Effective dose equivalent comparison with

In comparison with the average effective dose equivalent to the general population from cosmic radiation, which approximates 0.27 mSv (27 mrem) annually, the average dose to the thorax of an individual from a standard x-ray examination of the chest is of the order of 0.10 mSv (10 mrem). Other diagnostic procedures may deliver substantially larger doses, e.g., the average effective dose equivalent of an individual from a barium enema examination of the colon is approximately 4 mSv (400 mrem). 

Table 2.10 shows a comparison of the fallout at Seascale, Cumbria, from the Windscale accident and the fallout in the Munich area from Chernobyl, together with estimates of the effective dose equivalent received by people in those areas at the relevant time (Crick Linsley, 1982,1983 Doerfel Piesch, 1987). The doses at Seascale are extrapolated to 50 a from the accident to allow for long-term contributions, mainly from 137Cs. The doses at Munich are for the first year only, and should be increased by about 50% to give the life-time dose (Clarke, 1987). 

The dose to bone included a relative damage factor, n, in addition to the quality factor, QF (then termed RBE). The n factor represented the relative effectiveness of the dose from the radionuclide as compared with the dose equivalent from 226Ra. The assumptions used by both NCRP and ICRP in making this comparison of bone seeking radio-... 

One bolus injection of KRN5500 did not show any significant antitumor activity on HT-29 xenografts in comparison with the control, whereas the equivalent dose of KRN/m was significantly superior to the control. However, there was no statistically significant difference between the effects of these two drugs (Fig 11)... 

Novel mechanisms of interest include sensitizing hypoxic tumor cell lines to enhance radiotoxicity. Tirapazamine is a hypoxia-selective compound 1-2-fold greater in magnitude in comparison to mitomycin C or porfiromycin (84). Its mechanism of action results in a one-electron reduction inducing DNA double-strand breaks and cell death under hypoxic conditions. The free radical is oxidized back to the parent compound under aerobic conditions. When combined with the platinum compounds, the cytotoxic effects may be equivalent to that seen with five times the dose of cisplatin without the toxicities that would be encountered if actually administered (85). 

Venlafaxine extended-release, a serotonin-norepinephrine reuptake inhibitor (SNRI), alleviates anxiety in patients with and without co-morbid depression. The reduction in psychic symptoms of anxiety and tension is not accompanied by significant reductions in somatic symptoms. Venlafaxine (dosed once daily) was effective at doses of 150 and 225 mg for 2 months in patients with GAD, and efficacy was maintained for an additional 6 months of therapy." Paroxetine was significantly more effective than placebo at achieving response in 62% and 68% of patients at 20 and 40 mg daily, respectively, after 2 months. Remission occurred in 30% and 36% of patients taking 20 and 40 mg of paroxetine, respectively." Escitalopram was more efficacious than placebo in three 8-week trials in patients with GAD. In a four paraUel-group comparison, diazepam and trazodone were found to be equivalent in anxiolytic activity (remission rates of 66% and 69%, respectively) compared with placebo (47% remission rate), but rmipramine s rate of remission (73%) exceeded that of the other three treatments. ... 

The thrombolytic effect in vivo was studied in rabbits with a radioactive thrombus produced in the inferior vena cava. The radioactivity over the occluded venous segment was measured by a scintillation probe fitted with a collimator adapted to the anatomical conditions. Comparison of equivalent doses of urokinase and benzoyl-urokinase in the model of venous thrombosis showed that the acylated form of the enzyme was more active than the free enzyme [38). 

Fifty milligrams of meperidine shows no superiority over placebo but a 100 mg dose is comparable to 10-15 mg morphine. Following IM administration, onset of analgesia occurs within 10-15 minutes and peak effects occur within 1 hour. In a comparison of three doses of meperidine compared to three equipotent doses of morphine delivered via PCA, meperidine demonstrated equivalent analgesia at rest but morphine was superior with activity. These data have been replicated by others. In children, PCA morphine produced significantly better pain scores than meperidine with no difference in the side-effect profiles [1]. Low doses of meperidine, 12.5 mg, are used effectively to treat post-operative shivering and the shivering induced by an infusion of amphotericin. 

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