PC:
Positive control; NC: Negative control TABLE 3.
The intensity of electric current was slowly increased by turning a dial on the tester from 0 to 10 at a rate of one numerical increase per five seconds until a response was obtained.3 The
positive control tooth was tested first, followed by the contralateral traumatized tooth.
The negative control group had uncontaminated burs (new/unused) while the
positive control group consisted of used contaminated burs.
Interestingly, the students at the
positive control school who had previously received two years of CATCH instruction showed no significant differences in their preassessment response rates to any item on the questionnaire when compared with the negative control and intervention schools.
A1, negative control; 2B, amprolium; 3C,
positive control; 4D, diclazuril; 5E, sulphachloropyrazine; and 6F, trimethoprim-sulphamethoxazole.
Positive control showed significant (P<0.0001) reduction in skin thickness to negative control after 24 hours.
Negative and
positive control PCR from first-round amplified product were used in the second round negative and
positive controls respectively.
Results showed that the mutagen MMS as the
positive control (T3) had the highest incidence of micronuclei formation in the experiment while the genotoxic treatment (T4) at 500 ppm including the negative control treatments (T1 and T2) had the lowest micronuclei counts.
Lane 1, molecular weight marker; lanes 2-4, clinical samples; lane 5, DNA
positive control for E.
(16) More recently a large (n = 300) 4-day plaque regrowth study comparing an aloe vera extract rinse to 0.2% CHG and a placebo rinse showed both the test group and
positive control to significantly (p < 0.05) reduce plaque compared to the placebo, while no statistically significant difference was demonstrated between them.
Additionally, as a
positive control, an injection of 25 [micro]l of lipopolysaccharide LPS (Sigma-Aldrich, Missouri, USA) at a concentration of 2mg/ml (50 [micro]g in total) was injected into the skin of non-tumor-bearing mice.
A commonly used commercial medical fungicide clotrimazole was used as a
positive control (standard).