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961.
962.
In retinal synapses between cones and luminosity type horizontal cells (LHC), it was previously found in this laboratory that
repetitive red flashes progressively strengthened the LHC’s response to red flash, whereas weakened the LHC’s response to
green flash; repetitive green flash remarkably depressed the LHC’s red response, but caused little changes in the cell’s green
response. However, the detailed mechanisms underlying these phenomena are not entirely clear. In the present study, based
on an ion-channel model described mainly in the form of Hodgkin–Huxley equations, possible mechanisms of the short-term synaptic
modification are investigated. The simulation results suggest that: (1) the auto-enhancement effect might be induced by the
Ca2+-dependent process on the post-synaptic AMPA receptors, which could lead to changes of the ionic channel’s properties; (2)
the asymmetric response to red- and green-flashes and the mutual-chromatic suppression effects might be attributed to the
regulatory effects on the presynaptic glutamate release. 相似文献
963.
964.
Mitochondrial rRNA and tRNA and hearing function 总被引:2,自引:0,他引:2
965.
966.
HIV Vaccine-Challenges and Opportunities 总被引:1,自引:0,他引:1
Xin MA Cai-jun SUN Feng LI Ling CHEN 《Virologica Sinica》2007,22(6):486-492
The need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of an efficacious HIV/AIDS vaccine proves an enormous scientific challenge. This article reviews the neutralizing antibody problem,elusive immune protection,im-munogen design,pre-existing anti-vector immunity and design of phase 3 vaccine trials and the challenges and opportunities in development of HIV/AIDS vaccine are discussed. 相似文献
967.
Martin MW Newcomb J Nunes JJ Bemis JE McGowan DC White RD Buchanan JL DiMauro EF Boucher C Faust T Hsieh F Huang X Lee JH Schneider S Turci SM Zhu X 《Bioorganic & medicinal chemistry letters》2007,17(8):2299-2304
2,3-Diarylfuro[2,3-b]pyridine-4-amines are a novel class of potent and selective inhibitors of Lck. The discovery, synthesis, and structure activity relationships of this series of inhibitors are reported. The most promising compounds were also profiled to deduce their pharmacokinetic properties. 相似文献
968.
Yang SM Malaviya R Wilson LJ Argentieri R Chen X Yang C Wang B Cavender D Murray WV 《Bioorganic & medicinal chemistry letters》2007,17(2):326-331
Simplification of bottom ring and regioselective functionalization of the indolocarbazole unit of staurosporine (2) are described. The modification led to a new series of simplified staurosporine analogs, which exhibited significant inhibitory activity against Janus kinase 3 (JAK3). The structure-activity relationships (SAR) are discussed and a proposed binding model is also highlighted. 相似文献
969.
In this paper, a new chemiluminescent plant tissue-based biosensor for diamine detection was presented by employing sequential injection analysis (SIA), which facilitates precise fluidic handling and lower consumption of sample and reagents. Pea-seedling tissue acted as the molecular recognition element and was packed in a mini-PTFE column and further incorporated in the SIA system. The analysis of diamines, such as putrescine and cadaverine, is based on an enzymatic conversion which takes place in the plant tissue column to produce hydrogen peroxide. The formed hydrogen peroxide was detected by a chemiluminescence reaction involving luminol and Co(2+). Under the optimal conditions, the linear calibration graphs were obtained within 0.2-80 microM (putrescine) and 0.5-100 microM (cadaverine). The detection limits of 0.03 and 0.06 microM were achieved for putrescine and cadaverine, respectively, along with the relative standard deviations of 2.14% and 3.08% (n=11) and a sampling frequency of 40 h(-1). The present biosensor has been used for the analysis of diamine in fish samples with an acceptable accuracy. 相似文献
970.
Lijun Liu Xin Jin Shaoming Yang Zhichun Chen Xianfu Lin 《Biosensors & bioelectronics》2007,22(12):3210
The bilayer of Con A/HRP through the biospecific affinity of concanavalin A (Con A) and glycoprotein horseradish peroxidase (HRP) was prepared on the surface of an Au electrode modified by the precursor film consisted of poly(allylamine hydrochloride) poly(sodium-p-styrene-sulfonate). Atomic force microscopy and electrochemical impedance spectroscopy were adopted to monitor the uniform layer-by-layer assembly of the Con A/HRP bilayers. The amperometric measurement was based on the inhibition of reduced thiols and performed in the presence of the electron mediator hydroquinone in 0.2 M phosphate buffer of pH 6.5 at an applied potential of −0.15 V versus Ag/AgCl. Under the optimal conditions, the biosensor presented a linear response for cysteine from 0.1 to 23.5 μM, with a detection limit of 0.02 μM. The biosensor demonstrated high stability and repeatability. A series of reduced thiols were detected by this inhibition biosensor and oxidized thiols showed no effect on the current response of the biosensor. 相似文献