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51.
S Sumi K Inoue R Hosotani M Kogire R Doi M Yun S Higashide H Minote K Takaori H Kaji 《Life sciences》1990,47(13):1115-1119
The effect of intravenous administration of human epidermal growth factor on the splanchnic blood flows was examined in anesthetized dogs, using an ultrasonic transit-time volume flow meter. Human epidermal growth factor (0.1, 0.5 and 1 microgram/kg) significantly increased blood flows in the portal vein (36.9 +/- 7.4% at 1 microgram/kg) and the superior mesenteric artery (49.0 +/- 16.8% at 1 microgram/kg). Systemic blood pressure monitored simultaneously was significantly decreased (8.4 +/- 1.2% at 1 microgram/kg). This study is the first to demonstrate that intravenous administration of epidermal growth factor increases the portal venous blood flow. 相似文献
52.
Nakazawa Miki; Kakihana Junko; Hisabori Toru; Manabe Katsushi 《Plant & cell physiology》1990,31(6):789-796
Procedures for the purification of native phytochrome from etiolatedpea seedlings without the use of immuno-purification techniquesare described. Phytochrome (in the PFR form) was purified bypolyethyleneglycol fractionation, adsorption to pentyl agaroseand batch elution, chromatography on DEAE-Sepharose, adsorptionto phenyl Toyopearl and batch elution, and chromatography onRed Toyopearl. The resulting phytochrome had specific absorbanceratios (SAR = A666/A280 of PR) that ranged from 0.55 to 0.6.The subsequent chromatography on Sephacryl S-300 yielded verypure phytochrome with a SAR of 0.98. PR and PFR peaks in thedifference spectrum of the phytochrome were centered at 665and 730 nm, respectively. The spectral change ratio (Ar/Afr)of the difference spectrum was unchanged after the chromatographyon phenyl Toyopearl, and the value was 1.051.08, indicatingthat the spectral properties of this preparation were intact.The absorption spectra indicated that the peak absorbance ofPFR was at 728730 nm and that of PR was at 666667nm. These peak positions were essentially same as those obtainedwith the undegraded oat phytochrome. Incubation of the samplepurified on Sephacryl S-300 at 25?C for 5 h in either the PRor PFR form did not result in degradation of the molecule. Therate of dark reversion of PFR observed with the purified peaphytochrome was similar to that observed in vivo. The additionof dithionite had no effect on the reversion rate.
2Present address: Fuji-Gotenba, Research Lab. of Chugai PharmaceuticalCo. Ltd., Gotenba, Shizuoka, 412 Japan (Received February 22, 1990; Accepted May 28, 1990) 相似文献
53.
K Tomoo H Ohishi M Doi T Ishida M Inoue K Ikeda Y Hata Y Samejima 《Biochemical and biophysical research communications》1992,184(1):137-143
The crystal structure of acidic phospholipase A2 from the venom of Agkistrodon halys blomhoffii has been determined by molecular replacement methods based on the known structure of Crotalus atrox PLA2, a same group II enzyme. The overall structures, except the calcium-binding regions, are very similar to each other. A calcium ion is pentagonally ligated to two carboxylate oxygen atoms of Asp-49 and each carbonyl oxygen atoms of Tyr-28, Gly-30 and Ala-31. A reason why the former enzyme functions as monomeric form, while the latter one does as dimer, could be presumed by the structural comparison of these calcium-binding regions. Although Gly-32 is usually participated as a ligand in the coordination with calcium ion in group I PLA2, it is characteristically replaced to Ala-31 in the present structure, and thus the coordination geometry of calcium ion is rather different from the usually observed one. 相似文献
54.
K Nomoto T Takemoto M Maeda Y In M Doi M Inoue T Ishida 《Biochemical and biophysical research communications》1992,187(1):325-331
As an aid for developing a new type of potent insecticide acting on the neuromuscular junction, conformational characteristics of domoic acid and isodomoic acid A, the naturally occurring glutamate agonists, were investigated by X-ray crystal analyses. Conformational comparison with a neuroactive alpha-kainic acid provides information concerning the stereochemical feature responsible for the biological activity. 相似文献
55.
Noriko Osumi-Yamashita Youichirou Ninomiya Hirofumi Doi Kazuhiro Eto 《Development, growth & differentiation》1996,38(1):107-118
Prior to rhombomere development, structures called prorhombomeres appear in the mammalian hindbrain. This study clarifies the developmental relationship between prorhombomeres and their descendent rhombomeres and hindbrain crest cells in mouse embryos by focal dye injections at various levels of prorhombomere A (proRhA), proRhB, and proRhC, as well as at their boundaries. ProRhA gives rise to two rhombomeres, rhombomeres 1 and 2 (r1 and r2), as well as to crest cells that migrate into the first pharyngeal arch, including the trigeminal ganglion. ProRhB develops into r3 and r4 and produces crest cells populating the second arch and acousticofacial ganglion. The anterior portion of proRhC gives rise to r5 and r6 and to crest cells migrating into the third pharyngeal arch and the IXth ganglion; its posterior portion develops into r7 and releases crest cells into the fourth pharyngeal arch region as well as the Xth ganglion. These results suggest that the boundaries between prorhombomeres serve as lineage restrictions for both hind-brain neuroepithelial cells and for segmental origins of crest cell populations in mouse embryos. The Hox code of the mouse head can be schematized in a much simpler way based on this prorhombomeric organization of the hind-brain, suggesting that prorhombomeres primarily underlie mammalian hind-brain segmentation. 相似文献
56.
57.
M. Kato H. J. Bao C.-K. Kang T. Fukui Y. Doi 《Applied microbiology and biotechnology》1996,45(3):363-370
Pseudomonas sp. 61-3 (isolated from soil) produced a polyester consisting of 3-hydroxybutyric acid (3HB) and of medium-chain-length 3-hydroxyalkanoic
acids (3HA) of C6, C8, C10 and C12, when sugars of glucose, fructose and mannose were fed as the sole carbon source. The polyester produced was a blend of homopolymer
and copolymer, which could be fractionated with boiling acetone. The acetone-insoluble fraction of the polyester was a homopolymer
of 3-hydroxybutyrate units [poly (3HB)], while the acetone-soluble fraction was a copolymer [poly(3HB-co-3HA)] containing both short- and medium-chain-length 3-hydroxyalkanoate units ranging from C4 to C12:44 mol% 3-hydroxybutyrate, 5 mol% 3-hydroxyhexanoate, 21 mol% 3-hydroxyoctanoate, 25 mol% 3-hydroxydecanoate, 2 mol% 3-hydroxydodecanoate
and 3 mol% 3-hydroxy-5-cis-dodecenoate. The copolyester was shown to be a random copolymer of 3-hydroxybutyrate and medium-chain-length 3-hydroxyalkanoate
units by analysis of the 13C-NMR spectrum. The poly(3HB) homopolymer and poly (3HB-co-3HA) copolymer were produced simultaneously within cells from glucose in the absence of any nitrogen source, which suggests
that Pseudomonas sp. 61-3 has two types of polyhydroxy-alkanoate syntheses with different substrate specificities.
Received: 9 June 1995/Received last revision: 30 October 1995/Accepted: 6 November 1995 相似文献
58.
59.
Shinichiro Nakamura Wijit Kiatipattanasakul Hiroyuki Nakayama Fumiko Ono Ippei Sakakibara Yasuhiro Yoshikawa Naoaki Goto Kunio Doi 《Journal of medical primatology》1996,25(4):294-300
Abstract: In this study, we immunohistochemically examined the several constituents of senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in aged cynomolgus monkeys. Apolipoprotein E (apoE) deposited in all mature plaques and CAA, and in half of the diffuse plaques. Alpha-1-antichymotripsin (αACT) deposited in half of the mature plaques and in one third of the CAA. Amyloid precursor protein (APP), ubiquitin (Ub), and microtubule-associated protein-2 (MAP-2) accumulated in the swollen neurites of mature plaques. Glial fibrillary acidic protein (GFAP) was detected in the astrocytes and their processes surrounding the mature plaques. Tau was detected in neither the SPs nor CAA. Therefore, mature plaques involved extracellular Aβ, apoE, and αACT, and also astrocytes and swollen neurites. However, diffuse plaques involved only extracellular Aβ and apoE. Since these features, except for tau, were consistent with those in humans, this animal model will be useful for studying the pathogenesis of cerebral amyloid deposition. 相似文献
60.
Streptomyces azureus ATCC 14921 harboured a plasmid pSA1 together with its chromosomal integrated sequence (pSA1int ). The att P site on the plasmid was located at ca 170 bp Bam HI- Sph I fragment by site-specific integration. The free form was generated from the integrated sequence during the development of its host mycelia in the solid culture, but not in the liquid culture. The free form seemed to elicit the formation of spontaneously developing pocks on its host mycelia in the solid culture. 相似文献