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31.
With the advent of DRG reimbursement for Medicare patients, hospitals have had to use their case mix data more effectively. This paper describes a method use to develop summary case mix reports using a spreadsheet program. With this approach, the hospital administration could interact more during the development of the summary reports. Once the summary reports are stabilized, they can be put into production on the Hospital's main frame computer.  相似文献   
32.
Transgenic mice expressing chimeric human (alpha1 and alpha2 HLA-A11 domains) and murine (alpha3, transmembrane, and cytoplasmic H-2Kb domains) class I molecules were derived. These mice were used as a model system to study the immunogenicity of human CTL epitopes and also to examine the aspects of Ag processing differences of mice vs man. Immunization of these mice with seven known HLA-A11-restricted CTL epitopes emulsified in IFA resulted in vigorous specific CTL responses. A larger panel of 45 A11-binding peptides was used to examine the relationship between immunogenicity in the HLA-A11/Kb transgenic mice and HLA-A11 binding capacity. Twenty-one of 28 (75%) peptides with high binding affinities (50% inhibitory concentration (IC50), 2-50 nM) and 7 of 13 (54%) intermediate binding peptides (IC50, 50-500 nM range) were immunogenic. In parallel, 19 of these peptides were used for in vitro primary immunizations of PBMC derived from HLA-A11 healthy human donors. It was found that 8 of 8 peptides that were able to elicit CTL in primary human in vitro cultures were also immunogenic in HLA-A11/Kb mice. Finally, HLA-A11/Kb transgenic mice were found to generate an A11/Kb restricted CTL response following immunization with influenza virus A/PR/8/34, suggesting that, at least to some extent, A11 epitopes are generated by transgenic mice as a result of natural in vivo processing and presentation.  相似文献   
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Comments on D. L. Johnson's (see record 1989-29564-001) view of schizophrenia as a brain disease and on H. P. Lefley's (see record 1989-29581-001) view that families have been stigmatized for their role in major mental illness. Based on clinical experience, it is argued that families can indeed be psychogenic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
Many laboratory studies of delayed ettringite formation (DEF) have been conducted on thin mortar bar specimens, heat treated, and then immersed in water. Under these conditions, rapid diffusion of alkali hydroxide into the surrounding water occurs and necessarily reduces the alkali hydroxide concentration of the mortar pore solution. Results reported recently by Famy indicate that the DEF process is triggered as a consequence of such leaching. When it is prevented by immersion into alkali hydroxide solution instead of water DEF expansion is delayed or prevented entirely. Results reported by Zhang indicate that 51-mm mortar cubes behave differently than more leaching-susceptible mortar bars when exposed to the same wet environment. Mortars that show severe DEF as mortar bars remain almost free of DEF symptoms if they are stored as cubes, even after 900 days. Attention is called to the fact that DEF in concrete is found commonly in thick concrete members where the possibility of leaching is remote. For such concrete, the reduction in internal alkali hydroxide concentration that occurs with ASR can substitute for the effect of leaching. It is postulated that without effective reduction of alkali hydroxide concentration by one or the other process, DEF remains latent.  相似文献   
37.
Copper/zinc (Cu/ZnSOD) and manganese (MnSOD) superoxide dismutases which catalyze the dismutation of toxic superoxide anion, O(2-)-, to O2 and H2O2, play a major role in protecting cells from toxicity of oxidative stress. However, cells overexpressing either form of the enzyme show signs of toxicity, suggesting that too much SOD may be injurious to the cell. To elucidate the possible mechanism of this cytotoxicity, the effect of SOD on DNA and RNA strand scission was studied. High purity preparations of Cu/ZnSOD and MnSOD were tested in an in vitro assay in which DNA cleavage was measured by conversion of phage phi X174 supercoiled double-stranded DNA to open circular and linear forms. Both types of SOD were able to induce DNA strand scission generating single- and double-strand breaks in a process that required oxygen and the presence of fully active enzyme. The DNA strand scission could be prevented by specific anti-SOD antibodies added directly or used for immunodepletion of SOD. Requirement for oxygen and the effect of Fe(II) and Fe(III) ions suggest that cleavage of DNA may be in part mediated by hydroxyl radicals formed in Fenton-type reactions where enzyme-bound transition metals serve as a catalyst by first being reduced by superoxide and then oxidized by H2O2. Another mechanism was probably operative in this system, since in the presence of magnesium DNA cleavage by SOD was oxygen independent and not affected by sodium cyanide. It is postulated that SOD, by having a similar structure to the active center of zinc-containing nucleases, is capable of exhibiting non-specific nuclease activity causing hydrolysis of the phosphodiester bonds of DNA and RNA. Both types of SOD were shown to effectively cleave RNA. These findings may help explain the origin of pathology of certain hereditary diseases genetically linked to Cu/ZnSOD gene.  相似文献   
38.
There are significant differences between designing hardware and software for the user interface to computer-based information systems. Formal standards may improve hardware design but may prove ineffective for aiding software design. Our present knowledge supports development of flexible design guidelines for user interface software, but does not justify imposition of standards. Effective application of guidelines will require a process of translation into system-specific design rules, and/or future incorporation into computer-based design algorithms.  相似文献   
39.
Responds to H. G. Furth's (see Pa, Vol 82:21230) comments on S. Guisinger and S. J. Blatt's (see record 1994-25035-001) evolutionary solution to integrate egocentric and sociocentric directions of ontogenetic development. Guisinger and Blatt present supporting (Guisinger) and opposing (Blatt) views on Furth's argument that humans have separate innate schemas for individuation, interpersonal, and wider societal relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
This paper reports on the preparation of novel sol-gel erbium-doped SiO2-based nanocomposites embedded with Nb2O5 nanocrystals fabricated using a bottom-up method and describes their structural, morphological, and luminescence characterization. To prepare the glass ceramics, we synthesized xerogels containing Si/Nb molar ratios of 90:10 up to 50:50 at room temperature, followed by annealing at 900, 1000, or 1100 °C for 10 h. We identified crystallization accompanying host densification in all the nanocomposites with orthorhombic (T-phase) or monoclinic (M-phase) Nb2O5 nanocrystals dispersed in the amorphous SiO2 phase, depending on the niobium content and annealing temperature. A high-intensity broadband emission in the near-infrared region assigned to the 4I13/2 → 4I15/2 transition of the Er3+ ions was registered for all the nanocomposites. The shape and the bandwidth changed with the Nb2O5 crystalline phase, with values achieving up to 81 nm. Er3+ ions were located mainly in Nb2O5-rich regions, and the complex structure of the different Nb2O5 polymorphs accounted for the broadening in the emission spectra. The materials containing the T-phase, displayed higher luminescence intensity, longer 4I13/2 lifetime and broader bandwidth. In conclusion, these nanostructured materials are potential candidates for photonic applications like optical amplifiers and WDM devices operating in the S, C, and L telecommunication bands.  相似文献   
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