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The purpose of this study was to characterize quality of care problems among Medicare and Medicaid inpatients in New York State. The patients selected for this study comprised 1991 and 1992 Medicare and all 1992 Medicaid inpatients in whom quality of care problems with actual or potential adverse effects were found. The patients in this study were drawn from public, proprietary, voluntary and teaching hospitals. A total of 1000 quality of care problems with either actual or potential adverse effects were found in 706 Medicare patients. Two hundred and seventy-five (275) quality of care problems with actual or potential adverse effects were found in 154 Medicaid patients. Premature death occurred in 53 (7.4%) of the 706 Medicare and in 42 (27.2%) of the 154 Medicaid patients. Treatment problems and monitoring failures accounted for the majority of quality of care problems with actual or potential adverse effects for both Medicare (63.0%) and Medicaid (75.7%) patients. Among Medicare patients, the treatment of infections and antibiotic use, fluid and electrolyte management, and inappropriate drug use were among the leading causes of quality of care problems. Attending physicians were associated with the majority of Medicare quality of care problems while house staff and attending physicians were associated with the majority of those among Medicaid patients. The results of this study indicate that there are several leading causes of quality of care problems among Medicare and Medicaid patients. Treatment problems and monitoring failures together comprise the majority of such problems. Among Medicare patients, it was found that most quality of care problems were associated with the treatment of infections and antibiotic use, fluid and electrolyte management, and inappropriate drug use. Most quality of care problems among Medicaid patients were associated with these categories as well as with labor and delivery problems, and poor discharge planning. The results of this study reflect the peer-review process in which providers are given an opportunity to respond to physician-reviewer decisions about the presence of actual or potential adverse effects. Such a process, which permits the presentation of additional data and information by providers, produces fewer final adverse outcome determinations than a process uniquely based on chart review. The quality of care problems observed in this study are amenable to focused educational interventions. Such remedial interventions could yield significant improvements in the quality of care for all patients.  相似文献   
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1. The spontaneously hypertensive rat (SHR) exhibits a lower bodyweight in utero and an exaggerated salt appetite post partum. To determine whether salt appetite is affected by the perinatal environment, we measured the salt appetite of embryo-cross-transferred SHR and Wistar Kyoto (WKY) rats at maturity. 2. One-cell embryos were collected from the oviducts of donor rats and transferred into the oviducts of recipients through the infundibulum. The salt appetite of the resultant female offspring for 0.10 and 0.15 mol/L saline was measured at 20-30 weeks of age. 3. Salt intake of SHR gestated in WKY rats was significantly lower than that of SHR gestated in SHR, while that of WKY rats gestated in SHR was higher than that of WKY rats gestated in WKY rats. 4. Therefore, some maternal factor plays a role in the development of the exaggerated salt appetite of the SHR. This factor is also able to affect the later salt appetite of WKY rat offspring born to SHR surrogates.  相似文献   
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Conventional access methods cannot be effectively used in large Scientific/Statistical Database (SSDB) applications. A file structure (called bit transposed file (BTF)) is proposed which offers several attractive features that are better suited for the special characteristics that SSDBs exhibit. This file structure is an extreme version of the (attribute) transposed file. The data are stored by vertical bit partitions. The bit patterns of attributes are assigned using one of several data encoding methods. Each of these encoding methods is appropriate for different query types. The bit partitions can also be compressed using a version of the run length encoding scheme. Efficient operators on compressed bit vectors have been developed and form the basis of a query language. Because of the simplicity of the file structure and query language, optimization problems for database design, query evaluation, and common subexpression removal can be formalized and efficient exact solution or near optimal solution can be achieved. In addition to selective power with low overheads for SSDBs, the BTF is also amenable to special parallel hardware. Results from experiments with the file structure suggest that this approach may be a reasonable alternative file structure for large SSDBs.  相似文献   
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Isao Mochida  Harry Marsh  Alan Grint 《Fuel》1979,58(11):803-808
In industrial situations, coals interact with solvents or additives to produce liquid fuels, solvent-refined coal, coal extract and metallurgical coke. In these processes there occurs a wide variation in effects or modifications of the coal by these additives. This paper describes the modifications which can occur, using a wide range of rank of coal, when these coals interact and are co-carbonized with a wide range of additives of different chemical properties. The optical texture of the resultant cokes is given special attention. The objective of the paper is to summarize the current state of knowledge of the mechanisms of these interactions. Possible mechanisms of interactions are summarized, kinetic and chemical structural aspects of reactions are outlined, the importance is mentioned of the formation of liquid phases enabling anisotropic optical textures in modified cokes to be created, and the industrial relevance of its possible development is discussed.  相似文献   
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The hydrolytic degradation of gel microspheres based on calcium cross-linked phosphazene polyelectrolytes, poly[di(carboxylatophenoxy)phosphazene] (PCPP) and poly[(carboxylatophenoxy) (glycinato)phosphazene] (PCGPP), was investigated. These microspheres are of importance as carriers in protein and cell encapsulation. Both PCPP and PCGPP ionotropic polyphosphazene hydrogels are degradable in an aqueous environment (pH 7.4, 37°C). The degradation rates can be increased by incorporation of hydrolysis sensitive glycinato groups as the pendant structures in the polymer (PCGPP). Hydrolysis of these polymer hydrogels led to low molecular weight (<1,000 Da) products. The erosion and molecular weight profiles varied also according to the molecular weight of the polyphosphazene constituting the gel beads. Another approach to affect the degradation rates consists of coating microspheres with poly-L -lysine. Ionotropic polyphosphazene hydrogels have potential as biodegradable devices for controlled drug delivery systems. © 1994 John Wiley & Sons, Inc.  相似文献   
29.
This study examines further the phenomena of the modification of coal carbonizations by organic additives. Anthracene, pyrene and chrysene modify the carbonization in a closed system of coking coals as observed from increases in the size of optical textures of resultant cokes. Weakly caking coals are unaffected. Chrysene is the most efficient modifier probably because of its lowest calculated free valence. The co-additives tetralin and hydrogenated anthracene oil further enhance the modification processes so obviating the necessity to use hydrogenated additives. Co-carbonizations of oxidized coking and caking coals with decacyclene are effective in removing the effects of mild oxidation. Increased rates of carbonization enhance the sizes of optical textures of resultant cokes.  相似文献   
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PERIODIC CORRELATION IN STRATOSPHERIC OZONE DATA   总被引:1,自引:0,他引:1  
Abstract. A 50-year time series of monthly stratospheric ozone readings from Arosa, Switzerland, is analyzed. The time series exhibits the properties of a periodically correlated (PC) random sequence with annual periodicities. Spectral properties of PC random sequences are reviewed and a test to detect periodic correlation is presented. An autoregressive moving-average (ARMA) model with periodically varying coefficients (PARMA) is fitted to the data in two stages. First, a periodic autoregressive model is fitted to the data. This fit yields residuals that are stationary but non-white. Next, a stationary ARMA model is fitted to the residuals and the two models are combined to produce a larger model for the data. The combined model is shown to be a PARMA model and yields residuals that have the correlation properties of white noise.  相似文献   
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