A manual of surgery : for students and practitioners / by William Rose and Albert Carless.

  • William Rose
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: A manual of surgery : for students and practitioners / by William Rose and Albert Carless. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

    32/1194 (page 32)
    it is important to note whether or not it will develop in contact with the air. This may be accomplished by the use of nutrient gelatine poured into test-tubes, some of which are allowed to cool in the vertical position, and others on the slant. The former are inoculated by puncturing the horizontal surface with an infected platinum wire (stab culture), the latter by streaking it along the oblique surface (streak culture), (Fig. 3). 3. Inoculation experiments are really the most reliable means of examining into the relations of micro-organisms to any particular affection; but it must be clearly recognised that animals are not neces- sarily affected in the same way as man. Koch has insisted on the four following essentials in order to prove the infective character of any particular disease; (i.) The organism must be present in every case, either in the tissues or in the blood. (ii.) It must be possible to cultivate it for many generations apart from the body. (hi.) Its inoculation into a suitable animal must be followed by the appearance of the specific disease; and (iv.) The organism must be found in the tissues or blood of the ani- mal infected in this manner. The question of Immunity from infective diseases has been, and still is, receiv- ing much attention from bacteriologists. Three different kinds of immunity [a] Natural immunity, by which is meant that certain individuals or animals are capable of resisting the action of microbes, which can develop m others, thus, rats are unharmed by anthrax bacilli, and the dog, the goat and the ass are practically immune to tubercle. This condition also obtains m the human subject; e.g., negroes are immune against yellow fever, whereas white people are extremely susceptible. , ■ -t ■ a (b) Acquired immunity may be active or passive. Active immunity is developed in the following ways: (i.) The individual is free from the danger of contract- ing a specific disease owing to his having already suffered ^0™ hfm^’as^a attack of any of the ordinary exanthemata or of syphilis protects him, as a rule? from further liability to that special affection. Occasionally, how- ever this immunity seems to wear itself out, and second attacks rnay then occun (ii.) Inoculation with repeated doses of the specific vprv <;mall oneS and gradually increasing, nn such a way and at such a time That the inSuafin readily throw it off. This has been chiefly employed amongst animals, (iii.) Inoculation with an attenuated or modi^d virus, which whilst not giving the patient *e disease, has yet such his constitution as to protect him from ih This has been ^^hsed by wifh good result in the prevention of anthrax in animals, the attenuation o Fig. 3.—Stab and Streak Cul- tures FOR Bacteria. (After Tillmanns.)