A feeling of a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a sense of weariness and fatigue.
Tiredness is not a singular symptom that defines any one particular disease. Rather, tiredness can be a symptom of many different diseases and conditions. The causes of tiredness range from lack of sleep or excessive exercise to significant medical and surgical problems.
The lack of energy associated with tiredness can sometimes cause difficulty with normal daily activities, leading to problems with attentiveness and concentration.
A group or layer of cells that perform specific functions. For example, muscle tissue is a group of muscle cells.
- Tissue plasminogen activator
(tPA) An enzyme that helps dissolve clots. tPA is made by the cells lining blood vessels and has also been made in the laboratory. It is systemic thrombolytic (clot-busting) agent and is used in the treatment of heart attack and stroke. Activase (alteplase) is a tissue plasminogen activator produced by recombinant DNA technology. Recombinant tPA […]
- Tissue, lymphoid
A part of the body’s immune system that helps protect it from bacteria and other foreign entities. Lymphoid tissue is rich in lymphocytes (and accessory cells such as macrophages and reticular cells). The lymphoid tissue includes the lymph nodes, spleen, tonsils, adenoids and the thymus (an organ in the chest that is particularly large during […]
The concentration of a substance in a fluid, such as the concentration of an antibody in blood. The titer reflects the amount of the substance in the fluid. Sometimes also spelled titre.
A giant filamentous protein essential to the structure, development, and elasticity of muscle. The gene encoding titin is mutated in tibial muscular dystrophy.