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111.
Patterson P 《OR manager》2011,27(11):1, 9-1,10
112.
Ji-Yao Li Biaoxin Chai Weizhen Zhang Xiaobin Wu Chao Zhang Danielle Fritze Zefeng Xia Cam Patterson Michael W Mulholland 《BMC neuroscience》2011,12(1):1-10
Background
Cigarette smoking enhances the risk of stroke. However, the underlying molecular mechanisms are largely unknown. The present study established an in vivo rat secondhand cigarette smoking (SHS) model and examined the hypothesis that SHS upregulates endothelin receptors with increased cerebrovascular contraction via the Raf/extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinases (MAPK) pathway.Results
Rats were exposed to SHS for up to 8 weeks. The cerebral artery vasoconstriction was recorded by a sensitive myograph. The mRNA and protein expressions for endothelin receptors in cerebral arteries were studied by real-time PCR and Western blot. Compared to fresh air exposed rats, cerebral arteries from SHS rats exhibited stronger contractile responses (P < 0.05) mediated by endothelin type A (ETA) receptors. The expressions of mRNA and protein for ETA receptors in the cerebral arteries from SHS rats were higher (P < 0.05) than that in control. SHS did not affect endothelin type B (ETB) receptor-mediated contractions, mRNA or protein levels. The results suggest that SHS upregulates ETA, but not ETB receptors in vivo. After SHS exposure, the mRNA levels of Raf-1 and ERK1/2, the protein expression of phosphorylated (p)-Raf-1 and p-ERK1/2 were increased (P < 0.05). Raf-1 inhibitor, GW5074 suppressed the enhanced ETA receptor-mediated contraction, mRNA and protein levels induced by SHS. In addition, GW5074 inhibited the SHS-caused increased mRNA and phosphorylated protein levels of Raf-1 and ERK1/2, suggesting that SHS induces activation of the Raf/ERK/MAPK pathway.Conclusions
SHS upregulates cerebrovascular ETA receptors via the Raf/ERK/MAPK pathway, which provides novel understanding of mechanisms involved in SHS-associated stroke. 相似文献113.
A method is presented that allows real-time three-dimensional displacement maps to be obtained for deformable objects using a single color camera and a color fringe projector. The acquired images have speckle and fringe information embedded in them, which are separated using the R, G, and B color signals from a color CCD camera to permit the independent use of a two-dimensional digital image correlation to obtain the x- and y-direction displacements and fringe projection to obtain the displacement in the z direction. 相似文献
114.
In this Letter we extend our investigations on noise-assisted storage devices through the experimental study of a loop composed of a single Schmitt trigger and an element that introduces a finite delay. We show that such a system allows the storage of several bits and does so more efficiently for an intermediate range of noise intensities. Finally, we study the probability of erroneous information retrieval as a function of elapsed time and show a way for predicting device performance independently of the number of stored bits. 相似文献
115.
A rational decision making model for experimental mechanics 总被引:1,自引:0,他引:1
Experimental Techniques - A rational decision-making model with conjunctive and compensatory rules has been proposed and demonstrated for use in experimental mechanics. The model contains a logical... 相似文献
116.
117.
Richard A. Patterson 《Fiber and Integrated Optics》1990,9(2):131-142
Splicing of optical fibers will be a major determining factor in the technical and economic success of fiber networks built in the 1990s. Needs, requirements, and specifications are now being proposed for the splicing systems to be used in these future networks. Two basic objectives for the splicing system of the 1990s can be defined from all the study and analysis that has been done thus far. Simply stated, the most widely accepted splicing system for the future will be the one that provides the highest performance at the lowest installed cost.
A new splicing system has been developed that addresses and meets many of the requirements that have been proposed. This system provides high splice performance and at the same time is very easy and fast to use. It also has low-cost assembly tooling and has been exhaustively tested to ensure conformance with proposed performance specifications. 相似文献
A new splicing system has been developed that addresses and meets many of the requirements that have been proposed. This system provides high splice performance and at the same time is very easy and fast to use. It also has low-cost assembly tooling and has been exhaustively tested to ensure conformance with proposed performance specifications. 相似文献
118.
119.
Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Zhang K Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Naik P Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Pivarski J 《Physical review letters》2007,99(19):191801
Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions. 相似文献
120.