Слово встречается в следующем контексте:The observation period was extended for the polar extract, because signs of irritation were still observed 72 hours post injection.
The mtracutaneous injection of the polar extract of the test item at doses of 0.2 mL caused slight to well-defined signs of irritation compared to the injection sites of the reagent control.
The injection of the non-polar extract of the test item at doses of 0.2 mL caused no signs of irritation compared to the injection sites of the reagent control.

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