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1.
The molybdenum and tungsten dinitrogen-organonitrile complexes trans-[M(N2)(NCR)(dppe)2] (2, M=Mo; 4, M=W; R=Ph, C6H4Me-p, C6H4OMe-p, Me; dppe=Ph2PCH2CH2PPh2) underwent double protonation at the nitrile carbon atom with loss of N2 and a change in oxidation state to +4 on treatment with hydrochloric acid to afford the cationic imido complexes trans-[MCl(NCH2R)(dppe)2]+. The solid-state structure of trans-[WCl(NCH2CH3)(dppe)2][PF6]·CH2Cl2 was determined by single-crystal X-ray analysis. Protonation of complexes 2 by fluoroboric acid or hydrobromic acid also formed the similar imido complexes trans-[MoX(NCH2R)(dppe)2]+ (X=F, Br). In contrast, the dinitrogen complex trans-[Mo(N2)2(dppe)2] reacted with two equiv. of benzoylacetonitrile, a nitrile with acidic CH hydrogen atoms, to give the nitrido complex trans-[Mo(N)(NKCCHCOPh)(dppe)2] (12), which was accompanied by evolution of dinitrogen and the formation of 1-phenyl-2-propen-1-one in high yields. For complex 12, the zwitterionic structure, where the anionic enolate ligand PhC(O+)=CHCN coordinates to the cationic Mo(IV) center through its nitrogen atom, was confirmed by spectroscopic measurements and single-crystal X-ray analysis. A unique intermolecular aromatic C---HO hydrogen bonding was observed in that crystal structure. Complex 12 is considered to be formed via the cleavage of the CN triple bond of benzoylacetonitrile on the metal. A reaction mechanism is proposed, which includes the double protonation of the nitrile carbon atom of the ligating benzoylacetonitrile on a low-valent molybdenum center. 相似文献
2.
Shinichi Ikemoto Seiji Wada Masato Kamizuru Nobuyuki Hayahara Taketoshi Kishimoto Masanobu Maekawa 《Cancer immunology, immunotherapy : CII》1992,34(5):289-293
Summary The authors examined interleukin-2 (IL-2) production and interferon (IFN) production of peripheral blood mononuclear cells in 28 patients with renal cell carcinoma and 17 control subjects. The peripheral blood was obtained prior to the initiation of therapeutic procedures. The patients were divided into two groups according to tumor size, 5 cm and >5 cm. The production of IL-2 and IFN was measured by immunoradiometric assay. As a result, in the patients with tumors >5 cm, IL-2 and IFN production was impaired. However, in the patients with tumors 5 cm, IFN production was enhanced, though IL-2 production was not significantly different from that of the control subjects. There was no significant correlation between IL-2 production and IFN production. 相似文献
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Weng Kong Sung Masanobu Komatsu Georgiana M. Jagiello 《Molecular reproduction and development》1986,14(3):245-254
A combination of autoradiography and air-dried techniques was used to calculate the duration of the major meiotic stages in the first wave of spermatogenesis in the newborn mouse. The data indicated that the entry into meiosis occurred asynchronously over 2 days, and the time required for each stage and the total cycle was constant. These time intervals were nearly identical with those estimated for adult animals in the present study and by other authors. 相似文献
5.
Kihachi Saito Kenji Ishii Norihisa Fujita Masanobu Nakahiro Reizo Inoki 《Neurochemistry international》1985,7(6):1033-1036
Two parameters of Ca2+ dynamics in brain preparations (45Ca-uptake to slices and [3H]nitrendipine binding to membrane fractions) were measured in naive and chronic morphine-administered rats. While morphine did not have any effect on 45Ca-uptake to striatal slices in normal Krebs-Ringer solution, it inhibited K+-stimulated 45Ca-uptake to slices. Furthermore, the effect of morphine was antagonized by naloxone. Inhibition of K+-stimulated 45Ca-uptake to striatal slices by morphine was not observed in preparations obtained from chronic morphine-administered rats (6 mg/kg/b.i.d./7 days). In membrane fractions, [3H]nitrendipine binding increased by 34% in striatum following chronic morphine treatment, whereas no change was observed in the cortex and hippocampus. The results will be discussed in relation to the phenomena underlying chronic morphine administration. 相似文献
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Kazuko Yamaguchi-Shinozaki Masanobu Mino John Mundy Nam-Hai Chua 《Plant molecular biology》1990,15(6):905-912
We have analyzed in transgenic tobacco the expression of a chimeric gene containing 5 sequences of the rice rab-16B gene fused to the -glucuronidase (GUS) reporter gene. This construct, a translational fusion (–482 to +184) including 14 amino acids of the RAB-16B protein, is expressed only in zygotic and pollen-derived embryos. In zygotic embryos, GUS activity begins to accumulate 10 days after flowering (daf), and increases until seed maturation at 25 daf. Immunological measurements of endogenous abscisic acid (ABA) accumulation in these seeds showed a close parallel between hormone levels and GUS activity. However, GUS activity could not be reproducibly induced by treatment of immature embryos with ABA (10 M). Neither GUS activity nor GUS mRNA could be detected in leaves of transgenic tobacco even after ABA treatment. In contrast, GUS activity could be induced to high levels in pollen-derived embryos by treatment with ABA. Our results show that 482 bp of 5 sequences of the rice rab-16B promoter can confer in transgenic tobacco developmentally regulated expression in embryos but not ABA-responsive expression in vegetative tissues. 相似文献
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Shoko Fujiwara Mitsuhiro Sawada Junichiro Someya Nobuhiro Minaka Masanobu Kawachi Isao Inouye 《Journal of phycology》1994,30(5):863-871
The nucleotide sequences of rbcL genes encoding the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) were determined from six species of Prymnesiophyta to clarify their phylogenetic relationships. Molecular phylogenetic trees were constructed using PAUP (Phylogenetic Analysis Using Parsimony). These analyses suggest that the Prymnesiophyta, except for the Pavlovales, area relatively stable monophyletic group. Pleurochrysis carterae, included in the Isochrysidales, is a sister species of a monophyletic group consisting of other members of the Isochrysidales, Gephyrocapsa oceanica and Emiliania huxleyi, members of the Coccosphaerales, Calyptrosphaera sphaeroidea and Umbilicosphaera sibogae var. foliosa, and a member of the Prymnesiales, Chrysochromulina hirta. The nucleotide sequence of rbcL from G. oceanica was identical to that from E. huxleyi within the region examined. Our trees show that G. oceanica and E. huxleyi are more closely related to C. hirta than to U. sibogae, C. sphaeroidea, and P. carterae. These results suggest that orders in the Prymnesiophyceae, including the above-mentioned genera, should be redefined. 相似文献
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