ABSTRACT
The natural history of 383 patients of schistosomal cirrhosis, discovered from 1960-1990 in Donjing township Shanghai suburb, where schistosomiasis had been controlled for more than 10 years, was studied. The cumulative survival rate in 243 patients who had splenecto-my 11-30 years previously (group I ) was much higher than that of 140 patients without splenectomy (group II ), and the time for 75% survival rate of these 2 groups were 18 and 4 years respectively, being much longer in the splenectomized patients without ascites and those operated before age of 30 than those complicated with ascites and those operated between the age of 31 - 50 or after 51 years of age.The complications and mortality rate of group I were significantly lower than that of group I , indicating that splenectomy not only prevented the complication of portal hypertension but improved the general health and resistance of the patients against other pathogens as well.There was no significant difference between group I and group II in the ratio of the avarage death age of the deceased patients to the life expectancy of the general population, suggesting that the life span of a number of patients without splenectomy are not substantially shortened in an area where schistosomiasis had been controlled.
ABSTRACT
Mice of Kunming strain were infected with Schistosoma japonicum cercariae previously incubated with various concentrations of acridine mutagen ICR-170 for different time durations. At 6 weeks after infection, the mice were autopsied. The results showed that 24 out of 28(85. 7%) adult female worms had deformed or lacked ovaries and vitelline glands when the cercariae were treated with the agent at a concentration of 10?g/ml and incubated at 30. 5℃ for 30min. No apparnet changes were observed in the male worms inhabiting the mesenteric and portal veins with the females worms in their gynecophoral canals. The mutagenized female schistosomes obtained from the present experiment might be served as another form of attenuated worms for the induction of protective immunity.