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91.
Henry Szechtman Michael J Eckert Wai S Tse Jonathan T Boersma Carlo A Bonura Jessica Z McClelland Kirsten E Culver David Eilam 《BMC neuroscience》2001,2(1):4-15
Background
A previous report showed that the open field behavior of rats sensitized to the dopamine agonist quinpirole satisfies 5 performance criteria for compulsive checking behavior. In an effort to extend the parallel between the drug-induced phenomenon and human obsessive-compulsive disorder (OCD), the present study investigated whether the checking behavior of quinpirole rats is subject to interruption, which is an attribute characteristic of OCD compulsions. For this purpose, the rat's home-cage was placed into the open field at the beginning or the middle of a 2-hr test.Results
Introduction of the home-cage reduced checking behavior, as rats stayed inside the cage. After 40 min, checking resurfaced, as quinpirole rats exited the home-cage often. An unfamiliar cage had no such effects on quinpirole rats or saline controls.Conclusions
Checking behavior induced by quinpirole is not irrepressible but can be suspended. Results strengthen the quinpirole preparation as an animal model of OCD compulsive checking. 相似文献92.
Alpha,beta-unsaturated 2-acyl imidazoles are a novel and practical class of dienophiles for the DNA-based catalytic asymmetric Diels-Alder reaction in water. The Diels-Alder products are obtained with very high diastereoselectivities and enantioselectivities in the range of 83-98%. The catalytic reaction was performed on a 1.0 mmol scale, and the imidazole auxiliary was removed readily. 相似文献
93.
Abbasi R Abdou Y Abu-Zayyad T Adams J Aguilar JA Ahlers M Andeen K Auffenberg J Bai X Baker M Barwick SW Bay R Bazo Alba JL Beattie K Beatty JJ Bechet S Becker JK Becker KH Benabderrahmane ML BenZvi S Berdermann J Berghaus P Berley D Bernardini E Bertrand D Besson DZ Bindig D Bissok M Blaufuss E Blumenthal J Boersma DJ Bohm C Bose D Böser S Botner O Braun J Brown AM Buitink S Carson M Chirkin D Christy B Clem J Clevermann F Cohen S Colnard C Cowen DF D'Agostino MV Danninger M Daughhetee J 《Physical review letters》2011,106(14):141101
IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18) eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence. 相似文献
94.
Boersma AJ de Bruin B Feringa BL Roelfes G 《Chemical communications (Cambridge, England)》2012,48(18):2394-2396
DNA-based catalysis can be used to control the enantioselectivity of copper-catalysed Diels-Alder and Friedel-Crafts reactions to produce either enantiomer of the product by changing the denticity of the ligand coordinated to the Cu(II) ion, even though the DNA adopts a right handed helical conformation only. 相似文献
95.
[Structure: see text] Cotrimerization of arynes and electron-deficient alkenes selectively affords dihydrophenanthrenes or ortho-olefinated biaryls, depending on the catalytic system employed. Our findings support a mechanism involving benzyne and a metallacycloheptadiene as key intermediates. 相似文献