. A text-book upon the pathogenic Bacteria and Protozoa for students of medicine and physicians. Bacteriology; Pathogenic bacteria; Protozoa. Cultivation 591 preparations the bacilli are always found in scattered groups, which are easily discovered, under a low power of the microscope, as reddish specks, and readily resolved into bacilli with the oil-im- mersion lens. In bacilli stained with the alkaline methylene-blue solution, dark-colored dots (Babes-Ernst or metachromatic granules) may sometimes be observed near the ends of the rods. Isolation.—The bacillus can be secured in pure culture f
. A text-book upon the pathogenic Bacteria and Protozoa for students of medicine and physicians. Bacteriology; Pathogenic bacteria; Protozoa. Cultivation 591 preparations the bacilli are always found in scattered groups, which are easily discovered, under a low power of the microscope, as reddish specks, and readily resolved into bacilli with the oil-im- mersion lens. In bacilli stained with the alkaline methylene-blue solution, dark-colored dots (Babes-Ernst or metachromatic granules) may sometimes be observed near the ends of the rods. Isolation.—The bacillus can be secured in pure culture from an enlarged lymphatic gland or from the splenic pulp of a case of typhoid. As the groups of bacilli are sometimes widely scattered through- out the spleen, E. Frankel recommends that as soon as the organ is removed from the body it be wrapped in cloths wet with a solution of bichlorid of mercury and kept for three days in a warm room, in order that a considerable and massive development of the bacilli. Fig. 249.—Bacillus typhi abdominalis; superficial colony two days old, as seen upon the surface of a gelatin plate. X 20 (Heim). may take place. The surface is then seared with a hot iron and ma- terial for cultures obtained by introducing a platinum loop into the substance of the organ through the sterilized surface. Cultures may be more easily obtained from the blood of the living patients. (See "Blood culture," under the section "Bacterio- logic ;) The bacilli can also be secured from the alvine discharges of typhoid patients during the second and third weeks of the disease. Cultivation.—The bacillus grows well upon all culture-media under both aerobic and anaerobic conditions. Colonies.—The deep colonies upon gelatin plates appear under the microscope of a brownish-yellow color and spindle-shape, and are sharply circumscribed. When superficial, however, they become larger and form a thin, bluish, iridescent layer with notched edges. T
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbacteri, bookyear1916
