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61.
Yutaka Ishigami Yasuo Gama Yoh Sano Siegmund Lang Fritz Wagner 《Biotechnology letters》1994,16(6):593-598
Summary Glucose lipid of notable surfactant properties was produced by using hydrocarbon assimilating bacterium of the bacterial strain MM1. Its surface active properties were notable in spite of ,-hydrophilic and bulky molecule. The critical micelle concentration (cmc) was small (0.165 M); surface and interfacial tension for hexadecane at 0.1 % (pH 7.35) solution, 24.6 and 13.3 mN/m, respectively. The emulsifying action was excellent and comparable to those of rhamnolipids. The micelle has the outer radius. 28.5 Å and inner core, 6.7 Å on the basis of the concentric spherical shell model by means of the small angle X-ray solution scattering measurement.Dedicated to Professor Fritz Wagner on the occasion of his 65th birthday. 相似文献
62.
Shohab Youssefian Michimi Nakamura Hiroshi Sano 《Molecular & general genetics : MGG》1993,237(1-2):187-192
Summary We previously reported the isolation of rgp1, a gene from rice, which encodes a ras-related GTP-binding protein, and subsequently showed that the gene induces specific morphological changes in transgenic tobacco plants. Here, we report the isolation and characterization of an rgp1 homologue, rgp2, from rice. The deduced rgp2 protein sequence shows 53% identity with the rice rgp1 protein, but 63% identity with both the marine ray ora3 protein, which is closely associated with synaptic vesicles of neuronal tissue, and the mammalian rab11 protein. Conservation of particular amino acid sequence motifs places rgp2 in the rab/ypt subfamily, which has been implicated in vesicular transport. Northern blot analysis of rgp1 and rgp2 suggests that both genes show relatively high, but differential, levels of expression in leaves, stems and panicles, but low levels in roots. In addition, whereas rgp1 shows maximal expression at a particular stage of plantlet growth, rgp2 is constitutively expressed during the same period. Southern blot analysis suggests that, in addition to rgp1 and rgp2, several other homologues exist in rice and these may constitute a small multigene family. 相似文献
63.
Possible Involvement of Abscisic Acid in Increases in Activities of Two Vacuolar H+-Pumps in Barley Roots under Aluminum Stress 总被引:1,自引:0,他引:1
Kasai Minobu; Sasaki Masao; Tanakamaru Shigemi; Yamamoto Yoko; Matsumoto Hideaki 《Plant & cell physiology》1993,34(8):1335-1338
Levels of abscisic acid (ABA) in barley roots increased upontreatment with AlCl3. Treatment with AlCl3 or ABA increasedboth ATP-dependent and PPi-dependent H+-pumping activities intonoplast-enriched membrane vesicles. Increase in the H+-pumpingactivities caused by aluminum stress could result from increasedlevels of ABA.
1Present address: Department of Botany, Faculty of Science,Hirosaki University, Hirosaki, Aomori, 036 Japan 相似文献
64.
Takayoshi Yoshida Koji Yamamoto Masao Udo 《European journal of applied physiology and occupational physiology》1993,66(2):155-160
The purpose of the present study was to assess the relationship between the rapidity of increased gas exchange (i.e. oxygen uptake
) and increased cardiac output (
) during the transient phase following the onset of exercise. Five healthy male subjects performed multiple rest-exercise or light exercise (25 W)-exercise transitions on an electrically braked ergometer at exercise intensities of 50, 75, or 100 W for 6 min, respectively. Each transition was performed at least eight times for each load in random order. The
was obtained by a breath-by-breath method, and
was measured by an impedance method during normal breathing, using an ensemble average. On transitions from rest to exercise,
rapidly increased during phase I with time constants of 6.8–7.3 s. The
also showed a similar rapid increment with time constants of 6.0–6.8 s with an apparent increase in stroke volume (SV). In this phase I,
increased to about 29.7%–34.1% of the steady-state value and
increased to about 58.3%–87.0%. Thereafter, some 20 s after the onset of exercise a mono-exponential increase to steady-state occurred both in
and
with time constants of 26.7–32.3 and 23.7–34.4 s, respectively. The insignificant difference between
and
time constants in phase I and the abrupt increase in both
and SV at the onset of exercise from rest provided further evidence for a cardiodynamic contribution to
following the onset of exercise from rest. 相似文献
65.
Toshitsugu Nakamura Masao Hotchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1993,63(1):11-16
DNA strand breaks (nicks) in non-parenchymal cells (NPCs) in CCl4-induced acute or chronic liver injury in rats were detected using an in situ nick translation method; their dynamic changes
were analysed in relation to the proliferation pattern of hepatocytes and NPCs, as revealed by bromodeoxyuridine (BrdU)-up-take.
In acute injury, hepatocyte proliferation started before centrilobular necrosis had occurred, whereas BrdU-labeled sinusoidal
NPCs markedly increased only after centrilobular necrosis was apparent. DNA breakages in NPCs paralleled the proliferation
pattern of these cells, suggesting that nicks are physiological, and reflect proliferation and activated gene expression.
In chronic injury, liver cirrhosis developed after 9 weeks, but BrdU-labeling of hepatocytes was almost the same level as
that in untreated liver. The number of BrdU-labeled NPCs showed only a slight increase, while those with DNA breakages were
much more frequent in the cirrhotic stage, suggesting a significant role for NPCs in the fibrotic process. These results indicate
that DNA strand breaks in NPCs act as a marker for activation states such as proliferation, differentiation and/or activated
gene expression. 相似文献
66.
67.
Watanabe Masao; Nou Ill Sup; Takayama Seiji; Yamakawa Seiyei; Isogai Akira; Suzuki Akinori; Takeuchi Takuji; Hinata Kokichi 《Plant & cell physiology》1992,33(4):343-351
The stigma of Brassica species contain NS-glycoproteins thatexhibit a high degree of structural homology to the S-glycoproteinsof self-incompatibility. Inheritance of and variations in theNS-glycoprotein were studied with reference to self-incompatibility.The detection of NS-glycoproteins was performed by cross-reactionwith an antiserum raised against a purified NS-glycoprotein.In B. campestris, four isoforms of the NS-glycoprotein weredifferentiated by their pI values, but their molecular weightswere identical to one another. The genes for these isoformsof NS-glycoprotein were controlled by alleles at a single locus,tentatively named the NS allele, which was independent of Salleles at both the protein and the DNA level. Segregation ofF2 plants with respect to the self-incompatibility behaviorof pollen tubes can be explained by the S allele model, butit appears not to be affected by the NS alleles. NS-glycoproteinswere found in all 21 species of Brassica and its allies examinedto date. The pI values of these glycoproteins varied among differentspecies. In addition to the isoforms of the NS alleles, maturestigmas contained other groups of proteins that reacted weaklywith the antiserum against the NS-glycoprotein. (Received July 30, 1991; Accepted February 21, 1992) 相似文献
68.
Masao Suzuki Chizuru Tsuruoka Tatsuaki Kanai Takeshi Kato Fumio Yatagai Masami Watanabe 《Biological Sciences in Space》2003,17(4):302-306
We investigated the difference in cell-killing effect and mutation induction between carbon- and neon-ion beams in normal human cells. Carbon- and neon-ion beams were accelerated by the Riken Ring Cyclotron (RRC) at the Institute of Physical and Chemical Research in Japan. Cell-killing effect was measured as the reproductive cell death using the colony formation assay. Mutation induction at the HPRT locus was detected to measure 6-thioguanine-resistant clones. The mutation spectrum of the deletion pattern of exons of induced mutants was analyzed using the multiplex polymerase chain reaction (PCR). Cell-killing effect was almost the same between carbon- and neon-ion beams with similar linear energy transfer (LET) values, while there observed a large difference in mutation frequency. Furthermore, in the case of neon-ion beams 60% of mutants showed total deletions and 35-40% showed partial deletions, while 95-100% of carbon-ion induced mutants showed total deletions. The results suggest that different ion species may cause qualitative and quantitative difference in mutation induction even if the LET values are similar. 相似文献
69.
Hiroyasu Kitashiba Takayoshi Iwai Kinya Toriyama Masao Watanabe Kokichi Hinata 《Sexual plant reproduction》1996,9(3):186-188
The vegetative-to-floral transition ofBrassica campestris cv. Osome was induced by vernalization. Poly(A)+RNA was isolated from the transition shoot apex after 6 weeks of vernalization, the floral apex after 12 weeks of vernalization and the expanded leaves just before vernalization, and cDNAs were synthesized. These cDNAs were used for subtraction and differential screening to select cDNA preferentially present in the transition and floral apices. Nucleotide sequences of the resulting 14 cDNA clones were determined, and northern blot analysis was carried out on six cDNAs. Two cDNA clones which did not show significant similarity to known genes were shown to be preferentially expressed in the floral apex. 相似文献
70.