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正

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The therapeutic effectiveness of intramuscularly administeredsodium cobaltinitrite [Na

3

Co（NO

2

）

6

] in antagonizing cyanide poisoning indogs and cats was studied. A solution of Na

3

Co（NO

2

）

6

in 10% dimethylsulfoxide （DMSO） was intramuscularly injected to cyanide-poisoned dogswhen convulsion developed about 5-10 minutes after intramuscularadministration of 1-2.5 LD of potassium cyanide（KCN） or 15 seconds afterinhalation of 2LD

50

’s of hydrocyanic acid（HCN）. It was found that afterbeing treated with Na

3

Co（NO

2

）

6

20 out of the 22 KCN-poisoned dogs and 8but of the 10 HCN-poisoned dogs survived. A satisfactory therapeutic effectwas also observed in cats intoxicated with lethal doses of HCN. Ourstudies provide an experimental basis for the search for an effective cyanideantidote which possesses a fast antidotal effect and a convenient route ofadministration and is thus suitable for on-the-spot rescue in a chemicalcombat.