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51.
Michiko Watanabe Midori Hitomi Kathy van der Wee Florence Rothenberg Steven A Fisher Robert Zucker Kathy K H Svoboda Edie C Goldsmith Kaisa M Heiskanen Anna-Liisa Nieminen 《Microscopy and microanalysis》2002,8(5):375-391
Programmed cell death or apoptosis occurs in many tissues during normal development and in the normal homeostasis of adult tissues. Apoptosis also plays a significant role in abnormal development and disease. Increased interest in apoptosis and cell death in general has resulted in the development of new techniques and the revival of old ones. Each assay has its advantages and disadvantages that can render it appropriate and useful for one application, but inappropriate or difficult to use in another. Understanding the strengths and limitations of the assays would allow investigators to select the best methods for their needs. 相似文献
52.
Akasaka T Kono T Matsunaga Y Wakahara T Nakahodo T Ishitsuka MO Maeda Y Tsuchiya T Kato T Liu MT Mizorogi N Slanina Z Nagase S 《The journal of physical chemistry. A》2008,112(6):1294-1297
The photochemical reaction of La@C82(Cs) with 2-adamantane-2,3-[3H]-diazirine (1) affords the adduct 2 of La@C82(Cs) with adamantylidene (Ad:) in a high selectivity. The two isomers of La@C82(Cs)(Ad), 2a and 2b, are isolated by HPLC and characterized by electron spin resonance, mass, and UV-vis-near-infrared spectroscopies. The electronic properties of 2a and 2b are very similar to that of the pristine La@C82(Cs), suggesting that 2a and 2b retain the essential electronic and structural character of La@C82(Cs). 相似文献
53.
We consider a set X of n noncollinear points in the Euclidean plane, and the set of lines spanned by X, where n is an integer with n ≥ 3. Let t(X) be the maximum number of lines incident with a point of X. We consider the problem of finding a set X of n noncollinear points in the Euclidean plane with t(X) £ ?n/2 ?{t(X) \le \lfloor n/2 \rfloor}, for every integer n ≥ 8. In this paper, we settle the problem for every integer n except n = 12k + 11 (k ≥ 4). The latter case remains open. 相似文献
54.
Xu Q Shen R Ono Y Nagahata R Shimada S Goto M Han LB 《Chemical communications (Cambridge, England)》2011,47(8):2333-2335
A new oxapalladacycle 3 can be conveniently prepared via direct ortho palladation of diphenylphosphinic acid with palladium acetate. Catalysts derived from 3 can efficiently catalyze Markovnikov-type additions of E-H bonds (P(O)-H, S-H and spC-H) to alkynes via a unique catalytic cycle. 相似文献
55.
R Shintani T Ito M Nagamoto H Otomo T Hayashi 《Chemical communications (Cambridge, England)》2012,48(79):9936-9938
A palladium-catalyzed asymmetric synthesis of 2-pyrrolidinones with a quaternary stereocenter at the 3-position has been achieved by the reaction of γ-methylidene-δ-valerolactones with alkyl isocyanates. High enantioselectivity has been realized by employing a newly synthesized chiral phosphoramidite ligand. 相似文献
56.
57.
Suzuki K Sugawa M Kikukawa Y Kamata K Yamaguchi K Mizuno N 《Inorganic chemistry》2012,51(12):6953-6961
Efficient polyoxometalate (POM)-based Lewis acid-base catalysts of the rare-earth-metal-containing POMs (TBA(6)RE-POM, RE = Y(3+), Nd(3+), Eu(3+), Gd(3+), Tb(3+), or Dy(3+)) were designed and synthesized by reactions of TBA(4)H(4)[γ-SiW(10)O(36)] (TBA = tetra-n-butylammonium) with RE(acac)(3) (acac = acetylacetonato). TBA(6)RE-POM consisted of two silicotungstate units pillared by two rare-earth-metal cations. Nucleophilic oxygen-enriched surfaces of negatively charged POMs and the incorporated rare-earth-metal cations could work as Lewis bases and Lewis acids, respectively. Consequently, cyanosilylation of carbonyl compounds with trimethylsilyl cyanide ((TMS)CN) was efficiently promoted in the presence of the rare-earth-metal-containing POMs via the simultaneous activation of coupling partners on the same POM molecules. POMs with larger metal cations showed higher catalytic activities for cyanosilylation because of the higher activation ability of C═O bonds (higher Lewis acidities) and sterically less hindered Lewis acid sites. Among the POM catalysts examined, the neodymium-containing POM showed remarkable catalytic performance for cyanosilylation of various kinds of structurally diverse ketones and aldehydes, giving the corresponding cyanohydrin trimethylsilyl ethers in high yields (13 substrates, 94-99%). In particular, the turnover frequency (714,000 h(-1)) and the turnover number (23,800) for the cyanosilylation of n-hexanal were of the highest level among those of previously reported catalysts. 相似文献
58.
Reiko Azumi Kazumasa Honda Midori Goto Junji Akimoto Yoshinao Oosawa Hiroaki Tachibana 《Molecular Crystals and Liquid Crystals》2013,570(1-2):237-243
Abstract The aromatic ammonium-based layered halide compounds were obtained of bis(4-nitroanilinium)tetrachlorocadmate and bis(2-methyl-4-nitroanilinium) tetrachlorocadmate, aiming at a new type of inorganic-organic hybrid layered material. X-ray diffraction analyses of the single crystals revealed that both of the crystals take an alternate layered structure of the organic bilayer and the inorganic sheet. Cadmium ion and chloride anions form six-coordinated octahedra whose corner anions are shared with the neighboring octahedra for the crystal of bis(4-nitroanilinium)tetrachlorocadmate. In the case of bis(2-methyl-4-nitroanilinium) tetrachlorocadmate crystal the inorganic portion takes distorted four-coordinated tetrahedra. The structure of the inorganic portion for the latter crystal can be considered to be caused by the distortion of a perovskite-type octahedron due to the introduction of a bulky organic molecule. 相似文献
59.
60.
A new resin glycoside (1) was isolated from the aerial part of Ipomoea maxima, together with three known compounds, pescaprein XX (2), stoloniferin X (3), and stoloniferin IX (4). The structure of 1 was elucidated on the basis of 1D NMR spectroscopy, a fragmentation study by APCIMS, and HRESIMS analysis. 相似文献