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81.
Fujimoto H Inokuchi S Ishida H 《The Tokai journal of experimental and clinical medicine》2001,26(4-6):139-145
PURPOSE: This study examined whether a short-term physical or mental training reduces the physiological load and perceived exertion of the in-clothes swimming. METHODS: The study included 24 male inter-collegiate competitive swimmers with no previous experience of the in-clothes swimming. Prior to the training, the subjects performed 200-meter swimming with two styles of swimming, namely the crawl and elementary backstroke, and the degree of perceived exertion in the Borg scale, heart rate, and blood lactic acid level were determined. Following this baseline determination, the subjects were divided into 4 groups with 6 individuals each. These four groups were Group A "in-clothes training", Group B "image training", Group C "swimsuit training", and Group N "no training". Group A and C were lectured on the in-clothes swimming and practiced 7.5 min-long in-clothes swimming per day for a week with the two swimming styles, with Group A subjects wearing daily clothes and Group C subjects in swimsuits. Group B received 15 min of nonphysical mental practice primarily through viewing video recording of swimming performance everyday for a week. No training was given to Group N. At the completion of the training session, the subjects underwent the 2nd 200-meter swimming, and the physiological parameters were determined. RESULTS: The 1st in-clothes swimming load test showed that the elementary backstroke swimming resulted in significantly lower values of heart rate, blood lactic acid level, and perceived exertion than the crawl. For Group N, no difference was observed in the physiological parameters between the 1st and 2nd load test with either the elementary backstroke or crawl. Upon the 2nd in-clothes load test with the elementary backstroke, all three parameters were lower for Group A, B, and C than those seen for the 1st load test, and these differences were statistically significant, except for blood lactic acid in Group A. The 2nd in-clothes load test with the crawl showed that both heart rate and blood lactic acid were lower than those of the 1st load test for all three groups, with the differences in heart rate and blood lactic acid in Group A and that in blood lactic acid in Group B reaching the statistic significance. With respect to perceived exertion, the Borg score determined after the in-clothes load test with the crawl was significantly reduced for Group A, B, and C. The score after the in-clothes load test with the elementary backstroke was significantly reduced only for Group A. CONCLUSION: The elementary backstroke, when practiced in-clothes, imposes a relatively less physiological load. The present training methods can reduce physiological load and/or perceived exertion of the in-clothes swimming. Thus, both image training and swimsuit swimming are equally effective as a training method of the in-clothes swimming. 相似文献
82.
BACKGROUND: Angiotensin II (Ang II), which contracts vascular smooth muscle cells (VSMCs), has been reported to regulate VSMC growth. Recently formed transgenic mice without angiotensinogen or Ang II receptors showed vascular alterations. However, it is still unclear how their VSMCs alter. We explored the role of Ang II via the Ang II type 1a receptor (AT1a) in VSMCs in vivo using AT1a null mutant mice. METHODS: We analyzed the ultrastructure of the intrarenal arteries in AT1a null mutant mice that were homozygous for a targeted disruption of AT1a receptor gene using light and electron microscopy. RESULTS: The structural changes of the intrarenal arteries in AT1a null mutant mice showed the wall thickening, which in the interlobar, arcuate, and proximal interlobular arteries consisted of two additional populations of VSMCs, on the luminal and abluminal sides of the media. The luminal overpopulation of smooth muscle cells (SMCs) was arranged in a longitudinal direction separated by increased interposed elastic laminae. The abluminal overpopulation of SMCs ran in circumferential directions separated from the main population. The cytological structure of VSMCs in AT1a null mutant mice was smaller in size, contained more organelles for protein synthesis and secretion than in control mice, and had poorly developed contractile apparatus. CONCLUSIONS: The lack of AT1a signaling causes structural abnormalities in the renal vascular system and transforms the phenotype of VSMCs into cell proliferation, induces the escape of VSMCs from the circular mechanical integrity, and results in increased synthesis of extracellular matrices. 相似文献
83.
The present paper describes the metabolism of a chiral drug propranolol (PL) using isolated hepatocytes freshly prepared from untreated, PB- or 3-MC-pretreated rats. In order to examine not only the existence of enantioselectivity but also the effect of enzyme inducer (PB or 3-MC) on PL metabolism, 500 microM PL (RS-PL, R(+)-PL or S(-)-PL) was incubated at 37 degrees C using 8 x 10(6) cells/ml isolated rat hepatocytes. Then, the elimination amount of PL and the formation amounts of eight kinds of the metabolites including ring hydroxylated metabolites (4-OH-, 5-OH- and 7-OH-PL) and side chain metabolites (NDP, AcNDP, PGL, NLA and NAA) were simultaneously determined by HPLC. By 3-MC- and PB-pretreatment, a significant increase was noticed in PL elimination and also in the formation of PL metabolites, NDP, NLA and NAA. Furthermore, the presence of enantioselectivity was observed, i.e. the substrate R(+)-PL was always eliminated faster than the substrate S(-)-PL. Regarding the metabolite formation, NDP, AcNDP and NAA were dominantly produced from R(+)-PL, and NLA, PGL and the ring hydroxylated metabolites from S(-)-PL. In all cases of PL elimination and the metabolite formation, the amounts of the metabolites derived from RS-PL indicated the mean values of the respective amounts derived from R(+)-PL and S (-)-PL. Using the three kinds of isolated rat hepatocytes mentioned above, the kinetic parameters of NDP-formation at 37 degrees C for 10 min were calculated using RS-PL, R(+)-PL or S(-)-PL as a substrate. From the pseudo values of V'max/K'm (microliter/min.8 x 10(6) cells), the easiest formation of NDP from R(+)-PL was observed in the rat hepatocyte system pretreated with 3-MC. 相似文献
84.
We attempted to detect the bcr-abl fusion gene and ras gene family in CML by the in vitro focus forming assay and the tumorigenicity assay. Eight of 14 chronic phase and both of two blastic phase cases showed transforming activity in the tumorigenicity assay. However, only one chronic phase sample was positive in the in vitro focus forming assay. Among these 10 transformants, we found N-ras activation in one chronic phase, and K-ras activation in another chronic phase case. The bcr-abl fusion gene was activated in one chronic phase and all of the blastic phase cases by the tumorigenicity assay. The present result showed that the bcr-abl fusion gene transfected N1H3T3 cells formed tumors in nude mice in contrast to the in vitro focus forming assay. The bcr-abl fusion gene may play important roles in the progression as well as the pathogenesis of CML. 相似文献
85.
Takeshi Saito Seiji Morita Shigeaki Inoue Isotoshi Yamamoto Sadaki Inokuchi 《Forensic Toxicology》2008,26(1):27-30
A detailed procedure for sensitive analysis of acetaminophen (APAP) in human hair segments by gas chromatography-mass spectrometry
is reported. The limit of quantitation was as low as 0.1 ng/mg. The linear concentration range of the assay was 0.1–10 ng/mg.
The interday and intraday coefficients of variation were below 10%. The method was successfully applied to hair analysis of
APAP in an actual poisoning case. 相似文献
86.
87.
S Inokuchi M Ueda K Hashimoto H Handa T Mitomi 《The Tokai journal of experimental and clinical medicine》1991,16(5-6):223-229
Human epidermal keratinocytes, immortalized by the introduction of SV40-adenovirus recombinants (9), were maintained in a low calcium (0.15 mM) defined medium. When differentiation was induced by a higher extracellular calcium concentration (1.5 mM), these cells altered in shape and developed stratification with formation of desmosomes, while they demonstrated limited terminal keratinization. The expression of involucrin, one of the precursor proteins of the cornified envelope, became elevated as the cell density increased, but was not affected by calcium. These results indicate that the SV40 immortalized human keratinocytes, maintained in a low calcium defined medium, partially respond to changes in extracellular calcium concentration. 相似文献
88.
R Saito A B Jurado I Inokuchi I Koide T Tomotsu M B Mohammed Y Ogura 《Acta medica Okayama》1987,41(3):125-131
Temporal bone histopathological findings of two patients with trisomy 18 syndrome are described. Many of the abnormalities previously described were seen in the present cases; namely, atresia of the external auditory canal, aberrant course of the tensor tympani muscle, malformed stapes, aberrant course of the facial nerve with an obtuse angulation at the first genu and displacement of geniculate ganglion cells into the internal auditory canal, shortened cochlea with decreased spiral ganglion cell population, and vestibular anomalies, such as bony and membranous blockage of the superior semicircular canal. Moreover, an extremely underdeveloped malleus and incus continuous with a persistent Meckel's cartilage were observed. 相似文献
89.
Tsugio Nakazawa Yoshio Umegae Shigeru Matsui Ryuzo Fueki Setsuo Kobayashi 《The Journal of asthma》1987,24(6):323-325
A curious inhibitory effect of histamine H-1 and H-2 antagonists on isolated late asthmatic response (LAR) in an asthmatic patient was observed.
When given alone, neither the H-1 nor the H-2 antagonist had an effect on LAR. The combination of drugs, however, provided marked inhibition of LAR. These findings suggest that histamine contributes to some types of LAR. 相似文献
When given alone, neither the H-1 nor the H-2 antagonist had an effect on LAR. The combination of drugs, however, provided marked inhibition of LAR. These findings suggest that histamine contributes to some types of LAR. 相似文献
90.
Katsumi Iga Yasuaki Ogawa Takatsuka Yashiki Tsugio Shimamoto 《Journal of pharmacokinetics and pharmacodynamics》1986,14(2):213-225
A method affording direct estimation of the drug absorption rate from blood level data using arbitrary time intervals has been derived based on the staircase input principle. In the derivation, the drug was assumed to follow linear kinetics where the plasma concentration of the drug after an impulse input is expressed by a multiexponential function. Drug absorption was assumed to occur at a constant rate during each subsequent sampling interval. The absorption rate profiles obtained by the method using several numerical examples were expressed as a set of rectangular pulses. Divergence in the profiles reflected blood sampling measurement errors rather than errors due to the deconvolution. Smoothing of the rate profiles by calculating the mean of the absorption rates between adjacent time intervals gave realistic results. Absorption rate profiles for theophylline obtained by the method using published data gave information on the initiation and termination of the absorption as well as the extent of absorption from the dosage form. 相似文献