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1.
2.
The galanin-receptor ligand M40 [galanin-(1-12)-Pro3-(Ala-Leu)2-Ala amide] binds with high affinity to [mono[125I]iodo-Tyr26]galanin-binding sites in hippocampal, hypothalamic, and spinal cord membranes and in membranes from Rin m5F rat insulinoma cells (IC50 = 3-15 nM). Receptor autoradiographic studies show that M40 (1 microM) displaces [mono[125I]iodo-Tyr26]galanin from binding sites in the hippocampus, hypothalamus, and spinal cord. In the brain, M40 acts as a potent galanin-receptor antagonist: M40, in doses comparable to that of galanin, antagonizes the stimulatory effects of galanin on feeding, and it blocks the galaninergic inhibition of the scopolamine-induced acetylcholine release in the ventral hippocampus in vivo. In contrast, M40 completely fails to antagonize both the galanin-mediated inhibition of the glucose-induced insulin release in isolated mouse pancreatic islets and the inhibitory effects of galanin on the forskolin-stimulated accumulation of 3',5'-cAMP in Rin m5F cells; instead M40 is a weak agonist at the galanin receptors in these two systems. M40 acts as a weak antagonist of galanin in the spinal flexor reflex model. These results suggest that at least two subtypes of the galanin receptor may exist. Hypothalamic and hippocampal galanin receptors represent a putative central galanin-receptor subtype (GL-1-receptor) that is blocked by M40. The pancreatic galanin receptor may represent another subtype (GL-2-receptor) that recognizes M40, but as a weak agonist. The galanin receptors in the spinal cord occupy an intermediate position between these two putative subtypes.  相似文献   
3.
From 1988 to 1995, 96 patients (161 feet) underwent a modified Mitchell distal metatarsal osteotomy performed for mild-to-moderate hallux valgus. On AP x-rays of the standing foot, the average intermetatarsal angle was corrected from 15 degrees to 9 degrees, and the first metatarsophalangeal angles were corrected from an average of 41 degrees to 15 degrees. Criteria for evaluation of clinical results included relief of pain, appearance of foot, and shoe wear. After an average follow-up of 38 months, the overall satisfaction rate was 92.5%. Complications included 13 pin tract infections, two delayed unions, and two correction losses. The most common late sequela was transfer metatarsalgia of the lesser toes, which occurred in 20 feet (12.4%), leading to some dissatisfaction. The Mitchell osteotomy can be used on cases with less than 20 degrees of intermetatarsal angle, offering a stable construct with easy postoperative care.  相似文献   
4.
根据SAR(Synthetic Aperture Radar)影像相干噪声的特点,对现在广泛应用的各种抑制噪声的滤波方法如均值滤波、Frost滤波、增强型Lee滤波、Lee滤波、中值滤波等进行分析,并提出适合本研究区影像的基于小波变换的分量滤波处理去噪方法,利用均值、标准差、平滑指数、PM值、信息熵和平均梯度等评价指标对各种滤波去噪后的影像质量进行评价,并对去噪效果进行对比分析,证明本文所采用的滤波方法对SAR影像噪声有很好的抑制作用,并且较好的保存了图像纹理信息。  相似文献   
5.
Loring JS  Land DP 《Applied optics》1998,37(16):3515-3526
We investigate the feasibility of overlayer attenuated-total-reflectance (O-ATR) infrared spectroscopy as a surface analytical tool for studying reactions and molecular properties of adsorbates at surfaces exposed to aqueous nonelectrolyte solutions. Through modeling an O-ATR system by assuming it to comprise three, four, or n phases of homogeneous refractive index, one can use an electric-field analysis to determine how the parameters of adsorption free energy, overlayer thickness, initial angle of incidence, and internal-reflection element refractive-index influence solvent-subtracted O-ATR infrared-absorption spectra. The theory behind such an analysis is explained, and the results of its application are presented for hypothetical O-ATR systems consisting of either a zinc selenide or a germanium internal-reflection element, an iron or hematite overlayer, an adsorbate layer, and a solution of methylene chloride in water.  相似文献   
6.
Land PE  Haigh JD 《Applied optics》1996,35(27):5443-5451
A modular atmospheric correction algorithm is proposed that uses atmospheric and water contents models to predict the visible and near-infrared reflectances observed by a satellite over water. These predicted values are compared with the satellite reflectances at each pixel, and the model parameters changed iteratively with an error minimization algorithm. The default atmospheric model uses single-scattering theory with a correction for multiple scattering based on lookup tables. With this model we used parameters of the proportions of three tropospheric aerosol types. For the default water content model we need the parameters of the concentrations of chlorophyll, inorganic sediment, and gelbstoff. The diffuse attenuation and backscatter coefficients attributed to these constituents are calculated and used to derive the water-leaving reflectance. Products include water-leaving reflectance, concentrations of water constituents, and aerosol optical depth and type. We demonstrate the application of the method to sea-viewing wide field-of-view sensor by using model data.  相似文献   
7.
In this work, we report synthesis and characterization of the new La2SrCo2FeO9 triple perovskite material. The samples were produced by the solid-state reaction method. The analyses of the XRD patterns were made by Rietveld refinement through the GSAS code. The results reveal that the material crystallizes in an orthorhombic complex perovskite, space group Immm (#71) with lattice parameters a=5.4314(3) ?, b=5.4583(3) ? and c=7.7018(2) ?. SEM micrographs evidence a strongly diffused granular morphology with mean grain size of 2 μm and the EDX spectra show that the chemical composition of samples are in good agreement with the nominal values of the stoichiometric formula. 57Fe Mössbauer spectroscopy recorded at 300 K reveals two sites in concordance with the X-ray diffraction measurements, and its valence state is +3, as determined from the isomer shift found. At 4.2 K magnetic ordering with canting of the Fe moments is found. Measurements of the magnetization as a function of temperature permitted us to determine the ferromagnetic characteristic of material with an effective magnetic moment of 9.7μ B.  相似文献   
8.
Covering objects with masking tapes is a common process for surface protection in processes like spray painting, plasma spraying, shot peening, etc. Manual taping is tedious and takes a lot of effort of the workers. The taping process is a special process which requires correct surface covering strategy and proper attachment of the masking tape for an efficient surface protection. We have introduced an automatic robot taping system consisting of a robot manipulator, a rotating platform, a 3D scanner and specially designed taping end-effectors. This paper mainly talks about the surface covering strategies for different classes of geometries. The methods and corresponding taping tools are introduced for taping of following classes of surfaces: Cylindrical/extended surfaces, freeform surfaces with no grooves, surfaces with grooves, and rotational symmetrical surfaces. A collision avoidance algorithm is introduced for the robot taping manipulation. With further improvements on segmenting surfaces of taping parts and tape cutting mechanisms, such taping solution with the taping tool and the taping methodology can be combined as a very useful and practical taping package to assist humans in this tedious and time costly work.  相似文献   
9.
麦胚中总黄酮的提取新工艺研究   总被引:2,自引:0,他引:2  
研究了利用乙醇提取麦胚总黄酮及微波辅助萃取的方法提高麦胚黄酮的提取率。  相似文献   
10.
各省、自治区、直辖市及计划单列市、新疆生产建设兵团发展改革委、经贸委(经委)、国土资源厅(国土资源局),中国人民银行上海总部、各分行、营业管理部、各省会(首府)城市中心支行,大连、青岛、宁波、厦门、深圳市中心支行,国家开发银行、中国工商银行、中国农业银行、中国银行、中国建设银行:  相似文献   
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