[Systemic immunity of experimental animals immunized with cholera vaccines].

The levels of antitoxic and vibriocidal antibodies in the sera of suckling rabbits after their parenteral immunization with cholera vaccine, cholera toxoid and a combination of cholera vaccine and toxoid were examined. Cholera vaccine induces intensive production of vibriocidal antibodies, and cholera toxoid, of antitoxic antibodies. The parenteral administration of the serum of rabbits immunized with cholera toxoid neutralized the action of cholera toxin in the small intestine of suckling rabbits.

[Experimental research on cholera vaccines. Local immunity].

Parenteral immunization of rabbits with cholera vaccine decreased the number of Vibrio cholerae adhering to the mucous membrane of the small intestine. Cholera toxoid and the complex preparation ensure protection from the local action of cholera toxin on the ligated loop of the rabbit intestine, while cholera vaccine produces no effect under the same conditions. The use of three preparations under study leads to the decrease of exudative reaction to the introduction of live V.

[Measurement of the specific electrical resistance of the blood (rho) and its determination mathematically in dogs].

The role of specific electric resistance of blood (rho) in determining systolic cardiac volume by impedance plethysmography is discussed. It is pointed out that the known five mathematical equations for rho estimation by the hematocrit (Hct) and the temperature (T0) differ from one another and are moreover good for humans, but not for experimental animals. A suitable equipment and technique for direct (in vitro) measurement of rho is suggested.