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771.
Hiroaki Sawai Takeshi Itoh Kazumi Kokaji Kazuo Shinozuka 《Journal of molecular evolution》1997,45(3):209-215
Oligomerization of α-adenosine 5′-phosphorimidazolide (α-ImpA) has been done in an aqueous solution using a uranyl-ion catalyst
or a poly(U) template as a model process of prebiotic synthesis of RNA with α-glycosidic linkage. α-Oligoriboadenylates up
to hexamer were formed from α-ImpA by the uranyl-ion catalyst. 3′-5′ Linkage was mainly formed in the oligomerization. The
poly(U) template mediated the oligomerization of α-ImpA, but to a very low extent. The yield and chain length of the resulting
α-oligomers were far lower than those of the corresponding β-oligomer formation under the same conditions. Physico-chemical
properties of α-oligoriboadenylates are presented along with those of the corresponding β-oligoriboadenylates. The results
indicate that β-RNA is more advantageous than α-RNA from the points of their synthesis and properties.
Received: 10 February 1997 / Accepted: 31 March 1997 相似文献
772.
773.
The mass gain of polyphagous grasshoppers fed a mixture of intrinsically inferior plants is often greater than that of grasshoppers fed each inferior plant alone. We examined the cause of this greater mass gain by assessing the food processes of a polyphagous grasshopper in detail. Food processes were divided into five stages: consumption, fecal mass, assimilated food, approximate digestibility, and efficiency of conversion of digested food (ECD). Using final-stadium female nymphs of the polyphagous grasshopper Parapodisma subastris, we compared the mass gain of nymphs fed the inferior plants Polygonum cuspidatum and Weigela hortensis or the superior plant Artemisia princeps. The mass gain of nymphs fed a single inferior plant was less than that of nymphs fed the superior plant because of reduced ECD. However, the mass gain of nymphs fed a mixture of the two inferior plants was not only greater than that of nymphs fed a single inferior plant, but also did not differ from that of nymphs fed the superior plant. Since consumption by nymphs fed the mixture was greater than that by nymphs fed P. cuspidatum and smaller than that by nymphs fed W. hortensis, and since the ECD of nymphs fed the mixture was greater than that of nymphs fed W. hortensis and was not different from that of nymphs fed P. cuspidatum, consumption and ECD appeared to cause the greater mass gain in nymphs fed the mixture. 相似文献
774.
G Yoshino M Matsushita E Maeda M Morita K Nagata K Matsuba T Tani R Horinuki Y Kimura T Kazumi 《Hormones et métabolisme》1992,24(7):306-309
The present study was conducted to see the effect of probucol on streptozotocin diabetes in rats. After 2 weeks of a 1% probucol diet, 35 or 50 mg/kg of streptozotocin were intravenously injected into male Wistar rats. All the rats became diabetic 2 days after treatment. Thereafter, in order to see the effect of probucol on spontaneous recovery from streptozotocin diabetes, 25 mg/kg of streptozotocin was injected into rats after two weeks of probucol diet and the diet was continued for additional two weeks. All the rats with a standard diet (group CS, n = 13) and 12 of 13 rats with probucol diet (group PS) became diabetic 2 days after streptozotocin injection. One rate from group PS did not develop diabetes. Two weeks after injection, only 4 of 13 rats in groups CS showed recovery, while 11 of 12 rats in group PS showed recovery from streptozotocin diabetes (p less than 0.05). The average blood glucose levels in group PS were significantly lower than group CS (10.5 +/- 4.6 vs 18.5 +/- 0.6 mM, p less than 0.05). In addition, the pancreatic insulin content of group PS was 8 times greater than that of group CS (0.75 +/- 0.24 vs 0.09 +/- 0.03 mmol/pancreas, p less than 0.01). Thus, the in vivo diabetogenic action of streptozotocin could not be reduced by pretreatment with probucol. However, recovery from streptozotocin diabetes was induced by subsequent treatment with probucol. The precise mechanisms for this phenomenon were not known; but the present findings suggest the protective effect of probucol on beta-cell damage induced by small dose of streptozotocin. 相似文献
775.
Walter Vichnewski Ilda Kazumi Shuhama Richard C. Rasanske Werner Herz 《Phytochemistry》1976,15(10):1531-1532
The eudesmanolides granilin and ivasperin were isolated from Ambrosia polystachya DC. 13C-NMR spectra are reported for these and other naturally-occurring ring A-hydroxylated isoalantolactones. 相似文献
776.
Laing David G.; Prescott John; Bell Graham A.; Gillmore Robin; James Catherine; Best D.John; Allen Suzanne; Yoshida Masaaki; Yamazaki Kazumi 《Chemical senses》1993,18(2):161-168
As part of a larger cross-cultural study of the chemoreceptiveabilities and preferences of Australians and Japanese, thisstudy investigated the differential taste sensitivity of subjectsfrom both cultures. The results indicate that there are no significantdifferences between the abilities of subjects from the two culturesto discriminate small increments (just noticeable differences)in the intensities of the four common tastants: sucrose, sodiumchloride, citric acid and caffeine. Furthermore, the Weber ratiosfound with each tastant were within the range of those reportedin the literature. These findings represent further evidencefor the view that differences in responses of subjects fromdifferent cultures to chemosensory stimuli are restricted topreference behaviour arising from experience rather than fromgenetically-based influences.
3Present address: Faculty of Science and Technology, Universityof Western Sydney, Bourke Street, Richmond, NSW 2753, Australia
4Present address: CSIRO Biometrics Unit, Institute of AnimalProduction and Processing, PO BOx 52 North Ryde NSW 2113, Australia 相似文献
777.
Shinji Sugiura Shinya Yamahira Masato Tamura Kazumi Shin Mayu Shibuta Taku Satoh Yui Matsuzawa Gen Fujii Fumiki Yanagawa Michihiro Mutoh Masumi Yanagisawa Ryuji Kato Hirofumi Matsui 《Biotechnology and bioengineering》2023,120(6):1492-1505
We report an automated cell-isolation system based on fluorescence image analysis of cell aggregates cultured in a photodegradable hydrogel. The system incorporates cell culture in a humidified atmosphere with controlled CO2 concentration and temperature, image acquisition and analysis, micropatterned light exposure, and cell collection by pipetting. Cell aggregates were cultured on hydrogels, and target cells were selected by phase contrast and fluorescence image analysis. After degradation of the hydrogel by exposure to micropatterned UV light, cell aggregates were transferred to a collection vessel by robotic pipetting. We assessed the system for hydrogel degradation, recovery of target cells, and contamination by off-target cells. We demonstrated two practical applications of our method: (i) in cell aggregates from MCF-7-RFP strains in which 18.8% of cells produced red fluorescent protein (RFP), we successfully obtained 14 proliferative fluorescence-positive cell aggregates from 31-wells, and all of the isolated strains produced a higher proportion of RFP production than the original populations; (ii) after fluorescent immunostaining of human epidermal growth factor receptor 2 (HER2) in cancer cells, we successfully isolated HER2-positive cells from a mixed population of HER2-positive and -negative cells, and gene sequence analysis confirmed that the isolated cells mainly contained the target cells. 相似文献
778.
779.
Hiromi Mutsuura Kenji Kanbara Mikihiko Fukunaga Kazumi Yamamoto Ikumi Ban Kana Kitamura Yoshihide Nakai 《Applied psychophysiology and biofeedback》2009,34(4):291-298
Patients presenting with functional somatic syndrome (FSS) are common, and the symptoms are persistent and difficult to treat
for doctors and costly for society. The aim of this study was to clarify the common pathophysiology of FSS, especially the
relationship between hypothalamic-pituitary-adrenal (HPA) axis function and psychological characteristics of patients with
FSS. The subjects were 45 patients with FSS and 29 healthy controls. Salivary free cortisol was measured in the morning, and
psychological tests examining depression, anxiety and quality of life (QOL) were performed on the same day. In patients with
FSS, depressive scores showed a significant negative correlation with salivary free cortisol in the morning, although in healthy
controls, cortisol showed a significant positive correlation with depressive scores. In addition, the correlation between
other psychological test scores and cortisol secretion in patients with FSS contrasted with that of controls. The relationship
between cortisol and depression, anxiety or QOL, suggests that the HPA axis of patients with FSS is dysfunctional and does
not function properly when patients with FSS are under stress. This dysfunction may explain the pathology of medically unexplained
persistent symptoms of patients with FSS. 相似文献
780.