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1.
Munirul Alam Shin-ichi Miyoshi Ikuyo Maruo Chiemi Ogawa Sumio Shinoda 《Microbiology and immunology》1994,38(6):467-470
The protease elaborated by Vibrio mimicus is known to possess hemagglutinating ability to chicken erythrocytes, the well-known HA/protease. A non-protease hemagglutinin (HA) with strong agglutinating ability towards rabbit erythrocytes was obtained from 32 hr culture supernatant of a pathogenic environmental strain of V. mimicus. This HA (V. mimicus HA: VMHA) appeared stable at relatively higher temperature and agglutinated the erythrocytes from rabbit, guinea pig and mouse but not the erythrocytes from chicken, bovine, horse and sheep. Simple sugars, metal ions and chelating agents failed to inhibit the activity of VMHA. The activity of VMHA was found to be sensitive to digestion by proteolytic enzymes including HA/protease. These results provide evidence for the existence of novel HA other than HA/protease in V. mimicus. 相似文献
2.
3.
Hidekatsu Yokoyama Shin-ichi Niwa Kenji Itoh Reiko Mazuka 《Biological cybernetics》1996,75(2):137-140
On the basis of a temporal model of animal behavior we conducted temporal analysis of eye movements in schizophrenic subjects
(n=10) and normal controls (n=10). We found a fractal property in schizophrenic subjects, the fixation time of eye movement during reading ambiguous and
difficult sentences showing a clear inverse power law distribution. An exponential distribution of a nonfractal nature was
found in normal controls.
Received: 21 July 1995/Accepted in revised form: 30 April 1996 相似文献
4.
5.
A few reports have suggested the possibility that feeding conditions might affect the sexual maturation of free-ranging Japanese
monkeys in provisionized troops. In the present study, the sexual maturation of male monkeys at Takasakiyama in 1984, nine
years after the start of restriction of artificial feeding, was examined externally and histologically and the results were
compared with data obtained in 1971, when artificial foods were abundantly given. Spermatogenesis was not observed in any
of the males under 4.5 years old in the present study, whereas it was noted in some premature 3.5-year-old males and in all
males over 4.5 years old in the 1971 study. The age of sexual maturation thus rose by one or more years over the 13-year period
from 1971 to 1984. The lag in sexual maturation of the males at Takasakiyama in 1984 could have been induced by the restriction
of artificial feeding. 相似文献
6.
Toshikuni Sasaoka Norio Kaneda Yoshikazu Kurosawa Keisuke Fujita Toshiharu Nagatsu 《Neurochemistry international》1989,15(4):555-565
The chromosomal gene for human phenylethanolamine N-methyltransferase (PNMT; EC 2.1.1.28) was isolated from a human genomic library using a cloned human PNMT cDNA as a probe, and the nucleotide sequence was determined. PNMT is encoded in a single gene which consists of three exons. We observed newly the presence of minor PNMT mRNA (type B) besides the major mRNA (type A) as reported previously (Kaneda et al., J. Biol. Chem. 263, 7672–7677, 1988) by Northern hybridization. Type B mRNA carries an approximately 700 nucleotide-long untranslated region in the 5′ terminus. This suggests that two types of mRNA are produced from a single gene through the use of two alternative promoters. A TATA-like sequence locates 30 base pair upstream from the cap site of type A mRNA. Upstream of the cap site, there are several sequences resembling Spl binding sites and glucocorticoid responsive elements, with the latter also found in the first intron. 相似文献
7.
RNA polymerase from the archaebacterium Sulfolobus acidocaldarius was chemically modified with AMP o-formylphenyl ester followed by reduction with borohydride. The modified protein catalyzes the labeling of its own largest subunit when incubated with [-33P]UTP in the presence of poly[d(A-T)]. On cleaving of the labeled protein using cyanogen bromide, hydroxylamine or amino acid-specific endoproteinases for a very brief period, the pattern and size of the radioactive fragments formed are best explained by attachment of the label between Gly843 and Met895 of the largest subunit. In this region there exists a highly conserved sequence which is also found in other archaebacterial, eukaryotic and prokaryotic RNA polymerases. This suggests that the binding site for the initiating substrate of RNA polymerases has been conserved during evolution. 相似文献
8.
Noriaki Murakami Yoshiyuki Tanaka Kunio Takishima Yuzo Minobe Makoto Matsuoka Sei-Ichiro Kiyota Shin-ichi Hatanaka Katsuhiro Sakano 《Journal of plant research》1990,103(4):419-434
We isolated the small subunit of ribulose-1, 5-bisphosphate carboxylase/oxygenase (RuBisCO SSu) from a fern,Asplenium cataractarum and determined its 34 N-terminal amino acid sequence. We obtained a cDNA clone that contains the entire coding region of
the SSu from the same fern species, using synthetic oligonucleotide probes derived from the above amino acid sequence. It
contains a 525 bp open reading frame capable of coding for a polypeptide with 174 amino acids, 31 bp 5′-and 206 bp 3′-noncoding
regions. It was also elucidated that the precursor to the SSu contains a transit peptide of 53 amino acid residues and a mature
protein of 121 residues. We compared the deduced amino acid sequence of the fern SSu with those of 11 other vascular plant
species (including gymnosperms, monocots and dicots). As low as 55% homology was observed between those of a fern and seed
plants. Constancy of the amino acid substitution rate in RuBisCO SSu was supported by our relative rate test. Amino acid substitution
rate per year per site for RuBisCO SSu was calculated to be 0.81×10−9 assuming that the separation between pteridophytes and seed plants arose 380 million years ago. 相似文献
9.
Immunocytochemical studies on the pituitary pars distalis of the Japanese long-fingered bat,Miniopterus schreibersii fuliginosus 总被引:1,自引:0,他引:1
Professor Shin-ichi Mikami Shin Chiba Hitoshi Hojo Kazuyuki Taniguchi Kaoru Kubokawa Susumu Ishii 《Cell and tissue research》1988,251(2):291-299
Summary Immunocytochemical studies were performed to describe the characteristics of cell types and their distribution in the pars distalis of Japanese long-fingered bat, Miniopterus schreibersii fuliginosus, collected at various stages of the reproductive cycle. Six distinct cell types have been identified in the pars distalis by the unlabeled immunoperoxidase technique and by the ABC method. Growth hormone (GH) and prolactin (PRL) cells were immunostained with antisera against chicken GH and ovine PRL. The GH-immunoreactive cells were round or oval orangeophilic cells distributed throughout the pars distalis with prominent aggregation in the posterolateral region. The PRL cells were pleomorphic carminophilic cells that occurred in small groups within the central and dorsocaudal regions of the pars distalis. They were sparsely distributed in the central region of the pars distalis in the hibernating bats, but increased significantly in the pregnant and lactating bats. The adrenocorticotropic (ACTH) cells were large round or polygonal amphophilic cells in the rostroventral and ventrolateral regions of the pars distalis. The thyrotropic (TSH) cells were small rounded or polygonal and distributed mainly in the ventrolateral region of the pars distalis. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) cells were identified immunocytochemically with antisera against the specific beta subunits of ovine LH and rat FSH. There were two populations of LH and FSH cells, one aggregated in the zona tuberalis and the other scattered singly throughout the rest of the pars distalis. The aggregated cells were immunoreactive with both antisera directed to LH and FSH, while scattered cells were reactive solely with antiserum to either LH or FSH and exhibited seasonal variations. In females, the proportional volume of the pars distalis occupied by LH cells was significantly reduced during pregnancy and lactation. No evidence of involution was observed in pars distalis cells except for PRL cells in males or females during hibernation. 相似文献
10.
Responses of seed germination to salinity were examined using 37 species collected from salt marshes, cliffs, and fore (unstable)
and hind (stable) sand dunes along Japanese coasts. For comparison, seed germination of nine inland species was also examined.
The soil salinities in salt marshes ranged from 150 to 300 mmol/L NaCl, whereas those in fore and hind dunes ranged from 0
to 150 mmol/L NaCl, with a few exceptions. Cliff soils showed relatively high salinities up to 300 mmol/L NaCl. Ciff and foredune
soils that encountered a typhoon and storm showed high salinities >300 mmol/L NaCl. Salt tolerance in seed germination of
coastal plants was ordered by comparing the responses of percentage and rate of germination to salinity conditions up to 200
mmol/L NaCl, being in the order of salt marsh>cliff>foredune≅hind dune≅inland. Thse results indicate that salt tolerance in
seed germination of coastal plants is closely related to the salinity conditions of their habitats. Germination experiments
under favorable conditions showed that a high percentage of the seeds of salt marsh species germinate rapidly, those of diff
species germinate slowly and those of foredune species exhibit a low percentage and low rate of germination. It seems that
these germination characteristics contribute to the success of germination at the ‘safe site’ and the subsequent survivorship
of emerged plants in their natural habitats. 相似文献