Aids to surgery / by Joseph Cunning.

  • Cunning, Joseph.
Date:
1908
Catalogue details

Licence: In copyright

Credit: Aids to surgery / by Joseph Cunning. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    cultivation, and inoculation. Koch's laws as to estab- lishing a particular organism as the cause of a disease are : 1. The organism must be present in every case, either in the tissues or the blood. 2. It must be possible to cultivate it for many genera- tions apart from the body. 3. Its inoculation into a suitable animal must be followed by the appearance of the specific disease. 4. The organism must be found in the tissues or blood of the animal affected in this manner. Bacteria are found in earth, air, and water. The more crowded the population, the greater the number of organisms. In high mountains and at sea they are few in number. Certain food is required for them, the essentials of which are oxygen, hydrogen, carbon, nitrogen, and inorganic salts Organisms grow best at the body-tem- perature—984° F. Cold and desiccation arrest their growth, but do not kill. Any degree of heat above 57° C. kills bacteria if allowed to act long enough ; spores re- quire a higher temperature. Bacteria which can grow in and require oxygen are called aerobes. Those which require an oxygen-free atmosphere are called anaerobes. Bacterial Products.—The most important of these are toxins, intense poisons, which cause high tempera- ture if absorbed into the circulation. Other products are alkaloidal (ptomaines), ferments, acid and alkaline sub- stances, and gases. Pathogenic bacteria are those which can develop in living tissues ; non-pathogenic can only develop in dead structures, such as slough, serum, or pus, though the toxins formed may be absorbed. Sepsis. Sepsis is a general term which indicates that an operation wound or an accidental wound has become infected with bacteria. These may be either putrefactive or pyogenic organisms. The putrefactive organisms can only grow in dead tissues, but the toxins formed by them are so irritating as