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11.
探索了磷酸四钙(Ca4(PO4)2O,TTCP)的制备,并合成了磷酸钙骨水泥(CPC),对CPC固化时间、引起浸泡液pH值的变化、抗压强度、产物物相组成及微观结构进行了研究。结果表明:在真空条件下、1500℃下煅烧6h可制得TTCP,并含有少量CaO。CPC初凝时间为4min、终凝时间为15min,浸泡1d和7d后的抗压强度分别为20MPa和35MPa,浸泡液的pH值在6.4~8.9之间变化,这些性能均符合临床用CPC的性能要求。CPC水化产物为片状或针状羟基磷灰石(Ca5(PO4)3OH,HA),相互交错呈连续分布的网状结构,这种结构有利于材料强度的提高。实验研制的CPC材料可用于骨缺损的修复治疗。  相似文献   
12.
Purpose: This laboratory study aimed at investigating the effect of setting expansion (SE), which could enlarge a wax pattern by concurrent exothermic reaction.
Materials and Methods: Two phosphate-bonded investment materials (Rematitan Plus, T-invest C & B) and alumina-magnesia-based investment material (Titavest CB) were subjected to setting temperature and SE measurements (n = 10). Full-crown wax patterns were prepared from metal dies having the same design. Crown castings (n = 6) were made using a one-chamber high-pressure casting machine. Commercially pure titanium ingot (Japanese Industrial Standard Class II) was used for each casting. Dimensional accuracy of the cast crowns was expressed by marginal discrepancy for a pair of wax pattern and casting prepared from the same die. All results were then subjected to regression analysis.
Results: Rematitan Plus gave the highest setting temperature (about 70°C) and the highest SE (1.16 ± 0.01%) almost concurrently. The result was that Rematitan Plus produced oversized crowns from the lowest thermal expansion (TE) value (0.53 ± 0.05%) reducing the linear correlation to 0.80 ( p < 0.05). No significant linear relationship was found between SE of investment material and crown-casting accuracy.
Conclusions: The almost concurrent occurrence of high SE and high setting temperature generation in Rematitan Plus enlarged the wax pattern and effectively supplemented its low TE to produce oversized crowns. Despite this adverse effect, the correlation between TE and crown accuracy was still high. It is generally expected that the TE values given by manufacturers predict crown accuracy, when uniform TE, small SE, and minimum heat generation during setting are assured.  相似文献   
13.
目的应用层次分析法综合分析评价张浦镇食品安全承诺备案管理模式绩效。方法将食堂卫生状况诸因素先按支配关系分组,使之成为有序的递阶层次结构,通过两两比较,确定层次诸因素相对重要性,然后综合判断,确定推行承诺备案管理模式后卫生状况是否优于推行前和同期未推行的。结果推行承诺备案管理模式后除场所面积、布局流程两项指标外,其它如专间卫生、三防设施、生熟分开等各项指标合格率均成上升趋势,经层次分析法分析,企业食堂食品卫生状况综合指数V:V已推行(推行后)>V未推行,V推行后>V推行前。结论层次分析法有较大的应用潜力,在进一步推广承诺备案管理模式的同时,仍须全面推行企业食堂食品卫生量化分级管理,促使企业食堂加大硬件设施改造的投入,使场所面积职工用餐人数比、功能区合理布局等硬件设施指标符合国家规定的卫生要求。  相似文献   
14.
本文就G20杭州峰会医疗保障医疗点的设置原则和场馆医疗点、定点酒店医疗点的布置作了阐述;并就医疗保障医疗点的人员配置、设备配备、处置流程、保障任务等作了介绍,为国际大型会议活动医疗保障医疗点的设置提供借鉴。  相似文献   
15.
ObjectivesThe author proposes to explore some of the characteristics of clinical practices and setting “at the limits.” Particular consideration is given to the underlying logics of co-construction and their implications for clinical work and the process of subjectivation.MethodClinical settings “at the limits” are defined as practices that are situated at the limits of psychological care or at the limits of the usually identified setting. They are specifically aimed at subjects with boundary problems and difficulties in subjectivation. Based on several types of setting, the dynamics of co-construction at work between patient(s) and therapist(s) and between setting and institution are studied, leading to the identification of some clinical benchmarks for the specificities of these treatments and the issues they raise from the point of view of the work of subjectivation.ResultsThe identification of the dynamic of co-construction specific to these clinical practices highlights the necessary congruence of these devices with the psychic needs of the subject, which implies a particular attention paid by the clinician to the effects produced in the therapeutic relationship by the setting. Three major characteristics of clinical settings “at the limits” are identified: unconditional welcome; appropriation of the setting; and sharing as a major organizer of the clinical encounter.DiscussionTaking into account the dimension of intersubjectivity and the singular use that the patient will make of the device makes it possible to underline the transitional virtues of the work of co-construction, notably in relation to the transference/counter-transference dynamic.ConclusionNowadays, clinical settings “at the limits” constitute a particularly heuristic and rapidly expanding field of research, contributing to refining and remodelling our clinical practices and theoretical models.  相似文献   
16.
Gypsum products are one of the most widely used materials in dentistry. The wide use of plaster of paris motivated a number of manufacturers to introduce different brands of the profession but their physical and mechanical properties were still questionable. The aim of this study was to access, compare and evaluate the physical properties of different brands of laboratory gypsum available in Indian dental market. Seven brands namely Calspar, Rajhans, Elephant, Horse, Lion, Johnson and Shree Niwas Chemicals were selected for the comparison of their particle size, consistency and setting time. The obtained data were tabulated and compared with Indian, Australian and US standard specification. Statistical analysis for comparative study was done. It was found that none of the brands were up to mark. The present study shall be able to provide some beneficial information regarding their quality control and guide the manufacturers for improving the standardization of their products so that most suitable type of material may be available to the profession.  相似文献   
17.
The School Setting Interview (SSI) is an internationally used client-centred interview assessment that specifically investigates the student–environment fit for students with physical disabilities. In this study the Rasch measurement model was used to examine validity of the SSI; specifically, whether or not the SSI measures a unidimensional construct. Data for analysis included SSI assessments of 87 Swedish students with physical disabilities aged between 8 and 19 years of age. The results of the Rasch analysis revealed that all items had acceptable infit MnSq and z values supporting evidence of construct validity of the SSI. The established order of the difficulty of the items was also shown to be in acceptable congruence with the theoretical basis for item development. In addition, the analysis revealed aspects of the SSI that need improvements, such as the need for more challenging items and refinements of the manual. Further investigations of validity in different cultural contexts are recommended.  相似文献   
18.
Women with pre-eclampsia have an increased risk of cardiovascular disease later in life. The aim of the study was to establish the presence and pattern of arterial stiffness in women previously with pre-eclampsia from a semi-rural region of South Africa. This was a prospective longitudinal study which involved 36 previously pre-eclamptic women and 86 non-pregnant controls (NPC) who had a past history of non-complicated pregnancy. Maternal wave reflection (augmentation index) and carotid-femoral pulse wave velocity were assessed noninvasively, using applanation tonometry with the SphygmoCor device. Endothelial function was assessed by EndoPAT 2000 device; pneumatic probes were fitted to the index fingers; induced flow-mediated reactive hyperemia; the ratio of the readings before and after occlusion was then used to calculate the score, the reactive hyperemia index (RHI) as a measure of endothelial function.

Pulse wave velocity remained significantly higher in previously pre-eclamptic women than non-pregnant controls up to three months after delivery (p < 0.05), then it reduced to nonsignificant values. All blood pressure indices (central and brachial pressures), were higher in previously pre-eclamptic women as compared to nonpregnant controls up to one year postpartum.

Regional (aortic) arterial stiffness, though it persists for some time after delivery, is transitory in previously pre-eclamptic women from the rural Africa setting. However, their increase blood pressure is an indication of compromised arterial compliance in women previously with pre-eclampsia.  相似文献   

19.
目的动脉瘤性蛛网膜下腔出血(aSAH)伴脑内血肿的早期体位摆放。方法完成患者急性期在床上渡过体位摆放的护理,杜绝不良卧位给病人造成的关节挛缩,肌肉萎缩等严重后果。结果正确的体位摆放过渡到移位是为患者早期功能锻炼提供了可靠保障,并为肢体恢复和缩短住院时间打下基础。结论实践证明,体位摆放—移位—肢体恢复,不但挽救了患者的生命,并把残疾损害降到最低程度,积极努力地帮助患者充分发挥残余功能,达到生活自理,最后完全康复。  相似文献   
20.
OBJECTIVES: The main objective is the characterisation of the setting reaction in glass ionomer cements based on experimental ionomer glasses with different fluorine content and a commercial glass ionomer cement liquid by using 13C CP/MAS-NMR, 29Si, 27Al and 31P MAS-NMR spectroscopy in order to receive information specifically about the cross-linking process. METHODS: Different fluorine containing glass compositions based on 4.5SiO2-3Al2O3-1.5P2O5-(5-z)CaO-zCaF(2) where z=0-3, were mixed with a commercially available polymer liquid to form glass ionomer cements. The cements were subjected to 27Al, 13C CP/MAS, 29Si, and 31P MAS-NMR analysis. RESULTS: The 27Al spectra showed clearly the formation of six-fold coordinate Al(VI), that may crosslink the carboxyl groups in the poly-acid molecules. A shift towards to more positive values of the carboxyl peak in the 13C CP/MAS-NMR spectra showed clearly the proton dissociation of the carboxyl groups. A shift towards more negative values was observed in the 29Si MAS-NMR spectra, suggesting formation of hydrated silica gel and consequently formation of additional Si-O-Si bonds. 31P MAS-NMR spectra also reflected changes in the coordination state around a PO4(3-) tetrahedron. Increasing the fluorine content of the glasses resulted generally in increased reactivity during setting, due to promoting cross-linking and repolymerisation of the silicate phase, followed by clear changes in the MAS-NMR spectra. CONCLUSIONS: The cross-linking process during the setting reaction of glass ionomer cements can be followed by MAS-NMR spectroscopy observing the conversion of Al(IV) to Al(VI). The acid base setting reaction is completed in 1 day and no further significant changes in the MAS-NMR spectra can be observed. Further study is required in order to understand the role of phosphorus.  相似文献   
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