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101.
Mana Hayakawa Shinobu Sato Irmina Diala Masaaki Kodama Kumiko Tomoeda‐Mori Kazuya Haraguchi Kazuhiro Tominaga Shigeori Takenaka 《Electroanalysis》2016,28(3):503-507
Electrochemical telomerase assay (ECTA) developed by our group was evaluated in an oral cancer screening using exfoliated oral cells and tissues obtained from patients of oral cancer, mucosa associated disease, or healthy volunteers. Telomerase activity from ECTA is correlated with hTERT mRNA expression level using a real‐time PCR and was increasing in the following order: healthy volunteer group<mucosa associated disease group<oral cancer group. Sensitivity and specificity of ECTA were 88 % and 72 %, respectively when used 17 % of the threshold value based on the receiver operating characteristic curve in ECTA data. 相似文献
102.
Cover Picture: A Strategy to Control the Reactivation of Frustrated Lewis Pairs from Shelf‐Stable Carbene Borane Complexes (Angew. Chem. Int. Ed. 40/2015)
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103.
In the presence of a Ni(0)/NHC catalyst, an equimolar mixture of aliphatic and aryl aldehydes can be employed to selectively yield a single cross-coupled ester. This reaction can be applied to a variety of aliphatic (1°, 2°, cyc-2°, and 3°) and aryl aldehyde combinations. The reaction represents 100% atom efficiency and generates no waste. Mechanistic studies have revealed that the striking feature of the reaction is the simultaneous coordination of two aldehydes to Ni(0). 相似文献
104.
Murahashi T Takase K Oka MA Ogoshi S 《Journal of the American Chemical Society》2011,133(38):14908-14911
We report the oxidative dinuclear addition of a Pd(I)-Pd(I) bond to arenes. The oxidative dinuclear addition products, which have a bi-π-allyl-type arene dipalladium(II) structure, were obtained from [2.2]paracyclophane, anthracene, tetracene, and pentacene. A systematic study of the reaction of [Pd(2)(CH(3)CN)(6)][BF(4)](2) with benzene and polyacenes showed that the larger polyacenes, tetracene and pentacene, afforded the oxidative dinuclear addition products, while benzene, naphthalene, and anthracene gave the π-sandwich Pd(I)-Pd(I) complexes. 相似文献
105.
Masato Ohashi Mitsutoshi Shibata Sensuke Ogoshi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(49):13796-13800
A chemoselective C(sp2) F or C(sp3) F bond activation of hexafluoropropylene (HFP) was achieved by adopting the proper combination of a Lewis acid co‐additive with a ligand which coordinates Pd0. The treatment of [(η2‐HFP)Pd(PCy3)2] with B(C6F5)3 allowed a chemoselective C(sp3) F bond cleavage of HFP to give a unique cationic perfluoroallypalladium complex. In this complex, the coordination mode of the perfluoroallyl ligand was considered to be of the unique η2‐fashion. 相似文献
106.
Synthesis of Cyclobutenes and Allenes by Cobalt‐Catalyzed Cross‐Dimerization of Simple Alkenes with 1,3‐Enynes
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Akira Nishimura Eri Tamai Dr. Masato Ohashi Prof. Dr. Sensuke Ogoshi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(22):6613-6617
Cobalt‐catalyzed cross‐dimerization of simple alkenes with 1,3‐enynes is reported. A [2+2] cycloaddition reaction occurred, with alkenes bearing no allylic hydrogen, by reductive elimination of a η3‐butadienyl cobaltacycle. On the other hand, aliphatic alkenes underwent 1,4‐hydroallylation by means of exo‐cyclic β‐H elimination. These reactions can provide cyclobutenes and allenes that were previously difficult to access, from simple substrates in a highly chemo‐ and regioselective manner. 相似文献
107.
Kumiko Nishioka 《Monatshefte für Mathematik》2002,136(2):123-141
Algebraic independence of the numbers for various d and l, where is a periodic sequence of algebraic numbers and is a sequence of integers satisfying a binary linear recurrence relation, is studied by Mahler’s method.
Received 25 August 2000; in revised form 8 January 2002 相似文献
108.
Takayuki Kokawa Hideto Saigusa Iichirou Aino Chiharu Matsuoka Tsuyoshi Nakamura Kumiko Tanuma Kazuo Yamashita Seiji Niimi 《Journal of voice》2006,20(3):414-422
SUMMARY: This study identified that physiologically the superior pharyngeal constrictor muscle at the level of the base of the tongue contributes to retrusive movement of the tongue with constriction of the mid-pharyngeal cavity and possesses unique properties in terms of motor speech control along with the genioglossus muscle. From a kinematic study involving trans-nasal fiberscopy and lateral X-ray fluorography, retrusive movement of the tongue was highly correlated with constrictive movement of the mid-pharyngeal cavity. An electromyographic study revealed that the superior pharyngeal constrictor muscle at the level of the base of the tongue contributes to retrusive movement of the tongue and that the genioglossus muscle contributes to protrusive movement. We also noted that this relationship between the activities of these two muscles were in response to postural changes during vowel productions without changes in the acoustic features. These findings suggest that these two muscles act not only antagonistically to produce retrusive and protrusive movement of the tongue, but also they complement each other to conserve the shape of the vocal tract for speech production. The functional relationship between these two muscles could contribute the consecutive movement of human speech production under various conditions and might be useful when applying rehabilitation approaches for the patients with neurological speech and swallowing disorders. 相似文献
109.
Kumiko Hattori Tetsuya Hattori Hiroshi Watanabe 《Probability Theory and Related Fields》1994,100(1):85-116
Summary Diffusion processes on the Sierpinski gasket and theabc-gaskets are constructed as limits of random walks. In terms of the associated renormalization group, the present method uses the inverse trajectories which converge to unstable fixed points corresponding to the random walks on one-dimensional chains. In particular, non-degenerate fixed points are unnecessary for the construction. A limit theorem related to the discrete-time multi-type non-stationary branching processes is applied. 相似文献
110.
Near infrared spectroscopy (NIRS) is used to measure the change in blood volume and oxygenation in the brain cortex induced by functional brain activation. The development of an adequate model to calculate light propagation in the head is very important because the light is strongly scattered in the tissue and this causes ambiguity in the volume of tissue interrogated with a source–detector pair of the NIRS instrument. In this study, a two-dimensional realistic head model is generated from a MRI scan of a human adult head. The light propagation in the head model is calculated by the hybrid Monte Carlo–diffusion method to obtain the change in detected intensity caused by a focal absorption change in the grey matter or in the white matter to discuss the relationship between the depth of the activated region and the sensitivity of the NIRS signal. The sensitivity to the activated region in the white matter steeply decreases with an increase of the depth of the activated region because the spatial sensitivity profile is mainly confined to the grey matter. The contribution of the focal brain activity to the NIRS signal is determined by not only the depth of the activated region from the head surface but also the depth of the activated region from the brain surface. 相似文献