Category: P

Hairlike processes present on the surface of certain bacteria. They are thought to be involved in adhesion of bacteria to other cells and in transfer of DNA during conjugation. Hairs; in bacteria, filamentous appendages of which there may be hundreds on a single cell. One function of pili is to attach the bacterium to cells…

Forward protrusion of the breastbone resulting in deformity of the chest. The condition is painless and harmless. A condition in which the sides of the chest are considerably flattened and the sternum is prominent. The sternal ends of the ribs are enlarged or beaded. Often there is a circular construction of the thorax at the…

A fungal disease of the hair in which the hair shafts carry hard masses of black or white fungus. The black fungus, Piedraia hortai, is found mainly in the tropics and the white variety, Trichosporon cutaneum, in temperate regions. Sheath-like nodular masses in the hair of the beard and mustache from growth of either Piedraia…

A yellow crystalline solid used as a dye and as a tissue fixative. A yellow, crystalline, solid substance which is used as a fixative for tissues being prepared for examination under a microscope; it is also used as a dye. A yellow crystalline substance that precipitates proteins and explodes when heated or charged. Salts of…

An eruption of large blisters occurring after exposure to light in people who have been in contact with certain plants, such as wild parsnip or cow parsley, to which they are sensitive.. A dermatitis produced by exposure to certain plants and then sunlight.  

A form of vitamin K occurring naturally in green plants but usually synthesized for use as an antidote to overdosage with anticoagulant drugs. It promotes the production of prothrombin, essential for the normal coagulation of blood.  

One of a group of solutions used to maintain tissues in a viable state. These solutions contain specific concentrations of substances that are vital for normal tissue function (e.g. sodium, potassium, calcium, chloride, magnesium, bicarbonate, and phosphate ions, glucose, and oxygen). An example of such a solution is ‘Ringer’s solution.  

A widely distributed genus of lice. The crab (or pubic) louse, P. pubis, is a common parasite of man that lives permanently attached to the body hair, particularly that of the pubic or perianal regions but also on the eyelashes and the hairs in the armpits. Crab lice are not known to transmit disease but…

Movement of a cell or organism in response to a stimulus of light. The reaction and movement of cells and microorganisms under the stimulus of light.  

Relating to or describing conditions of bright illumination. For example, photopic vision is vision in bright light, in which the cones of the retina are responsible for visual sensation.