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991.
Thompson CJ Cobb KM Blackwell J 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(1):131-137
Functional training programs have been used in a variety of rehabilitation settings with documented success. Based on that success, the concept of functional training has gained popularity in applied fitness settings to enhance sport performance. However, there has been little or no research studying the efficacy of functional training programs on the improvement of sport performance or functional fitness. Thus, it was the purpose of this study to determine the effect of a progressive functional training program on club head speed and functional fitness in older male golfers. Eighteen male golfers (age: 70.7 +/- 9.1 [SD] years) were randomly assigned to an exercise (N = 11) or control (N = 7) group. The exercise group participated in an 8-week progressive functional training program including flexibility exercises, core stability exercises, balance exercises, and resistance exercises. Pre- and postmeasurements included club head speed of a driver by radar (exercise and Control) and Fullerton Senior Fitness Test measurements (exercise only). One-way analysis of covariance was performed on club head speed measurements using pretest measurements as the covariate. Paired t-tests were performed to analyze Senior Fitness Test variables. After the intervention, maximal club head speed increased in the exercise group (127.3 +/- 13.4 to 133.6 +/- 14.2 km x hr(-1)) compared with the control group (134.5 +/- 14.6 to 133.3 +/- 11.2 km x hr(-1); p < 0.05). Additionally, improvements (p < 0.05) were detected for most Senior Fitness Test variables in the exercise group. In summary, this functional training program resulted in significant improvements in club head speed and several components of functional fitness. Future research should continue to examine the effect of functional training programs on sport performance and functional fitness in older adults. 相似文献
992.
Question: What relationship exists between productivity, plant species richness and livestock diet? Are the results dependent on scale? Location: A sheep‐grazed Koelerio‐Corynephoretea sandy habitat of the northern upper Rhine (Germany) as a low productivity model system. Methods: The investigation was carried out for three years at a fine scale (2 m2) and for two years at a broad scale (79 m2). Productivity was measured by means of weighed above‐ground phytomass for fine scale and colour‐infrared (CIR) aerial photographs of the same system for fine and broad scales. For both scales, total numbers of vascular plant species and numbers of endangered vascular plant species were extracted from current vegetation relevés. Additionally, we obtained data on livestock diet (grazed phytomass, crude protein content). Results: Statistical analyses show an influence of the year on all variables; relationships between variables are not significant in every year. Species richness and number of endangered species are negatively related to productivity at fine scale while crude protein content and grazed phytomass are positively related to productivity. At the broad scale the diversity‐productivity relationship shows a ‘hump’ with highest species numbers in middle pioneer stages; numbers of endangered species are highest in all pioneer stages. Conclusions: We found a strong impact of scale and year on the diversity‐productivity relationship. It is inappropriate to analyse only small plots (2 m2), and it is necessary to study different years. This vegetation complex is dependent on grazing impact; thus there is an inversely proportional relationship between nature conservation value (high diversity) and livestock nutrition. 相似文献
993.
994.
Inhaled nebulized nitrite is a hypoxia-sensitive NO-dependent selective pulmonary vasodilator 总被引:11,自引:0,他引:11
Hunter CJ Dejam A Blood AB Shields H Kim-Shapiro DB Machado RF Tarekegn S Mulla N Hopper AO Schechter AN Power GG Gladwin MT 《Nature medicine》2004,10(10):1122-1127
The blood anion nitrite contributes to hypoxic vasodilation through a heme-based, nitric oxide (NO)-generating reaction with deoxyhemoglobin and potentially other heme proteins. We hypothesized that this biochemical reaction could be harnessed for the treatment of neonatal pulmonary hypertension, an NO-deficient state characterized by pulmonary vasoconstriction, right-to-left shunt pathophysiology and systemic hypoxemia. To test this, we delivered inhaled sodium nitrite by aerosol to newborn lambs with hypoxic and normoxic pulmonary hypertension. Inhaled nitrite elicited a rapid and sustained reduction ( approximately 65%) in hypoxia-induced pulmonary hypertension, with a magnitude approaching that of the effects of 20 p.p.m. NO gas inhalation. This reduction was associated with the immediate appearance of NO in expiratory gas. Pulmonary vasodilation elicited by aerosolized nitrite was deoxyhemoglobin- and pH-dependent and was associated with increased blood levels of iron-nitrosyl-hemoglobin. Notably, from a therapeutic standpoint, short-term delivery of nitrite dissolved in saline through nebulization produced selective, sustained pulmonary vasodilation with no clinically significant increase in blood methemoglobin levels. These data support the concept that nitrite is a vasodilator acting through conversion to NO, a process coupled to hemoglobin deoxygenation and protonation, and evince a new, simple and inexpensive potential therapy for neonatal pulmonary hypertension. 相似文献
995.
Liebscher M Jahreis G Lücke C Grabley S Raina S Schiene-Fischer C 《The Journal of biological chemistry》2007,282(7):4437-4446
We have reported that the hsp70 chaperone DnaK from Escherichia coli might assist protein folding by catalyzing the cis/trans isomerization of secondary amide peptide bonds in unfolded or partially folded proteins. In this study a series of fatty acylated benzamido inhibitors of the cis/trans isomerase activity of DnaK was developed and tested for antibacterial effects in E. coli MC4100 cells. N(alpha)-[Tetradecanoyl-(4-aminomethylbenzoyl)]-l-asparagine is the most effective antibacterial with a minimal inhibitory concentration of 100 +/- 20 microg/ml. The compounds were shown to compete with fluorophore-labeled sigma(32)-derived peptide for the peptide binding site of DnaK and to increase the fraction of aggregated proteins in heat-shocked bacteria. Despite its inability to serve as a folding helper in vivo a DnaK-inhibitor complex was still able to sequester an unfolded protein in vitro. Structure activity relationships revealed a distinct dependence of DnaK-assisted refolding of luciferase on the fatty acyl chain length, whereas the minimal inhibitory concentration was most sensitive to the structural nature of the benzamido core. We conclude that the isomerase activity of DnaK is a major survival factor in the heat shock response of bacteria and that small molecule inhibitors can lead to functional inactivation of DnaK and thus will display antibacterial activity. 相似文献
996.
997.
Wulf-Peter?SchmidtEmail author Elisabeth?Dahlqvist Matthias?Finkbeiner Stephan?Krinke Silvia?Lazzari Dirk?Oschmann Sophie?Pichon Christian?Thiel 《The International Journal of Life Cycle Assessment》2004,9(6):405-416
Goal, Scope and Background The automotive industry has a long history in improving the environmental performance of vehicles - fuel economy and emission
improvements, introduction of recycled and renewable materials, etc. The European Union also aims at improving the environmental
performance of products by reducing, in particular, waste resulting from End-of-Life Vehicles (ELVs) for example. The European
Commission estimates that ELVs contribute to approximately 1 % of the total waste in Europe [9]. Other European Union strategies
are considering more life cycle aspects, as well as other impacts including resource or climate change. This article is summarizing
the results of a European Commission funded project (LIRECAR) that aims at identifying the environmental impacts and relevance
for combinations of recycling / recovery and lightweight vehicle design options over the whole life cycle of a vehicle - i.e.
manufacturing, use and recycling/recovery. Three, independent and scientific LCA experts reviewed the study according to ISO
14040. From the beginning, representatives of all Life Cycle Stakeholders have been involved (European materials & supplier
associations, an environmental Non-Governmental Organization, recycler’s association).
Model and System Definition The study compared 3 sets of theoretical vehicle weight scenarios: 1000 kg reference (material range of today’s end-of-life,
mid-sized vehicles produced in the early 1990’s) and 2 lightweight scenarios for 100 kg and 250 kg less weight based on reference
functions (in terms of comfort, safety, etc.) and a vehicle concept. The scenarios are represented by their material range
of a broad range of lightweight strategies of most European car manufacturers. In parallel, three End-of-Life (EOL) scenarios
are considered: EOL today and two theoretical extreme scenarios (100% recycling, respectively, 100% recovery of shredder residue
fractions that are disposed of today). The technical and economical feasibility of the studied scenarios is not taken into
consideration (e.g. 100% recycling is not possible).
Results and Discussion Significant differences between the various, studied weight scenarios were determined in several scenarios for the environmental
categories of global warming, ozone depletion, photochemical oxidant creation (summer smog), abiotic resource depletion, and
hazardous waste. However, these improvement potentials can be only realized under well defined conditions (e.g. material compositions,
specific fuel reduction values and EOL credits) based on case-by-case assessments for improvements over the course of the
life cycle. Looking at the studied scenarios, the relative contribution of the EOL phase represents 5% or less of the total
life cycle impact for most selected impact categories and scenarios. The EOL technology variations studied do not impact significantly
the considered environmental impacts. Exceptions include total waste, as long as stockpile goods (overburden, tailings and
ore/coal processing residues) and EOL credits are considered.
Conclusions and Recommendations LIRECAR focuses only on lightweight/recycling, questions whereas other measures (changes in safety or comfort standards, propulsion
improvements for CO2, user behavior) are beyond the scope of the study. The conclusions are also not necessarily transferable to other vehicle
concepts. However, for the question of end-of-life options, it can be concluded that LIRECAR cannot support any general recommendation
and/or mandatory actions to improve recycling if lightweight is affected. Also, looking at each vehicle, no justification
could be found for the general assumption that lightweight and recycling greatly influence the affected environmental dimension
(Global Warming Potential or resource depletion and waste, respectively). LIRECAR showed that this general assumption is not
true under all analyzed circumstances and not as significant as suggested. Further discussions and product development targets
shall not focus on generic targets that define the approach/technology concerned with how to achieve environmental improvement
(weight reduction [kg], recycling quota [%]), but on overall life cycle improvement). To enable this case-by-case assessment,
exchanges of necessary information with suppliers are especially relevant. 相似文献
998.
Bachmann M Kosan C Xing PX Montenarh M Hoffmann I Möröy T 《The international journal of biochemistry & cell biology》2006,38(3):430-443
The proto-oncogene Pim-1 encodes a serine-threonine kinase which is a downstream effector of cytokine signaling and can enhance cell cycle progression by altering the activity of several cell cycle regulators among them the G1 specific inhibitor p21(Waf), the phosphatase Cdc25A and the kinase C-TAK1. Here, we demonstrate by using biochemical assays that Pim-1 can interact with the phosphatase Cdc25C and is able to directly phosphorylate the N-terminal region of the protein. Cdc25C is functionally related to Cdc25A but acts specifically at the G2/M cell cycle transition point and can be inactivated by C-TAK1-mediated phosphorylation. Immuno-fluorescence experiments showed that Pim-1 and Cdc25C co-localize in the cytoplasm of both epithelial and myeloid cells. We find that phosphorylation by Pim-1 enhances the phosphatase activity of Cdc25C and in transfected cells that are arrested in G2/M by bleomycin, Pim-1 can enhance progression into G1. Therefore, we propose that Pim-1 activates Cdc25C by a direct phosphorylation and can thereby assume the function of a positive cell cycle regulator at the G2/M transition. 相似文献
999.
1000.
Leone M Bechah Y Meghari S Lepidi H Capo C Raoult D Mege JL 《FEMS immunology and medical microbiology》2007,50(3):396-400
The objective of this study was to investigate the effects of age on infection with Coxiella burnetii, the agent of Q fever. Bacterial burden and granuloma number were increased in the spleens of 14-month-old as compared with 1-month-old mice. This increase was not the result of an anti-inflammatory macrophage response, because inflammatory and anti-inflammatory cytokines were induced in macrophages from young mice but were repressed in mature mice. In addition, macrophage microbicidal competence was similar in mature and young mice. These results suggest the importance of individual host factors in the pathophysiology of an infectious disease such as Q fever. 相似文献