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11.
12.
Microphotoelectric plethysmography using a rabbit ear chamber 总被引:2,自引:0,他引:2
13.
J L Lin T Asano H Katagiri K Tsukuda H Ishihara K Inukai Y Yazaki Y Oka 《Biochemical and biophysical research communications》1992,184(2):865-870
We engineered the GLUT1 cDNA to delete C-terminal 12 amino acids of encoded GLUT1 protein. This mutated GLUT1 protein expressed in CHO cells by transfection of its cDNA was demonstrated to reside on the plasma membrane by cell surface labeling technique, and retain the transport activity, similar to that of the wild-type GLUT1. In addition, metabolic labeling of the intact cells with 35S indicated that the half-life of the mutated GLUT1 was not significantly different from that of the wild-type GLUT1. These results suggest that C-terminal 12 amino acids of GLUT1 are not important for the transport activity and the stability of the protein. Taken together with our previous results on the mutant without C-terminal 37 amino acids, the amino acids between the 37th and the 13th from the C-terminus appear to be essential for the transport activity. 相似文献
14.
S Takahashi K Uchimaru K Harigaya S Asano T Yamashita 《Biochemical and biophysical research communications》1992,188(1):310-317
Activin A, a homodimer of the beta A chain, regulates hematopoiesis. In a human bone marrow-derived stromal cell line, KM-102, phorbol myristate acetate, tumor necrosis factor-alpha and interleukin-1 beta induced great increases in beta A chain mRNA levels and production of activin A activities. The phorbol ester-induced beta A chain gene expression was inhibited by cycloheximide and down regulation of protein kinase C, whereas the cytokine-induced expression was little affected by these treatments. These results indicate that the inflammatory cytokines directly stimulate beta A chain gene expression via protein kinase C-independent pathways. 相似文献
15.
K. Terasawa T. Fujiwara A. Sakai N. Yanagidaira K. Asano K. Yanagisawa N. Kashimura G. Ueda T. Wu Y. Zhang 《International journal of biometeorology》1996,39(3):111-115
Handgrip force (HF), maximal pinch force (MF), muscle endurance (ME), and the median power frequency (MdPF) of the activity shown in the electromyogram (EMG) were studied at various altitudes in eight normal healthy subjects. MF and ME were measured between the index finger and thumb, and all measurements were obtained at altitudes ranging from 610 to 4860 m during an expedition in the Qinghai Plateau in China. With the change in altitude HF, ME, and MF showed no significant change. Compared to the MdPF at 2260 m on ascent, the MdPF at other altitudes showed a significant decrease (P<0.01). Thus, we conclude that muscle performance (HF, MF, and ME) was not affected by the environment at high altitude. However, MdPF was affected and the mean MdPF at 610 m after the expedition did not recover to initial values of MdPF. We suggest these results may have been affected by fatigue and chronic exposure to the hypobaric hypoxic environment, since the members of the expedition party expressed feelings of sluggishness and fatigue after the expedition. 相似文献
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Nobuyuki Uozumi Yurie Asano Takeshi Kobayashi 《Plant Cell, Tissue and Organ Culture》1994,36(2):183-190
Adventitious shoot primordia were formed on horseradish hairy root cultured in dark. Plantlet formation frequency from the primordia was higher than that from root fragments. Culture for 26 days provided the adventitious shoot primordia, which had the highest potential for plantlet formation (53% explants at 40 days). Benzyladenine supplementation in the dark caused primordium enlargement, but did not increase the number of primordia formed. After adventitious shoot primordia were encapsulated with calcium alginate, kinetin supplementation (2.0–4.0 M) increased the shoot formation frequency (65–80% explants at 20 days) in the light, but also promoted the undesirable formattion of multiple shoots. Supplementation with naphthaleneacetic acid (0.27–5.4 M) in the calcium alginate beads in light enhanced the root emergence from primordia without inhibition of plantlet formation when the encapsulated beads were put on the agar-medium without naphthaleneacetic acid. 相似文献
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3-Methylaspartase was purified 24-fold and crystallized from the crude extract of the cells of a facultative anaerobic bacterium
from soil, strain YG-1002. The molecular mass of the native enzyme was about 84 kDa and that of the subunit was about 42 kDa.
The pH optimum for the deamination reaction of (2S, 3S)-3-methylaspartic acid and those for the amination reaction of mesaconic acid were 9.7 and 8.5; its optimum temperature was
50°C. The enzyme was stable at pH 5.5–11.0 and up to 50°C. The enzyme required both divalent and monovalent cations such as
Mg2+ and K+. The enzyme was inhibited by sulfhydryl reagents, metal-chelating reagents and some divalent cations. The enzyme catalyzed
the reversible amination/deamination reactions between several 3-substituted (S)-aspartic acids and their corresponding fumaric acid derivatives. The enzyme preferentially acted on (2S, 3S)-3-methylaspartic acid and mesaconic acid in the deamination and the amination reactions respectively. The enzyme showed
high similarities in several enzymological properties and N-terminal amino acid sequence with 3-methylaspartase from an obligate
anaerobic bacteriumClostridium tetanomorphum. 相似文献
20.
K. Terasawa A. Sakai Y. Yanagidaira M. Takeoka K. Asano T. Fujiwara K. Yanagisawa O. Kashimura G. Ueda 《International journal of biometeorology》1995,38(3):126-130
To examine cardiopulmonary function during exercise in a mountainous region at moderate altitude, we measured cardiac frequency, oxygen consumption
, and percentage arterial hemoglobin oxygen saturation (%SaO2) before and after a bicycle race with a starting point at 638 m and finishing point at 1980 m. The time required to ascend an elevation of 10 m was prolonged with increasing altitude, and heart rate also increased with altitude. The %SaO2 at the starting point and at the finishing point differed significantly (P<0.01). Faster cyclists exhibited higher %SaO2 and lower
, while slower cyclists exhibited a reduction in %SaO2 and an increase in
immediately after the race. The %SaO2 recovery time was significantly correlated with the racing time (r=0.54,P<0.001). Therefore, the faster cyclists' oxygen debt upon completion of the race may be small and recovery of cardiopulmonary function may be fast, while the slower cyclists' oxygen debt may be large and recovery of cardiopulmonary function may be slow. 相似文献