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91.
D Deprez J Fransen M Lenoir RM Philippaerts R Vaeyens 《Biology of sport / Institute of Sport》2015,32(1):65-70
The aim of the study was to investigate test reliability of the Yo-Yo intermittent recovery test level 1 (YYIR1) in 36 high-level youth soccer players, aged between 13 and 18 years. Players were divided into three age groups (U15, U17 and U19) and completed three YYIR1 in three consecutive weeks. Pairwise comparisons were used to investigate test reliability (for distances and heart rate responses) using technical error (TE), coefficient of variation (CV), intra-class correlation (ICC) and limits of agreement (LOA) with Bland-Altman plots. The mean YYIR1 distances for the U15, U17 and U19 groups were 2024 ± 470 m, 2404 ± 347 m and 2547 ± 337 m, respectively. The results revealed that the TEs varied between 74 and 172 m, CVs between 3.0 and 7.5%, and ICCs between 0.87 and 0.95 across all age groups for the YYIR1 distance. For heart rate responses, the TEs varied between 1 and 6 bpm, CVs between 0.7 and 4.8%, and ICCs between 0.73 and 0.97. The small ratio LOA revealed that any two YYIR1 performances in one week will not differ by more than 9 to 28% due to measurement error. In summary, the YYIR1 performance and the physiological responses have proven to be highly reliable in a sample of Belgian high-level youth soccer players, aged between 13 and 18 years. The demonstrated high level of intermittent endurance capacity in all age groups may be used for comparison of other prospective young soccer players. 相似文献
92.
Andy?Pang Andrew?D?Smith Paulo?AS?Nuin Elisabeth?RM?TillierEmail author 《BMC bioinformatics》2005,6(1):236
Background
General protein evolution models help determine the baseline expectations for the evolution of sequences, and they have been extensively useful in sequence analysis and for the computer simulation of artificial sequence data sets. 相似文献93.
Developmental and wound-, cold-, desiccation-, ultraviolet-B-stress-induced modulations in the expression of the petunia zinc finger transcription factor gene ZPT2-2 下载免费PDF全文
van Der Krol AR van Poecke RM Vorst OF Voogt C van Leeuwen W Borst-Vrensen TW Takatsuji H van Der Plas LH 《Plant physiology》1999,121(4):1153-1162
The ZPT2-2 gene belongs to the EPF gene family in petunia (Petunia hybrida), which encodes proteins with TFIIIA-type zinc-finger DNA-binding motifs. To elucidate a possible function for ZPT2-2, we analyzed its pattern of expression in relation to different developmental and physiological stress signals. The activity of the ZPT2-2 promoter was analyzed using a firefly luciferase (LUC) reporter gene, allowing for continuous measurements of transgene activity in planta. We show that ZPT2-2::LUC is active in all plant tissues, but is strongly modulated in cotyledons upon germination, in leaves in response to desiccation, cold treatment, wounding, or ultraviolet-B light, and in petal tissue in response to pollination of the stigma. Analysis of mRNA levels indicated that the modulations in ZPT2-2::LUC expression reflect modulations in endogenous ZPT2-2 gene expression. The change in ZPT2-2::LUC activity by cold treatment, wounding, desiccation, and ultraviolet-B light suggest that the phytohormones ethylene and jasmonic acid are involved in regulating the expression of ZPT2-2. Although up-regulation of expression of ZPT2-2 can be blocked by inhibitors of ethylene perception, expression in plants is not induced by exogenously applied ethylene. The application of jasmonic acid does result in an up-regulation of gene activity and, thus, ZPT2-2 may play a role in the realization of the jasmonic acid hormonal responses in petunia. 相似文献
94.
Kjellman BM Fredrikson M Glad-Mattsson G Sjöberg F Huss FR 《Annals of surgical innovation and research》2011,5(1):4-8
Background
Hypothermia in burns is common and increases morbidity and mortality. Several methods are available to reach and maintain normal core body temperature, but have not yet been evaluated in critical care for burned patients. Our unit's ordinary technique for controlling body temperature (Bair Hugger®+ radiator ceiling + bed warmer + Hotline®) has many drawbacks e.g.; slow and the working environment is hampered. The aim of this study was to compare our ordinary heating technique with newly-developed methods: the Allon?2001 Thermowrap (a temperature regulating water-mattress), and Warmcloud (a temperature regulating air-mattress).Methods
Ten consecutive burned patients (> 20% total burned surface area and a core temperature < 36.0°C) were included in this prospective, randomised, comparative study. Patients were randomly exposed to 3 heating methods. Each treatment/measuring-cycle lasted for 6 hours. Each heating method was assessed for 2 hours according to a randomised timetable. Core temperature was measured using an indwelling (bladder) thermistor. Paired t-tests were used to assess the significance of differences between the treatments within the patients. ANOVA was used to assess the differences in temperature from the first to the last measurement among all treatments. Three-way ANOVA with the Tukey HSD post hoc test and a repeated measures ANOVA was used in the same manner, but included information about patients and treatment/measuring-cycles to control for potential confounding. Data are presented as mean (SD) and (range). Probabilities of less than 0.05 were accepted as significant.Results
The mean increase, 1.4 (SD 0.6°C; range 0.6-2.6°C) in core temperature/treatment/measuring-cycle highly significantly favoured the Allon?2001 Thermowrap in contrast to the conventional method 0.2 (0.6)°C (range -1.2 to 1.5°C) and the Warmcloud 0.3 (0.4)°C (range -0.4 to 0.9°C). The procedures for using the Allon?2001 Thermowrap were experienced to be more comfortable and straightforward than the conventional method or the Warmcloud.Conclusions
The Allon?2001 Thermowrap was more effective than the Warmcloud or the conventional method in controlling patients' temperatures. 相似文献95.
96.
Responses of acutely isolated neurons from the rostral nucleus of the
solitary tract (rNST) to GABA receptor agonists and antagonists were
investigated using whole-cell recording in current clamp mode. The isolated
neurons retain their morphology and can be divided into multipolar,
elongate and ovoid cell types. Most rNST neurons (97%), including all three
cell types, respond to GABA with membrane hyperpolarization and a reduction
in input resistance. The GABA(A) receptor agonist muscimol reduces neuronal
input resistance in a concentration-dependent manner, whereas the GABA(B)
receptor agonist baclofen had no effect on any of the neurons tested. The
GABA and muscimol reversal potentials were both found to be -75 mV Both the
GABA competitive antagonist picrotoxin and the GABA(A) receptor antagonist
bicuculline block the effect of GABA in a concentration-dependent manner.
These results suggest that GABA activates all neurons in the rNST and that
inhibitory synaptic activity is important in brainstem processing of
gustatory and somatosensory information.
相似文献
97.
Replacement of receptor cells in the hamster vomeronasal epithelium after nerve transection 总被引:1,自引:1,他引:0
Chemoreceptor cells in the vomeronasal and olfactory epithelium are
replaced following experimentally induced degeneration. This study analyzes
quantitatively the time course and degree of vomeronasal receptor cell
replacement. Unilateral transection of the vomeronasal nerves in adult
hamster was used to induce a retrograde degeneration of receptor cells in
the vomeronasal organ. Histological measurement of both number of receptor
cells and epithelial thickness were made for recovery times from 0 to 60
days. After nerve transection, there was a gradual degeneration of receptor
cells, the number decreasing to 50% of control by day 2 and 16% by day 6.
During days 7-15 maximum receptor cell replacement was observed. Cell
number increased rapidly and reached a peak on day 15. At recovery times of
40-60 days, cell number returned to the control level. Epithelial
thickness, however, decreased to 60-70% during the degeneration period
(days 4-6) and did not return to control levels. After 40-60 days
epithelial thickness remained at 70% of control. These results demonstrate
that vomeronasal receptor cells are replaced following degeneration, but
epithelial thickness does not return to control levels. These findings
suggest that the number of replacement cells is not limited by the reduced
thickness of the epithelium, and that recovery mechanisms may function to
restore an optimum number of receptor cells.
相似文献
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99.
The B domain of CGTase has been generally accepted as a domain involved in thermostability. However, limited work has been performed in which entire B domain is substituted with the thermostable counterpart. Using overlap extension PCR, we replaced the B domain of a variant of CGTase Bacillus sp. G1 by six other B domains from thermostable CGTases. Likely due to distortion in the substrate-binding cleft adjacent to the active site, variants with the domain replacements from Thermoanaerobacter, Thermococcus, Thermococcus kodakarensis, Anaerobranca gottschalkii and Pyrococcus furiosus completely lost their catalytic function. A mutant designated Cgt_ET1 with a domain replacement from a Bacillus stearopthermophilus ET1 CGTase was the only variant that retained activity after domain exchange. Both the parental enzyme and the mutant Cgt_ET1 had an identical optimum temperature at 60 °C. The activity half-life was 22 min for the parental CGTase, whereas a marked increase to 57 min was observed for the mutant. Further mutagenesis on Cgt_ET1 was performed at residue 188 by replacing a Phe residue with Tyr. The mutant Cgt_ET1_F188Y displayed a decreased activity half-life of 28 min. Both mutants exhibited a better cyclodextrin-forming ability and a faster turnover rate (kcat) than the parental CGTase. 相似文献
100.