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1.
Kari Aalto Teddy Holmstr m Erkki Karaharju Jaakko Joukainen Pekka Paavolainen Par Sl tis 《Acta orthopaedica》1987,58(1):66-70
Bone repair was studied in the rabbit tibiofibular bone after a midshaft transverse osteotomy stabilized by external fixation and heavy compression. Both subendosteal and subperiosteal callus formation with concomitant contact healing were observed within 3 weeks, and were further succeeded by subendosteal resorption and increased porosis resulting in atrophy of the cortical bone. Subjected to the torsion test, the bones exhibited restoration of strength within 3 weeks, with maximal energy absorption and elasticity at 6 weeks. The failure of the osteotomy in the torsion test, with radiographic visibility of the osteotomy, characterized the soft-tissue type of behavior of the bones. Hard-tissue like behaviour of the bones with resistance to torsion at the osteotomy site and radiographic obliteration of the osteotomy line occurred by 12 weeks, indicating complete union of the osteotomy. Our experiments demonstrate that elastic external fixation is preferable to the rigid compression plate. 相似文献
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Thomas Zeiler MD Antti Taivainen MD PhD Marja Rytkönen PhD Jaakko Rautiainen MSc Henry Karjalainen PhD Rauno Mäntjärvi MD PhD Leena Tuomisto MD PhD Tuomas Virtanen MD PhD 《The Journal of allergy and clinical immunology》1997,100(6):721-727
Background: Lately, renewed interest has arisen in the new forms of allergen immunotherapy because they may offer alternatives for drug treatment. Objective: The purpose of this study was to develop a well-characterized preparation of the main respiratory cow dander allergen, Bos d 2, with attenuated allergenic activity. Methods: The immunologic characteristics of Bos d 2 preparations were studied by indirect IgE ELISA, ELISA inhibition, Western blotting, histamine release, skin prick tests, and the proliferation tests of allergen-specific T-cell clones. Results: The complete recombinant Bos d 2 was observed to bind effectively, IgE of cow-allergic patients in indirect ELISA. In other experiments, the IgE-binding capacity of recombinant Bos d 2 proved to be lower compared with native Bos d 2. When the two overlapping recombinant fragments of Bos d 2 (corresponding amino acids 1-131 and 81-172, respectively) covering the whole molecule were compared with the complete recombinant Bos d 2 with several methods, only a low level of residual reactivity was observed. For example, recombinant fragments could not bind antibody at all in ELISA inhibition tests retaining, however, some reactivity in skin prick tests. In contrast, the fragments were able to stimulate vigorously Bos d 2-specific T-cell clones. Conclusion: The approach we have taken may offer a simple and reproducible way to produce hypoallergenic preparations for immunotherapy, circumventing simultaneously some of the problems of other experimental methods such as individual T-cell epitope recognition in peptide-based immunotherapy. (J Allergy Clin Immunol 1997;100:721-7.) 相似文献
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We have earlier introduced a principle for learning metrics, which shows how metric-based methods can be made to focus on discriminative properties of data. The main applications are in supervising unsupervised learning to model interesting variation in data, instead of modeling all variation as plain unsupervised learning does. The metrics are derived by approximations to an information-geometric formulation. In this paper, we review the theory, introduce better approximations to the distances, and show how to apply them in two different kinds of unsupervised methods: prototype-based and pairwise distance-based. The two examples are self-organizing maps and multidimensional scaling (Sammon's mapping). 相似文献
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Males ofDrosophila littoralis vibrate their wings during courtship to deliver a love song. This consists of 25- to 50-ms-long pulses with a basic frequency of about 250–400 Hz, separated by 250- to 500-ms pauses. When recording the sounds of flies from several localities in Europe, we found that males of one strain from northern Finland displayed courtship sounds with an unusally low wing beat frequency (below 250 Hz). In a genetic analysis utilizing marker stocks, the anomalous frequency was found to be caused by genes on all major autosomes, the strongest factors being on the second chromosome. Interaction between genes on chromosome 2 and on the fused chromosome 3–4 was nonadditive. In low-frequency sounds, the number of cycles in the pulse (CN) was decreased, so that the length of the sound pulse (PL) remained more or less unchanged. We suggest that the genetically and physiologically most thoroughly controlled trait in the sound ofDrosophila littoralis is the length of the pulse. 相似文献
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Kirsten Mehlig Christopher Holmberg Leonie H. Bogl Eva Erhardt Charalambos Hadjigeorgiou Antje Hebestreit Jaakko Kaprio Fabio Lauria Nathalie Michels Iris Pigeot Lucia A. Reisch Toomas Veidebaum Lauren Lissner 《Obesity facts》2021,14(1):121
BackgroundDuring adolescence, health behaviors and weight status are increasingly influenced by friendship and peer networks. This paper examines resemblances in weight-related characteristics and how they differ by sociodemographic factors.MethodsOver 3,000 friendships were reported by 1,603 adolescents, aged 11–16 years, who participated in the school-based I. Family study in 6 European countries. Each “source child” named 1–10 friends for whom standardized weight-related traits were available in the same survey. The mean value of the friends'' traits weighted by time spent together was calculated, and related to the source child''s trait. Country, age and sex of the source child, parental education, and immigrant background were considered for confounding and moderation.ResultsSource children''s z-scores of body fat percent and BMI were positively associated with their friends'' characteristics, in particular if they had highly educated parents. Positive associations were also found regarding the frequency of fast-food consumption, impulsivity, screen time, preference for sugar-sweetened foods, and hours spent in sports clubs, in increasing order of effect size. Additionally, correlations were observed between friends'' cognitive and school functioning and being bullied. No associations were seen for a preference for high-fat foods, weight concerns, and health-related quality of life. Finally, parental education and immigrant background were associated between friends in all countries except Sweden, where no associations were observed.ConclusionAdolescent friends shared a number of weight-related characteristics. For weight measures per se, positive associations with friends'' characteristics were only observed in adolescents with high parental education. Associations regarding energy-balance behaviors and indicators of school-related well-being did not differ by parental education. Parental education and immigrant background correlated positively in friends in most countries showing that social aggregation is already occurring in adolescence. The wide spectrum of friendship associations in weight-related traits and behaviors suggests that health promotion initiatives in adolescents should be directed towards peer groups in both school-related and leisure-time environments.ISRCTN RegistryPan-European IDEFICS/I. Family children cohort (ID ISRCTN62310987; https://doi.org/10.1186/ISRCTN62310987). 相似文献
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OBJECTIVES: Our aim was to study heritability, risk factors and hospitalization for uterine fibroids. METHODS: A random sample of 80 MZ and 80 DZ twins from the Finnish Twin Cohort were invited and 51% of the eligible women (n=82, 17 MZ and 16 DZ pairs, 40-47 years, mean age 43.0), underwent a transvaginal ultrasound. The entire cohort of 13872 women was linked to the national hospital discharge registry 1972-1990. RESULTS: Prevalence of fibroids was 66% and the average number of fibroids 1.7. The casewise concordance for being hospitalized for uterine fibroids was higher in MZ (0.31, 95% CI 0.24-0.37) than in DZ pairs (0.18, 95% CI 0.14-0.22). The proportion of variance in liability to fibroid hospitalization accounted for by genetic factors was 54.8% (95% CI 46.2-62.7%). Women with fibroids had higher body mass index (23.7 vs 21.7, P=0.0086), lower age at first birth (25.7 vs 29.3, P=0.012) and higher parity (3+ children 48.2 vs 29.6%, P=0.009) than women without fibroids. Risk ratio (RR) for fibroids in a MZ twin whose sister had been diagnosed with fibroids was 1.1 (95% CI 0.08;15), for a DZ twin 1.1 (95% CI 0.16;8.8) and for all twins 1.3 (95% CI 0.3; 6.1). Intraclass correlation for the number of fibroids was 0.24 for MZ and 0.11 for DZ twins, yielding an heritability estimate of 0.26. CONCLUSION: Reproductive and anthropometric factors may have at least as large role in pathogenesis of fibroids than genetic factors. 相似文献
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Jukka Kemppainen Sargo Aalto Toshihiko Fujimoto Kari K. Kalliokoski Jaakko Långsjö Vesa Oikonen Juha Rinne Pirjo Nuutila Juhani Knuuti 《The Journal of physiology》2005,568(1):323-332
Physiological activation increases glucose uptake locally in the brain. However, it is not known how high intensity exercise affects regional and global brain glucose uptake. The effect of exercise intensity and exercise capacity on brain glucose uptake was directly measured using positron emission tomography (PET) and [18 F]fluoro-deoxy-glucose ([18 F]FDG). Fourteen healthy, right-handed men were studied after 35 min of bicycle exercise at exercise intensities corresponding to 30, 55 and 75% of on three separate days. [18 F]FDG was injected 10 min after the start of the exercise. Thereafter exercise was continued for another 25 min. PET scanning of the brain was conducted after completion of the exercise. Regional glucose metabolic rate (rGMR) decreased in all measured cortical regions as exercise intensity increased. The mean decrease between the highest and lowest exercise intensity was 32% globally in the brain (38.6 ± 4.6 versus 26.1 ± 5.0 μmol (100 g)−1 min−1 , P < 0.001). Lactate availability during exercise tended to correlate negatively with the observed brain glucose uptake. In addition, the decrease in glucose uptake in the dorsal part of the anterior cingulate cortex (37% versus 20%, P < 0.05 between 30% and 75% of ) was significantly more pronounced in subjects with higher exercise capacity. These results demonstrate that brain glucose uptake decreases with increase in exercise intensity. Therefore substrates other than glucose, most likely lactate, are utilized by the brain in order to compensate the increased energy needed to maintain neuronal activity during high intensity exercise. Moreover, it seems that exercise training could be related to adaptive metabolic changes locally in the frontal cortical regions. 相似文献
10.
Vitamin C and other compounds in vitamin C rich food in relation to risk of tuberculosis in male smokers. 总被引:1,自引:0,他引:1
H Hemil? J Kaprio P Pietinen D Albanes O P Heinonen 《American journal of epidemiology》1999,150(6):632-641
To examine whether vitamin C rich food consumption and related vitamin C intake are associated with the risk of tuberculosis, the authors analyzed 167 incident cases of tuberculosis during a median follow-up time of 6.7 years in a clinical trial cohort of 26,975 Finnish men for whom they had baseline dietary data. A highly statistically significant inverse association between calculated vitamin C intake and the incidence of tuberculosis was found, but adjustment for non-dietary factors weakened the association to nonsignificant. Furthermore, the risk of tuberculosis decreased with increasing intake of fruits, vegetables, and berries independent of vitamin C intake. Subjects who had dietary vitamin C intake >90 mg/day and who consumed more than the average amount of fruits, vegetables, and berries had a significantly lower risk of tuberculosis (adjusted relative risk = 0.40; 95% confidence interval 0.24, 0.69). Associations between dietary vitamin C intake and occurrence of various diseases without proper control of confounding have often been interpreted as causal. These findings show that such associations can be confounded even by some other dietary components. Lower tuberculosis incidence in subjects who consumed more fruits, vegetables, and berries poor in vitamin C suggests that other compounds in such a diet may reduce the risk of tuberculosis. 相似文献