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41.
The occurrence frequencies of the dinucleotides of genes of three thermophilic and three mesophilic species from both archaea
and eubacteria were investigated in this study. The genes encoding water soluble proteins were rich in the dinucleotides of
purine dimers, whereas the genes encoding membrane proteins were rich in pyrimidine dimers. The dinucleotides of purine dimers
are the counterparts of pyrimidine dimers in a double-stranded DNA. The purine/pyrimidine dimers were favored in the thermophiles
but not in the mesophiles, based on comparisons of observed and expected frequencies. This finding is in agreement with our
previous study which showed that purine/pyrimidine dimers are positive factors that increase the thermal stability of DNA.
The dinucleotides AA, AG, and GA are components of the codons of charged residues of Glu, Asp, Lys, and Arg, and the dinucleotides
TT, CT, and TC are components of the codons of hydrophobic residues of Leu, Ile, and Phe. This is consistent with the suitabilities
of the different amino acid residues for water soluble and membrane proteins. Our analysis provides a picture of how thermophilic
species produce water soluble and membrane proteins with distinctive characters: the genes encoding water soluble proteins
use DNA sequences rich in purine dimers, and the genes encoding membrane proteins use DNA sequences rich in pyrimidine dimers
on the opposite strand. 相似文献
42.
Kawano H Iemitsu M Gando Y Ishijima T Asaka M Aoyama T Ando T Tokizawa K Miyachi M Sakamoto S Higuchi M 《Journal of sports sciences》2012,30(3):241-246
The present study elucidated the effects of habitual rowing exercise on arterial stiffness and plasma levels of the vasoconstrictor endothelin-1 and the vasodilator nitric oxide (NO) in older men. Eleven rowers (68.0 ± 1.6 years) and 11 sedentary control older men (64.9 ± 1.1 years) were studied. Peak oxygen uptake (36.0 ± 1.7 vs. 27.7 ±1.9 ml · kg(-1) · min(-1)), leg press power (1346 ± 99 vs. 1077 ± 68 W), and HDL-cholesterol (75 ± 5 vs. 58 ±3 mg · ml(-1)) were higher and triglyceride (78 ± 9 vs. 120 ± 14 mg · ml(-1)) was lower in rowers than in control participants (all P < 0.05). Arterial stiffness indices (carotid β-stiffness and cardio-ankle vascular index) and plasma endothelin-1 and NOx (nitrite + nitrate) levels did not differ between the two groups. These results suggest that habitual rowing exercise in older men is associated with high muscle power and aerobic capacity, and favourable blood lipid profile without affecting arterial stiffness or plasma levels of endotheline-1 and NO. 相似文献
43.
Iida H Kato S Sekino Y Sakai E Uchiyama T Endo H Hosono K Sakamoto Y Fujita K Yoneda M Koide T Takahashi H Tokoro C Goto A Abe Y Kobayashi N Kubota K Gotoh E Maeda S Nakajima A Inamori M 《Journal of Zhejiang University. Science. B》2012,13(1):29-34
Objective
The ideal medication for the treatment of acid-related diseases, e.g., peptic ulcers, stress-related gastric bleeding, functional dyspepsia, and gastroesophageal reflux disease, should have a rapid onset of action to promote hemostasis and relieve the symptoms. The aim of our study was to investigate the inhibitory effects on gastric acid secretion of a single oral administration of a proton pump inhibitor, omeprazole 20 mg, and an H2-receptor antagonist, roxatidine 75 mg.Methods
Ten Helicobacter pylori-negative male subjects participated in this randomized, two-way crossover study. Intragastric pH was monitored continuously for 6 h after single oral administration of omeprazole 20 mg and roxatidine 75 mg. Each administration was separated by a 7-d washout period.Results
During the 6-h study period, the average pH after administration of roxatidine was higher than that after administration of omeprazole (median: 4.45 vs. 2.65; P=0.0367). Also during the 6-h study period, a longer duration of maintenance at pH above 2, 5, and 6 was observed after administration of roxatidine 75 mg than after administration of omeprazole 20 mg (median: 90.6% vs. 55.2%, P=0.0284; 43.7% vs. 10.6%, P=0.0125; 40.3% vs. 3.3%, P=0.0125; respectively).Conclusions
In Helicobacter pylori-negative healthy male subjects, oral administration of roxatidine 75 mg increased the intragastric pH more rapidly than that of omeprazole 20 mg. 相似文献44.
Guided by theoretical models, this research examines (for the first time within the same design) young American adults' reports of age stereotypes, norms of respect, beliefs about intra‐ and intergenerational communication, and communication satisfaction toward young adult, middle‐aged, and older adult targets. Multivariate analyses showed that as age of target increased so did trait attributions of benevolence, norms of politeness and deference, and communicative respect and satisfaction; however, attributions of personal vitality decreased linearly. Path analyses revealed that the more young adults stereotyped older adults as benevolent and personally vital, the less likely they were to report avoiding communication with them. Deference norms also positively related to the degree of communicative respect afforded older adults and the more respondents reported avoiding communication with them, the less satisfied they were with their intergenerational conversations. 相似文献
45.
Hirofumi Shimojo Rio Nara Yasuhiro Baba Hiroshi Ichikawa Yusuke Ikeda Yoshimitsu Shimoyama 《Journal of sports sciences》2013,31(20):2339-2346
ABSTRACTAnkle flexibility is critical to obtain a high swimming velocity in undulatory underwater swimming (UUS). The present study investigated the Froude (propelling) efficiency and three-dimensional (3D) kinematics of human UUS following the extrinsic restriction of the ankle by tape application. In Experiment 1, swimmers (9 male and 8 female college swimmers) performed UUS trials involving normal swimming (Normal) and swimming with tape application at the ankle (Tape). Kicking frequency was controlled in both settings. UUS kinematics were obtained with a two-dimensional motion analysis. Swimming velocity significantly decreased during swimming with tape application compared with that during normal swimming (Normal, 1.33 m·s?1; Tape, 1.26 m·s?1, p < 0.05). The Froude efficiency was not affected (Normal, 0.77; Tape, 0.76), and ankle plantar angle did not decrease during swimming (Normal, 159.02°; Tape, 160.38°). In Experiment 2, lower limb rotations of a male swimmer were analysed using 3D motion analysis under the same conditions as Experiment 1. An insufficient forefoot rotation was observed during downstroke kicks (the phase of the highest acceleration to forward direction). These findings suggest that UUS velocity is affected by the mobility of end effector. 相似文献
46.
Hiroshi Kida 《Higher Education》1975,4(3):261-272
The present state of development of higher education is described and quantified. Notable characteristics of the system are (i) the predominance of private establishments, (ii) the variety of courses available, (iii) the wide social base from which students are drawn, (iv) the highly competitive nature of the entry procedures. The system faces many challenges including the linked problems of management and finance. 相似文献
47.
A 2 × 2 factorial experiment was conducted in a licking-suppression situation to test if a rat could count the number of shocks given in a 5-min session under signaled and unsignaled shock conditions. Groups F received three .7-sec grid shocks per session throughout 80 sessions, whereas Groups V received, on any day, one, two, three, four, or five shocks, with a mean of three shocks. The rats’ counting ability was assessed in terms of the post-third-shock acceleration of licking. The results of this measure were compared between Groups F and Groups V on test days in which both groups received three shocks with the identical shock sequence. There was no evidence that rats could count under either signaled or unsignaled shock conditions. The basal rate of licking was less in groups run under the unsignaled shock condition than under the signaled shock condition. The effect of fixed/variable shock frequency upon basal rate of licking was not significant. The results are discussed with reference to the optimal shock density view of Davis and Memmott (1982). 相似文献
48.
Marc H. Bornstein Catherine S. Tamis-LeMonda Joseph Tal Pamela Ludemann Sueko Toda Charles W. Rahn Marie-Germaine Pêcheux Hiroshi Azuma Danya Vardi 《Child development》1992,63(4):808-821
This study examines and compares prominent characteristics of maternal responsiveness to infant activity during home-based naturalistic interactions of mother-infant dyads in New York City, Paris, and Tokyo. Both culture-general and culture-specific patterns of responsiveness emerged. For example, in all 3 locales infants behaved similarly, mothers also behaved similarly with respect to a hierarchy of response types, and mothers and infants manifest both specificity and mutual appropriateness in their interactions: Mothers responded to infants' exploration of the environment with encouragement to the environment, to infants' vocalizing nondistress with imitation, and to infants' vocalizing distress with nurturance. Differences in maternal responsiveness among cultures occurred to infant looking rather than to infant vocalizing and in mothers' emphasizing dyadic versus extradyadic loci of interaction. Universals of maternal responsiveness, potential sources of cultural variation, and implications of similarities and differences in responsiveness for child development in different cultural contexts are discussed. 相似文献
49.
50.
Yusuke Ikeda Hiroshi Ichikawa Rio Nara Yasuhiro Baba Yoshimitsu Shimoyama 《Journal of sports sciences》2017,35(2):189-195
The purpose of this study was to determine the installation of the backstroke start device reduces 15-m time. Thirteen college swimmers participated in this study. The aerial start and underwater motions were recorded with two digital video cameras. The center of mass (CM) of the swimmer, angular displacements and velocities of the shoulder, hip and knee joints were calculated. As an indicator of performance, the 5- and 15-m times were measured. The 5- and 15-m times in the backstroke start device condition were significantly shorter than in the non-backstroke start device condition. The vertical velocities of the CM at hand-off and toe-off in the backstroke start device condition were significantly greater than in the non-backstroke start device condition, while there was no significant difference in the CM horizontal velocity at toe-off. As a result, the height of the great trochanter at entry of the fingertips, with the backstroke start device, was 15 cm higher than in the non-backstroke start device condition. In addition, the CM horizontal velocities at 5 m in the backstroke start device condition were significantly greater than those of the non-backstroke start device. Thus, the use of the backstroke start device may reduce the 15-m time by diminution of the entry area. 相似文献