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Objective:To analyze the influence of forming direction on the surface characteristics,elastic modulus,bending strength and fracture toughness of printed parts and the relationship between forming direction and force direction,and to provide scientific basis and guidance for the clinical applica-tion of oral denture base resin materials.Methods:The 3D printing technology was used to print denture base resin samples.The shape and size of the samples referred to the current standard for testing conven-tional denture base materials.The samples used for physical performance testing were cylindrical(with a diameter of 15 mm and a thickness of 1 mm)and printed at different angles along the Z axis(0°,45°,90°).Scanning electron microscope was used to observe the microscopic topography of the different sam-ples.The color stability of different samples was observed by color stabilizer.The surface roughness of the samples was analyzed by using surface roughness tester.The Vickers hardness was measured to ana-lyze the hardness of the samples.The samples used for mechanical performance testing were rectangular(elastic modulus and bending strength:A length of 64 mm,a width of 10 mm,and a height of 3.3 mm;fracture toughness:A length of 39 mm,a width of 8 mm,and a height of 4 mm),divided into two groups:W group and H group.The W group was printed from the bottom up along the Z axis with the length × width as the bottom surface parallel to the X,Y axis plane,while the H group printed from the bottom up along the Z axis with the length × height as the bottom surface parallel to the X,Y axis plane.The forming angles of both groups were equally divided into 0°,45°,and 90°.The elastic modulus,bending strength and fracture toughness of different samples were studied through universal mechanical testing machine.SPSS 22.0 software was used for statistical analysis.Results:The microscopic topogra-phy and roughness of different samples were closely related to the printing direction,with significant differences between the 0°,45°,and 90° specimens.The 0° specimens had the smoothest surface(roughness＜1 μm).The surface of the 45 ° specimen was the roughest(roughness＞3 μm).The microhardness of the 0° sample was the best[(196.13±0.20)MPa],with a significant difference com-pared with the 90° sample[(186.62±4.81)MPa,P＜0.05].The mechanical properties of different samples were also closely related to the printing direction.The elastic modulus,bending strength,and fracture toughness of the 45° samples in the W group were the highest compared with the other groups.The results of elastic modulus showed that in the H group,the 45° specimens had the highest elastic mo-dulus,which was significantly different from the 0° and 90° specimens(P＜0.05).The elastic modulus of 0° and 45° specimens in the W group were higher than those in 90° specimens(P＜0.05).The bending strength results showed that there was no significant difference between the specimens from dif-ferent angles in the H group.The bending strength of the 90° specimens in the W group was the smallest,and there was a significant difference between 90° and the 0° and 45° specimens(P＜0.05);And the bendind strength of the 0° and 45° specimens in the W group was significantly higher than that of the 0° and 45° specimens in the H group(P＜0.05).The fracture toughness results showed that the fracture toughness of the H group specimens was lower than 1.9 MPa m1/2,which was specified in the denture base standard.The 45° samples in the W group were the highest,with significant differences compared with the 0° and 90° samples(P＜0.05).And the 90° samples of the W group specimens were lower than 1.9 MPa m1/2.And the fracture toughness of the 45° specimen in the W group was significantly higher than that of all the specimens in the H group(P＜0.05).Conclusion:The 0° samples had rela-tively better physical properties.The 45° samples had the best mechanical properties.But the fracture toughness of specimens(H group and 90° samples of W group)did not yet meet clinical requirements.That indicated that the characteristics of the 3D printing denture base resin were affected by the printing direction.Only when the performance of the printed samples in all directions met the minimum require-ments of the standard,they could be used in clinical practice.
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Objective To investigate the psychological status of clinical nurses in a class A hospital facing the novel coronavirus pneumonia (NCP), in order to provide effective psychological and social intervention. Methods A total of 867 clinical nurses were randomly selected from the Mianyang Central Hospital. The general information questionnaire, standard self-assessment anxiety scale (SAS) and crisis intervention classification assessment scale (TAF) were used to conduct self-assessment questionnaire survey. Then the data were analyzed by the SPSS22.0 software. Results 38.8% of the nurses had a low risk of infection, 18.0% of them had a medium risk, 29.6% had a medium high risk, and 13.6% had a high risk. The SAS scores of clinical nurses in this hospital were statistically significant different, compared with the Chinese norm value ( P <0.05). The difference between TAF score and the degree of crisis response of nursing students in SARS period was statistically significant ( P <0.05). The majority of clinical nurses had less crisis response to NCP, with 80.7% of them suffered mild cognitive, emotional and behavioral damage, and only 2.0% suffered severe damage. Analysis of related factors showed that department, self-test risk of infection, length of service had significant influence on SAS and TAF scores of clinical nurses ( P <0.05). Conclusion During the period of NCP prevalence, no obvious anxiety and crisis reaction among clinical nurses is found in the third grade hospital. However, the psychological changes of clinical nurses with middle-age, from key epidemic prevention departments and in high risk of self-test infection are more likely to produce anxiety and crisis reaction. Therefore, appropriate and timely psychological intervention should be given.
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Objective To identify the pathogen distribution and antibiotics resistance of blood stream infection(BSI) in the pediatric surgery intensive care unit(PSICU).Methods The clinical data of 138 pediatric patients diagnosed with BSI from January 2011 to December 2015 were collected in PSICU,and the distribution of pathogens and drug resistance were retrospectively analyzed.Results The incidence of BSI was 3.88‰(138/35.524)in the five years,the majority of the BSI cases occurred under one year old,and the mortality was 13.77%(19/138).A total of 179 strains were isolated from blood samples of 138 patients,of which gram-positive bacteria,gram-negative bacteria and fungi accounted for 60.89%(109/179),22.91%(41/179)and 16.20%(29/179)respectively.The most common gram-positive bacteria was coagulase-negative staphylococcus (84/179,46.93%).The predominant gram-negative bacteria were Acinetobacter baumannii(15/179,8.38%),Klebsiella pneumonia(12/179,6.70%) and Escherichia coli(6/179,3.35%).The rate of carbapenems-resistant Acinetobacter baumannii increased continuously in the study period.Non-albicans Candida was the most common fungi (14/179,7.82%).The resistance rate of multi-drug resistant strains to carbapenems significantly increased.Conclusion The incidence of BSI in PSICU increases,and the mortality in children younger than one year is high.Better understanding of distribution of BSI pathogen could provide more effective antibiotic prescription.
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Sepsis is still a leading cause of death in infants and children.It is the result of multiple organ dysfunction syndrome caused by infection.For sepsis,early diagnosis is very important.Biomarkers (procalcitonin,C-reactive protein,pro-inflammatory cytokines,white blood cell count,neutrophil count,left shift and CD64) during the response to infection can be used for early diagnosis.In addition,continuously monitoring these biomarkers can be used for evaluating severity of illness,monitoring of treatment responses and predicting outcome.
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The effective guarantee of the supply of low-price medicine in common use is of great significance for the protection of public health, the safeguard of social equality and the smooth progress of new healthcare reform. On the basis of the governance tools theory, the paper focuses on an analysis of approaches to combine and optimize the diverse utilization of governance tools in order to integrate the means of supply of the low-price medicine in com-mon use. In other words, the paper utilizes the ‘Voluntary-Directive-Mixed’ governance tools framework to provide possible solutions for the supply of low-price medicine in common use, namely, the locations of the voluntary tools ( household and community, volunteers, and market) , the directive tools ( government command-control regulation, establishment of public enterprises, and direct provision) , and the mixed tools ( information disclosure and advice, subsidies, auctions of property rights, tax and user charge) . Lastly the paper proposes specific policy suggestions in four aspects to confirm the total strategy of guaranteeing the supply of low-price medicine in common use:clever use of price leverage, improvements to procurement methods, establishment of an information disclosure system for medi-cine price, and a confirmation of government subsidies and industrial policy strategies.
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Objective To measure the blood levels of mercury and arsenic of mother and umbilical cord, and analyze the relationship between these levels and outcome of pregnancy and complications. To explore the influential factors in order to guide a good birth and good care in pregnancy and lying-in women.Methods A total of 400 cases who were hospitalized in Xinhua hospital from March 2009 to August 2009 were included in this study. The blood levels of arsenic of mother and umbilical cord were determined by microwave digestion method and inductively coupled plasma emission mass spectroscopy method ( ICP-MS),while mercury determination was made using flame atomic absorption spectrophotometer (AAS). In addition, pregnant women were required to fill the questionnaire including their living environments, life styles,diet habits and etc. Results The newborn cord blood levels of mercury and arsenic were positively related to those of their mothers( r =0.88,0.91 respectively, P ＜0.05). The adverse pregnancy rates and complications rates in blood elevated mercury and arsenic groups were significantly higher than in the normal groups( x2 =7.07, 9. 94 respectively, P ＜ 0.01 ). Multiple regression analysis showed that the newborn blood mercury levels were significantly correlated to sea-fish eating, fruits supplement and ventilation during pregnancy. The former was a risk factor( Wald χ2 =8.28, P ＜0.01 ) and the later two were protective factors( Wald χ2 = 9.02, 6.05 respectively, P ＜ 0.05 ). Multiple regression analysis also showed that the newborn blood arsenic levels were significantly correlated to eating canned food, using cosmetics and education degree. Eating canned food and using cosmetics were risk factors(Wald χ2 =7.35, 10.38 respectively,P ＜ 0.05 ) while high education degree was protective factor( Wald χ2 = 8.87, P ＜ 0.05 ). Conclusion The newborn cord blood levels of mercury and arsenic were related to those of their mothers, environmental factors and health care during pregnancy. Health education and care during pregnancy were effective approaches for preventing mercury and arsenic poisoning.