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Biochemical Plant Responses to Ozone : II. Induction of Stilbene Biosynthesis in Scots Pine (Pinus sylvestris L.) Seedlings 总被引:10,自引:3,他引:7
Formation of the stilbenes pinosylvin and pinosylvin 3-methyl ether, as well as the activity of the biosynthetic enzyme stilbene synthase (pinosylvin-forming), were induced several hundred- to thousandfold in primary needles of 6-week-old pine (Pinus sylvestris L.) seedlings upon exposure to a single pulse of ozone of at least 0.15 microliters per liter. The seedlings required 4 hours of exposure as a minimum for the induction of stilbene biosynthesis when exposed to 0.2 microliters per liter ozone. Both stilbene synthase activity and stilbene accumulation increased with the duration of ozone treatment. The activity of phenylalanine ammonia-lyase and the activity of chalcone synthase, a key enzyme of the flavonoid pathway that uses the same substrates as stilbene synthase, were also stimulated about twofold by ozone. Stilbene biosynthesis appears to represent the first example of a dose-dependent biochemical response to ozone in a conifer species and may serve as a useful biomarker to study stress impacts on pine trees. 相似文献
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Filipe Manuel Clemente Rodrigo Ramirez-Campillo Daniel Castillo Javier Raya-Gonzlez Markel Rico-Gonzlez Rafael Oliveira Thomas Rosemann Beat Knechtle 《Biology of sport / Institute of Sport》2022,39(3):765
Plyometric jump training (PJT) can be used for improving balance through bilateral and unilateral jump-landing drills. Since the increased number of articles testing the effects of PJT on dynamic and static balance, it is relevant to summarize the evidence and determine the effects across different original articles. This systematic review with meta-analysis was conducted to assess the effects of PJT programs on dynamic and static balance in soccer players. The data sources utilized were Cochrane, Medline (PubMed), SPORTDiscus, and Web of Science. (i) Soccer players of any age or sex without injury, illness, or other clinical conditions; (ii) PJT-based programs restricted to a minimum of three weeks (duration); (iii) passive or active control groups; (iv) pre-post interventions values of dynamic and/or static balance; (v) randomized-controlled trials; and (vi) peerreviewed original full-text studies written in English, Portuguese, and/or Spanish. The database search initially identified 803 titles. From those, eight articles were eligible for the systematic review and meta-analysis. The results showed no significant differences between PJT and active controls in dynamic anterior, postero-medial, or postero-lateral balance for both left and right legs (p > 0.05). Additionally, no significant differences were found between PJT and active controls in terms of static balance (p = 0.495). The current evidence suggests that PJT has no significant advantage over active control groups in terms of dynamic or static balance. 相似文献
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The present study was carried out to determine the extent to which genetic factors modify the incidence of radiation-induced bone tumorigenesis in mice, and to map putative susceptibility genes. We conducted a genome-wide linkage analysis in a cohort of 47 interstrain backcrossed mice. After the mice were injected with the bone-seeking alpha-particle-emitting radionuclide (227)Th, 21 of the mice developed osteosarcomas. Two loci, one on chromosome 7 close to D7Mit145 and a second on chromosome 14 (D14Mit125), exhibited suggestive linkage to osteosarcoma predisposition, with LOD scores of 1.37 and 1.05, respectively. The LOD score increased considerably when interaction between these two loci was taken into account (LOD = 3.48). Nine of 12 mice inheriting a susceptibility allele at both loci developed osteosarcomas after (227)Th injection, compared to only four osteosarcomas in 18 animals that did not inherit either of the susceptibility alleles. Variance component analysis revealed that these genetic factors determine approximately one-fifth of the total incidence of osteosarcomas. This study demonstrates the presence of a genetic component that modulates predisposition to radiation-induced osteosarcoma. 相似文献
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Knechtle B Knechtle P Rosemann T Senn O 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(5):1312-1317
We investigated in 73 male ultraendurance mountain bikers, with (mean and SD) age 39.1 (8.6) years, weight 74.4 (8.3) kg, height 1.78 (0.07) m, and a body mass index of 23.3 (1.9) kg·m?2, whether variables of anthropometry, training, or prerace experience were associated with race time using bi and multivariate analysis. Our investigation was conducted at the "Swiss Bike Masters," which covers a distance of 120 km and an altitude of 5,000 m. In the bivariate analysis, body mass index (r = 0.29), circumference of upper arm (r = 0.28), sum of upper body skinfolds (r = 0.38), sum of lower body skinfolds (r = 0.25), sum of 8 skinfolds (r = 0.36), percent body fat (r = 0.41), total cycling kilometers per year (r = -0.47), yearly volume in both mountain bike (r = -0.33) and road cycling (r = -0.52), number of training units per week (r = -0.48), distance per unit in road cycling (r = -0.33), average speed during training in road cycling (r = -0.33), and personal best time in the "Swiss Bike Masters"(r = 0.67) were related to race time. In the multiple linear regression analysis, personal best time in the "Swiss Bike Masters" (p = 0.000), total yearly cycling kilometers (p = 0.004), and yearly training kilometers in road cycling (p = 0.017) were related to race time. When the personal best time was the dependent variable in a separate regression model, total yearly cycling kilometers (p = 0.002) remained the single predictor variable. We concluded that finishing a particular mountain bike ultramarathon does not seem to require a special anthropometry but rather a specific skill and experience for this selective kind of race coupled with a high training volume. For practical use, we concluded that successful athletes in a mountain bike ultramarathon, in a special environment and using sophisticated equipment, need prerace experience coupled with high training volume, rather than any special anthropometry. 相似文献
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Rüst CA Knechtle B Wirth A Knechtle P Ellenrieder B Rosemann T Lepers R 《The Chinese journal of physiology》2012,55(3):156-162
"The aim of this study was to investigate whether the characteristics of anthropometry, training or previous performance were related to an Ironman race time in recreational female Ironman triathletes. These characteristics were correlated to an Ironman race time for 53 recreational female triathletes in order to determine the predictor variables, and so be able to predict an Ironman race time for future novice triathletes. In the bi-variate analysis, no anthropometric characteristic was related to race time. The weekly cycling kilometers (r = -0.35) and hours (r = -0.32), as well as the personal best time in an Olympic distance triathlon (r = 0.49) and in a marathon (r = 0.74) were related to an Ironman race time (< 0.05). Stepwise multiple regressions showed that both the personal best time in an Olympic distance triathlon ( P = 0.0453) and in a marathon (P = 0.0030) were the best predictors for the Ironman race time (n = 28, r2 = 0.53). The race time in an Ironman triathlon might be partially predicted by the following equation (r2 = 0.53, n = 28): Race time (min) = 186.3 + 1.595 × (personal best time in an Olympic distance triathlon, min) + 1.318 × (personal best time in a marathon, min) for recreational female Ironman triathletes." 相似文献
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Schuster Martina Tewary Gargi Bao Xuanwen Subedi Prabal Hauck Stefanie M. Olsen Ann Karin Eide Dag Markus Trott Klaus Rüdiger Götz Sebastian Atkinson Michael J. Rosemann Michael 《Radiation and environmental biophysics》2021,60(4):689-689
Radiation and Environmental Biophysics - 相似文献
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Corinne Chmiel Oliver Reich Andri Signorell Ryan Tandjung Thomas Rosemann Oliver Senn 《PloS one》2015,10(2)
BackgroundAdequate application of guidelines concerning non-invasive ischemia testing (NIIT) could avoid inappropriate invasive testing in non-emergency situations. Hardly any data exists regarding frequency and appropriateness of diagnostic coronary angiography (CA). The aim of this study was to evaluate the proportion and predictors of patients without NIIT prior to elective purely diagnostic CA without therapeutic intervention.MethodsRetrospective cross-sectional analysis of insurance claims data from 2012 and 2013. Patients <18 years, acute cardiac ischemia and emergency procedures and patients insured in a managed care model were excluded from analysis. The proportion of patients with NIIT procedures (stress-ECG, transthoracic echocardiography, stress echocardiography, scintigraphy, computer tomography, heart MRI) undertaken within two months before diagnostic CA was assessed. Multiple logistic regression analysis was applied to investigate independent determinants for receiving NIIT.Findings2714 patients were included for analysis. 37.5% (1018) did not receive any NIIT before CA. When high risk patients (patients having received therapeutic cardiac intervention within one month after or 18 months prior to diagnostic CA, n = 766) were excluded 34.3% (669) did not receive NIIT before CA. High risk status as well as >6 chronic comorbidities were independently associated with a lower proportion of NIIT (p<0.0001, OR 0.607 and p = 0.0041, OR 0.648), when additionally controlled for age, sex, language area, insurance coverage, inpatient treatment, cardiovascular medication and lower number of chronic comorbidities. Age (p<0.05, OR 1.009) and intake of oral antiplatelet therapy (p<0.0001, OR 1.914) were independently associated with a higher proportion of NIIT when controlled for the mentioned cofactors.ConclusionsOur data show that despite the existence of guidelines a substantial overuse of a potentially harmful and inappropriate diagnostic intervention is performed suggesting the need for improvement of diagnostic pathways prior to invasive testing. 相似文献
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Anja Frei Corinne Chmiel Hansueli Schläpfer Beatrice Birnbaum Ulrike Held Johann Steurer Thomas Rosemann 《Cardiovascular diabetology》2010,9(1):23