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111.
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Biopolymer flocculant produced by an Enterobacter sp. 总被引:11,自引:0,他引:11
Haruhiko Yokoi Takashi Yoshida Shingo Mori Jun Hirose Sachio Hayashi Yoshiyuki Takasaki 《Biotechnology letters》1997,19(6):569-573
A new biopolymer flocculant was produced by Enterobacter sp. BY-29. Flocculating activity increased in the presence of Al , Fe or Fe . The flocculant had flocculating activity not only in inorganic suspensions of kaolin and active carbon but also in organic suspensions of cellulose and yeast. The flocculant was an acidic polysaccharide consisting of glucose, galactose, xylose and galacturonic acid, and its MW was about 2.5 ¥ 10 6 Da. 相似文献
114.
Isao Yokoi Yukiko Namba Hideaki Kabuto Kazunori Inada Motoyuki Iida Akitane Mori Norio Ogawa 《Neurochemical research》1996,21(10):1187-1192
Since nitric oxide (NO) is synthesized by nitric oxide synthase (NOS) froml-arginine (Arg) which has an amidino group in its molecule, we, examined the effect of 29 kinds of Arg analogues on neuronal
NOS (nNOS) activity in the rat brain. None of the Arg analogues acted as a substrate for nNOS. Diamidinocystamine, hirudonine,
and guanethidine inhibited nNOS activity to 67.3%, 64.2% and 74.1%, respectively, but their inhibitory efficiency was lower
than NG-monomethyl-l-arginine (to 36.5%) which is a well known NOS inhibitor. Dimethylguanidine and N-benzoylguanidine also significantly inhibited
nNOS activity to 88.0% and 90.7%, respectively. Whereas almost all of the NOS inhibitors previously reported were synthesizdd
by substituting the amidino nitrogen of Arg, none of these new inhibitors were substituted at this position. Furthermore,
hirudonine, which is a naturally occurring compound, was thought to act as an agonist at polyamine binding site of the N-methyl-d-aspartate type of glutamate receptor complex. It is also interesting that guanethidine, an antihypertensive agent, inhibit
nNOS activity. These new drugs are useful for the investigation not only of the chemical nature of nNOS but also of the physiologic
function of NO. 相似文献
115.
Hiromichi Yokoi Yoshihiro Tsuruo Tadayuki Miyamoto Kouki Kitagawa Shiroh Futaki Kazunori Ishimura 《Histochemistry and cell biology》1996,106(4):359-366
The localization of 5α-reductase was immunohistochemically studied in the anterior pituitary of male rats, using a polyclonal
antibody against 5α-reductase rat type 1. The immunoreactive cells were concentrated in the central region and on the border
of the intermediate lobe in the anterior pituitary, but not in the intermediate or posterior lobe. The immunoreaction was
located mostly in the cytoplasm and occasionally in the cell nuclei. The immunoreactive cells showed alterations in size and
number and in the intensity of the immunoreaction after gonadectomy. One week after castration, the cells became larger and
the immunoreactivity increased. Two weeks after castration, the number of immunoreactive cells increased. Double immunostaining
using antiluteinizing hormone β-subunit or anti-follicle stimulating hormone β-subunit antibody revealed that most of the
cells containing 5α-reductase were gonadotrophs. Electron microscopically, the immunoreactive cells showed lamelliform rough
endoplasmic reticulum and a depletion of secretory granules 1 week after castration. One week later, the rough endoplasmic
reticulum was developed and dilated and the number of secretory granules increased. These results suggest that 5α-reductase
is located in the gonadotrophs of rat anterior pituitary and that it is involved in the feedback regulation of gonadotropin
secretion by androgens. 相似文献
116.
Haruhiko Yokoi Michiko Shiraki Jun Hirose Sachio Hayashi Yoshiyuki Takasaki 《Biotechnology Techniques》1996,10(10):789-792
Summary Xanthan had a flocculating activity in a kaolin suspension and high flocculating activity was obtained in the suspension (pH 7.0) adding Al3+, Fe3+ or Fe2+. Xanthan had high flocculating activity not only in other inorganic suspensions such as active carbon and acid clay but also in organic suspensions of cellulose and yeast. From these flocculation properties, xanthan is anticipated to be utilized in wide areas as a new biodegradable, harmless biopolymer flocculant. 相似文献
117.
The promoter of an anther tapetum-specific gene,Osg6B, was fused to a-glucuronidase (GUS) gene and introduced into rice byAgrobacterium-mediated gene transfer. Fluorometric and histochemical GUS assay showed that GUS was expressed exclusively within the tapetum of anthers from the uninucleate microspore stage (7 days before anthesis) to the tricellular pollen stage (3 days before anthesis). This is the first demonstration of an anther-specific promoter directing tapetum-specific expression in rice.Abbreviations
GUS
ßGlucuronidase 相似文献
118.
Yokoi Haruhiko Maeda Yukihide Hirose Jun Hayashi Sachio Takasaki Yoshiyuki 《Biotechnology Techniques》1997,11(6):431-433
Clostridium butyricum immobilized on porous glass beads in a column reactor evolved H 2 at 715 and 1,150 ml/l.h, with H 2 yields of 2.3 and 1.9 mol H 2 /mol glucose, at retention times of 2.0 and 1.0 h, respectively, with a medium containing 0.5 g glucose/l in continuous cultures without pH control. 相似文献
119.
120.
Transcriptional and morphological changes in the transition from mycetophagous to phytophagous phase in the plant‐parasitic nematode Bursaphelenchus xylophilus 下载免费PDF全文