The nodule most commonly represents a benign tumor such as a granuloma or hamartoma, but in around 20% of cases it represents a malignant cancer, especially in older adults and smokers. Conversely, 10 to 20% of patients with lung cancer are diagnosed in this way. If the patient has a history of smoking or the nodule is growing, the possibility of cancer may need to be excluded through further radiological studies and interventions, possibly including surgical resection. The prognosis depends on the underlying condition. Causes Not every round spot on a radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tumor
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists in growing abnormally, even if the original trigger is removed. This abnormal growth usually forms a mass, when it may be called a tumor. ICD-10 classifies neoplasms into four main groups: benign neoplasms, in situ neoplasms, malignant neoplasms, and neoplasms of uncertain or unknown behavior. Malignant neoplasms are also simply known as cancers and are the focus of oncology. Prior to the abnormal growth of tissue, as neoplasia, cells often undergo an abnormal pattern of growth, such as metaplasia or dysplasia. However, metaplasia or dysplasia does not always progress to neoplasia and can occur in other conditions as well. The word is from Ancient Greek 'new' and 'formation, creation'. Types A neoplasm can be benign, potenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ghon's Complex
Ghon's complex is a lesion seen in the lung that is caused by tuberculosis. The lesions consist of a Ghon focus along with pulmonary lymphadenopathy within a nearby pulmonary lymph node. A Ghons complex retains viable bacteria, making them sources of long-term infection, which may reactivate and trigger secondary tuberculosis later in life. In countries where cow milk infected with '' Mycobacterium bovis'' has been eliminated (due to culling of infected cows and pasteurization), primary tuberculosis is usually caused by '' Mycobacterium tuberculosis'' and almost always begins in the lungs. Typically, the inhaled bacilli implant in the distal airspaces of the lower part of the upper lobe or the upper part of the lower lobe, usually close to the pleura. As sensitization develops, a 1 to 1.5 cm area of gray-white inflammation with consolidation emerges, known as the Ghon focus. In most cases, the center of this focus undergoes caseous necrosis. Tubercle bacilli, either fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stroke
Stroke (also known as a cerebrovascular accident (CVA) or brain attack) is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functioning properly. Signs and symptoms of stroke may include an inability to move or feel on one side of the body, problems understanding or speaking, dizziness, or loss of vision to one side. Signs and symptoms often appear soon after the stroke has occurred. If symptoms last less than one or two hours, the stroke is a transient ischemic attack (TIA), also called a mini-stroke. Hemorrhagic stroke may also be associated with a severe headache. The symptoms of stroke can be permanent. Long-term complications may include pneumonia and loss of bladder control. The biggest risk factor for stroke is high blood pressure. Other risk factors include high blood cholesterol, to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chickenpox
Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus (VZV). The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab over. It usually starts on the chest, back, and face. It then spreads to the rest of the body. The rash and other symptoms, such as fever, tiredness, and headaches, usually last five to seven days. Complications may occasionally include pneumonia, inflammation of the brain, and bacterial skin infections. The disease is usually more severe in adults than in children. Chickenpox is an airborne disease which spreads easily from one person to the next through the coughs and sneezes of an infected person. The incubation period is 10–21 days, after which the characteristic rash appears. It may be spread from one to two days before the rash appears until all lesions have crusted over. It may also spread through contact with the blisters. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kainic Acid
Kainic acid, or kainate, is an acid that naturally occurs in some seaweed. Kainic acid is a potent neuroexcitatory amino acid agonist that acts by activating receptors for glutamate, the principal excitatory neurotransmitter in the central nervous system. Glutamate is produced by the cell's metabolic processes and there are four major classifications of glutamate receptors: NMDA receptors, AMPA receptors, kainate receptors, and the metabotropic glutamate receptors. Kainic acid is an agonist for kainate receptors, a type of ionotropic glutamate receptor. Kainate receptors likely control a sodium channel that produces excitatory postsynaptic potentials (EPSPs) when glutamate binds. Kainic acid is commonly injected into laboratory animal models to study the effects of experimental ablation. Kainic acid is a direct agonist of the glutamic kainate receptors and large doses of concentrated solutions produce immediate neuronal death by overstimulating neurons to death. Such d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
