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51.
OBJECTIVE: Evaluate the physical fitness and training of Norwegian infantry soldiers during 10 months of compulsory military service. METHODS: Maximal oxygen uptake (VO2max) and maximal numbers of sit-ups, push-ups, and chin-ups and 3-km running time were tested in 107 male infantry soldiers at the beginning and end of basic training (BT), and again at demobilization. The amount of physical training was registered throughout the military service. RESULTS: During BT, major improvements in sit-ups and push-ups were found. VO2max increased in soldiers with the lowest initial VO2max, but decreased to pre-BT level at demobilization. The amount of obligatory physical training was 8.5 hours x week(-1) during BT and 35% lower after BT, and was usually performed in uniform at low to moderate intensity. CONCLUSION: The amount of high-intensity endurance and strength training during compulsory military service is to low to improve the soldiers' endurance and muscular strength.  相似文献   
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53.
The aim of the study was to compare the frequency-specific effects of noise on hearing acuity across the range 250-8000 Hz and the extent to which the patterns of frequency-specific threshold shifts differ between occupational noise and impulse noise. Pure-tone audiometry was administered to an adult general population sample with 51 975 subjects who also provided questionnaire information about noise exposure and other risk factors. Threshold shifts induced by life-long occupational noise and impulse noise (mostly shooting) were estimated separately in six age and sex groups for eight frequencies. Reported noise exposure, as well as observed threshold shifts, were moderate among women. Threshold shifts averaged over both ears among subjects in the higher 2% of exposure to occupational noise, reached 13 dB (3000 Hz, age 65 years + ) among men and were generally largest at 3000-4000 Hz. The shifts induced by impulse noise reached approximately 8 dB among men 45-64 years and men 65 years+. The effects of impulse noise were strongest at 3000-8000 Hz and varied little within this frequency range.  相似文献   
54.
7,8-dihydro-8-oxo-guanine (8-oxoG) is a mutagenic DNA lesion that is induced by ultraviolet A (UVA) radiation. 8-oxoG results in increased frequency of GC-->TA transversion mutations. UVA-induced mutant frequency was measured in the guanine phosphoribosyl transferase (gpt) gene of Chinese hamster ovary cells (AS52) that were stably transfected to overexpress the hOGG1 protein, the human DNA repair glycosylase for 8-oxoG. This mutant frequency was compared with ultraviolet A-induced mutant frequency in AS52 cells stably transfected with the same vector without the hOGG1 gene. The mutant frequency was significantly decreased in the hOGG1 overexpressing cells irradiated with 300 and 400 kJ/m2 ultraviolet A radiation, corresponding to 25% and 10% cell survival, respectively. The hOGG1 overexpressing cells repaired oxidative DNA lesions three times faster than the vector only cells as measured by a semi-automated alkaline elution assay using FPG enzyme, the bacterial OGG1 analogue, to cut DNA at oxidative base modifications. Thus, the lower mutation frequency in UVA-induced mutations of the hOGG1 overexpressing cells may be related to the increased repair of 8-oxoG. No GC-->TA mutations were detected in the UVA-irradiated hOGG1 overexpressing cells. The results suggest a link between the 8-oxoG lesion and UVA-induced mutagenesis. We propose that hOGG1 has a role in maintaining genomic stability in mammalian cells after oxidative stress.  相似文献   
55.
By employing a common protocol and data from electronic health registries in Denmark, Navarre (Spain), Norway and Portugal, we estimated vaccine effectiveness (VE) against hospitalisation due to COVID-19 in individuals aged ≥ 65 years old, without previous documented infection, between October 2021 and March 2022. VE was higher in 65–79-year-olds compared with ≥ 80-year-olds and in those who received a booster compared with those who were primary vaccinated. VE remained high (ca 80%) between ≥ 12 and < 24 weeks after the first booster administration, and after Omicron became dominant.  相似文献   
56.
When exercising with a small muscle mass, the mass-specific O2 delivery exceeds the muscle oxidative capacity resulting in a lower O2 extraction compared with whole-body exercise. We elevated the muscle oxidative capacity and tested its impact on O2 extraction during small muscle mass exercise. Nine individuals conducted six weeks of one-legged knee extension (1L-KE) endurance training. After training, the trained leg (TL) displayed 45% higher citrate synthase and COX-IV protein content in vastus lateralis and 15%-22% higher pulmonary oxygen uptake ( ) and peak power output ( ) during 1L-KE than the control leg (CON; all P < .05). Leg O2 extraction (catheters) and blood flow (ultrasound Doppler) were measured while both legs exercised simultaneously during 2L-KE at the same submaximal power outputs (real-time feedback-controlled). TL displayed higher O2 extraction than CON (main effect: 1.7 ± 1.6% points; P = .010; 40%-83% of ) with the largest between-leg difference at 83% of (O2 extraction: 3.2 ± 2.2% points; arteriovenous O2 difference: 7.1 ± 4.8 mL· L−1; P < .001). At 83% of , muscle O2 conductance (DMO2; Fick law of diffusion) and the equilibration index Y were higher in TL (P < .01), indicating reduced diffusion limitations. The between-leg difference in O2 extraction correlated with the between-leg ratio of citrate synthase and COX-IV (r = .72-.73; P = .03), but not with the difference in the capillary-to-fiber ratio (P = .965). In conclusion, endurance training improves O2 extraction during small muscle mass exercise by elevating the muscle oxidative capacity and the recruitment of DMO2, especially evident during high-intensity exercise exploiting a larger fraction of the muscle oxidative capacity.  相似文献   
57.
Public acceptance and awareness of an HIV/AIDS information campaignin Norway were studied using empirical data from a nationwideinterview survey (N = 1066) of adult Norwegians aged 15 yearsand above. ‘The condom campaign’ was a $100 000campaign displayed on billboards, posters and postcards throughoutNorway. A total of 60% of the population accepted this kindof sexual information and 70% had noticed it. The most importantpredictors of acceptance were in rank order: education, politicalpreference, age, interpersonal communication and geographicregion, and these factors explained 16% of the variance. Themost important predictors of awareness of the campaign were:acceptance, age, education, interpersonal communication andurbanization, explaining 16% of the variance in awareness. Acceptanceof the campaign corresponds closely to the religious-moralisticaxis in Norwegian politics, and seems to influence the awarenessof the campaign through a personal process related either toselective or voluntary exposure. Personal relevance and discussionwith friends and family influence awareness. Thus, personalrelevance and communication utility seem to be important inthe communication of HIV/AIDS information to the public.  相似文献   
58.
This longitudinal study of 231 preschoolchildren from a medium sized Norwegian town had three aims: firstly, to examine the children's early dental behavior, secondly to study the variation of dental health behavior according to mother's education, mother's dental health, and her dental attendance pattern, and thirdly to identify any behavioral or social predictors of dental caries in 36-month-old children. Data were collected at health centers, using precoded questionnaires and examinations, when the children were 6, 18, and 36 months old. Data about the mothers were collected at the maternity ward. At 36 months of age, 80% of the children were caries free. Favorable dental behaviors were related to toothbrushing and use of fluorides. These behaviors were so well established and consistent at all ages that they can be regarded as norms for this community. The most unfavorable and inconsistent behavior was related to sugar consumption. Dental health education could be most usefully applied to this area, where the greatest potential for improvement in behavior exists. A relationship was found between the children's caries experience and the number of missing teeth of the mother, her dental attendance pattern and her level of education. None of the social or behavioral variables tested had a strong enough association with caries experience to justify their use as caries predictors in this age group.  相似文献   
59.
The efficacy of manganese ions (Mn2+) as intracellular (ic) contrast agents was assessed in rat myocardium. T1 and T2 and Mn content were measured in ventricular tissue excised from isolated perfused hearts in which a 5-min wash-in with 0, 30, 100, 300, or 1000 microM of Mn dipyridoxyl diphosphate (MnDPDP) was followed by a 15-min wash-out to remove extracellular (ec) Mn2+. An inversion recovery (IR) analysis at 20 MHz revealed two T1 components: an ic and short T1-1 (650-251 ms), and an ec and longer T1-2 (2712-1042 ms). Intensities were about 68% and 32%, respectively. Tissue Mn content correlated particularly well with ic R1-1. A two-site water-exchange analysis of T1 data documented slow water exchange with ic and ec lifetimes of 11.3 s and 7.5 s, respectively, and no differences between apparent and intrinsic relaxation parameters. Ic relaxivity induced by Mn2+ ions in ic water was as high as 56 (s mM)(-1), about 8 times and 36 times higher than with Mn2+ aqua ions and MnDPDP, respectively, in vitro. This value is as high as any reported to date for any synthetic protein-bound metal chelate. The increased rotational correlation time (tauR) between proton and electron (Mn2+) spins, and maintained inner-sphere water access, might make ic Mn2+ ions and Mn2+ -ion-releasing contrast media surprisingly effective for T1-weighted imaging.  相似文献   
60.
In the adult Norwegian population there is substantial support for the expansion of public programs for old-age pensioners. However, the perception of old-age pensioners concerning dental services as social welfare institutions is practically unknown. The purpose of this study was to provide some tentative data on this sociopolitical tissue. As part of a field experiment on delivery of dental services for old-age pensioners in the county of Troms, the old-age pensioners of one municipality (n = 572) were asked about which strategy public authorities should adhere to when allocating dental care resources to old-age pensioners. About 40% favored equal opportunities for all, while about 50% preferred dental services based upon need. This indicates a pattern of polarization, but this was not confirmed in a multivariate analysis (R2 = 0.01), which might be interpreted as indifference to the issue on the part of a majority of the pensioners. Only one subgroup deviated significantly from the aggregate distribution: of those who were negative to the pensioner role, 68% favored need-based dental services.  相似文献   
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