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1.
2.
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
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.
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
7.
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
8.
K Mizukawa T Ogura I Yamamoto T Mitsui E Katayama Z Ota N Ogawa 《Regulatory peptides》1988,21(1-2):167-172
The localization of receptors for atrial natriuretic polypeptide (ANP) in the glomerulus of the rat was studied by electron microscopic autoradiography using 125I-labeled ANP. A total of 1,134 silver grains counted in 30 glomeruli were distributed as follows: processes of the podocytes (36.4%), cell bodies of the podocytes (14.8%), basement membrane (12.3%), endothelial cells (6.3%), mesangial cells (7.7%) and others, for example the vascular spaces (22.5%). This finding indicates that ANP binding sites are mainly localized on the foot processes of the podocytes in the glomerulus. 相似文献
9.
The hydrophobicity of the nontransformed and transformed androgen receptor from rat submandibular gland and heat shock protein 90 (hsp90) from rat submandibular gland and liver was characterized by using high-performance hydrophobic-interaction chromatography on TSK gel Ether-5PW. In the absence of molybdate, cytosol [3H]R1881-androgen receptor complexes were mainly eluted in the 1.3 M region (Peak 1) with a small peak in the 0.8 M region (Peak 2) of a descending salt gradient (2 to 0 M) of ammonium sulfate. In the presence of molybdate, Peak 2 was predominant. When labeled-cytosol was applied after being heated at 25 degrees C for 30 min, a third peak (Peak 3) at around 0.64 M ammonium sulfate was newly observed. Peaks 2 and 3 were observed, while Peak 1 completely disappeared with the labeled-cytosol precipitated at 40% saturated ammonium sulfate. The Stokes radius of Peak 1 was 7 nm, and of Peak 2 was 8 nm. Both peaks were retained poorly by DNA-cellulose but bound rather well to DEAE-cellulose. These results suggest that these two peaks represent the nontransformed receptor, indicating that there are isoforms of the nontransformed androgen receptor which are distinguished by their hydrophobic properties and Stokes radii. Peak 3 had a Stokes radius of 5 nm and preferentially bound to DNA-cellulose, suggesting that this peak corresponds to the transformed receptor. These results indicated that the transformation of the androgen receptor accompanies the enrichment of the hydrophobicity of the receptor molecule. Hsp90 purified from rat livers and hsp90 in the cytosol both from livers and submandibular glands were eluted from Ether-5PW at 0.8 M ammonium sulfate, at almost the same position as Peak 2. This finding suggests that the enrichment of hydrophobicity on transformation is due to dissociation of hsp90 from the nontransformed androgen receptor. 相似文献
10.
CAM Photosynthesis under Drought Conditions in Kalanchoe blossfeldiana Grown with Nitrate or Ammonium as the Sole Nitrogen Source 总被引:1,自引:0,他引:1
K. blossfeldiana Poelln. cv. Hikan was grown in vermiculite,supplied daily with nutrient solution containing 1 mM (or 10mM) nitrate or ammonium as the sole nitrogen source. The nitrate-grownplants had more activity of CAM (Crassulacean acid metabolism)photosynthesis (nocturnal CO2 uptake in the shoot and nocturnalincreases of titratable acidity and malate content in the leaves)than the ammonium-grown plants. Interruption of the solutionsupply for 5 or more days (drought conditions) increased theactivity of CAM photosynthesis in nitrate- or ammonium-grownplants, and the diurnal CO2 uptake pattern in the nitrate-grownplants shifted from weak-CAM to full-CAM.The difference in the activity of CAM photosynthesis betweennitrate- and ammonium-grown plants increased under the droughtconditions. When the solution was resupplied, the activity ofCAM photosynthesis rapidly decreased to the levels before theinterruption. The physiological mechanism and ecological significanceof the effect of the nitrogen source on CAM photosynthesis arediscussed (Received January 5, 1988; Accepted April 13, 1988) 相似文献