AtelectasisAtelectasis is the collapse or closure of a lung resulting in reduced or absent gas exchange. It is usually unilateral, affecting part or all of one lung. It is a condition where the alveoli are deflated down to little or no volume, as distinct from pulmonary consolidation, in which they are filled with liquid. It is often called a collapsed lung, although that term may also refer to pneumothorax. It is a very common finding in chest X-rays and other radiological studies, and may be caused by normal exhalation or by various medical conditions.
RadiosurgeryRadiosurgery is surgery using radiation, that is, the destruction of precisely selected areas of tissue using ionizing radiation rather than excision with a blade. Like other forms of radiation therapy (also called radiotherapy), it is usually used to treat cancer. Radiosurgery was originally defined by the Swedish neurosurgeon Lars Leksell as "a single high dose fraction of radiation, stereotactically directed to an intracranial region of interest".
PeriodontiumThe periodontium is the specialized tissues that both surround and support the teeth, maintaining them in the maxillary and mandibular bones. The word comes from the Greek terms περί peri-, meaning "around" and -odont, meaning "tooth". Literally taken, it means that which is "around the tooth". Periodontics is the dental specialty that relates specifically to the care and maintenance of these tissues. It provides the support necessary to maintain teeth in function.
First pass effectThe first pass effect (also known as first-pass metabolism or presystemic metabolism) is a phenomenon of drug metabolism at a specific location in the body which leads to a reduction in the concentration of the active drug, specifically when administered orally, before it reaches the site of action or systemic circulation. It is the fraction of drug lost during the process of absorption which is generally related to the liver and gut wall.
Stress fractureA stress fracture is a fatigue-induced bone fracture caused by repeated stress over time. Instead of resulting from a single severe impact, stress fractures are the result of accumulated injury from repeated submaximal loading, such as running or jumping. Because of this mechanism, stress fractures are common overuse injuries in athletes. Stress fractures can be described as small cracks in the bone, or hairline fractures. Stress fractures of the foot are sometimes called "march fractures" because of the injury's prevalence among heavily marching soldiers.
Child and adolescent psychiatryChild and adolescent psychiatry (or pediatric psychiatry) is a branch of psychiatry that focuses on the diagnosis, treatment, and prevention of mental disorders in children, adolescents, and their families. It investigates the biopsychosocial factors that influence the development and course of psychiatric disorders and treatment responses to various interventions. Child and adolescent psychiatrists primarily use psychotherapy and/or medication to treat mental disorders in the pediatric population.
Lichen sclerosusLichen sclerosus (LS) is a chronic, inflammatory skin disease of unknown cause which can affect any body part of any person but has a strong preference for the genitals (penis, vulva) and is also known as balanitis xerotica obliterans (BXO) when it affects the penis. Lichen sclerosus is not contagious. There is a well-documented increase of skin cancer risk in LS, potentially improvable with treatment. LS in adult age women is normally incurable, but improvable with treatment, and often gets progressively worse if not treated properly.
MicrovesicleMicrovesicles (ectosomes, or microparticles) are a type of extracellular vesicle (EV) that are released from the cell membrane. In multicellular organisms, microvesicles and other EVs are found both in tissues (in the interstitial space between cells) and in many types of body fluids. Delimited by a phospholipid bilayer, microvesicles can be as small as the smallest EVs (30 nm in diameter) or as large as 1000 nm. They are considered to be larger, on average, than intracellularly-generated EVs known as exosomes.
Minimally invasive procedureMinimally invasive procedures (also known as minimally invasive surgeries) encompass surgical techniques that limit the size of incisions needed, thereby reducing wound healing time, associated pain, and risk of infection. Surgery by definition is invasive and many operations requiring incisions of some size are referred to as open surgery. Incisions made during open surgery can sometimes leave large wounds that may be painful and take a long time to heal.
Left ventricular hypertrophyLeft ventricular hypertrophy (LVH) is thickening of the heart muscle of the left ventricle of the heart, that is, left-sided ventricular hypertrophy and resulting increased left ventricular mass. While ventricular hypertrophy occurs naturally as a reaction to aerobic exercise and strength training, it is most frequently referred to as a pathological reaction to cardiovascular disease, or high blood pressure. It is one aspect of ventricular remodeling. While LVH itself is not a disease, it is usually a marker for disease involving the heart.