Category: R

A tract of motor neurons that extends from the midbrain down to different levels in the spinal cord, carrying impulses that have traveled from the cerebral and cerebellar cortex via the nucleus ruber (red nucleus). The tract plays an important part in the control of skilled and dextrous movements. A descending tract of fibers arising…

A group of stains used for microscopical examination of blood cells, consisting of variable mixtures of thiazine dyes, such as azure B, with eosin. Romanovsky stains give characteristic staining patterns, on the basis of which blood cells are classified. The group includes the stains of Leishmann, Wright, May-Grunwald, Giemsa, etc.  

An early clinical sign of Chagas disease, appearing some three weeks after infection. There is considerable swelling of the eyelids of one or both eyes. This may be due to the presence of the parasites causing the disease but it may also be an allergic reaction to the repeated bites of their insect carriers.  

A drug, similar to isoprenaline, used as a bronchodilator to relieve asthma and chronic bronchitis. It is administered by inhalation; side-effects, following large doses, may include dizziness, fainting, tremor, anxiety, and fast heart rate.  

A virus disease of East Africa transmitted from animals to man by mosquitoes and causing symptoms resembling those of influenza. A virus disease, caused by a phlebovirus and transmitted by mosquitoes, at one time confined to sub-Saharan Africa and predominantly found in domestic animals such as cattle, sheep and goats. In the 1970s the disease…

An antibiotic used to treat certain infections, particularly tuberculosis. It is administered by  injection, inhalation, or in a solution applied to the infected area. Side-effects are uncommon.  

Either of two muscles (rhomboid major and rhomboid minor) situated in the upper part of the back, between the backbone and shoulder blade. They help to move the shoulder blade backward and upward.  

A genus of large bloodsucking bugs. R. prolixus is important in the transmission of Chagas disease in Central America and the northern part of South America.  

A genus of hard ticks widely distributed in the tropics. The dog tick (R. sanguineus) can suck the blood of man and is commonly involved in the transmission of diseases caused by rickettsiae. A surgical procedure in which selected nerve roots are cut at the point where they emerge from the spinal cord. In posterior…

The formation of nodules in the interior of the nose and nasopharynx, which become thickened. It is caused by bacterial infection with Klebsiella rhinoscleroma. A chronic, recurring granulomatous infection of the nasal passages and surrounding structures, sometimes leading to marked deformity of the nasal cavity, nasopharynx, paranasal sinuses, or eyes. The disease is caused by…