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W J Vaartjes J N den Breejen M J Geelen S G van den Bergh 《Biochimica et biophysica acta》1980,592(1):28-37
1. Preincubation of isolated rat-liver mitochondria in the presence of adenine nucleotides or Ca2+ results in definite and persistent changes in the initial rate of pyruvate transport. 2. These changes in the rate of pyruvate transport are accompanied by equally persistent changes in the opposite direction of the activity of pyruvate dehydrogenase (EC 1.2.4.1). 3. Changes of the transmembrane pH gradient and of the membrane potential, brought about by the pretreatments of the mitochondria, cannot account for the observed changes in the rate of pyruvate transport. 4. It is proposed that the pretreatment of the mitochondria directly modulates the activity of the mitochondrial pyruvate carrier. The possible regulatory role of such a modulation system is discussed. 相似文献
85.
Adil Mardinoglu Hao Wu Elias Bjornson Cheng Zhang Antti Hakkarainen Sari M. Räsänen Sunjae Lee Rosellina M. Mancina Mattias Bergentall Kirsi H. Pietiläinen Sanni Söderlund Niina Matikainen Marcus Ståhlman Per-Olof Bergh Martin Adiels Brian D. Piening Marit Granér Nina Lundbom Jan Borén 《Cell metabolism》2018,27(3):559-571.e5
86.
Augustin Berghöfer Joshua Berger Inza Koné Ulrike Tröger Hans Ulrich Caspary 《Biodiversity and Conservation》2018,27(11):2897-2917
Ecosystem service (ES) evidence and arguments can mobilize support for biodiversity conservation. However, the ES concept’s impact on the ground seems unclear: It is reliant upon a range of pre-requisites at the science-policy nexus and it tends to be science-driven and demanding in terms of data and required capacity. The TEEB stepwise approach (The Economics of Ecosystems and Biodiversity for Local and Regional Policy Makers, Earthscan, London, 2012) guides purpose-driven ES assessments and seeks to enhance the usefulness of the ES concept in difficult real-world settings. An application of this approach has not yet been appraised. Also, beyond the instrumental use of ES data (e.g. for the design of payment schemes for ES), there is little documented experience with strategically using ES arguments for mobilizing financial resources for conservation. As many other countries, Côte d’Ivoire does not have a strong knowledge base on ecosystem services (ES). Such circumstances can preclude the use of the ES concept for convincing potential donors to co-finance conservation. We examine the recent ES assessment for the Parc national de Taï (PNT), Côte d’Ivoire, which followed the TEEB stepwise approach. We look at process, results and outcomes to address three questions: (i) How did study results contribute to mobilizing funds for the PNT? (ii) In which ways was the TEEB stepwise approach useful in practice? (iii) What lessons can be drawn for ES assessments geared to conservation finance? 相似文献
87.
Anna Bergh Constanza Bernardita Gómez Álvarez Marie Rhodin Pia Gustås 《Acta veterinaria Scandinavica》2018,60(1):81
Background
Swinging limb lameness is defined as a motion disturbance ascribed to a limb in swing phase. Little is known about its biomechanics in dogs, particularly about the body motions that accompany it, such as vertical head and pelvic motion asymmetry. The aim of this study was to describe the changes in vertical head and pelvic motion asymmetry in dogs with induced swinging limb motion disturbance, mimicking a swinging limb lameness. Fore- and hind-limb lameness was induced in ten sound dogs by placing a weight (200 g) proximal to the carpus or tarsus, respectively. Marker-based motion capture by eight infrared light emitting video cameras recorded the dogs when trotting on a treadmill. Body symmetry parameters were calculated, including differences between the two highest positions of the head (HDmax) and pelvis (PDmax) and between the two lowest positions of the head (HDmin) and pelvis (PDmin), with a value of zero indicating perfect symmetry.Results
Induction of swinging forelimb lameness showed significant changes in HDmax (median and range: sound 1.3 mm [??4.7 to 3.1], in the left side ??28.5 mm [??61.2 to ??17.9] and in the right side 20.1 mm [??4.4 to 47.5]) and, induction of swinging hind limb lameness showed significant changes in PDmax (sound 2.7 mm [??7.4 to 7.2], in the left side ??10.9 mm [??22.4 to 0.5] and in the right side 8.6 mm [??3 to 30]), as well as an increased hip movement asymmetry (sound 1.6 mm [??8.6 to 19.9], in the left side ??18.1 mm [??36.7 to 5.4] and in the right side 15 mm [??20.7 to 32.1]) (P?<?0.05).Conclusions
Induced swinging fore- and hind limb lameness resulted in significant increased asymmetry of the maximal vertical displacement movement of the head and pelvis, due to decreased lifting of the head in forelimb lameness and of the pelvis in hind limb lameness. The results suggest that asymmetry of the maximal vertical displacement of the head and pelvis (i.e. lifting) is a key lameness sign to evaluate during examination of swinging limb lameness.88.
JC. Brisset F. Gazeau C. Corot N. Nighoghossian Y. Berthezène E. Canet-Soulas M. Wiart 《IRBM》2018,39(2):93-102
Background
Inflammation is a share process in atherosclerosis and stroke and is thought to be a key player in the evolution of these diseases. Ten years ago, inflammation imaging with magnetic resonance imaging (MRI) was considered very promising for both pre-clinical and clinical studies of atherosclerosis and stroke.Contribution
We report here contributions to the field of inflammation imaging with USPIO-enhanced MRI. The goal was to investigate the life cycle of USPIOs in the body, and how the MRI signal has been impacted during their bio-interactions and bioprocessing. Those mechanisms were applied to pre-clinical longitudinal studies of inflammation in atherosclerosis and at the acute stage of ischemic stroke thus allowing the monitoring of treatment effects.Conclusion
This review presents the contribution of the collaborative research project under the “TecSan” grant from the French Research Agency (ANR) as well as pre-clinical and clinical perspectives of USPIO's inflammation MRI in atherosclerosis and stroke. 相似文献89.
Nonneutral evolution of tandem repeats in the mitochondrial DNA control region of lagomorphs 总被引:7,自引:0,他引:7
Casane D; Dennebouy N; de Rochambeau H; Mounolou JC; Monnerot M 《Molecular biology and evolution》1997,14(8):779-789
The mitochondrial DNA of the European rabbit (Oryctolagus cuniculus)
contains a tandem array of 153-bp repeats in the vicinity of the
replication origin of the H-stand. Variation among molecules in the number
of these repeats results in inter- and intraindividual length polymorphism
(heteroplasmy). Generally, in an individual, one predominant molecular type
is observed, the others representing a low percentage of the mtDNA content.
At the tissue level, we observe a particular distribution of this
polymorphism in the gonads compared with liver, kidneys, or brain, implying
a relationship between the differentiation status of the cells and the
types of new mtDNA molecules which appear and accumulate during lifetime.
Similar tandem repeats were also found in the mtDNA noncoding region of
European hares (Lepus europaeus), a cottontail (Sylvilagus floridanus), and
a pika (Ochotona rufescens). The lengths and the sequences of these units
evolve rapidly and in a concerted way, but the number of repeats is
maintained in a narrow range, and an internal 20-bp segment is highly
conserved. Constraints restrict the evolution of the primary sequence of
these repeated units, the number of which is probably controlled by a
stabilizing selection.
相似文献
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