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701.
702.
Juho-Antti Junno Sirpa Niinimäki Markku Niskanen Milton Nunez Juha Tuukkanen 《HOMO》2011,62(6):459-465
This study examines the cross sectional shape and biomechanical properties of the radial bone shaft at mid-radial tuberosity (RT) musculoskeletal marker (MSM). This information will provide insight into factors affecting bone modelling at muscle insertions. Radial shaft cross-sectional properties at radial tuberosity area (RTA) have not been previously studied. The material consists of 54 male skeletons derived from autopsies performed during the 1920s and 1930s and housed at the Central Natural History Museum, University of Helsinki. The age, sex and occupation of these individuals are known. We applied a pQCT (peripheral quantitative computed tomography) scan on the mid-site of the radial tuberosity to investigate the cross-sectional shape, the bone mineral density (BMD) and biomechanical properties. Our results indicate that bone modelling does not produce increased wall thickness or BMD at the RT site. Additionally we noticed that aging and physical activity affect the biomechanics of the RT and that the bone distribution at mid-RT is adapted to accommodate the biceps brachii muscle pull. We also found a clear association between RTA and biomechanical properties of mid-RT cross section. 相似文献
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705.
Eija M. Selkälä Sanna M. Kuusisto Tuire Salonurmi Markku J. Savolainen Matti Jauhiainen Päivi L. Pirilä Ari-Pekka Kvist Ernst Conzelmann Werner Schmitz Stefan E. Alexson Tiina J. Kotti J. Kalervo Hiltunen Kaija J. Autio 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(8):1335-1343
Bile acids play multiple roles in the physiology of vertebrates; they facilitate lipid absorption, serve as signaling molecules to control carbohydrate and lipid metabolism, and provide a disposal route for cholesterol. Unexpectedly, the α-methylacyl-CoA racemase (Amacr) deficient mice, which are unable to complete the peroxisomal cleavage of C27-precursors to the mature C24-bile acids, are physiologically asymptomatic when maintained on a standard laboratory diet. The aim of this study was to uncover the underlying adaptive mechanism with special reference to cholesterol and bile acid metabolism that allows these mice to have a normal life span. Intestinal cholesterol absorption in Amacr −/− mice is decreased resulting in a 2-fold increase in daily cholesterol excretion. Also fecal excretion of bile acids (mainly C27-sterols) is enhanced 3-fold. However, the body cholesterol pool remains unchanged, although Amacr-deficiency accelerates hepatic sterol synthesis 5-fold. Changes in lipoprotein profiles are mainly due to decreased phospholipid transfer protein activity. Thus Amacr-deficient mice provide a unique example of metabolic regulation, which allows them to have a normal lifespan in spite of the disruption of a major metabolic pathway. This metabolic adjustment can be mainly explained by setting cholesterol and bile acid metabolism to a new balanced level in the Amacr-deficient mouse. 相似文献
706.
Göran Ågren Kristina Narbro Egon Jonsson Ingmar Näslund Lars Sjöström Markku Peltonen 《Obesity (Silver Spring, Md.)》2002,10(12):1276-1283
Objective: Bariatric surgery improves cardiovascular risk factors and quality of life, but few studies have directly addressed the relation between obesity treatment and hospitalization costs. This prospective controlled study compares in-patient care between surgically and conventionally treated obese patients. Research Methods and Procedures: A total of 962 surgically and conventionally treated obese patients from the intervention study, Swedish Obese Subjects, were followed for 6 years. Changes in days of hospitalization and hospitalization costs were analyzed. Information on hospitalizations for each subject were obtained from the Swedish Hospital Discharge Register. Results: After 6 years, weight change was −16.7% in the surgical group and +0.9% in the control group (p < 0.0001). The cumulated hospital stay over 6 years was 23.4 days in the surgical group and 6.9 days in the control group (p < 0.0001). The average hospital cost for the surgical intervention was US$4300. Incremental costs that could be attributable to obesity surgery averaged US$1200 per year. After exclusion of hospitalizations for the surgical intervention and conditions common after bariatric surgery, there were no significant differences between the groups in number of hospital days or hospitalization costs. Discussion: Our experience from bariatric surgery indicates that average weight reductions of 16% will not reduce hospitalization costs over 6 years. Costs of bariatric surgery are limited and seem to be motivated given the marked improvements of cardiovascular risk factors, cardiac structure, and function and health-related quality of life. 相似文献
707.
Keret Netta M. Mutanen Marko J. Orell Markku I. Itmies Juhani H. Vlimki Panu M. 《Oecologia》2020,192(4):1085-1098
Oecologia - Climate change has shifted geographical ranges of species northwards or to higher altitudes on elevational gradients. These changes have been associated with increases in ambient... 相似文献
708.
We studied the effect of winter rank on survival rate and reproductive success in Willow Tits Parus montanus, a resident passerine living in dominance-structured flocks during the nonbreeding season, in 6 years. Winter survival was dependent on both the birds' age and rank. Adults survived better than first-year birds, and within first-year males, dominants survived better than subordinates. In other sex and age classes, rank did not contribute to survival. Although first-year males were in excess among nonbreeders, no connection existed between breeding status and rank. Female rank did not explain the variation in the start of laying, clutch size, number of fledglings or recruit production. We conclude that social status in Willow Tits affects individual fitness mainly through rank-dependent survival. Acquiring a high rank position seems to be most important for first-year birds, especially first-year males. 相似文献
709.
Effect of habitat, date of laying and density on clutch size of the Great Tit Parus major in northern Finland 总被引:1,自引:0,他引:1
The sizes of 1034 Great Tit clutches were studied at the Oulu area (c. 65°N, 25°30'E) in northern Finland. The average size was 9.86 eggs in the first clutch and 7.51 in the second in 13 study areas. The decrease in clutch size from the first to the second laying was most pronounced in those females laying the largest first clutches.
Irrespective of habitat, the clutch size was larger in the sparsely populated areas than in the densest area (Taskila). The clutch size decreased according to the season in all the areas, but this was not as pronounced in Taskila as in the other areas.
The annual average size of the first clutches was inversely related to the breeding density and pronouncedly so to the mean dale of laying. The latter was suggested to be an adaptation to the short season in the northern areas.
An analysis of data from 27 study areas in Europe, north of the Mediterranean region, suggests that the clutch size does not vary with latitude or longitude. 相似文献
Irrespective of habitat, the clutch size was larger in the sparsely populated areas than in the densest area (Taskila). The clutch size decreased according to the season in all the areas, but this was not as pronounced in Taskila as in the other areas.
The annual average size of the first clutches was inversely related to the breeding density and pronouncedly so to the mean dale of laying. The latter was suggested to be an adaptation to the short season in the northern areas.
An analysis of data from 27 study areas in Europe, north of the Mediterranean region, suggests that the clutch size does not vary with latitude or longitude. 相似文献
710.