Elements of human physiology / by Henry Power.

  • Henry Power
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: Elements of human physiology / by Henry Power. Source: Wellcome Collection.

    53/536 page 31
    The nature of fibrinogen lias been very carefully investigated by Hammarsten, who obtains the sub- stance to which he applies this name by opening a vein in the horse and receiving three or four volumes of blood in a vessel containing one volume of a satu- rated solution of magnesium sulphate, stirring the mixture vigorously and filtering. The corpuscles are thus separated from the fluid consisting of plasma and saline solution. Saturated solution of common salb is now added, and the precipitate collected in a filter; this is now extracted with an 8 per cent, solution of common salt, then precipitated with a saturated solu- tion of common salt, and this process is repeated three or four times successively. The last precipitate is dissolved in pure water, and the solution contains pure, typical, unchanged fibrinogen. On the addition of a little ferment the solution coagulates throughout. Fibrinogen is contained in hydrocele fluid, from which it can be precipitated by saturation with hydrocele. Fi]l>riii ferment.—This may be obtained by adding absolute alcohol to blood serum till the whole of the proteids are precipitated. The precipitate is collected and kept in absolute alcohol for at least a fortnight. The proteids are by this means rendered nearly insoluble in water, whilst the ferment, being unaffected by alcohol, can be extracted by means of water, mingled only with a very small quantity of albumin, from which it can be freed by the trans- mission of CO2, or by the cautious addition of acetic acid. Blood which is made to flow directly from the vein into absolute alcohol contains no fibrin ferment; it is therefore generated after the withdrawal of blood from the body, and antecedently to the occurrence of coagulation. The serum of blood.—The serum is the fluid that is gradually expressed from the clot by the con- traction of the fibrin, and which accumulates upon
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