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31.
OBJECTIVES: This study was designed to characterize physician practices in the management of congestive heart failure (CHF) and to determine whether these practices vary by specialty and how they relate to guideline recommendations. BACKGROUND: Congestive heart failure is responsible for considerable mortality, morbidity and health care resource utilization. Although there have been important advances in the diagnostic evaluation and treatment of CHF, little information is available on physician practices in this area. METHODS: We surveyed physicians concerning their management of patients with CHF. The results were analyzed in multivariate models to determine the relation of diagnostic and treatment approaches to physician specialty, time since training, board certification and volume of patients with CHF. Surveys were sent to a sample of 2,250 family and general practitioners (FP/GPs), internists and cardiologists. Responses were examined in relation to guidelines issued by the Agency for Health Care Policy and Research that had been released 9 months previously. RESULTS: Significant differences were found between physician groups with regard to each of the major guideline recommendations. For example, routine evaluation of left ventricular function, a point of emphasis in the guideline, is performed by 87% of cardiologists, but by only 77% of internists and 63% of FP/GPs (p < 0.001 between groups). Angiotensin-converting enzyme inhibitors were used by cardiologists, internists and FP/GPs in 80%, 71% and 60% of patients with mild to moderate CHF, respectively (p < 0.001 between groups). Larger differences were reported in the prescribed dosages of these drugs and their use in patients with renal dysfunction. CONCLUSIONS: Cardiologists report practices more in conformity with published guidelines for CHF than do internists and FP/GPs. Because of the large numbers of patients with CHF and their substantial mortality, morbidity and cost of care, these differences may have a major impact on outcomes and health care costs.  相似文献   
32.
氯来源、种类和燃烧物中氯浓度对燃烧过程中二垩英生成有重要影响.在实验燃烧炉中研究1 073K温度下上述三种因素对燃烧过程二垩英生成的影响.二垩英生成浓度在相同氯源和种类条件下与燃烧物中氯含量几乎成正比,且受氯源明显影响.如有机氯化合物或无机氯化物.即使对无机氯化物,在有活性氯存在时也会生成高浓度二垩英,如由盐和面粉形成的水化物中的活性氯.  相似文献   
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Tabletop dry ice coolers (three types; dome model, cap model and tripod model), which are used in kitchens and hotel banquet halls to refrigerate fresh seafood, were investigated to determine whether growth of Vibrio parahaemolyticus was inhibited by their use. On TSA plates containing 1.8% NaCl and fresh seafood (fillets of squid, pink shrimp and yellowtail), V. parahaemolyticus (O3:K6, TDH+) inoculated at 4 to 5 log CFU/sample and left at ambient temperature (25 degrees C) grew by 1.0 to 2.8 orders in 4 hours. In contrast, with tabletop coolers no significant increase in viable count occurred in 3 to 4 hours, confirming that tabletop coolers inhibited the growth of V. parahaemolyticus. The temperature in each tabletop cooler was kept below 10 degrees C for 80 to 135 min, though the CO2 gas concentration in them remained high for only a short time (0 to 75 min). It was presumed that the refrigeration function mainly contributed to growth inhibition. Our results indicate that tabletop dry ice coolers are helpful for prevention of food-borne disease due to V. parahaemolyticus in food-service locations, such as kitchens and banquet halls.  相似文献   
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This study was designed to clarify the mechanism of the decrease of tetrodotoxin (TTX) toxicity during storage in a modified seawater medium (MSWM). When TTX was added to sterilized MSWM, the toxicity of TTX in the medium markedly decreased within 1 day, as determined by a mouse bioassay. HPLC (high-performance liquid chromatography) analysis showed that the peak of TTX was reduced and new unidentified peaks were observed. Omission of the P-1 metal solution from MSWM suppressed the decrease in TTX toxicity and the disappearance of TTX. Further studies indicated that boric acid in the P-1 metal solution triggers this toxicity decrease, indicating that TTX is chemically, not microbiologically, converted to unknown compounds in MSWM.  相似文献   
36.
Development of rapid and simple typing methods is required for analyzing the distribution and contamination routes of food-borne pathogens. We established a simple typing method for Listeria monocytogenes using MLSSCP (Multilocus Single Strand Conformation Polymorphism) analysis. Four virulence genes, hlyA, iap, actA and inlB were amplified by PCR, digested with endonucleases and applied to gels for SSCP. As banding patterns have been shown to reflect even a single nucleotide difference, this method has a potential discriminatory power comparable to that of sequencing analysis. The 64 strains isolated from five meat processing plants were divided into 18 groups by this MLSSCP. Additionally, clustering obtained with this method showed strong correspondence with phylogenetic lineages I and II, and was achieved with much less expenditure in time and cost than is required for other methods, such as MLST. The validity of the MLSSCP lineage classification was confirmed by PFGE, AFLP and ribotyping results. This newly developed MLSSCP method is suitable when obtaining accurate results quickly and simply is crucial.  相似文献   
37.
Listeria monocytogenes serotype 4b strains have been identified as the causative agent in many human listeriosis epidemics as well as in a considerable number of sporadic cases. Due to the genetic homogeneity of serotype 4b isolates, development of rapid subtyping methods with high discriminatory power for serotype 4b isolates is required to allow for improved outbreak detection and source tracking. In this study, multilocus variable-number tandem repeat analysis (MLVA) was developed and used to characterize 60 serotype 4b isolates from various sources. All isolates were also characterized by automated EcoRI ribotyping, single enzyme pulsed-field gel electrophoresis (PFGE) with ApaI, and a multilocus sequence typing (MLST) scheme targeting six virulence and virulence-associated genes. Discriminatory power of MLVA (as determined by Simpson Index of Discrimination) was higher than the discriminatory power of any of the other three methods. MLVA markers targeted were found to be stable and did not change when three isolates were passaged daily for 70 days. Cluster analyses of MLVA, PFGE and MLST consistently grouped the same isolates into three major clusters, each of which includes one of the three major L. monocytogenes epidemic clones (i.e., ECI, ECIa and ECII). We conclude that the MLVA method described here (i) provides for more discriminatory subtyping of L. monocytogenes serotype 4b strains than the other three methods, (ii) identifies three major groups within the serotype 4b, which are consistent with the groups identified by other subtyping methods, and (iii) is easy to interpret. Use of MLVA may thus be recommended for subtyping of serotype 4b isolates, including as a secondary more discriminatory subtyping method that could be used after initial isolate characterization by PFGE or ribotyping.  相似文献   
38.
One of the most important problems in the steelmaking process is an increase of the disposal slag mainly discharged from the dephosphorization process. In order to reduce the quantity of the disposal slag, the complete removal of silicon from molten pig iron is considered very effective before the dephosphorization in the pretreatment process. From this point of view, the desiliconization and the decarburization behavior of Fe-C-Si alloy with CO2 and O2 has been investigated in the present work. It is thermodynamically calculated that silicon should be oxidized in preference to carbon over 0.60 mass pct Si under the condition of sSiO2=a C=1 at 1573 K and is experimentally confirmed that silicon is only oxidized under the condition in actual. Even under the competitive region of desiliconizing and decarbonizing, under 0.60 mass pct Si, silicon is found to be oxidized down to about 0.1 mass pct Si in preference. The overall rate constants for the desiliconization and the decarburization are derived, and the value for the desiliconization is one order of magnitude larger than that for the decarburization. The influence of sulfur is also examined, and the retarding effect is not observed on the oxidation reactions.  相似文献   
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Solutions of the anti-inflammatory drug diclofenac in ethanol and ethanol–water were prepared and mixed with hydrotalcite and hydrotalcite heated at 500 °C. Hydrotalcite pretreated at 500 °C showed a higher adsorption of diclofenac. Diclofenac-hydrotalcites were used for in vitro release experiments to evaluate the percutaneous absorption of diclofenac, using sets of eight Franz cells with membranes of stratum corneum epidermis obtained from human skin; a 2% diclofenac hydroalcoholic gel was used for comparison. Hydrotalcite pretreated at 500 °C is less suitable for release procedures, despite its higher adsorption capacity, whereas diclofenac adsorbed from ethanolic solution by untreated hydrotalcite presents the most efficient sample and shows the best permeation profiles. This sample was selected for the in vivo experiments. Ten healthy volunteers participated on the in vivo experiments: the diclofenac-hydrotalcite appeared to be useful for an efficient application on human skin as inhibitor of the UV-induced erythemas, also better than the usual gel samples.  相似文献   
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