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991.
Atrial natriuretic peptide in the ventricles of patients with dilated cardiomyopathy and human foetuses 总被引:2,自引:0,他引:2
Michihisa Jougasaki Hirofumi Yasue Ken Okumura Masashi Mukoyama Yoshihiko Saito Kazuwa Nakao Kiyoshi Takahashi 《The Histochemical journal》1989,21(12):715-720
Summary Immunohistochemical examination of atrial natriuretic peptide (ANP) was performed on endomyocardial biopsy specimens from 8 patients with dilated cardiomyopathy (DCM), 10 human foetal hearts obtained from legal abortions, and 8 adult hearts from autopsy control subjects without cardiovascular diseases. The indirect immunoperoxidase method, using specific monoclonal antibody to -human ANP was employed. Immunoreactivity was observed at the light microscope level in the working ventricular cardiocytes of all patients with DCM as dark-brown, granular deposits. Peripheral plasma levels of ANP in these patients were also increased. In control adult hearts without cardiovascular diseases, immunoreactivity was detected both in the atria and in the ventricular impulse-conducting system, although the working ventricular cardiocytes were not immunoreactive. In foetal hearts, immunoreactivity was detected not only in the atria and ventricular impulse-conducting system, but also in the working ventricular cardiocytes. We conclude that ANP is present in the ventricular impulse-conducting system of the human hearts, and that ANP is also present in the working ventricular cardiocytes in patients with DCM as well as in human foetuses. 相似文献
992.
The mechanism of the rapid inactivation of the cytotoxic activity produced by peritoneal macrophages stimulated with Sarcophaga lectin was investigated. Experiments using radioiodinated tumor killing factor (TKF) showed that the main reason for its inactivation was the rapid dissociation of its trimeric structure into 15-kDa subunits. This dissociation was found to proceed spontaneously in the culture medium irrespective of the presence of macrophages. 相似文献
993.
H Nakai 《Plastic and reconstructive surgery》1986,78(5):604-609
A new method of assembling the framework of the ear with overaccentuated auricular contour is presented. In order to achieve the primary objective of the contour-accentuated framework, any shortage of skin coverage resulting from the increased surface area of the framework is supplied by the resurfaced temporoparietal fascial flap. This is done in 7 cases of microtia reconstruction. The procedure is beneficial for restoring clearly defined auricular relief in ear reconstruction. 相似文献
994.
Site-specific mutagenesis of the human interleukin-1 beta gene: the role of arginine residue at the N-terminal region 总被引:2,自引:0,他引:2
T Kamogashira M Sakaguchi Y Ohmoto K Mizuno R Shimizu K Nagamura S Nakai Y Masui Y Hirai 《Journal of biochemistry》1988,104(5):837-840
Using the expression system for site-specific mutagenesis in Escherichia coli, we have made deletion mutants at the N-terminal or C-terminal region of human interleukin-1 beta (IL-1 beta) consisting of 153 amino acids. The truncated mutants showed that at least 147 amino acids (numbers 4-150) in IL-1 beta are necessary for the exertion of biological activity. When we changed the arginine at the 4th position (Arg4) in IL-1 beta to other specific amino acids, there was a marked difference in the relative extent of biological and receptor binding activities among the mutants. The order of the mutants was Arg4 = Lys4 greater than Gln4 greater than Gly4 = des-Arg4 greater than Asp4. Our results demonstrate that the arginine residue at the 4th position in IL-1 beta is important, but not essential, for IL-1 beta to exhibit its biological and receptor binding activities, and the positive charge at this site plays a key role for IL-1 beta to exert the activities. 相似文献
995.
The effect of the T7 and Escherichia coli DNA-binding proteins at the replication fork of bacteriophage T7 总被引:7,自引:0,他引:7
In this paper we compare the effect of single-stranded DNA-binding proteins of bacteriophage T7 (gene 2.5 protein) and of Escherichia coli (SSB) at the T7 replication fork. The T7 gene 4 protein acts processively as helicase to promote leading strand synthesis and distributively as primase to initiate lagging strand synthesis by T7 DNA polymerase. On a nicked double-stranded template, the formation of a replication fork requires partial strand displacement so that gene 4 protein may bind to the displaced strand and unwind the helix catalytically. Both the T7 gene 2.5 protein and E. coli SSB act stoichiometrically to promote this initial strand displacement step. Once initiated, processive leading strand synthesis is not greatly stimulated by the single-stranded DNA-binding proteins. However, the T7 gene 2.5 protein, but not E. coli SSB, increases the frequency of initiation of lagging strand synthesis by greater than 10-fold. The results suggest a specific interaction of the T7 gene 2.5 protein with the T7 replication apparatus. 相似文献
996.
Gene 4 protein and DNA polymerase of bacteriophage T7 catalyze RNA-primed DNA synthesis on single-stranded DNA templates. T7 DNA polymerase exhibits an affinity for both gene 4 protein and single-stranded DNA, and gene 4 protein binds stably to single-stranded DNA in the presence of dTTP (Nakai, H. and Richardson, C. C. (1986) J. Biol. Chem. 261, 15208-15216). Gene 4 protein-T7 DNA polymerase-template complexes may be formed in both the presence and absence of nucleoside 5'-triphosphates. The protein-template complexes may be isolated free of unbound proteins and nucleotides by gel filtration and will catalyze RNA-primed DNA synthesis in the presence of ATP, CTP, and the four deoxynucleoside 5'-triphosphates. RNA-primed DNA synthesis may be dissected into separate reactions for primer synthesis and DNA synthesis. Upon incubation of gene 4 protein with single-stranded DNA, ATP, and CTP, a primer-template complex is formed; it is likely that gene 4 protein mediates stable binding of the oligonucleotide to the template. The complex, purified free of unbound proteins and nucleotides, supports DNA synthesis upon addition of DNA polymerase and deoxynucleoside 5'-triphosphates. Association of primers with the template is increased by the presence of dTTP or DNA polymerase during primer synthesis. DNA synthesis supported by primer-template complexes initiates predominantly at gene 4 recognition sequences, indicating that primers are bound to the template at these sites. 相似文献
997.
998.
999.
Yoshihiko Machida 《Ichthyological Research》1989,36(3):363-368
An erratum to this article is available at . 相似文献
1000.
Motomichi Torisu Yoshihiko Hayashi Toshiyuki Ishimitsu Takeshi Fujimura Kazunori Iwasaki Mitsuo Katano Hiroshi Yamamoto Yutaka Kimura Masaharu Takesue Motoharu Kondo Kikuo Nomoto 《Cancer immunology, immunotherapy : CII》1990,31(5):261-268
Summary To examine the clinical efficacy and the mechanism of action of polysaccharide K (PSK), a proteinbound polysaccharide extracted from a Basidiomycetes fungus, a randomized double-blind trial was performed by administering PSK to 56 patients and a placebo to another group of 55 patients after surgical operations on their colorectal cancers. The rate of patients in remission (or disease-free) was significantly higher in the PSK group than in the placebo group; the difference between both groups was statistically significant atP <0.05 by the logrank test. The survival rate of patients was also significantly (P <0.05) higher in the PSK group than in the control group. The most significant laboratory finding was that polymorphonuclear leukocytes from PSK-treated patients showed remarkable enhancement in their activities, such as random and/or chemotactic locomotion, and phagocytic activity, when compared with those in the control group. In conclusion, PSK was useful as a maintenance therapy for patients after their curative surgical operations for colorectal cancer. The beneficial effects were probably due to the activation of leukocyte functions as one of the many biological-response-modifying (activities induced by PSK). 相似文献