. A text-book upon the pathogenic Bacteria and Protozoa for students of medicine and physicians. Bacteriology; Pathogenic bacteria; Protozoa. Fig. -Plasmodium falciparum. Ookinetes in the stomach of Anopheles (Grassi). mammals, the insect hosts, so far as known, are always mosquitoes. The mosquitoes become infected by biting and sucking the blood of infected animals; the warm-blooded animals become infected by being bitten by infected mosquitoes, and so on, in endless cycles. The parasites differ but little in the details of structure and de- velopment, so that the following description
. A text-book upon the pathogenic Bacteria and Protozoa for students of medicine and physicians. Bacteriology; Pathogenic bacteria; Protozoa. Fig. -Plasmodium falciparum. Ookinetes in the stomach of Anopheles (Grassi). mammals, the insect hosts, so far as known, are always mosquitoes. The mosquitoes become infected by biting and sucking the blood of infected animals; the warm-blooded animals become infected by being bitten by infected mosquitoes, and so on, in endless cycles. The parasites differ but little in the details of structure and de- velopment, so that the following description may serve as a type for all: From the proboscis of the mosquito, with its saliva, from cells in the salivary glands where they have been harbored, tiny elongate spindles, measuring about n in length and ^ in breadth, and known as sporozoits, enter the blood of the individual bitten. These sporozoits attach themselves to the red blood-cor- puscles, gradually lose their elongate form, and become irregularly spherical. There is some difference of opinion as whether the little bodies are simply upon the corpuscles, as Koch believed, or in the corpuscles, as the majority of writers believe, but it is an immate- rial difference, for the parasite soon makes clear that it is consuming the corpuscle. This little body is known as a sckizont. When stained with polychrome meth- ylene-blue, and examined under a high power of the microscope, it appears as a httle ring with a dark chromatin dot upon one side. It grows steadily, feeding upon the hemoglobin, which seems to be chemically transformed into fine or coarse granules of a bacillary or rounded form, presumably melanin. In a length of time that. Fig. 179.—Plasmodium fal- ciparum. Transverse section of the stomach of Anopheles, showing the ookinetes of the parasite in various stages of development attached to the outer surface (Grassi).. Please note that these images are extracted from scanned page images that may have been dig
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbacteri, bookyear1916
