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91.
92.
Zsuzsa M. Jászay Truong Son Pham Katalin Gönczi Imre Petneházy László Tőke 《合成通讯》2013,43(11):1574-1579
A simple and efficient solid/liquid phase-transfer catalytic diazo transfer reaction for the synthesis of diazocarbonyl, diazophosphonyl, and diazophosphinyl compounds is reported. 相似文献
93.
94.
Tyihák Ernő Móricz Ágnes M. Ott Péter G. Kátay György Király-Véghely Zsuzsa 《平面色谱法杂志一现代薄层色谱法》2005,18(1):67-72
JPC – Journal of Planar Chromatography – Modern TLC - New results with BioArena as a complex separation and detection (evaluation) system support earlier observations that formaldehyde... 相似文献
95.
The small signal gain distortions in the field of a Gaussian pump beam were investigated theoretically and experimentally in a Λ-type quantum system depending on the size and power of the pump beam. The strong pump beam induces a change of refraction index of a methanol model material, depending on the frequency of the signal. It leads to a nonlinear active waveguiding effect causing distortion (narrowing and shift) of the signal line shape. In case of Stark splitting, the induced nonlinear active waveguiding effect manifests itself in the disappearance of the line split, for narrow pump beams. Collision induced frequency shift of the signal line depending on the pressure of the methanol gas was observed. 相似文献
96.
Summary Dicarhonyrhodium(I) complexes of eleven amino acids were prepared from [AcORh(COD)]2 and the appropriate amino acid by carboxylato ligand exchange followed by treatment with CO. All complexes are light coloured substances of composition (XY)Rh(CO)2 (where XYH = amino acid) with square planar geometry andcis-carbonyl ligands, The compounds are transformed by IICI into deep coloured hydrochlorides with more complex structures.COD - 1.5-cycloocladiene. 相似文献
97.
Much is known about the genes and proteins controlling the cell cycle of fission yeast. Can these molecular components be spun together into a consistent mechanism that accounts for the observed behavior of growth and division in fission yeast cells? To answer this question, we propose a mechanism for the control system, convert it into a set of 14 differential and algebraic equations, study these equations by numerical simulation and bifurcation theory, and compare our results to the physiology of wild-type and mutant cells. In wild-type cells, progress through the cell cycle (G1-->S-->G2-->M) is related to cyclic progression around a hysteresis loop, driven by cell growth and chromosome alignment on the metaphase plate. However, the control system operates much differently in double-mutant cells, wee1(-) cdc25Delta, which are defective in progress through the latter half of the cell cycle (G2 and M phases). These cells exhibit "quantized" cycles (interdivision times clustering around 90, 160, and 230 min). We show that these quantized cycles are associated with a supercritical Hopf bifurcation in the mechanism, when the wee1 and cdc25 genes are disabled. (c) 2001 American Institute of Physics. 相似文献
98.
Tünde Molnár Árpád Dobolyi Gabriella Nyitrai Péter Barabás László Héja Zsuzsa Emri Miklós Palkovits Julianna Kardos 《BMC neuroscience》2011,12(1):1-17
Background
Late cerebral ischemia carries high morbidity and mortality after subarachnoid hemorrhage (SAH) due to reduced cerebral blood flow (CBF) and the subsequent cerebral ischemia which is associated with upregulation of contractile receptors in the vascular smooth muscle cells (SMC) via activation of mitogen-activated protein kinase (MAPK) of the extracellular signal-regulated kinase (ERK)1/2 signal pathway. We hypothesize that SAH initiates cerebrovascular ERK1/2 activation, resulting in receptor upregulation. The raf inhibitor will inhibit the molecular events upstream ERK1/2 and may provide a therapeutic window for treatment of cerebral ischemia after SAH.Results
Here we demonstrate that SAH increases the phosphorylation level of ERK1/2 in cerebral vessels and reduces the neurology score in rats in additional with the CBF measured by an autoradiographic method. The intracisternal administration of SB-386023-b, a specific inhibitor of raf, given 6 h after SAH, aborts the receptor changes and protects the brain from the development of late cerebral ischemia at 48 h. This is accompanied by reduced phosphorylation of ERK1/2 in cerebrovascular SMC. SAH per se enhances contractile responses to endothelin-1 (ET-1), 5-carboxamidotryptamine (5-CT) and angiotensin II (Ang II), upregulates ETB, 5-HT1B and AT1 receptor mRNA and protein levels. Treatment with SB-386023-b given as late as at 6 h but not at 12 h after the SAH significantly decreased the receptor upregulation, the reduction in CBF and the neurology score.Conclusion
These results provide evidence for a role of the ERK1/2 pathway in regulation of expression of cerebrovascular SMC receptors. It is suggested that raf inhibition may reduce late cerebral ischemia after SAH and provides a realistic time window for therapy. 相似文献99.
Jozsef Bako Marta Szepesi Adrienn J. Veres Csaba Cserhati Zsuzsa M. Borbely Csaba Hegedus Janos Borbely 《Colloid and polymer science》2008,286(3):357-363
Nanocomposite biocompatible hydrogels (NCHG) were synthesised as model systems for in situ cured potentially local drug delivery
devices for curing periodontal infections. The composite consists of the following components: nanoparticles (NPs), matrix
gel, and chlorhexidine (CHX) as antibacterial drug. The NPs were obtained by free radical initiated copolymerization of the
monomers, 2-hydroxyethyl methacrylate (HEMA) and polyethyleneglycol dimethacrylate (PEGDMA), in aqueous solution. The same
monomers were used to prepare crosslinked matrices by photopolymerization. NCHGs were obtained by mixing NPs, monomers, and
drug in an aqueous solution then crosslinked by photopolymerization. Mechanical properties, swelling behavior, and the kinetics
of drug release have been investigated. It was found that compression strength values increased with increasing ratio of the
crosslinker PEGDMA. Incorporation of NPs into the matrix resulted similar compression strength as the matrix hydrogel. The
hydrated NCHGs swelled more slowly but admitted more water. The drug was incorporated in NPs by swelling in CHX aqueous solution
or added to the solution of monomer mixture followed by photopolymerization. Studies of release kinetics revealed that on
average 60% of the loaded drug was released. The most rapid release was observed over a 24 h period for matrix gels with low
crosslinking density. For NCHGs, the release period exceeded 48 h. An unexpected result was observed for NCHGs without drug
in the NPs. In this case, increasing release was observed for the first 24 h. Thereafter, however, the apparent quantity of
detectable drug decreased dramatically. 相似文献
100.
Judit Groska Zsuzsa Molnár Edit Bokori Nóra Vajda 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):707-715
The presence of 89Sr and 90Sr in the biosphere constitutes a biological hazard. There are several analytical methods for the determination of 89Sr and 90Sr. Three analytical methods of various application fields using selective Sr resin for Sr separation and DGA resin for Y
separation and measuring techniques, i.e. liquid scintillation spectrometry and Cerenkov counting are discussed in the paper.
The calculation techniques are compared in the aspects such as trueness and accuracy of the results and the limit of detection.
Uncertainties and detection limits are calculated using the spreadsheet method. 相似文献