排序方式: 共有16条查询结果,搜索用时 0 毫秒
1.
Saify ZS Mushtaq N Khan KM Perveen S Shah ST Abdel-Jalil RJ Fecker M Voelter W 《Chemical & pharmaceutical bulletin》2005,53(1):64-66
A new series of 4-(4'-chlorophenyl)-4-hydroxypiperidine derivatives (2-5), substituted at nitrogen, were synthesized and tested as potential analgesic compounds as well as evaluated for their effect on hypotensive activity. Results showed that all the derivatives exhibit significant analgesic activity in male Wistar rats at a dose of 50 mg/kg of body weight after intramuscular injection, when tested by thermal stimuli (tail flick test). Pethidine was used as reference drug. Compounds 2, 3 and 5 produced reduction in blood pressure in normotensive rat. 相似文献
2.
The properties of passive Q-switched short-cavity dye lasers (SCDL) and passive Q-switched distributed-feedback dye lasers (DFDL) are investigated theoretically by using rate-equation models. The calculations, in agreement with experimental results, predict a significant decrease of the pulse energy fluctuation and the pulse duration of both the SCDL and DFDL, when passive Q-switching is used. 相似文献
3.
We study the functionb(n, d), the maximal number of atoms defined byn d-dimensional boxes, i.e. parallelopipeds in thed-dimensional Euclidean space with sides parallel to the coordinate axes.
We characterize extremal interval families definingb(n, 1)=2n-1 atoms and we show thatb(n, 2)=2n
2-6n+7.
We prove that for everyd,
exists and
.
Moreover, we obtainb*(3)=8/9. 相似文献
4.
Ageing characteristics of the metastable bcc γ-phase in U–9 wt.% Mo alloy, a candidate for high uranium density nuclear fuel for research and test reactors, have been investigated in this study. Analyses of the aged microstructures, employing X-ray diffraction and various microscopy techniques, revealed the decomposition mechanism of the metastable γ-phase to the stable α-U and γ′ (U2Mo) phases. A discontinuous precipitation reaction, leading to the generation of partially transformed cellular colonies with lamellae comprising of either the α-phase or the γ′-phase in γ-phase matrix, was found to be operative. The in situ transformation of γ interlamellar regions to the γ′-phase was noticed occasionally within the γ + α lamellar colonies. Thermodynamic analysis of the U–Mo system, using free energy–composition diagrams, could associate the observed attributes of the decomposition of γ-phase to the extent of Mo segregation and the chemical driving force required for the nucleation of α- and γ′-phases in the γ-matrix. 相似文献
5.
6.
本文研究了在-170℃到+20℃温度范围内,Sb-Cs光阶极的光效应对温度的依赖关系。在极限波长附近,当温度下降时,发现灵敏度单纯地下降。在短波的地方,灵敏度在一个宽的温度范围内与温度无关;只有到极低温度时,灵敏度才很快下降。 相似文献
7.
The concept of a localk-coloring of a graphG is introduced and the corresponding localk-Ramsey numberr
loc
k
(G) is considered. A localk-coloring ofG is a coloring of its edges in such a way that the edges incident to any vertex ofG are colored with at mostk colors. The numberr
loc
k
(G) is the minimumm for whichK
m
contains a monochromatic copy ofG for every localk-coloring ofK
m
. The numberr
loc
k
(G) is a natural generalization of the usual Ramsey numberr
k
(G) defined for usualk-colorings. The results reflect the relationship betweenr
k
(G) andr
loc
k
(G) for certain classes of graphs.This research was done while under an IREX grant. 相似文献
8.
G. Molnár ZS. Révay Á. Veres A. Simonits H. Rausch 《Journal of Radioanalytical and Nuclear Chemistry》1993,167(1):133-137
The restart of the recently upgraded research reactor in Budapest is foreseen at the end of this year. A number of fast, thermal and cold neutron beams will serve for research, industrial and educational activities. One of the cold neutron guide end positions will be utilized for neutron capture prompt gamma-ray activation analysis (PGAA). Further development of the PGAA method as well as new applications in environmental research, biology and medicine are planned. 相似文献
9.
OG Khvostenko ZS Yarullina NM Shishlov VE Rusin 《Rapid communications in mass spectrometry : RCM》1999,13(12):1091-1097
A correlation between the energies of electronic singlet transitions in benzodiazepines and their biological activity, which was revealed earlier by means of negative ion mass spectrometry with resonance electron capture, has been verified with a UV absorption spectroscopy investigation. Also, it has been noted that the energies of electronic singlet transitions in benzodiazepines are close in value to the ionization energies of atoms Cs, Rb, K, Na, Li and Tl, the cations of which are known to play an important role in nerve cell excitation processes. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
10.
Saify ZS Nisa M Azhar KF Azim MK Rasheed H Mushtaq N Arain MA Haider S Khanum M Ahmed W 《Natural product research》2011,25(20):1965-1968
Piperidine derivatives are reported to exhibit a variety of pharmacological activities. In this article, synthesis and aspartic protease inhibitory activity of three nitrophenacyl derivatives of N-methyl-4-hydroxy piperidine are reported. Enzyme assays showed that the attachment of a nitro group in the benzene ring plays an important role in the inhibition of plasmepsin-II of Plasmodium falciparum. The compound 1-methyl-1-(4'-nitrophenacyl)-4-hydroxypiperidinium bromide (3), consisting of a nitro group at the para position, was the most active at the concentration of 1.0?μM. The activity of the compounds was evaluated through the observed orientation and diagrammatic representation of nitrophenacyl derivatives of 4-hydroxy piperidine. 相似文献