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Corneal Wavefront Aberration
Asymmetries in the topography and refractive index of the corneal surface that affect visual acuity.
Year introduced: 2010
Tumor Escape
The ability of tumors to evade destruction by the IMMUNE SYSTEM. Theories concerning possible mechanisms by which this takes place involve both cellular immunity (IMMUNITY, CELLULAR) and humoral immunity (ANTIBODY FORMATION), and also costimulatory pathways related to CD28 ANTIGENS and B7-1 ANTIGEN.
Year introduced: 1996
Escape Reaction
Innate response elicited by sensory stimuli associated with a threatening situation, or actual confrontation with an enemy.
Year introduced: 1968
Chromosome Aberrations
Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.
Strabismus
Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh and Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)
Antigenic Drift and Shift
Changes in the ANTIGEN population by slow and minor (antigenic drift) or sudden and major mutations (antigenic shift). Accumulation of minor mutations in antigenic drift over time may require development of new vaccine (e.g., seasonal FLU VACCINES). Antigenic shift on the other hand is less common but may result in emergence of a new subtype or species and sometimes pandemics (e.g., H1N1 pandemics in 2009 and 2018 and COVID-19) due to lack of HERD IMMUNITY to the newly emerged novel pathogen.
Year introduced: 2022
Bias
Any deviation of results or inferences from the truth, or processes leading to such deviation. Bias can result from several sources: one-sided or systematic variations in measurement from the true value (systematic error); flaws in study design; deviation of inferences, interpretations, or analyses based on flawed data or data collection; etc. There is no sense of prejudice or subjectivity implied in the assessment of bias under these conditions.
Year introduced: 2018(1990)
Sex Chromosome Aberrations
Abnormal number or structure of the SEX CHROMOSOMES. Some sex chromosome aberrations are associated with SEX CHROMOSOME DISORDERS and SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT.
Epistasis, Genetic
A form of gene interaction whereby the expression of one gene interferes with or masks the expression of a different gene or genes. Genes whose expression interferes with or masks the effects of other genes are said to be epistatic to the effected genes. Genes whose expression is affected (blocked or masked) are hypostatic to the interfering genes.
Year introduced: 1979
Developmental Disabilities
Disorders in which there is a delay in development based on that expected for a given age level or stage of development. These impairments or disabilities originate before age 18, may be expected to continue indefinitely, and constitute a substantial impairment. Biological and nonbiological factors are involved in these disorders. (From American Psychiatric Glossary, 6th ed)
Ocular Motility Disorders
Disorders that feature impairment of eye movements as a primary manifestation of disease. These conditions may be divided into infranuclear, nuclear, and supranuclear disorders. Diseases of the eye muscles or oculomotor cranial nerves (III, IV, and VI) are considered infranuclear. Nuclear disorders are caused by disease of the oculomotor, trochlear, or abducens nuclei in the BRAIN STEM. Supranuclear disorders are produced by dysfunction of higher order sensory and motor systems that control eye movements, including neural networks in the CEREBRAL CORTEX; BASAL GANGLIA; CEREBELLUM; and BRAIN STEM. Ocular torticollis refers to a head tilt that is caused by an ocular misalignment. Opsoclonus refers to rapid, conjugate oscillations of the eyes in multiple directions, which may occur as a parainfectious or paraneoplastic condition (e.g., OPSOCLONUS-MYOCLONUS SYNDROME). (Adams et al., Principles of Neurology, 6th ed, p240)
Year introduced: 1990
Paraphilic Disorders
Disorders that include recurrent, intense sexually arousing fantasies, sexual urges, or behaviors generally involving nonhuman objects, suffering of oneself or partners, or children or other nonconsenting partners. (from DSM-V)
Year introduced: 2016(1981)
Scientific Experimental Error
Deviation or aberration in the practical implementation of standard empirical procedures, distinct from MEDICAL ERRORS and SCIENTIFIC MISCONDUCT.
Year introduced: 2018
Chromosome Duplication
An aberration in which an extra chromosome or a chromosomal segment is made.
Year introduced: 2011
Aberrometry
The use of an aberrometer to measure eye tissue imperfections or abnormalities based on the way light passes through the eye which affects the ability of the eye to focus properly.
Sverdlovsk Accidental Release
ANTHRAX outbreak that occurred in 1979 and was associated with a research facility in Sverdlovsk, in the Ural mountain region of central RUSSIA. Most victims worked or lived in a narrow zone extending from the facility. The zone of anthrax-caused livestock mortality paralleled the northerly wind that prevailed shortly before the outbreak. It was concluded that an escape of ANTHRAX caused outbreak.
Year introduced: 2009
Rhinometry, Acoustic
Diagnostic measurement of the nose and its cavity through acoustic reflections. Used to measure nasal anatomical landmarks, nasal septal deviation, and nasal airway changes in response to allergen provocation tests (NASAL PROVOCATION TESTS).
Year introduced: 2002
Hypoglossal Nerve Diseases
Diseases of the twelfth cranial (hypoglossal) nerve or nuclei. The nuclei and fascicles of the nerve are located in the medulla, and the nerve exits the skull via the hypoglossal foramen and innervates the muscles of the tongue. Lower brain stem diseases, including ischemia and MOTOR NEURON DISEASES may affect the nuclei or nerve fascicles. The nerve may also be injured by diseases of the posterior fossa or skull base. Clinical manifestations include unilateral weakness of tongue musculature and lingual dysarthria, with deviation of the tongue towards the side of weakness upon attempted protrusion.
Year introduced: 2000
Intracranial Hemorrhages
Bleeding within the SKULL, including hemorrhages in the brain and the three membranes of MENINGES. The escape of blood often leads to the formation of HEMATOMA in the cranial epidural, subdural, and subarachnoid spaces.
Chromosome Breakage
A type of chromosomal aberration involving DNA BREAKS. Chromosome breakage can result in CHROMOSOMAL TRANSLOCATION; CHROMOSOME INVERSION; or SEQUENCE DELETION.
Year introduced: 1997