The activation of poliomyelitis virus from a "neutral" virus-antibody mixture by the addition of non-infectious virus is described. The phenomenon was demonstrated in tissue cultures using both Petri dishes and roller tubes. The reaction was found to be type-specific and a relationship between antigen dilution and number of plaques counted was established. The relative potency of vaccine prepar...

Overseas investigations have shown that many healthcare institutions are understocked of antidotes to treat these patients. 1–4 Despite a recent study to the contrary, 5 the paper by Fountain and colleagues, published in this issue of the New Zealand Medical Journal, suggests similar problems in New Zealand hospitals with shortcomings in hospital pharmacy stocks and resupply. 6 The paper raises...

In reality, humans are always exposed to a combination of toxic substances and seldom to a single agent. Simultaneous exposure to a multitude of chemicals could result in unexpected consequences. The combined risk may lead to greater or less than a simple summation of the effects induced by chemicals given individually. Here, a method is proposed for estimating the cumulative risk which is the ...

BACKGROUND Urogenital symptoms are common among postmenopausal women. Such symptoms may be alleviated by low-potency oestrogen formulations administered orally or vaginally. Although low-potency oestrogen formulations are assumed to have few, if any, adverse effects on the endometrium, risk of endometrial neoplasia has not been quantified. METHODS In a nationwide population-based case-control...

stability studies play a critical role in assuring product quality at all points in the vaccine life cycle. these studies used to determine vaccine expiry date and vaccine efficacy. accelerated stability and long term stability study performed for three batches of trivalent oral poliomyelitis vaccine (opv) and three batches of monovalent opv (type1) manufactured by razi institute. after samplin...