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The purpose of this study was to evaluate factors related to caries in 6–17-year-olds in 2 groups of Norwegian counties between 1966 and 1983. The average number of surfaces filled and permanent teeth extracted due to caries declined in the 4 northern counties from 1967. An increase was recorded in the 7 southwestern counties until 1971, then a decline. In the 1960s significantly more surfaces were filled and teeth extracted in the north compared to the southwest. Based on intra-county comparisons, the decline in surfaces treated was greater in the north between 1967 and 1983; 5.4 ± 0.4 vs 3.7 ± 0.7, P < 0.01. The averages were 1.9 surfaces treated in the north and the southwest in 1983. Higher infant mortality, lower percentage of people with completed senior secondary education, and more inhabitants per doctor and per dentist in the north indicate a less favorable situation than in the southwest. School-based fluoride programs had been implemented in both groups from the mid-1960s and around 60% participated when fluoride toothpaste became freely marketed in 1971. More fluoride programs and more fluoride tablets were available to children in the north; this may indicate a preventive attitude among dentists. The decline of caries started at different times in different parts of Norway. In the rural north with the most unfavorable situation, the decline was greater and started years before fluoride toothpaste came on to the market. The early decline may partly be ascribed to the school-based fluoride programs, the continued decline to several factors.  相似文献   
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Background and purpose — Impaction bone grafting (IBG) in revision hip surgery is an established method in restoring bone stock deficiencies. We hypothesized that local treatment of the morsellized allograft with a bisphosphonate in cemented revision would, in addition to increased bone density, also reduce the early migration of the cup as measured by radiostereometry (RSA).

Patients and methods — 20 patients with aseptic cup loosening underwent revision using the IBG technique. The patients were randomized to either clodronate (10 patients) or saline (10 patients, control group) as local adjunct to the morsellized bone. The outcome was evaluated by dual-energy X-ray absorptiometry (DXA) during the first year regarding periacetabular bone density and with radiostereometric analysis (RSA) for the first 2 years regarding cup migration.

Results — 2 patients were lost to follow-up: 9 patients remained in the clodronate and 9 in the control group. Less proximal migration was found in the clodronate group compared with the controls, measured both over time (mixed-models analysis, p = 0.02) as well as at the specified time points up to 2 years (0.22?mm and 0.59?mm respectively, p = 0.02). Both groups seemed to have stabilized at 1 year. We found similar bone mineral density measured by DXA, and similar RSA migration in the other directions. No cups were re-revised.

Interpretation — Local treatment of the allograft bone with clodronate reduced early proximal migration of the revised cup but without any measurable difference in periacetabular bone density.  相似文献   
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Patients admitted to intensive care after cardiac arrest are at risk of circulatory shock and early mortality due to cardiovascular failure. The aim of this study was to evaluate the ability of the veno-arterial pCO2 difference (∆pCO2; central venous CO2 – arterial CO2) and lactate to predict early mortality in postcardiac arrest patients. This was a pre-planned prospective observational sub-study of the target temperature management 2 trial. The sub-study patients were included at five Swedish sites. Repeated measurements of ∆pCO2 and lactate were conducted at 4, 8, 12, 16, 24, 48, and 72 h after randomization. We assessed the association between each marker and 96-h mortality and their prognostic value for 96-h mortality. One hundred sixty-three patients were included in the analysis. Mortality at 96 h was 17%. During the initial 24 h, there was no difference in ∆pCO2 levels between 96-h survivors and non-survivors. ∆pCO2 measured at 4 h was associated with an increased risk of death within 96 h (adjusted odds ratio: 1.15; 95% confidence interval [CI]: 1.02–1.29; p = .018). Lactate levels were associated with poor outcome over multiple measurements. The area under the receiving operating curve to predict death within 96 h was 0.59 (95% CI: 0.48–0.74) and 0.82 (95% CI: 0.72–0.92) for ∆pCO2 and lactate, respectively. Our results do not support the use of ∆pCO2 to identify patients with early mortality in the postresuscitation phase. In contrast, non-survivors demonstrated higher lactate levels in the initial phase and lactate identified patients with early mortality with moderate accuracy.  相似文献   
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