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71.
Familiarity with the diagnostic parameters of viral hepatitis is imperative in the liver transplantation arena. Chronic viral hepatitis B and C are among the most common categories of end-stage liver disease. The preoperative diagnosis, determination of recurrent infection, and the assessment of antiviral therapeutic efficacy are dependent on appropriate virological testing. Furthermore, liver transplant personnel are at a high risk for parenterally transmitted viral hepatitis infection. Knowledge and understanding of the serological patterns of acute and chronic viral hepatitis, as well as recognition of the immune status for one or more of these viruses, will facilitate prevention and treatment of viral hepatitis for these health care providers.  相似文献   
72.
We evaluated the role of intravascular ultrasound (IVUS) in 16 patients with unprotected left main coronary artery (LMCA) stenting compared with 80 patients with other (non-LMCA) native coronary artery stenting and found that (1) additional high-pressure or larger size balloon dilations were more frequently performed in LMCA stenting than in non-LMCA stenting (p <0.05) and (2) after IVUS-guided stent implantation, minimum lumen area was > or = 9 mm2 in 88% of patients who underwent LMCA stenting and in 19% of those who underwent non-LMCA stenting (p <0.001). IVUS guidance may be a more important adjunctive imaging modality in the stenting of unprotected LMCA stenoses than in stenting of non-LMCA stenoses.  相似文献   
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Intraphase redox kinetics were monitored across the wüstite, Fe1–xO, phase of the iron-oxygen system in CO2-CO and CO2-CO-Ar mixtures at 1062 and 1106° C. Kinetic data expressed in terms of the chemical diffusion coefficient and the equilibration time as a function of composition strongly indicated the importance of a reaction at the gas-oxide interface in the overall reequilibration of a specimen. Both the chemical diffusion coefficient and the equilibration time were found to be inversely proportional to the deviation from stoichiometry. Surface rate constants calculated from initial linear oxidation data were found to decrease as the deviation from stoichiometry increased.  相似文献   
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The interaction of single wall carbon nanotubes (SWNT) with an aqueous solution of the fully sulfonated polyaniline poly(2-methoxyaniline-5-sulfonic acid) (PMAS) and (+)-1-phenylethylamine (PhEA) has been investigated using spectroscopic methods. UV-vis spectral measurements show that the PMAS backbone undergoes conformational changes upon interaction with both SWNT and PhEA. Partial intercalation of PMAS into SWNTbundles was confirmed by Raman spectroscopy and electron microscopy.  相似文献   
78.
Beginning with a model of social perception in which the perceiver is assumed to operate according to the conventional canons of statistical inference, it was hypothesized that trait judgments of groups of individuals represented by facial photographs would match the mean values of these photographs judged individually and that confidence and the amount of information required before a judgment is reported will vary inversely with the variance in the set of photographs comprising the group, and directly with the significance of the judgment for the judge. Using different procedures and measures of the dependent variables, 2 experiments were performed which agreed in supporting the hypotheses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Two-terminal devices which exhibit a type-S (current-controlled) or type-N (voltage-controlled) negative differential resistance can be built using only two bipolar transistors and linear positive resistors without any internal biasing power supply. Two general algorithms are presented in this paper for systematically generating all such devices. Hundreds of negative resistance devices have been derived to date using these algorithms and a selection of these circuits is presented in this paper along with their computer-simulated v-i curves. Laboratory measurements of a few sample circuits agree remarkably well with the computer-simulated results.  相似文献   
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