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1.
We describe the results of functional studies on DNA clones encoding functional bradykinin receptors derived from human, rat, and mouse sources and including both genomic and complementary DNA clones. In both the Xenopus oocyte and the COS cell expression systems, the receptors from human and rat showed the pharmacological properties of B2 receptors, but receptors from mouse displayed both B1- and B2-like pharmacological properties. We further investigated the molecular relationship between the B1 and B2 receptor subtypes expressed by a human fibroblast cell line, and we demonstrate that these two receptor subtypes are encoded by distinct mRNA species.  相似文献   
2.
BACKGROUND/AIMS: Chronic graft hepatitis occurs in 20-30% adults after liver transplantation but the prevalence and causes in children are not known. In adults, hepatitis C virus infection is prevalent prior to transplantation and recurrent infection is a frequent cause of graft dysfunction. The significance of the recently described hepatitis G virus infection remains unproven. The aim of this study was to examine the role of hepatitis C virus and hepatitis G virus infection in chronic graft hepatitis after paediatric liver transplantation. METHODS: The prevalence of graft hepatitis and the role of hepatitis C virus and hepatitis G virus infections in 80 children after liver transplantation have been studied, with a median follow up of 4.4 years (range 0.4 to 10.7), and the persistence of hepatitis G infection in the presence of immunosuppression has been determined. RESULTS: Chronic graft hepatitis was diagnosed in 19/80 (24%) children and was most frequently seen in children transplanted for cryptogenic cirrhosis (71%). There was no significant difference in the prevalence of chronic hepatitis in those transplanted before or after donor anti-HCV screening. Hepatitis C infection occurred in three children transplanted prior to donor screening but in only one was associated with chronic hepatitis. Hepatitis G infection was found in 22/79 (28%) transplant recipients but was not associated with graft hepatitis. In 17/21 children hepatitis G infection persisted for a median of 5.2 years after transplantation. CONCLUSION: Chronic hepatitis occurred in 24% of children after liver transplantation, a similar prevalence to that in adults. Cryptogenic liver disease predisposed to graft hepatitis, but neither hepatitis C nor hepatitis G infection was associated. Hepatitis G virus caused a frequent and usually persistent infection after transplantation.  相似文献   
3.
Neural Computing and Applications - In the medical imaging domain, nonlinear warping has enabled pixel-by-pixel mapping of one image dataset to a reference dataset. This co-registration of data...  相似文献   
4.
Diode-Pumped Solid-State Lasers for Inertial Fusion Energy   总被引:5,自引:0,他引:5  
We have begun building the Mercury laser system as the first in a series of new generation diode-pumped solid-state lasers for inertial fusion research. Mercury will integrate three key technologies: diodes, crystals, and gas cooling, within a unique laser architecture that is scalable to kilojoule and megajoule energy levels for fusion energy applications. The primary near-term performance goals include 10% electrical efficiencies at 10 Hz and 100J with a 2–10 ns pulse length at 1.047 m wavelength. When completed, Mercury will allow rep-rated target experiments with multiple chambers for high energy density physics research.  相似文献   
5.
Plant species discrimination using remote sensing is generally limited by the similarity of their reflectance spectra in the visible, NIR and SWIR domains. Laboratory measured emissivity spectra in the mid infrared (MIR; 2.5 μm–6 μm) and the thermal infrared (TIR; 8 μm–14 μm) domain of different plant species, however, reveal significant differences. It is anticipated that with the advances in airborne and space borne hyperspectral thermal sensors, differentiation between plant species may improve. The laboratory emissivity spectra of thirteen common broad leaved species, comprising 3024 spectral bands in the MIR and TIR, were analyzed. For each wavelength the differences between the species were tested for significance using the one way analysis of variance (ANOVA) with the post-hoc Tukey HSD test. The emissivity spectra of the analyzed species were found to be statistically different at various wavebands. Subsequently, six spectral bands were selected (based on the histogram of separable pairs of species for each waveband) to quantify the separability between each species pair based on the Jefferies Matusita (JM) distance. Out of 78 combinations, 76 pairs had a significantly different JM distance. This means that careful selection of hyperspectral bands in the MIR and TIR (2.5 μm–14 μm) results in reliable species discrimination.  相似文献   
6.
Recent clinical research suggests that several self-report behavioral economic measures of relative reinforcing efficacy (RRE) may show utility as indices of substance abuse problem severity. The goal of the present study was to evaluate the reliability and validity of the Alcohol Purchase Task (APT), a RRE measure that uses hypothetical choices regarding alcohol purchases at varying prices (demand curves) to generate several indices of alcohol-related reinforcement. Participants were 38 college students who reported recent alcohol consumption. Both the raw alcohol purchase/consumption values and several of the computed reinforcement parameters (intensity & Omax) showed good to excellent 2-week test–retest reliability. Reinforcement parameters derived from both a linear-elasticity (Hursh, Raslear, Bauman, & Black, 1989) and an exponential (Hursh & Silberberg, 2008) demand curve equation were generally less reliable, despite the fact that both equations provided a good fit to participants’ reported consumption data. The APT measures of demand intensity (number of drinks consumed when price = 0), Omax (maximum expenditure), and elasticity (α) were correlated with weekly drinking, alcohol-related problems, and other self-report RRE measures (relative discretionary monetary expenditures toward alcohol and/or relative substance-related activity participation and enjoyment). Demand intensity was uniquely associated with problem drinking in a regression model that controlled for weekly consumption. These results provide support for the reliability and validity of the RRE indices generated with the APT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
The theory of urethral resistance and the derivation or mural tension have been discussed. A method for the continuous calculation and presentation of these parameters has been described. Urethral resistance and mural tensions are altered by the presence of bladder outflow obstruction and have been shown to return to normality after the obstruction is removed.  相似文献   
8.
The aim of this study was to compare the performance of various narrowband vegetation indices in estimating Leaf Area Index (LAI) of structurally different plant species having different soil backgrounds and leaf optical properties. The study uses a dataset collected during a controlled laboratory experiment. Leaf area indices were destructively acquired for four species with different leaf size and shape. Six widely used vegetation indices were investigated. Narrowband vegetation indices involved all possible two band combinations which were used for calculating RVI, NDVI, PVI, TSAVI and SAVI2. The red edge inflection point (REIP) was computed using three different techniques. Linear regression models as well as an exponential model were used to establish relationships. REIP determined using any of the three methods was generally not sensitive to variations in LAI (R 2 < 0.1). However, LAI was estimated with reasonable accuracy from red/near-infrared based narrowband indices. We observed a significant relationship between LAI and SAVI2 (R 2 = 0.77, RMSE = 0.59 (cross validated)). Our results confirmed that bands from the SWIR region contain relevant information for LAI estimation. The study verified that within the range of LAI studied (0.3 ≤ LAI ≤ 6.1), linear relationships exist between LAI and the selected narrowband indices.  相似文献   
9.
10.
Abstract

One result of this research showed the relationship of the crack propagation into the burden as decoupling increased from 1 to 3. The resulting data indicated that the explosive generated gas pressure was the dominate parameter for breaking rock in confined boreholes. The shock energy did not have time to play an effective role in burden breakage, for by the time the stress wave returned to the face, the burden had broken under pressure.  相似文献   
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