edgepedia

Human health and medicine

25,729 articles

Reebok Pump

Reebok Pump, or The Pump (Performance Under Maximum Pressure), is Reebok's 1989 inflatable-fit basketball shoe invented by Paul Litchfield, priced at $170, made famous by Dee Brown's 1991 dunk contest.

Reed V. Tuckson

Reed V. Tuckson is an American physician and public health leader who served as D.C. health commissioner, president of Charles R. Drew University, and a UnitedHealth Group executive.

Reed–Sternberg cell

Reed–Sternberg cell (Sternberg–Reed cell): giant multinucleated malignant B cell, 15–45 µm, CD30+/CD15+, defining classic Hodgkin lymphoma; described by Sternberg (1898) and Reed (1902), usually under 10% of tumor cellularity.

Reelin

Reelin (RELN gene) is a large extracellular matrix glycoprotein controlling neuronal migration and cortical layering via ApoER2/VLDLR-Dab1 signaling; absent in reeler mice, lost in human lissencephaly, and protective COLBOS variants delay Alzheimer's disease.

Refeeding syndrome

Refeeding syndrome, also called realimentation syndrome, is a potentially life-threatening fall in serum phosphorus, potassium, and magnesium within hours to days after feeding resumes in a substantially undernourished person.

Reference Daily Intake

The Reference Daily Intake (RDI) is a set of reference values from the US FDA for vitamins, minerals, and protein, used to calculate the % Daily Value on nutrition labels.

Reference ranges for blood tests

Reference ranges for blood tests (reference intervals) are the central 95% of values from healthy populations, defined by CLSI/IFCC EP28-A3c; they vary by laboratory, method, age, and sex, and harmonization efforts seek common intervals.

Referential thinking

Referential thinking, also called ideas of reference, is the tendency to interpret neutral events or others' actions as carrying unusual meaning directed at oneself; it is a common psychotic symptom.

Referred pain

Referred pain, also called pain referral, is pain felt at a site distant from its source, such as cardiac pain in the left arm or gallbladder pain in the right scapula, explained mainly by convergence projection.

Reflex

A reflex is an automatic, involuntary response to a stimulus mediated by a fixed neural pathway, the reflex arc, ranging from the knee jerk to protective withdrawal.

Reflex arc

A reflex arc, or reflex circuit, is the neural pathway that produces an automatic, involuntary response to a stimulus, integrating it in the spinal cord or brainstem without conscious involvement.

Reflex incontinence

Reflex incontinence (ICD-11 MF50.24): urinary incontinence accompanying detrusor hyperreflexia, leaking without warning urge after nerve damage from stroke, spinal cord injury, or multiple sclerosis; managed with catheterization and anticholinergics.

Reflex syncope

Reflex syncope, or neurally mediated syncope, is fainting from an inappropriate cardiovascular reflex causing vasodilatation and/or bradycardia; forms include vasovagal, situational, and carotid sinus syncope, treated first with counterpressure maneuvers and, in selected asystolic cases, pacing.

Reflex testing (laboratory medicine)

Reflex testing is a laboratory medicine practice in which a pre-determined result, such as a positive screen, automatically triggers confirmatory tests on the same specimen without a new physician order.

Reflexology

Reflexology, also called zone therapy, is a complementary therapy applying pressure to foot or hand points believed to map to body organs; clinical evidence for claimed healing effects is weak and unproven.

Reflexotherapy

Reflexotherapy, a term also used for reflexology, is the treatment of a condition by producing a reflex action, such as stopping a nosebleed with ice applied to the cervical spine.

Reflux finding score

The reflux finding score is an endoscopic scoring system grading eight laryngeal findings to estimate laryngopharyngeal reflux, introduced in 2001, with a score above 7 indicating treatment.

Refractive error

A refractive error is a common eye condition where the eye's shape or length keeps light from focusing on the retina, causing blurred vision that eyeglasses correct.

Refractive surgery

Refractive surgery, also called keratorefractive or corneal refractive surgery when corneal, is elective eye surgery reducing dependence on glasses or contacts. Includes LASIK, PRK, LASEK, SMILE, phakic IOLs, and refractive lens exchange; corrects myopia, hyperopia, and astigmatism but not presbyopia.

Refractory anemia

Refractory anemia is anemia unresponsive to hematinics such as iron, vitamin B12, or folate, a term coined in 1938 and now classified as myelodysplastic syndrome with low blasts.

Refractory anemia with excess blasts in transformation

Refractory anemia with excess blasts in transformation (RAEB-T), a historical FAB 1982 MDS subtype with 20-29% marrow blasts, >5% blood blasts, or Auer rods; eliminated by WHO 2001, now AML or MDS-IB2/MDS/AML.

Refractory anemia with ring sideroblasts

Refractory anemia with ring sideroblasts (RARS), now MDS-RS-SLD or MDS-SF3B1, is an acquired clonal sideroblastic anemia within MDS. SF3B1 mutations in ~80% of cases; median age 71; low AML risk; treated with ESAs, luspatercept, and iron chelation.

Refractory angina

Refractory angina is chronic angina lasting at least 3 months that cannot be controlled by medication, angioplasty, or coronary bypass surgery, affecting about 5–10% of patients with stable coronary artery disease.

Refractory celiac disease

Refractory celiac disease (RCD), types I and II, persistent malabsorption and villous atrophy despite a strict gluten-free diet; type II has aberrant clonal IELs, high EATL risk, 44% 5-year survival.

Refractory cytopenia of childhood

Refractory cytopenia of childhood (RCC), ICD-11 2A38, the most common childhood myelodysplastic neoplasm: persistent cytopenia, under 5% marrow and 2% blood blasts, often hypocellular marrow, monosomy 7 in 8–48%.

Refractory hypertension

Refractory hypertension, or refractory hypertensive state, is blood pressure that remains uncontrolled despite five or more antihypertensive medications at maximal doses, a severe subgroup of resistant hypertension.

Refractory period (physiology)

Refractory period (physiology): post-action-potential interval in neurons and muscle, with absolute phase (Na+ channel inactivation, no second spike) and relative phase (elevated K+ conductance, stronger stimulus needed); limits firing rate and ensures unidirectional conduction.

Refractory thrombocytopenia

Refractory thrombocytopenia (RT), ICD-11 2A32, a rare myelodysplastic syndrome subtype with isolated low platelets and ≥10% dysplastic megakaryocytes; formerly WHO 2008 RCUD, now MDS-SLD, distinguished from ITP.

Reframe-IT+U trial

Reframe-IT+U trial (NCT07001202): a quasi-experimental pilot of a six-session blended CBT intervention for suicidal ideation in Chilean university students, adapted from Reframe-IT+ (schools) and Reframe-IT (Australia), assessing acceptability and feasibility.

Refrigerator death

Refrigerator death, also called fridge death, is suffocation of a person, usually a child, trapped in a refrigerator with a door that cannot be opened from inside.