Category: O

A substance that combines with oxygen and is oxidized when a substrate is reduced by an enzyme.  

A chronic disease of the nose of an inflammatory nature, combined with atrophy of the mucous membrane and the formation of extremely foul-smelling crusts in the interior of the nose.  

A platinum-based anticancer drug given intravenously for the treatment of colorectal cancer with metastases. It is usually combined with fluorouracil and folinic acid. Side-effects include toxic damage to the nervous system.  

Also called aerotitis, this is blockage of the eustachian tubes between the middle ear and the pharynx as a result of rapidly changing external air pressure, such as occurs during descent of an aircraft. valsalvas manoeuvre pinching the nose with finger and thumb and attempting to blow hard through the nose will usually relieve the…

A small accessory bone behind the ankle joint which is present in about 7 per cent of the population. It may be damaged by energetic springing from the toes in ballet, jumping or fast bowling.    

Replacement of bone by a highly cellular and vascular connective tissue. It is due to excessive parathyroid activity, and is seen in some patients with primary hyperparathyroidism and those with uraemic osteodystrophy the secondary hyperparathyroidism that occurs in patients with chronic renal disease.  

Organophosphorus insecticides act by inhibiting the action of cholinesterase. For this reason they are also toxic to humans and must therefore be handled with great care. The most widely used are parathion and malathion. Organophosphorus has also been used to make nerve gases.  

Organic Substances are those obtained from animal or vegetable bodies, or which resemble in chemical composition those derived from this source. Organic chemistry has come to mean the chemistry of the carbon compounds.  

A description usually applied to infection resulting from an organism that does not normally cause disease in a healthy individual. The body’s defense mechanism can usually combat these organisms, but if it is impaired as happens in AIDS/HIV or other immune deficiencies opportunistic infection may develop. Some viral and fungal infections behave in this way.…

The most common effects of opioid overdose are vomiting, drowsiness, pinpoint pupils, bradycardia, convulsions and coma. Respiratory depression is common and may lead to cyanosisS and respiratory arrest. Hypotension occurs occasionally, and in severe cases non-cardiogenic pulmonary oedema and cardiovascular collapse may occur. Cardiac arrhythmia may occur with some opioids. Some opioids have a histamine-releasing…