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1.
Several aspects of the microbiological quality of natural waters, especially recreational waters, have been reviewed. The importance of the water as a vehicle and/or a reservoir of human pathogenic microorganisms is also discussed. In addition, the concepts, types and techniques of microbial indicator and index microorganisms are established. The most important differences between faecal streptococci and enterococci have been discussed, defining the concept and species included. In addition, we have revised the main alternative indicators used to measure the water quality.  相似文献   

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The microbiological quality has been evaluated in 6 batches of yogurt (plain, flavoured and fruit-added) produced commercially in France and purchased in Spain. The essential microflora: Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, and contaminants (coliform bacteria, yeasts and molds) were checked. The pH was also measured. The totality of the samples tested fulfilled French and Spanish regulation with respect to the presence of viable yogurt organisms. Likewise, in 100% of the yogurts, counts of contaminants were under 10 cfu/g. The pH ranged between 3.92 and 4.19.  相似文献   

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A meeting organized by Nederlands Tijdschrift voor Geneeskunde discussed the various interfaces of the quality of care, cost-effectiveness and health care. Cost-effectiveness analyses can contribute greatly to the quality of health care, but such research is methodologically complicated. Also, the effectiveness of particular interventions or therapies should be taken into account, if possible evidence-based, in the introduction of standards or guidelines for health-care workers. In practice, however, owing to various circumstances, the implementation of such guidelines leaves something to be desired.  相似文献   

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对热处理易出现的丸料压入、钢板下表面炉底辊压痕和钢板边部挤压变形等质量缺陷进行原因分析。通过对抛丸机组改造,在抛丸机上表面增加刮板和吹扫装置,改造下表面抛丸辊道;采用专用的钢板进行洗炉,清理黏附在炉底辊道表面的氧化铁皮;优化装炉制度和工艺参数,制定装炉偏移控制等措施,有效控制热处理钢板的表面质量。钢板热处理质量得到明显改善,提高了产品质量的控制能力。  相似文献   

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The production of toxin by a 10-strain mixture of proteolytic Clostridium botulinum in fresh produce packaged in polyethylene films having high (7,000 cc/m2/24 h; HOTR) and low (3,000 cc/m2/24 h; LOTR) relative oxygen permeability was determined. Shredded cabbage and lettuce inoculated with approximately 10(2) spores/g were placed in bags composed of the two films (1.4 kg/bag), and the bags were then vacuum sealed. Produce was stored at 4, 13, and 21 degrees C for up to 21 (cabbage) or 28 (lettuce) days and analyzed periodically. At each sampling time, the gas composition within the bags, pH of the produce, and microbial populations (total aerobic and anaerobic microorganisms, lactic acid bacteria, psychrotrophic bacteria, and yeasts and molds) were determined. In addition, the presence of botulinal toxin was determined using the standard U.S. Food and Drug Administration mouse bioassay protocol. Bags made of HOTR film prolonged sensory quality of cabbage and lettuce, especially at 13 and 4 degrees C. Packaging material had an effect on the growth of various groups of microorganisms; however, there was not a general trend. For example, lettuce packaged in HOTR bags had higher aerobic microbial populations than that packed in LOTR, but no significant difference (P < or = 0.05) was observed with cabbage. Growth of psychrotrophic bacteria was greater in vegetables packaged in HOTR film while growth of yeasts and molds was not affected by either packaging film. Most differences in microbial populations in produce packaged in LOTR and HOTR films were less than 1 log10 CFU/g. Botulinal toxin was not detected in cabbage or lettuce packaged in either film or stored under any test condition.  相似文献   

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This replication of Ott's study [Ott, B. (1986). An Ethical Problem Facing Nurses: The Support of Patient Autonomy in the Do Not Resuscitate Decision. University Microfilms International, Dissertation, Texas Women's University] and McLaughlin et al.'s study [McLaughlin, T., Brown, O. and Herman, J. (1988). Nurses' Perception of the Support of Patient Autonomy in Do Not Resuscitate Situations. Unpublished Research Report] explored hospital staff nurses' perceptions of their role in supporting patient autonomy in the do-not-resuscitate (DNR) decision. One-hundred and sixty-five registered nurses (RNs) participated: 93 from the Veterans Administration Medical Center and 72 from a private non-profit hospital. Ott's questionnaire had four hypothetical cases in which a DNR decision would probably be made with three questions about whose opinion would most support patient autonomy and whose opinion would actually be regarded as the most appropriate for making the DNR decision. Seventy per cent of perceptions of the person whose decision would be best able to support the patient's autonomy in the DNR decision and 51% of the people perceived to actually be deemed most appropriate to make the DNR decision were consistent with Ott's DNR Decision Model.  相似文献   

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总结了电气电子领域使用的六方氮化硼(hexagonal boron nitride,h BN)导热填料制备方法,介绍了近几年h BN填充树脂基复合材料的研究进展,研究了导热树脂复合材料的导热机理和导热模型,讨论了h BN填料的形貌、粒度、颗粒复配及表面改性方法等因素对材料导热性能的影响,并对h BN填充高导热树脂复合材料的发展方向进行了展望。  相似文献   

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Administered countercontrol behavioral therapy for sleep-maintenance insomnia to 34 insomniacs (aged 35–78 yrs) in small groups. 22 Ss received immediate and 12 received delayed treatment. Three self-report measures of sleep disruption were collected on daily sleep diaries at baseline, termination of treatment, 1-mo follow-up, and 12-mo follow-up. Although amount of time awake at night was correlated with age, response to treatment was not. Even though older Ss experienced more time awake after sleep onset prior to treatment, they were able to profit from therapy as well as the younger insomniacs. Countercontrol therapy reduced the sleep complaint for the total group by about 30% at the end of treatment, with gradual improvement continuing through a 4-wk follow-up. It is suggested, however, that sleep-maintenance insomnia may be more difficult to treat than sleep-onset problems. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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通过对具体热处理炉内钢板运行速度的分析,旨在找出此类型炉子如何实现钢板在炉内稳定、可靠运行的解决方案,以期通过稳定、可靠的运行提高作业率,达到高产、节能、降耗的目的.文章综合运用了经验值、逻辑推理、综合分析、归纳总结等方法,从源头--钢板的在炉时间入手,一步步通过在炉速度、最低速度、运行方式最终推导出节能新工艺的载体--钢板运行速度,并解决了工艺中摆动运行的具体操作.  相似文献   

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BACKGROUND: Reading acuity as well as reading speed are good predictors of everyday visual function. As visual acuity tests are poor predictors of the real-world function, performance-based tests, e.g., reading speed measurements, can be used for the determination of visual function. Thus, a German reading chart was developed in order to evaluate reading acuity as well as reading speed. METHODS: Print size is defined as the height of a lower case x and progresses logarithmically from one phrase to another (factor: 1.25). Reading acuity is determined in LogRAD (Reading Acuity Determination). 32 short German phrases were created, comparable concerning grammatical difficulty as well as in number (n = 14), length and position of words. The reading speed parameters measured with a stop-watch in 160 persons (aged: Phi = 21a +/- 3.8a) were calculated in words per minute (w/min). Out of the 32 phrases the 24 most similar ones were selected statistically and used for the reading charts (Radner Reading Charts). With these reading charts a reading acuity score (LogRAD-score) can be calculated considering reading errors in words of different length. Reading speed can be determined at the same time. Reading acuity (LogRAD-Score) was measured in 32 normal eyes of 16 students and compared to the angular visual acuity (LogMAR). RESULTS: The mean reading speed of the test persons was 211.8 +/- 34.1 w/min. 24 phrases fulfilled the test item criteria for the reading chart: mean +/- 0.25 x SD. The reliability analyses yielded an overall Cronbach's alpha coefficient of 0.98! The mean visual acuity measured in 32 eyes was -0.115 +/- 0.097 LogMAR and the mean reading acuity score was +0.026 +/- 0.091 LogRAD. The mean difference was +0.104 +/- 0.066 and the correlation between LogMAR and LogRAD was good (r = 0.59). CONCLUSIONS: With these reading charts it is for the first time possible to simultaneously determine reading acuity as well as reading speed in German. The high reliability of the 24 phrases and the high correlation between LogMAR and LogRAD leads us to expect a good reproducibility of the reading acuity evaluations. For the "Radner Reading Charts" we have shown that print size is the main reason for changes of reading speed.  相似文献   

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An analysis of the cement mantle obtained with the Exeter impaction allografting system at one centre showed that it was either deficient or absent in almost 47% of Gruen zones. We therefore examined the mantle obtained using this system at another hospital and compared the results with those from the CPT and Harris Precoat Systems at other centres. The surgical indications for the procedure and the patient details were broadly similar in all four hospitals. There was some variation in the frequency of use of cortical strut allografts, cerclage wires and wire mesh to supplement the impaction allograft. Analysis of the cement mantles showed that when uncertain Gruen zones were excluded, the incidence of zones with areas of absence or deficiency of the cement was 47% and 50%, respectively, for the two centres using the Exeter system, 21% for the CPT system and 18% for the Harris Precoat system. We measured the difference in size between the proximal allograft impactors and the definitive prosthesis for each system. The Exeter system impactors are shorter than the definitive prosthesis and taper sharply so that the cavity created is inadequate, especially distally. The CPT proximal impactors are considerably longer than the definitive prosthesis and are designed to give a mantle of approximately 2 mm medially and laterally and 1.5 mm anteriorly and posteriorly. The Harris Precoat proximal impactors allow for a mantle with a circumference of 0.75 mm in the smaller sizes and 1 mm in the larger. Many reports link the longevity of a cemented implant to the adequacy of the cement mantle. For this reason, femoral impaction systems require careful design to achieve a cement mantle which is uninterrupted in its length and adequate in its thickness. Our results suggest that some current systems require modification.  相似文献   

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Translated from Metallurg, Vol. 39, No. 4, p. 25, April, 1995.  相似文献   

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Giant-cell bone tumors display a locally aggressive growth pattern, frequently recur if no adjuvant treatment is given, and may potentially metastasize. By virtue of their biological behavior and typically juxta-articular localization, giant-cell bone tumors require specific surgical management. Thus, an intralesional tumor excision must be supplemented by adjuvant bone cementing, possibly combined with instillation of phenol or cryotherapy. These combined treatment modalities assure a high-quality procedure, defined as the actual way medical care is delivered, by promoting the quality of the outcome, defined as the effect of a medical procedure on the patient's state of health.  相似文献   

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Type 308 weld metal overlaid on a low-alloy steel by a submerged arc welding (SAW) process using wide strip electrodes can become sensitized by not only postweld heat treatments (PWHTs) at around 600 °C but also low-temperature aging (LTA) at 500 °C for 24 hours after PWHT. A slow strain-rate test (SSRT) in oxygenated, high-temperature pure water revealed that type 308 SAW weld metals after PWHT were susceptible to intergranular stress corrosion cracking (IGSCC) when sensitized such that the intergranular corrosion (IGC) rate in the modified ASTM A262E test exceeds 1 μm/h. The effect of microstructure (ferrite phase distribution) on the sensitization behavior was evaluated using a microstructural parameter N L β−γ . Though mostly useful, the average N L β−γ was not always accurate in distinguishing IGC-susceptible, SAW overlay weld metals. However, local N L β−γ , newly introduced to deal with a rather large fluctuation in ferrite distribution within SAW overlay weld metals, was partly able to explain the IGC susceptibility of a theoretically resistant heat with a high average N L β−γ . The beneficial effect of surface remelting by plasma arc on the IGC resistance was described.  相似文献   

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