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21.
PR Marcelino MS Aoki AFS Arruda CG Freitas A Mendez-Villanueva A Moreira 《Biology of sport / Institute of Sport》2016,33(1):37-42
The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size. 相似文献
22.
MS Y?ld?r?m S Ozyurek O? Tosun S Uzer N Gelecek 《Biology of sport / Institute of Sport》2016,33(1):89-94
The aim of this study was to compare the effects of static stretching, proprioceptive neuromuscular facilitation (PNF) stretching and Mulligan technique on hip flexion range of motion (ROM) in subjects with bilateral hamstring tightness. A total of 40 students (mean age: 21.5±1.3 years, mean body height: 172.8±8.2 cm, mean body mass index: 21.9±3.0 kg · m-2) with bilateral hamstring tightness were enrolled in this randomized trial, of whom 26 completed the study. Subjects were divided into 4 groups performing (I) typical static stretching, (II) PNF stretching, (III) Mulligan traction straight leg raise (TSLR) technique, (IV) no intervention. Hip flexion ROM was measured using a digital goniometer with the passive straight leg raise test before and after 4 weeks by two physiotherapists blinded to the groups. 52 extremities of 26 subjects were analyzed. Hip flexion ROM increased in all three intervention groups (p<0.05) but not in the no-intervention group after 4 weeks. A statistically significant change in initial–final assessment differences of hip flexion ROM was found between groups (p<0.001) in favour of PNF stretching and Mulligan TSLR technique in comparison to typical static stretching (p=0.016 and p=0.02, respectively). No significant difference was found between Mulligan TSLR technique and PNF stretching (p=0.920). The initial–final assessment difference of hip flexion ROM was similar in typical static stretching and no intervention (p=0.491). A 4-week stretching intervention is beneficial for increasing hip flexion ROM in bilateral hamstring tightness. However, PNF stretching and Mulligan TSLR technique are superior to typical static stretching. These two interventions can be alternatively used for stretching in hamstring tightness. 相似文献
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24.
Aim: To determine if there is an association between the Chlamydia and Mycoplasma infections with socio-demographic and clinical factors, and also with infertility. Methods: We conducted a study on 100 infertile married women and 100 control group, and collected data on the socio-demographic, hormonal and tubo-ovarian factors. The results of the endocervical swabs were analyzed for Mycoplasma and Chlamydia infection, the bacterial counts were also determined. Results: The percentage positivity to infection was significantly more among the infertile group compared to the control group, and also significantly more among the age group <30 years old. The positivity for infection with Chlamydia and/or Mycoplasma was significantly correlated with age, history of irregular menstruation, and history of previous abortion. Further sub-analysis of the infertile group showed that positivity to Chlamydia and/or Mycoplasma infection was significantly correlated to hormonal factors, ovarian factors, irregular menstruation, and previous abortion. Regression analysis showed that hormonal, ovarian factors, and irregular menstruation were the most significant factors in the positivity to Chlamydia and Mycoplasma infection. Bacterial count was significantly correlated with age, history of irregular menstruation, and history of previous abortion. Conclusion: Infection to Chlamydia and Mycoplasma is associated to younger age (?30 years old), and occurs in the infertile women. There is an interplay between infection in younger women, irregular menstruation, hormonal, and tubo-ovarian factors with infertility. Bacterial count was significantly correlated with age, history of irregular menstruation, and history of previous abortion. 相似文献
25.
Yu Du PhD Jing Li MS Yuluan Hou MS Chanchan Chen PhD Weilin Long MS Hongwei Jiang PhD 《Journal of cellular biochemistry》2019,120(8):i-i
Circular RNAs (circRNAs) are novel noncoding RNAs and play crucial roles in various biological processes. However, little is known about the functions of circRNAs in osteogenic differentiation. The current study aimed to investigate the differential expression of circRNAs in rat dental follicle cells (rDFCs) during osteogenic differentiation, identified by RNA high-throughput sequencing and quantitative real-time polymerase chain reaction. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to further explore the biofunctions of circRNA biofunctions. Two hundred sixty-six differentially-expressed circRNAs that are involved in several important signaling pathways, including mitogen-activated protein kinases (MAPK) and transforming growth factor-β (TGF-β) signaling pathways were revealed. Among these, circFgfr2 and its predicted downstream targets, miR-133 and BMP6 (bone morphogenetic protein-6), were identified both in vivo and in vitro. For further validation, circFgfr2 was overexpressed in rDFCs, the results showed that the expression of miR-133 was downregulated and the expression of BMP6 was upregulated. Taken together, the results revealed the circRNA expression profiles and indicated the importance of circRNAs of rDFCs. In addition, circFgfr2 might promote osteogenesis by controlling miR-133/BMP6, which is a potential new target for the manipulation of tooth regeneration and bone formation. 相似文献
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27.
Mitsuomi?Shimazakimitujin@fish.hokudai.ac.jp; MY myabe@fish.hokudai.ac.jp" title="MS mitujin@fish.hokudai.ac.jp; MY myabe@fish.hokudai.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Hiromitsu?Endo Mamoru?Yabe 《Ichthyological Research》2004,51(2):120-125
Halieutopsis bathyoreos Bradbury, 1988 (Lophiiformes: Ogcocephalidae), previously described only on the basis of the holotype (62.6mm in standard length) from the central North Pacific, is redescribed on the basis of the holotype and six additional specimens (41.2–68.7mm in standard length) collected from the western South Pacific, off Papua New Guinea, and the western North Pacific, including the Japanese Archipelago. Halieutopsis bathyoreos is distinguished from its congeners by having a shelflike rostrum extending anteriorly well beyond the mouth, a dorsal escal lobe slightly bisected ventrally, an illicial cavity square in outline and completely visible in ventral view, and lacking tubercles on the ventral surface of the disk. The following characters are newly added to the diagnoses of this species: rostrum width 21–29% of head length, tubercles on the dorsal surface of the disk about half the diameter of those on the lateral margin, and 13–15 large lateral-line scales on the tail. 相似文献
28.
The purpose of this research was to improve the solubility and therefore dissolution and bioavailability of triamterene, a
poorly water soluble diuretic, by complexation with β-cyclodextrin. Triamterene has been reported to show low bioavailability
after oral administration, with wide intersubject variation. This study presents the formulation of solid dispersions of triamterene
with β-cyclodextrin—by cogrinding, kneading, and coevaporation, using low pH conditions—and their characterizations, evaluation
of improvement in dissolution profiles, and in vivo advantage. Phase solubility studies indicated complex with possible stoichiometry
of 1∶1 and a stability constant of 167.67M−1. The solid dispersions were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, x-ray diffraction,
and differential scanning calorimetry studies. The characterization studies confirmed inclusion of the phenyl ring of triamterene
within the nonpolar cavity of β-cyclodextrin in the coevaporate. Remarkable improvement in in vitro drug release profiles
in 0.1 N HCl and pH 6.8 phosphate buffer was observed with all dispersions, especially the coevaporate. The coevaporate, when
administered orally in rats, also exhibited improved in vivo activity, as measured by net sodium ion excretion, as compared
with triamterene powder. Thus, coevaporation of the drug and β-cyclodextrin from acidified alcohol provide the optimum condition
for inclusion complexation to give a binary system with remarkable improvement in in vitro drug release profile and in vivo
performance. 相似文献
29.
The hypothesis that cardiac rhythms are associated with chaotic dynamics implicating a healthy flexibility has motivated
the investigation of continuous ECG with methods of nonlinear system theory. Sleep is known to be associated with modulations
of the sympathetic and parasympathetic control of cardiac dynamics. Thus, the differentiation of ECG signals recorded during
different sleep stages can serve to determine the usefulness of nonlinear measures in discriminating ECG states in general.
For this purpose the following six nonlinear measures were implemented: correlation dimension D2, Lyapunov exponent L1. Kolmogorov
entropy K2, as well as three measures derived from the analysis of unstable periodic orbits. Results of this study show that
continuous ECG signals can be differentiated from linear stochastic surrogates by each of the nonlinear measures. The most
significant finding with respect to the sleep-related differentiation of ECG signals is an increase in dominant chaoticity
assessed by L1 and a reduction in the degrees of freedom estimated by D2 during REM sleep compared to slow wave sleep. Our
findings suggest that the increase in dominant chaoticity during REM sleep with regard to time-continuous nonlinear analysis
is comparable to an increased heart rate variability. The reduction in the correlation dimension may be interpreted as an
expression of the withdrawal of respiratory influences during REM sleep.
Received: 7 June 1999 / Accepted in revised form: 10 December 1999 相似文献
30.
In recent years evidence has accumulated that ECG signals are of a nonlinear nature. It has been recognized that strictly
periodic cardiac rhythms are not accompanied by healthy conditions but, on the contrary, by pathological states. Therefore,
the application of methods from nonlinear system theory for the analysis of ECG signals has gained increasing interest. Crucial
for the application of nonlinear methods is the reconstruction (embedding) of the time series in a phase space with appropriate
dimension. In this study continuous ECG signals of 12 healthy subjects recorded during different sleep stages were analysed.
Proper embedding dimension was determined by application of two techniques – the false nearest neighbours method and the saturation
of the correlation dimension. Results for the ECG signals were compared with findings for simulated data (quasiperiodic dynamics,
Lorenz data, white noise) and for phase randomized surrogates. Findings obtained with the two approaches suggest that embedding
dimensions from 6 to 8 may be regarded as suitable for the topologically proper reconstruction of ECG signals.
Received: 7 June 1999 / Accepted in revised form: 10 December 1999 相似文献