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排序方式: 共有1214条查询结果,搜索用时 15 毫秒
1.
Kenji Masumoto Tomoki Shono Shin-ichiro Takasugi Noboru Hotta Kazutaka Fujishima Yukihide Iwamoto 《Journal of electromyography and kinesiology》2007,17(5):596-604
This study aimed to examine whether walking in water produces age-related differences in muscle activity, stride frequency (SF), and heart rate (HR) response. Surface electromyography (EMG) was used to evaluate muscle activities in six older and six young subjects while they walked in water immersed to the level of the xiphoid process. The trials in water utilized the Flowmill which consists of a treadmill at the base of a water flume. The measurement of maximal voluntary contraction (MVC) of each muscle was made prior to the gait analysis. The %MVCs, which refer to the surface EMG measures, from the gastrocnemius of the older subjects were significantly lower than those of the young subjects, in every experimental condition (P<0.05). In contrast, the %MVCs from the rectus femoris (P<0.05) and the biceps femoris (P<0.001) of older subjects were significantly greater than those of young subjects in every experimental condition. Moreover, the SFs of older subjects were also significantly greater than those of young subjects (P<0.05), while the HR responses of older and young subjects were similar. In conclusion, the older subjects had increased hip musculature activity and decreased ankle plantar flexor activity while walking in water, compared with the young subjects. 相似文献
2.
T Kondo E Kano 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1987,52(4):627-633
The present study was performed to elucidate the role of non-thermal effects (cavitation and direct effects) of ultrasound, in simultaneous combination with X-irradiation on the cytotoxicity of mouse L cells. Firstly, mouse L cells were exposed to X-rays and ultrasound (1 MHz continuous wave, spatial peak temporal average intensity; 3.7 W/cm2) simultaneously at 37 degrees C under O2 or Ar saturated conditions to examine the cavitational effect of ultrasound. Secondly, cells were exposed to X-rays and ultrasound at 37 degrees C under N2O saturated conditions, which suppresses the cavitation, to examine the direct effects of ultrasound. The cavitational effect under O2 and Ar saturated conditions induced an exponential decrease in cell survival, and resulted in an additive effect on cell killing with the combination of X-rays and ultrasound. The direct effect in the N2O conditions induced no cell killing and did not modify the cell killing induced by X-rays. These results suggested that the non-thermal effects of ultrasound did not interact synergistically with X-rays for cell killing. 相似文献
3.
The development of the bovine ileal mucosa was studied with particular reference to maturation during the fetal and neonatal period. In this region, by 4-5 months of fetal development, vacuolation of the epithelial cells had occurred on the villi, and the goblet and absorptive cells in the crypts were present. By 6-9 months, the villi were longer and more numerous than in the previous stages. At the same time, the vacuolated cells could be seen predominantly on the upper half of each villus. The absorptive cells and goblet cells were more distinct in the crypt and lower half of each villus. Moreover, the goblet cells showed differences in mucin, while in the submucosa the lymphoid follicles were seen to have enlarged to become a prominent feature of the Peyer's patches at this stage. At birth, in suckled animals, the ileal cells on the lower area of each villus and in the crypt appeared more like mature cells. In contrast, there were numerous inclusion bodies in epithelial cells on the upper half of each villus. They appeared in the apical portion of the cytoplasm as vacuoles with stainable or dense contents. By 1 week, however, epithelial cells no longer contained inclusion bodies, and absorptive and goblet cell populations had begun to emerge from the crypts. These histological results suggest that the bovine ileal mucosa has two distinct turning points during its development in the fetus and the neonate. Initially all the mucosal structures are present in fetuses at 6-7 months of gestation, and then the vacuolated cells covering the ileal villi are replaced by mature, nonpinocytosing epithelium which emerges from the crypts on or before the 7th day after birth (ileal closure). 相似文献
4.
A method of nonsurgical embryo collection in the Shiba goat, a native Japanese miniature goat breeding nonseasonally, was developed. The apparatus used for flushing the uterus was made on the model of the two-way catheter for cows. Embryo collection was performed on days 5 to 7 in 37 females superovulated with PMSG and hCG and resulted in successful recovery of 69 embryos in 19 females (51.4%). The average number of embryos collected from each successful female was 3.6. The recovery rate of embryos calculated on the basis of the number of embryos recovered and corpora lutea observed by culdoscopy in 15 successful females was 89.5%. This nonsurgical method seem to be efficient enough for collecting morulae and blastocysts in Shiba goats. 相似文献
5.
Takashi Ooba Hideyuki Hayashi Sachiko Karaki Manabu Tanabe Kyoichi Kano Masafumi Takiguchi 《Immunogenetics》1989,30(2):76-80
The primary structure ofHLA-B51 andHLA-Bw52 suggested thatHLA-B51 was derived fromHLA-Bw52 by the combination of a genetic exchange withHLA-B8 and a point mutation. To investigate the evolution of theHLA-B5 cross reactive group, theHLA-B35 gene was cloned and the primary structure was determined.HLA-B35 is identical toHLA-Bw58 except in the α1 domain. The α1 domain ofHLA-B35 except Bw4/Bw6-associated amino acids is identical to that ofHLA-B51
*, which was suspected to be an intermediate gene betweenHLA-B51 andHLA-Bw52. These data suggest thatHLA-B35 has evolved fromHLA-Bw58 in two steps; an in vivo replacement of the α1 domain withHLA-B51 and genetic exchange with one of theHLA-Bw6 genes. These three genes andHLA-Bw58 are postulated to share a common ancestor. 相似文献
6.
Toshiho Nishita Hidetoshi Oshige Hiroharu Matsushita Yutaka Kano Masao Asari 《The Histochemical journal》1989,21(1):8-14
Summary Carbonic anhydrase III has been localized using the avidin-biotin-glucose oxidase complex (ABC) method in the submandibular gland of the rat and hamster. This isozyme, which is predominant in skeletal muscle, was observed in intercalated duct, striated duct and excretory duct cells in the rat submandibular glands. In contrast, only some striated duct cells in hamster submandibular glands were stained. 相似文献
7.
Yuzuru Mikami Sen Feng Yu Katsukiyo Yazawa Kazutaka Fukushima Akio Maeda Jun Uno Kiyoshi Terao Naoki Saito Akinori Kubo Ken -ichiro Suzuki 《Mycopathologia》1990,112(2):113-118
During our studies on toxic substances from clinically isolated Nocarida, a new isolate identified as Nocardia otitidiscaviarum from cutaneous nocardiosis was found to produce a toxic substance called HS-6 that had strong in vitro as well as in vivo toxicity. The mouse intraperitoneal LD50 value was 1.25 mg/kg and the ED50 value for L1210 cultured cells was 0.3 ng/ml. The structure of HS-6 was determined and found to belong to the 16-membered macrocyclic group with a molecular formula of C43H68O12. HS-6 also showed activity against pathogenic fungi such as Cryptococcus neoformans. 相似文献
8.
HU-1 mutants of Escherichia coli deficient in DNA binding 总被引:1,自引:0,他引:1
We constructed four mutants of the Escherichia coli hupB gene, encoding HU-1 protein, by synthetic oligodeoxyribonucleotide-directed, site-specific mutagenesis on M13mp18 vectors. The HupBR45 protein contained alterations of Arg58----Gly and Arg61----Gly, and the HupBF3, HupBK2 and HupBA1 proteins contained Phe47----Thr, Lys37----Gln and Ala30----Asp alterations, respectively. HupBF3 and HupBR45 were unable to maintain normal cell growth in a hupA-hupB-himA triple mutant at 42 degrees C, mini-F or RSF1010 proliferation, or Mu phage development in a hupA-hupB double mutant, whereas HupBA1 and HupBK2 supported these cellular activities. DNA-affinity column chromatography showed that the HupBF3 and HupBR45 had reduced affinities to DNA. These observations indicate that two highly conserved Arg residues in the arm structure of the C-terminal half of the HU-1 molecule and a Phe residue in the short beta-sheet connecting the two halves of the molecule are important for the DNA-binding ability and biological functions of this protein. 相似文献
9.
Ogawa S Yamakawa H Yamanoi J Nishida S Kano Y Takeshima T Tauchi K Nagashima H 《Theriogenology》1988,29(5):1083-1089
An attempt was made to detect the fluorescent bodies (F-body), using Quinacrine mustard (Q-M) staining in the spermatozoa from eight mammalian species (human, bull, boar, dog, rabbit, rat, mouse, and mastomys) as well as in the cock (used as negative control). Sperm suspension, prepared after rinsing by repeated centrifugation with phosphate buffered saline (PBS), was either stained with Q-M for 24 h or treated with protease and then stained with Q-M for 60 min. The final concentration of Q-M in the mixed staining sperm suspension was 0.025 mg/ml. The examination using a reflecting fluorescent microscope revealed that the F-body found in human sperm was also present in the sperm of all the mammals but not in the cock after 24 h of staining. The enzyme-treated specimens showed higher incidences of F-bodies than specimens stained for 24 h without enzymatic digestion. These findings strongly suggest that the F-body is commonly present in the spermatozoa of many mammalian species. 相似文献
10.