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151.
The aim of the study was to assess the effect of basic technical-tactical elements, i.e. specific motor abilities, on performance in beach volleyball, with special reference to differences between the old and new official rules. Analysis of variance for 6 variables of technical-tactical elements between the winning and defeated teams included a sample of 129 sets played according to the old official rules (1995 and 1996) and 74 sets played according to the new official rules (2003). This was followed by regression analysis between these technical-tactical elements as predictors and a variable, i.e. score difference at which the team won or lost the game, as a criterion. Results of the analysis of variance between the winning and defeated teams showed highest differences in the performance of attack-hit, followed by counterattack-hit and blocking in both game types. However, difference in the performance of serve reception, serve, and field defense between the winning and defeated teams decreased significantly with the use of new rules as compared with the old ones. Results of regression analysis indicated the sets played according to the new rules relative to old ones to increase the predominant impact of technical-tactical elements in the above-net actions, especially attack-hit and block, on the final result in beach volleyball. 相似文献
152.
The aim of the study was to identify the morphological structures that determine achievement of top results in karate. The study included a sample of 85 karateka competing as senior category athletes within the Croatian Karate Society, aged 18-29 years. Sixteen morphological parameters were used; technical efficiency was assessed using 8 variables, i.e. evaluation of particular karate techniques, whereas fighting efficiency was estimated on the basis of results achieved at a number of contests. Factorial analysis of morphological space revealed the presence of four major factors: factor of muscle mass, followed by skeleton transverse dimensionality, factor of skeleton longitudinal dimensionality, factor of subcutaneous adipose tissue, and factor of shoulder width determining optimal trunk proportions (athlete type) in karateka. Regression analysis showed the isolated group of morphological factors to significantly determine both technical and fighting efficiency of karate athletes. Generally, skeleton longitudinality and muscle mass, followed by skeleton transverse dimensionality were found to exert favorable effects, and adipose tissue unfavorable effects according to both criteria. Also, each individual morphological factor influenced the performance of every karate technique applied. Adipose tissue had greatest unfavorable impact, whereas shoulder width and muscle mass had favorable impact on the performance of arm techniques (kicking). Considering performance of leg techniques, skeleton longitudinality had highest favorable impact, and adipose tissue greatest unfavorable impact. Of the techniques applied, combined karate kicks, i.e. jaku zuki-mawashi geri and kizame zuki-jaku zuki were found to be the best predictors of fighting efficiency. 相似文献
153.
Tahereh Jafari Aino-Liisa Alanne Jouni Issakainen Kati Pihlaja Jari Sinkkonen 《Fungal biology》2018,122(2-3):138-146
Herbarium specimens are a treasure trove for biochemical studies. However, this implies understanding of the chemical changes during the drying and storage of the specimen. We compared herbarium specimens at different ages and fresh samples of four mushroom species (Kuehneromyces mutabilis, Hypholoma capnoides, Kuehneromyces lignicola, Hypholoma fasciculare) of two genera in the family Strophariaceae by using proton nuclear magnetic resonance (1H NMR) spectroscopy combined with principal component analysis (PCA). 25 metabolites were identified. No significant alterations were found between herbarium samples at different ages, suggesting that they are stable enough for comparative studies. The most dominant differences between fresh and herbarium samples was that sugars such as α-α-trehalose, and fumaric and malic acids were more abundant in fresh fungi. Total contents of fatty and amino acids, uracil and γ-aminobutyric acid (GABA) were higher in herbarium specimens. In addition, pyroglutamic acid was observed only in Kuehneromyces mutabilis and fasciculic acid E in Hypholomafasciculare. Hence, based on results of the studied taxa, we conclude that NMR metabolomics can be used for both fresh and dried mushrooms when such alterations are properly addressed. 相似文献
154.
Ilari Pulli Muhammad Yasir Asghar Kati Kemppainen Kid Törnquist 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(11):1668-1677
Metabolites of sphingomyelin, as well as calcium ion fluxes, have a profound role in cellular signaling in almost all cell types. In addition, metabolites of sphingomyelin often modulate calcium signaling, either directly or indirectly. This is an interesting aspect on how lipids may wield their physiological role, as calcium is probably one of the most versatile signaling molecules in the cell, and as modulation of calcium signaling has profound effects on cellular physiology. The aim of this review is to discuss the mechanisms by which metabolites of sphingomyelin, especially the sphingolipids sphingosine and sphingosine 1-phosphate (S1P), modulate calcium fluxes, and how this may affect cellular function. In addition, the pathological aspects of sphingolipid-evoked modulation of calcium fluxes will be discussed. 相似文献
155.
Design,synthesis, and neuraminidase inhibitory activity of GS-4071 analogues that utilize a novel hydrophobic paradigm 总被引:1,自引:0,他引:1
Hanessian S Wang J Montgomery D Stoll V Stewart KD Kati W Maring C Kempf D Hutchins C Laver WG 《Bioorganic & medicinal chemistry letters》2002,12(23):3425-3429
Structure-based design has led to the synthesis of a novel analogue of GS-4071, an influenza neuraminidase inhibitor, in which the basic amino group has been replaced by a hydrophobic vinyl group. An X-ray co-crystal structure of the new inhibitor (K(i)=45 nM) bound to the active site shows that the vinyl group occupies the same subsite as the amino group in GS-4071. 相似文献
156.
157.
Ralph Stuttmann Jens Jakubetz Kati Schultz Claudia Schäfer Sebastian Langer Utz Ullmann Peter Hilbert 《BMC anesthesiology》2010,10(1):1-11
Background
Org 25435 is a new water-soluble alpha-amino acid ester intravenous anaesthetic which proved satisfactory in animal studies. This study aimed to assess the safety, tolerability and efficacy of Org 25435 and to obtain preliminary pharmacodynamic and pharmacokinetic data.Methods
In the Short Infusion study 8 healthy male volunteers received a 1 minute infusion of 0.25, 0.5, 1.0, or 2.0 mg/kg (n = 2 per group); a further 10 received 3.0 mg/kg (n = 5) or 4.0 mg/kg (n = 5). Following preliminary pharmacokinetic modelling 7 subjects received a titrated 30 minute Target Controlled Infusion (TCI), total dose 5.8-20 mg/kg.Results
Within the Short Infusion study, all subjects were successfully anaesthetised at 3 and 4 mg/kg. Within the TCI study 5 subjects were anaesthetised and 2 showed signs of sedation. Org 25435 caused hypotension and tachycardia at doses over 2 mg/kg. Recovery from anaesthesia after a 30 min administration of Org 25435 was slow (13.7 min). Pharmacokinetic modelling suggests that the context sensitive half-time of Org 25435 is slightly shorter than that of propofol in infusions up to 20 minutes but progressively longer thereafter.Conclusions
Org 25435 is an effective intravenous anaesthetic in man at doses of 3 and 4 mg/kg given over 1 minute. Longer infusions can maintain anaesthesia but recovery is slow. Hypotension and tachycardia during anaesthesia and slow recovery of consciousness after cessation of drug administration suggest this compound has no advantages over currently available intravenous anaesthetics. 相似文献158.
The aim of the study was to identify motor structures in elite female volleyball players aged 14-17, and to assess the effect of these motor structures on their technical and situation efficiency. For this purpose, a battery of 12 motor tests as predictor variables, and a set of six technical elements and evaluation of performance quality as criterion variables were applied in a sample of 147 female volleyballers aged 14-15 and a sample of 50 female volleyballers aged 16-17. Analysis of variance between subgroups within the groups of volleyballers aged 14-15 and those aged 16-17 showed the results on all motor tests to improve with the increase in situation performance, which was especially pronounced in the tests assessing explosive strength and agility. The same held true for the results on all tests assessing volleyball techniques, spike and block in particular. In both samples, factor analysis of motor tests isolated two factors underlain by the generation and regulation of strength, and the mechanism of speed regulation. Canonical correlation analysis between the motor regulatory mechanisms and technical elements revealed determination of the mechanisms of strength and technical efficiency in both samples. Regression correlation analysis showed the mechanisms of strength regulation and speed to be good predictors of game performance in female volleyballers aged 14-15 and 16-17, whereby the mechanism of strength regulation had greater effect on the game performance than the mechanism of speed regulation. Regression correlation analysis also revealed the set of 6 techniques evaluated to be a good predictor of situation efficiency in both groups of female volleyballers aged 14-15 and 16-17. The block and spike techniques were found to be the best predictors of game performance quality in the former, and the techniques of spike and block in the latter. Based on the results obtained, a possible model of selection for supreme score achievement in female volleyball is described. 相似文献
159.
160.
Pramod Sukumaran Christoffer L?f Kati Kemppainen Pasi Kankaanp?? Ilari Pulli Johnny N?sman Tero Viitanen Kid T?rnquist 《The Journal of biological chemistry》2012,287(53):44345-44360
Mammalian non-selective transient receptor potential cation channels (TRPCs) are important in the regulation of cellular calcium homeostasis. In thyroid cells, including rat thyroid FRTL-5 cells, calcium regulates a multitude of processes. RT-PCR screening of FRTL-5 cells revealed the presence of TRPC2 channels only. Knockdown of TRPC2 using shRNA (shTRPC2) resulted in decreased ATP-evoked calcium peak amplitude and inward current. In calcium-free buffer, there was no difference in the ATP-evoked calcium peak amplitude between control cells and shTRPC2 cells. Store-operated calcium entry was indistinguishable between the two cell lines. Basal calcium entry was enhanced in shTRPC2 cells, whereas the level of PKCβ1 and PKCδ, the activity of sarco/endoplasmic reticulum Ca2+-ATPase, and the calcium content in the endoplasmic reticulum were decreased. Stromal interaction molecule (STIM) 2, but not STIM1, was arranged in puncta in resting shTRPC2 cells but not in control cells. Phosphorylation site Orai1 S27A/S30A mutant and non-functional Orai1 R91W attenuated basal calcium entry in shTRPC2 cells. Knockdown of PKCδ with siRNA increased STIM2 punctum formation and enhanced basal calcium entry but decreased sarco/endoplasmic reticulum Ca2+-ATPase activity in wild-type cells. Transfection of a truncated, non-conducting mutant of TRPC2 evoked similar results. Thus, TRPC2 functions as a major regulator of calcium homeostasis in rat thyroid cells. 相似文献