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11.
Kiyotaka Chinzei Kantaro Fujioka Hiroshi Kitazato Itaru Koizumi Tadamichi Oba Motoyoshi Oda Hisatake Okada Toyosaburo Sakai Yoshihiro Tanimura 《Marine Micropaleontology》1987,11(4)
Downcore changes in microfossil assemblages and oxygen isotope ratios in three piston cores recovered from the Northwestern Pacific, off central Japan, show that the subtropical Kuroshio front was located to the south of C-4 core site (Lat. 33° N) during the last glacial. The front then advanced northward, passing over the C-4 site and the C-6 site (34.6° N) at about 13 ka and 10 ka, respectively, and reached the C-1 core site (36° N) at about 7 ka. After 5.5 ka it retreated to the area between the C-1 and C-6 sites. A brief but significant cold event, the readvance of the cold Oyashio Current, is recognized between 11 and 10 ka in the two northern cores, but the current did not reach the southern C-4 site. A contemporaneous cold event is known in the North Atlantic, and the cooling was probably a global phenomenon likely to be associated with lowering of sea level. Contamination of isotopically light water is apparent between 14 and 11 ka in the marked change in isotopic composition of benthic foraminifers. Oxygen isotope ratios of planktonic foraminifers show that prior to the advance of the Kuroshio front, the surface water at these core sites was isotopically lighter than the Kuroshio water at that time. 相似文献
12.
Mutagenesis of human granulocyte colony stimulating factor 总被引:9,自引:0,他引:9
T Kuga Y Komatsu M Yamasaki S Sekine H Miyaji T Nishi M Sato Y Yokoo M Asano M Okabe 《Biochemical and biophysical research communications》1989,159(1):103-111
To define the structure-function relationship, we have made a number of mutants of human granulocyte colony-stimulating factor (hG-CSF) by in vitro mutagenesis. The results indicate that most of the mutations located in the internal and C-terminal regions of the molecule abolished the activity, whereas the mutants without N-terminal 4, 5, 7, or 11 amino acids retained the activity. N-terminal amino acids were also altered by cassette mutagenesis using a synthetic oligonucleotide mixture. Among them, KW2228, in which Thr-1, Leu-3, Gly-4, Pro-5 and Cys-17 were respectively substituted with Ala, Thr, Tyr, Arg and Ser, showed more potent granulopoietic activity than that of intact hG-CSF both in vitro and in vivo. 相似文献
13.
Yasuaki Kagotani Setsuji Hisano Yoshihiro Tsuruo Shigeo Daikoku Yasuhiko Okimura Kazuo Chihara 《Cell and tissue research》1990,262(1):47-52
Summary Certain populations of arginine vasopressin (AVP) neurons in the magnocellular paraventricular nucleus became immunoreactive for neuropeptide Y (NPY) when rats were treated with colchicine or monosodium glutamate (MSG). The co-storage of these peptides was examined by empooying a post-embedding electron-microscopic immunohistochemistry technique using goldlabeled antibodies to the two peptides. In colchicinetreated rats, the neuronal perikarya contained numerous secretory granules showing co-storage of the two peptides. The cells of the MSG-treated rats were characterized by having well-developed Golgi bodies with the granular structures also co-storing the two peptides, although the secretory granules in the perikarya were rather fewer than in the colchicine-treated rats. It is concluded that the destruction of the arcuate nucleus by MSG-treatment may potentiate the synthesis of NPY in AVP neurons, the synthesis of which is latent in intact animals. 相似文献
14.
Hajime Yamasaki Eizo Okamoto Toshinori Komatsu Yuich Manabe Sohei Shinka 《Cancer immunology, immunotherapy : CII》1990,31(2):107-114
Summary The levels of a variety of immunological parameters were examined in 203 preoperative patients with hepatocellular carcinoma (HCC) at various stages (I–IV). The changes in the peripheral blood lymphocyte (PBL) count, the serum level of immunosuppressive acidic protein and the degree of the skin reaction to purified protein derivative were associated significantly with the stage of HCC progression. However, the percentages of lymphocyte subsets, mitogenic responsiveness of PBL and serum immunoglobulin concentration remained at the levels of stage I. Further study demonstrated that in patients undergoing hepatic artery ligation, there were statistically significant correlations between the PBL count, immunosuppressive acidic protein concentration and intensity of the skin reaction to purified protein derivative, assayed 1 month after surgery, and the prognosis. HCC-specific immunity was examined in 34 patients treated by hepatic resection or hepatic artery ligation using in vitro responses of PBL to HCC extracts (ATS test). This test was performed using culture medium containing added arginine. None of the PBL from the patients showed a positive response to allogeneic HCC extracts, but the PBL from 12 patients (9 hepatic resections, 3 hepatic artery ligations) were stimulated significantly (SI 2.5) with autologous HCC extracts. In 7 of 9 hepatic resection patients who were positive in the ATS test, tumor recurrence was identified. Statistical analysis indicated that the ATS test result was significantly correlated with tumor recurrence in hepatic resection patients. Autologous-PBL-stimulating activities were isolated in a fraction at pH 8.3 and in fractions at pH 6.7–7.0 by chromatofocusing of the crude extract. Although identification of the HCC-specific antigen remains to be done, use of the above fractions may simplify the ATS test procedure and improve its sensitivity. 相似文献
15.
Yoshihiro Akimoto Akiko Obinata Hiroyoshi Endo Professor Hiroshi Hirano 《Cell and tissue research》1988,254(3):481-485
Summary The effect of epidermal growth factor (EGF) on the basement membrane structure of chick embryonic skin cultured in a chemically defined medium (BGJb) containing 20 mM hydrocortisone, and EGF at 10, 50, or 100 ng/ml supplemented with 5% delipidized fetal calf serum, was examined by electron microscopy. During development of the epidermis in vitro, EGF (100 ng/ml) caused striking changes to occur in the basement membrane structure and in the keratinization process. The basement membrane frequently became discontinuous with many gaps apparent in section, and occasionally became folded following detachment from the basal surface of the epidermis and protruded into the underlying dermis. In the basal and intermediate cells of EGF-treated epidermis, tonofilament bundles were decreased in number, while desmosomes and hemidesmosomes revealed no significant changes in morphology. 相似文献
16.
Nichola J. K. Hole Edmundo Lamoyi Masanori Komatsu Nagaradona Harindranath Glendowlyn O. Young-Cooper Rose G. Mage 《Immunogenetics》1988,28(2):99-107
In order to investigate linkage, we used serum allotypes of the two rabbit C
isotypes and restriction fragment length polymorphisms (RFLPs) of the genes for V
, C
, and T-cell receptor C
. The inheritance of these genetic markers was studied through backcross and F2 matings. Southern analysis and hybridization of genomic DNA with a C probe detected a 5 kb Pst I fragment linked to expression of the K2bas1 allotype and the presence of the 1b
bas gene and a 6.6 kb Pst I fragment linked to the expression of the K1b9 allotype, the presence of the 2
bas2 gene and lack of expression of the K2bas1 allotype. A V probe detected a 1.3 kb Eco RI fragment linked to the presence of the 1b
bas gene and expression of the K2bas1 allotype. In contrast, the 9 or 14 kb Eco RI RFLP (C
a or C
b) detected with a Tcr
chain probe segregated independently from C allotypes and RFLPs. It has previously been found that C and C
are also unlinked in man, whereas in the mouse they are linked at a distance of 8 centimorgans. 相似文献
17.
Sueyoshi Kuni; Kubo Yoshihiro; Yamagishi Kenji; Ogura Nagao; Ochiai Kuniyasu; Fukushima Kazuo; Ikeda Tadashi; Nakagawa Hiroki 《Plant & cell physiology》1988,29(6):975-980
Two monoclonal antibodies, 17(3)9 and 36(79)4, were preparedagainst nitrate reductase from Spinacia oleracea L. leaves.An enzyme-linked immunosorbent assay showed that 17(3)9, butnot 36(79)4, reacted more strongly to heat-denatured than nativeantigen. These antibodies inhibited NADH-nitrate reductase aswell as its various partial activities including reduced methylvilogen-nitrate reductase, reduced flavin mononucleotide-nitratereductase and NADH-cytochrome c reductase activities, but notNADH-ferricyanide reductase activity. Immunoblotting after electrophoreticseparation of nitrate reductase fragments obtained by Staphyrococcusaureus V8 protease digestion of native enzyme revealed thatthe two monoclonal antibodies bind to different epitopes locatedon the 28 kDa of the NADH-ferricyanide reductase domain. (Received October 2, 1987; Accepted June 9, 1988) 相似文献
18.
Oncogenic transformation by fractionated doses of neutrons 总被引:1,自引:0,他引:1
R C Miller D J Brenner C R Geard K Komatsu S A Marino E J Hall 《Radiation research》1988,114(3):589-598
Oncogenic transformation was assayed after C3H 10T1/2 cells were irradiated with monoenergetic neutrons; cells were exposed to 0.23-, 0.35-, 0.45-, 5.9-, and 13.7-MeV neutrons given singly or in five equal fractions over 8 h. At the biologically effective neutron energy of 0.45 MeV, enhancement of transformation was evident with some small fractionated doses (below 1 Gy). When transformation was examined as a function of neutron energy at 0.5 Gy, enhancement was seen for cells exposed to three of the five energies (0.35, 0.45, and 5.9 MeV). Enhancement was greatest for cells irradiated with 5.9-MeV neutrons. Of the neutron energies examined, 5.9-MeV neutrons had the lowest dose-averaged lineal energy and linear energy transfer. This suggests that enhancement of transformation by fractionated low doses of neutrons may be radiation-quality dependent. 相似文献
19.
Shuzo Miyamoto Yoshihiro Matsuda Shin-ichiro Sano Hiroshi Shiraki Hachro Nakagawa 《Neurochemical research》1992,17(7):723-727
The activity of ammoniagenesis from guanine nucleotides was found to increase significantly in rat brain after infusion of kainic acid into the striatum. Among the enzymes involved in degrading guanine nucleotides, nucleoside diphosphatase was markedly increased in the lesioned striatum. The enzyme activity began to increase 2 days after the infusion, and reached the maximum on the 13th day, the level being 4 times as high as that of the intact contralateral region. The increased activity was due to Type L enzyme, judging from its substrate specificity. Puromycin and cycloheximide inhibited this increase, indicating that the increased activity resulted from an increase in the net synthesis of the enzyme. These findings suggest that Type L NDPase might play some important roles in gliosis after neuronal lesion. 相似文献
20.
Gyu-Chul Hwang Yoshihiro Ochiai Shugo Watabe Kanehisa Hashimoto 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,161(2):141-146
Summary Heavy meromyosin subfragment-1 (S1) was prepared by -chymotrypsin from myosin of carp acclimated to either 10°C or 30°C for a minimum of 5 weeks. The objective of these studies was to document thermally-induced changes in the myosin molecule and to extend previous observations. Ca2+- and K+ (EDTA)-ATPase activities of cold-acclimated carp S1 were 1.1 and 0.8 mol Pi·min-1·mg-1, respectively, and these values did not differ significantly from those of warm-acclimated carp. The inactivation rate constant (KD) of S1 from cold-acclimated carp was 32.1x10-4· s-1, compared to 13.2x10-4·s-1 for warm-acclimated carp. The maximum initial velocity of acto-S1 Mg2+-ATPase activity at pH 7.0 in 0.05 M KCl was 9.3 s-1 with cold-acclimated carp, about 3.7 times higher than that for warm-acclimated carp. However, no significant difference was observed in the apparent affinity of S1 to actin. Peptides maps of the heavy chain of S1 were different and suggested distinct isoforms for the myosins from warm- and cold-acclimated muscle.Abbreviations
ATPase
adenosine 5-triphosphatase
-
DTNB
5,5-dithiobis (2-nitrobenzoic acid)
-
DTT
dithiothreitol
-
EDTA
ethylenediaminetetraacetic acid
-
EGTA
ethyleneglycol bis (-aminoethylether)-N,N,N,N-tetraacetic acid
-
K
D
inactivation rate constant
-
K
m
apparent dissociation constant
-
P
i
inorganic -phosphate
-
PMSF
phenylmethane-sulfonyl fluoride
-
S
1
heavy meromyosin subfragment-1
-
SDS
sodium dodecyl sulfate
-
SDS-PAGE
SDS-polyacrylamide gel electrophoresis
-
TPCK
N-tosyl-l-phenylalanyl chloromethyl ketone
-
V
max
maximum initial velocity 相似文献