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951.
Distribution Of Guanidino Compounds In Bovine Brain 总被引:2,自引:1,他引:1
952.
False positive reaction for carcinoembryonic antigen in Paget cells. Immunohistochemical observation
S Sumitomo Y Tatemoto S Fukui T Nakamura S Fukushima N Ito M Mori 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(4):395-399
Paget cells from cases of mammary and extramammary Paget's disease were examined for carcinoembryonic antigen (CEA) and CEA-related antigens by the immunoperoxidase method. Paget cells showed a conspicuous positive reaction with antiserum to CEA, but were negative when nonspecific cross-reacting-antigen (NCA)-absorbed antiserum to CEA, or a monoclonal antibody to CEA was used as the detecting agents. Paget cells may contain large amounts of NCA antigen or CEA-related substances. 相似文献
953.
H Matsumoto C Kaneko K Yamada T Takeuchi T Mori Y Mizuno 《Nucleic acids symposium series》1986,(17):5-8
In order to search for improved syntheses of 9-(2-hydroxyethoxymethyl) guanine and related antiviral agents, we tried several well documented general procedures (viz., fusion method) for the synthesis of N-glycosyl bond. Product distribution on alkylation of 4,5-disubstituted imidazoles as well as 2,6-disubstituted purines may depend upon the nature of alkylating agents (viz., 2-oxa-1,4-butanediol diacetate or 1-bromo-2-oxa-4-butanol acetate) and reaction conditions. A procedure for the synthesis of acyclovir and its N2-acetyl derivative could be improved to a considerable extent. 相似文献
954.
Human chorionic gonadotropin, reaction with tetranitromethane 总被引:1,自引:0,他引:1
955.
Horseradish peroxidase (HRP, 10 mg/100 g body weight) was intravenously injected into rats in order to investigate the nature of the compartments involved in the transcellular transport of the protein through hepatocytes into bile. Double cytochemistry for HRP and the marker enzymes for cytoplasmic organelles was used. HRP was shown to be taken up by hepatocytes via vesicles at the sinusoidal surface, some of which were positive for 5'-nucleotidase activity. HRP was then found in the smooth-surfaced vesicles and tubules which were negative in 5'-nucleotidase, glucose 6-phosphatase, thiamine pyrophosphatase and acid phosphatase activity, suggesting that the tubular structures are neither the endoplasmic reticulum, the Golgi apparatus nor lysosomes. Biochemical studies revealed that the lead procedures used for the double cytochemistry did not inhibit the peroxidatic activity of HRP, and conversely that HRP did not interfere with the marker enzyme activity. Such cytochemical observations seemed to be supported by the observation that administration of monensin (3.5 mg/100 g) and chloroquine (5 mg/100 g), which markedly altered the structure of the Golgi apparatus and lysosomes, respectively, slightly altered the biliary excretion of HRP but not to a significant extent. 相似文献
956.
957.
Glycoprotein O (gO) is conserved among betaherpesviruses, but little is known about the maturation process of gO in human herpesvirus 6 (HHV-6). We found that HHV-6 gO maturation was accompanied by cleavage of its carboxyl terminus and required coexpression of gH and gL, which promoted the export of gO out of the endoplasmic reticulum (ER). Finally, we also found that gO was not required for HHV-6A growth in T cells. 相似文献
958.
Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(10):2045-2047
A key intermediate, 2-isocyano-3-hydroxybutyrate (III) was isolated from a reaction of isocyanoacetate (I) with acetaldehyde (II) in the presence of Et3N. It was found that III was readily converted into 2-isocyanocrotonate (V) and 2-isocyano-2-(1′-hydroxyethyl)-3-hydroxybutyrate (VI) which are undesirable compounds for the synthesis of threonine. However, by use of a metal catalyst (e.g. NiCl2 or PdCl2), the isocyano-hydroxy compound (III) was selectively converted into 5-methyl-4-alkoxycarbonyl-2-oxazoline (IV) which is an important precursor of threonine. Furthermore, chemical properties of IV were examined; the results suggested that cis-oxazoline was relatively sensitive to acid, base and heat.On the basis of these results, the reaction of I with II was carried out using Et3N-PdCl2 as a catalyst to obtain threo-threonine (85% purity) in a good yield (85%). 相似文献
959.
960.
H C Lee M Yamaguchi T Ikenoue I Miyakawa N Mori 《Prostaglandins, leukotrienes, and essential fatty acids》1992,47(2):117-121
Surfactant rich lipid (lipid) was extracted from cell free 10,000 x g pellets of amniotic fluid. White blood cells (WBC) were isolated from human donors. 36 x 10(7) WBC and 5 g rabbit lung were incubated with pretreated lipid or dipalmitoyl lecithin (lecithin). Leukotrienes (LTs) were identified by high performance liquid chromatography (HPLC) and bioassay, and quantified by radioimmunoassay. Peaks of LTC4 and LTD4 on HPLC and guinea-pig ileum contraction could be identified in lipid and lecithin groups, but not in the control group. LTC4 production by lipid and lecithin groups was significantly higher than that by the control group. An involvement of amniotic fluid surfactant in leukotriene production is suggested. 相似文献