A substance, such as pollen, that causes an allergy. - Though allergens are not harmful themselves, when they are combined with certain antibodies, a reaction (i.e. the allergy) liberates substances that damage body cells and tissues.. A substance, such as pollen, that causes an allergy. [German. : , allergy; see allergy +. , -gen (from French. ; see-gen).]. alâ²lerÂ·genâ²ic (-jÄnâ²Ä­k) adj.
A Honor Society of Nursing (STTI) answered. Prognosis varies depending on the type of motor neuron disease (MND) and the age of onset. Some MNDs, such as Post-polio syndrome (PLS), are not fatal and progress slowly.People with Spinal muscular atrophy (SMA) may appear to be stable for long periods, but improvement should not be expected.ome MNDs, such as Post-polio syndrome (PLS), are not fatal and progress slowly. People with Spinal muscular atrophy (SMA) may appear to be stable for long periods, but improvement should not be expected.
Prognosis varies somewhat by cause and duration of the vegetative state. Prognosis may be better if the cause is a reversible metabolic condition (eg, toxic encephalopathy) than if the cause is neuronal death due to extensive hypoxia and ischemia or another condition.