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261.
This study aimed to compare the effects of different velocities of eccentric muscle actions on acute blood lactate and serum growth hormone (GH) concentrations following free weight bench press exercises performed by resistance-trained men. Sixteen healthy men were divided into two groups: slow eccentric velocity (SEV; n = 8) and fast eccentric velocity (FEV; n = 8). Both groups performed four sets of eight eccentric repetitions at an intensity of 70% of their one repetition maximum eccentric (1RMecc) test, with 2-minute rest intervals between sets. The eccentric velocity was controlled to 3 seconds per range of motion for SEV and 0.5 seconds for the FEV group. There was a significant difference (P < 0.001) in the kinetics of blood lactate removal (at 3, 6, 9, 15, and 20 min) and higher mean values for peak blood lactate (P = 0.001) for the SEV group (9.1 ± 0.5 mM) compared to the FEV group (6.1 ± 0.4 mM). Additionally, serum GH concentrations were significantly higher (P < 0.001) at 15 minutes after bench press exercise in the SEV group (1.7 ± 0.6 ng · mL−1) relative to the FEV group (0.1 ± 0.0 ng · mL−1). In conclusion, the velocity of eccentric muscle action influences acute responses following bench press exercises performed by resistance-trained men using a slow velocity resulting in a greater metabolic stress and hormone response.  相似文献   
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Convolvulus boissieri is an edaphic endemic plant which grows in the Baetic ranges always in association with high mountain xeric dolomitic outcrops. As these dolomitic areas appear in a ‘soil‐island’ pattern, the distribution of this species is disjunct. Populations of this species frequently include a low number of individuals, which could have an important impact on their genetic diversity and viability. Convolvulus boissieri provides an excellent opportunity to study the genetic and phylogeographical aspects of species linked to dolomites. We used amplified fragment length polymorphism markers and nuclear (internal transcribed spacer region of the nuclear ribosomal cistron) and plastid sequences (trnL‐trnF, rpl32‐trnL and trnQ‐5′rps16). Data were generated from 15 populations, representing the distribution area of the species. For sequence analysis and estimation of divergence times we also used sequences from other Convolvulus species. Results revealed low intrapopulational genetic diversity and a strong interpopulational structure. Furthermore, we found clear‐cut differentiation caused by the existence of two large population groups separated by the Guadiana Menor river basin. Estimation of divergence times indicated that divergence took place during the Pleistocene glaciations. Genetic diversity and differentiation are similar to those other species exhibiting naturally fragmented distribution with a sky islands pattern. In phylogeographical terms, the successive glaciation–interglaciation cycles caused the species to spread from the western sites to eastern sites, the latter being more exposed to the effects of glaciation. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 506–523.  相似文献   
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Plant Molecular Biology Reporter - Nitrogen-fixing bacteria establish symbiosis with legumes for the biological nitrogen fixation process in specific root structures called nodules. Among these...  相似文献   
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In order to accommodate a newly discovered fossil specimen related to a subset of extant needle stoneflies (Leuctridae sensu Zwick, 2000), we provide a comparative analysis of the wing venation of these insects, and of their close relatives, primarily based on extant material. A number of character states potentially supporting monophyletic taxa are identified, and are used to erect taxon names under the cladotypic nomenclatural procedure. We introduce a new standard definition in which the mention of the antonym of the defining character state is applied. The proposed taxa, and taxa inclusiveness, are as follows: Nemouromorpha > Capniida/Leuctrida/‘Nemouridae s.l.’, and Leuctrida > Exeleuctrida > Mioleuctrida & Eleuctrida > Collaleuctrida. This scheme allowed us to tentatively accommodate several fossil species described earlier and the new specimen, left undetermined at the genus and species levels, but assigned to Collaleuctrida. To optimize retrieval of hierarchical information, we introduce the use of ‘nec’ (Latin for ‘but not’) into the taxonomic address to indicate exclusion from a taxon. For example, Mioleuctrida nec Collaleuctrida ?yehae indicates that ?yehae can be assigned to Mioleuctrida but can also be conclusively excluded from Collaleuctrida. Based on the investigated case, it is finally argued that the cladotypic nomenclatural procedure is optimal regarding name use and numbers, and allows adequate treatment of homoplasy.  相似文献   
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Background  

Spontaneous intracerebral hemorrhage (ICH) accounts for a high mortality and morbidity. Early prediction of outcome is crucial for optimized care and treatment decision. Copeptin, the C-terminal part of provasopressin, has emerged as a new prognostic marker in a variety of diseases, but its prognostic value in ICH is unknown.  相似文献   
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Many studies, concerning cardiovascular reactivity in hypertensives, show contrasting data. The aim of the present study was to check, also measuring extracardiovascular variables, a procedure able to identify a peculiar characteristic of the prehypertensive phase. We studied 47 normotensives, who referred high blood pressure values, but that we did not find in our visit. The cardioneurovascular assessment was evaluated, by means of a non invasive, beat to beat technique, measuring SBP, DBP, HR, muscular contraction and skin conductance level (EMG, SCL), peripheric temperature (PT), during a psychophysiologic session. This was composed by 4 stressors (mental arithmetic and Sacks test, acoustic and electric stimulations), 5 minutes each, preceded and followed by an observation period of 10 minutes. After 18 month follow-up, we could distinguish 26 hypertensives (H), and 21 subjects maintained normal blood pressure values (N). The obtained findings showed, with statistical significance, 1) the hyperresponsiveness of SCL and PT; 2) the failed recovery, with consequent hyperdysreactivity, of SCL and PT; 3) the presence of both these phenomena in the H., while SBP, DBP and HR responses did not result a discriminative tool. These data seem 1) to reinforce the hypothesis that a hypersympathetic phase can characterize the prehypertensive stages of essential hypertension and 2) to suggest the psychophysiological approach as a useful method to diagnose prehypertension.  相似文献   
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