The tolerance to ammonia and nitrites in freshwater ciliate Paramecium bursaria was measured in a conventional open system. The ciliate was exposed to different concentrations of ammonia and nitrites for 2h and 12h in...The tolerance to ammonia and nitrites in freshwater ciliate Paramecium bursaria was measured in a conventional open system. The ciliate was exposed to different concentrations of ammonia and nitrites for 2h and 12h in order to determine the lethal concentrations. Linear regression analysis revealed that the 2h-LC50 value for ammonia was 95.94 mg/L and for nitrite 27.35 mg/L using probit scale method (with 95% confidence intervals). There was a linear correlation between the mortality probit scale and logarithmic concentration of ammonia which fit by a regression equation y=7.32x–9.51 (R2=0.98; y, mortality probit scale; x, logarithmic concentration of ammonia), by which 2 h–LC50 value for ammonia was found to be 95.50 mg/L. A linear correla- tion between mortality probit scales and logarithmic concentration of nitrite is also followed the regression equa- tion y=2.86x+0.89 (R2=0.95; y, mortality probit scale; x, logarithmic concentration of nitrite). The regression analysis of toxicity curves showed that the linear correlation between exposed time of ammonia-N LC50 value and ammonia-N LC50 value followed the regression equation y=2 862.85e-0.08x (R2=0.95; y, duration of exposure to LC50 value; x, LC50 value), and that between exposed time of nitrite-N LC50 value and nitrite-N LC50 value followed the regression equation y = 127.15e-0.13x (R2=0.91; y, exposed time of LC50 value; x, LC50 value). The results demonstrate that the tolerance to ammonia in P. bursaria is considerably higher than that of the larvae or juveniles of some metozoa, e.g. cultured prawns and oysters. In addition, ciliates, as bacterial predators, are likely to play a positive role in maintaining and improving water quality in aquatic environments with high-level ammonium, such as sewage treatment systems.展开更多
AIM:To investigate the efficacy and tolerability of albendazole and metranidazole treatment in giardiasis. METHODS:The open comparative randomized trial was carried out prospectively from December 1999 to July 2001 in...AIM:To investigate the efficacy and tolerability of albendazole and metranidazole treatment in giardiasis. METHODS:The open comparative randomized trial was carried out prospectively from December 1999 to July 2001 in Duzce City of Turkey.The diagnosis was based on the presence of signs and symptoms compatible with giardiasis including a positive stool examination of giardia cysts or trophozoite.Metranidazole group consisted of 29 patients and was given metranidazole 500 mg,three times a day for 5 d and albendazole group was consisted of 28 patients and was given albendazole 400 mg/d for 5 d. RESULTS:There were no significant differences in demographical and therapeutical effects and patient's compliance between both groups.But side effects were seen more in metranidazole group than in albendazole group. CONCLUSION:Albendazole is as effective as metranidazole in adults' giardiasis.Albendazole has less side effect potentials than metranidazole in the treatment of giardiasis.展开更多
文摘The tolerance to ammonia and nitrites in freshwater ciliate Paramecium bursaria was measured in a conventional open system. The ciliate was exposed to different concentrations of ammonia and nitrites for 2h and 12h in order to determine the lethal concentrations. Linear regression analysis revealed that the 2h-LC50 value for ammonia was 95.94 mg/L and for nitrite 27.35 mg/L using probit scale method (with 95% confidence intervals). There was a linear correlation between the mortality probit scale and logarithmic concentration of ammonia which fit by a regression equation y=7.32x–9.51 (R2=0.98; y, mortality probit scale; x, logarithmic concentration of ammonia), by which 2 h–LC50 value for ammonia was found to be 95.50 mg/L. A linear correla- tion between mortality probit scales and logarithmic concentration of nitrite is also followed the regression equa- tion y=2.86x+0.89 (R2=0.95; y, mortality probit scale; x, logarithmic concentration of nitrite). The regression analysis of toxicity curves showed that the linear correlation between exposed time of ammonia-N LC50 value and ammonia-N LC50 value followed the regression equation y=2 862.85e-0.08x (R2=0.95; y, duration of exposure to LC50 value; x, LC50 value), and that between exposed time of nitrite-N LC50 value and nitrite-N LC50 value followed the regression equation y = 127.15e-0.13x (R2=0.91; y, exposed time of LC50 value; x, LC50 value). The results demonstrate that the tolerance to ammonia in P. bursaria is considerably higher than that of the larvae or juveniles of some metozoa, e.g. cultured prawns and oysters. In addition, ciliates, as bacterial predators, are likely to play a positive role in maintaining and improving water quality in aquatic environments with high-level ammonium, such as sewage treatment systems.
文摘AIM:To investigate the efficacy and tolerability of albendazole and metranidazole treatment in giardiasis. METHODS:The open comparative randomized trial was carried out prospectively from December 1999 to July 2001 in Duzce City of Turkey.The diagnosis was based on the presence of signs and symptoms compatible with giardiasis including a positive stool examination of giardia cysts or trophozoite.Metranidazole group consisted of 29 patients and was given metranidazole 500 mg,three times a day for 5 d and albendazole group was consisted of 28 patients and was given albendazole 400 mg/d for 5 d. RESULTS:There were no significant differences in demographical and therapeutical effects and patient's compliance between both groups.But side effects were seen more in metranidazole group than in albendazole group. CONCLUSION:Albendazole is as effective as metranidazole in adults' giardiasis.Albendazole has less side effect potentials than metranidazole in the treatment of giardiasis.
