Control groups equivalence

The regiochemistry of the reaction of unsymmetrical allylic esters was addressed by the introduction of a silyl group, equivalent to H, on the carbon of the allylic terminus. Eor example, 25 bearing a BuMe2Si group afforded 26 as the sole product in the three-component coupling. Since the subsequent protodesilylation of 26 selectively formed 27 (Scheme 6.6), this sequential procedure provides a practical method to control the regiochemistry in the substitution of unsymmetrical allylic substrates [13 c]. 

Groups of 30 male and 30 female B6C3F] mice were administered 4 mmol/L ethylene dibromide (purity > 99%), a dose equivalent to 116 mg/kg bw for males and 103 mg/kg bw for females) in distilled drinking-water for 450 days. A control group of 60 males and 60 females was given distilled drinking-water. Ethylene dibromide induced squamous-cell carcinomas of the forestomach in 26/28 males and 27/29 females and squamous-cell papilloma of the oesophagus in 3/30 females compared with none in 45 male and 50 female controls (Van Duuren et al., 1985). 

While an analytical data base was developed, the data was not evaluated in comparison with other typical locations. In addition, the epidemiology did not use an appropriate control group. Rather than use an equivalent local population not subject to the same exposure, the comparison was with the national averages. It is well known that there are marked variations in rates in small groups within a large population. For this reason, the control and test population should have similar size as well as background except for the thesis being tested. 

High doses of 525 mg/kg/day of stevioside equivalent aqueous Stevia extract were administered to male and female mice during copulation and pregnancy periods [19]. The authors could not observe any difference in the copulation and conception averages and any change in the fetus and broods when compared with control groups. 

Critical care pharmacists have demonstrated numerous contributions to the cost-effective care of ICU patients. Pharmacist initiated interventions in a 1200-bed teaching hospital were demonstrated to lower the drug costs by 41% compared with a control group (mean 73.75 vs. 43.40 p< 0.001). " Approximately, fifty percent of the 259 patients were in critical care units. The majority (79%) of the interventions over the 30-day trial period were aimed at improving the quality of care, whereas the remaining 21% were to provide equivalent care at a lower cost. There was no impact on length of stay or readmission rates, but there was a trend toward lower hospital mortality in the intervention group. 

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