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161.
Ethanol, 3 g/kg i.p., did not significantly alter the acute toxicity of amphetamine in the mouse. However, the urinary metabolite pattern was changed, suggesting that ethanol suppressed metabolism of the stimulant during the initial 6 h period. After 24 h, the mouse metabolized the same fraction of a given dose of amphetamine, whether it was given as amphetamine alone or amphetamine mixed with 2,3 or 4 g/kg ethanol. 相似文献
162.
5-Methylcytosine localised in mammalian constitutive heterochromatin 总被引:26,自引:0,他引:26
163.
M. Penchal Reddy R.A. Shakoor Gururaj Parande Vyasaraj Manakari F. Ubai A.M.A. Mohame Manoj Gupta 《自然科学进展(英文版)》2017,27(5):606-614
In the present study, nano-sized SiC (0, 0.3, 0.5, 1.0 and 1.5 vol%) reinforced aluminum (Al) metal matrix
composites were fabricated by microwave sintering and hot extrusion techniques. The structural (XRD, SEM),
mechanical (nanoindentation, compression, tensile) and thermal properties (co-efficient of thermal expansion-
CTE) of the developed Al-SiC nanocomposites were studied. The SEM/EDS mapping images show a
homogeneous distribution of SiC nanoparticles into the Al matrix. A significant increase in the strength
(compressive and tensile) of the Al-SiC nanocomposites with the addition of SiC content is observed. However,
it is noticed that the ductility of Al-SiC nanocomposites decreases with increasing volume fraction of SiC. The
thermal analysis indicates that CTE of Al-SiC nanocomposites decreases with the progressive addition of hard
SiC nanoparticles. Overall, hot extruded Al 1.5 vol% SiC nanocomposites exhibited the best mechanical and
thermal performance as compared to the other developed Al-SiC nanocomposites. 相似文献
164.
165.
Journal of Systems Science and Complexity - The idea of envelope of a family of plane curves is an elementary notion in differential geometry. As such, its implementation in dynamic geometry... 相似文献
166.
正Published online:14 March 2014óScience China Press and Springer-Verlag Berlin Heidelberg 2014Erratum to:Chin.Sci.Bull.(2014)59(5–6):528–532DOI 10.1007/s11434-013-0060-1In the original publication of this paper,the first name and the last name of the first author has been documented 相似文献
167.
168.
Superconductivity in CaCuO2 as a result of field-effect doping. 总被引:2,自引:0,他引:2
J H Sch?n M Dorget F C Beuran X Z Zu E Arushanov C Deville Cavellin M Lagu?s 《Nature》2001,414(6862):434-436
Understanding the doping mechanisms in the simplest superconducting copper oxide-the infinite-layer compound ACuO2 (where A is an alkaline earth metal)-is an excellent way of investigating the pairing mechanism in high-transition-temperature (high-Tc) superconductors more generally. Gate-induced modulation of the carrier concentration to obtain superconductivity is a powerful means of achieving such understanding: it minimizes the effects of potential scattering by impurities, and of structural modifications arising from chemical dopants. Here we report the transport properties of thin films of the infinite-layer compound CaCuO2 using field-effect doping. At high hole- and electron-doping levels, superconductivity is induced in the nominally insulating material. Maximum values of Tc of 89 K and 34 K are observed respectively for hole- and electron-type doping of around 0.15 charge carriers per CuO2. We can explore the whole doping diagram of the CuO2 plane while changing only a single electric parameter, the gate voltage. 相似文献
169.
Pastorello A Della Valle M Smartt SJ Zampieri L Benetti S Cappellaro E Mazzali PA Patat F Spiro S Turatto M Valenti S 《Nature》2007,449(7164):E1-E2
An anomalous transient in the early Hubble-type (S0) galaxy Messier 85 (M85) in the Virgo cluster was discovered by Kulkarni et al. on 7 January 2006 that had very low luminosity (peak absolute R-band magnitude M(R) of about -12) that was constant over more than 80 days, red colour and narrow spectral lines, which seem inconsistent with those observed in any known class of transient events. Kulkarni et al. suggest an exotic stellar merger as the possible origin. An alternative explanation is that the transient in M85 was a type II-plateau supernova of extremely low luminosity, exploding in a lenticular galaxy with residual star-forming activity. This intriguing transient might be the faintest supernova that has ever been discovered. 相似文献
170.
Novel neurotrophic factor CDNF protects and rescues midbrain dopamine neurons in vivo 总被引:1,自引:0,他引:1
Lindholm P Voutilainen MH Laurén J Peränen J Leppänen VM Andressoo JO Lindahl M Janhunen S Kalkkinen N Timmusk T Tuominen RK Saarma M 《Nature》2007,448(7149):73-77
In Parkinson's disease, brain dopamine neurons degenerate most prominently in the substantia nigra. Neurotrophic factors promote survival, differentiation and maintenance of neurons in developing and adult vertebrate nervous system. The most potent neurotrophic factor for dopamine neurons described so far is the glial-cell-line-derived neurotrophic factor (GDNF). Here we have identified a conserved dopamine neurotrophic factor (CDNF) as a trophic factor for dopamine neurons. CDNF, together with its previously described vertebrate and invertebrate homologue the mesencephalic-astrocyte-derived neurotrophic factor, is a secreted protein with eight conserved cysteine residues, predicting a unique protein fold and defining a new, evolutionarily conserved protein family. CDNF (Armetl1) is expressed in several tissues of mouse and human, including the mouse embryonic and postnatal brain. In vivo, CDNF prevented the 6-hydroxydopamine (6-OHDA)-induced degeneration of dopaminergic neurons in a rat experimental model of Parkinson's disease. A single injection of CDNF before 6-OHDA delivery into the striatum significantly reduced amphetamine-induced ipsilateral turning behaviour and almost completely rescued dopaminergic tyrosine-hydroxylase-positive cells in the substantia nigra. When administered four weeks after 6-OHDA, intrastriatal injection of CDNF was able to restore the dopaminergic function and prevent the degeneration of dopaminergic neurons in substantia nigra. Thus, CDNF was at least as efficient as GDNF in both experimental settings. Our results suggest that CDNF might be beneficial for the treatment of Parkinson's disease. 相似文献