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1.
目的:对血液中的毒鼠强进行提取和检测.方法:采用酸水解及GC/FPD、GC/MS分析的方法,研究酸水解过程中的水解温度、水解强度等方面的影响,并对毒鼠强的GC/MS图谱进行解析,建立了一个定性准确、提取效率高、干扰少的毒鼠强提取分析方法.结果:毒鼠强工作曲线在0.01~0.2μm/μl之间呈线性关系,相关系数r=0.9999.与传统的液-液提取方法相比,血液样品毒鼠强的检出率提高1.69倍.结论:本方法可应用于生物样品中毒鼠强的提取和检测. 相似文献
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Background
Different reinforcements currently available for interim fixed partial denture (FPD) materials do not provide the ideal strength for long-term use. Therefore, the aim of this investigation was to develop a more ideal provisional material for long-term use with better mechanical properties. This study evaluated the effectiveness of polyester fiber reinforcement on different interim FPD materials.Methods
Thirty resin-bonded FPDs were constructed from three provisional interim FPD materials. Specimens were tested with a universal testing machine (UTM). The modulus of elasticity and flexural strength were recorded in MPa. The compressive strength and degree of deflection were calculated from the obtained values, and a two-way analysis of variance (ANOVA) was used to determine the significance.Results
The polyester fiber reinforcement increased the mechanical properties. The modulus of elasticity for heat-polymerized polymethyl methacrylate (PMMA) was 624 MPa, compared to 700.2 MPa for the reinforced heat-cured sample. The flexural strengths of the bis-acrylic and cold-polymerized reinforced samples increased significantly to 2807 MPa and 979.86 MPa, respectively, compared to the nonreinforced samples. The mean compressive strength of the reinforced cold-polymerized PMMA samples was 439.17 MPa; and for the reinforced heat-polymerized PMMA samples, it was 1117.41 MPa. The degree of deflection was significantly greater (P < 0.05) in the reinforced bis-acrylic sample (5.03 MPa), compared with the nonreinforced bis-acrylic sample (2.95 MPa).Conclusion
Within the limitations of this study, polyester fiber reinforcements improved the mechanical properties of heat-polymerized PMMA, cold-polymerized PMMA, and bis-acrylic provisional FPD materials. 相似文献3.
Jianhong Wang Wenwen Zhai Jiaqi Yu Jie Wang Jundong Dai 《Journal of pharmaceutical sciences》2018,107(9):2451-2456
Salvianolic acids and tanshinones both exhibit efficacy in treating idiopathic pulmonary fibrosis (IPF), but their formulation limits their clinical use. This study aimed to prepare the salvianolic acids and tanshinones dry powder for inhalation (SPI) to achieve pulmonary delivery for the treatment of IPF. The variable quantities of salvianolic acids and tanshinones composite powder were optimized using the central composite design-response surface method. Different carriers with various drug-carrier ratios were optimized to prepare SPI. The final optimized formulation of SPI was as follows: InhaLac 230® was selected as the carrier with drug:carrier = 1:6, and the milled lactose InhaLac 400® was added at 5%. The developed SPI characterized with an angle of repose 52.46 ± 1.04°, Carr's index of 34.00 ± 0.50% and showed high lung deposition in vitro, indicating the potential of pulmonary delivery for the treatment of IPF. 相似文献
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Kohorst P Herzog TJ Borchers L Stiesch-Scholz M 《European journal of oral sciences》2007,115(2):161-166
The aim of this in vitro study was to compare the load-bearing capacity of posterior four-unit fixed partial dentures (FPDs) produced with two different yttria-stabilized polycrystalline tetragonal zirconia (Y-TZP) ceramics, one being a presintered material, the other a fully sintered, hot isostatically pressed material. Additionally, as a novel approach, the influence of preliminary mechanical damage upon the fracture force of an FPD has been investigated. A total of 20 frameworks each were milled from presintered zirconia and from fully sintered zirconia. Prior to veneering, 10 frameworks of each material were 'damaged' by a defined saw cut similar to an accidental flaw generated during shape cutting. Before fracture testing, all FPDs were subjected to thermal and mechanical cycling. Additionally, scanning electron microscopy was used to investigate fracture surfaces. Statistical analysis showed that FPDs milled from fully sintered zirconia had a significantly higher fracture resistance compared with specimens made from presintered material, whereas preliminary damage did not have a significant effect. After aging, FPDs made from both materials were capable of withstanding occlusal forces reported in the literature. Therefore, both types of Y-TZP may be suitable for posterior four-unit all-ceramic FPDs, although further prolonged aging experiments and prospective clinical trials are required to prove their fitness for clinical use. 相似文献
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Paola Russo Mariateresa StiglianiLucia Prota Giulia AuriemmaCarlo Crescenzi Amalia PortaRita P. Aquino 《International journal of pharmaceutics》2013
The aim of this study was to evaluate the permeation properties of gentamicin (G) in a novel dry powder form for inhalation through an artificial mucus model. Moreover, since respiratory infections sustained by Pseudomonas are a major cause of sickness and death in CF patients, the susceptibility of P. aeruginosa to engineered G powders was investigated. 相似文献
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Clinical fit of all-ceramic three-unit fixed partial dentures, generated with three different CAD/CAM systems 总被引:3,自引:0,他引:3
In this study, the hypothesis was tested that the marginal and internal fit of CAD/CAM fabricated all-ceramic three-unit fixed partial dentures (FPDs) can be as good as in metal-ceramic FPDs. Twenty-four all-ceramic FPDs were fabricated and randomly subdivided into three equally sized groups. Eight frameworks were fabricated using the Digident CAD/CAM system (DIGI), another eight frameworks using the Cerec Inlab system (INLA). Vita Inceram Zirkonia blanks were used for both groups. In a third group frameworks were milled from yttrium-stabilized Zirconium blanks using the Lava system (LAVA). All frameworks were layered with ceramic veneering material. In addition, six three-unit metal-ceramic FPDs served as control group. All FPDs were evaluated using a replica technique with a light body silicone stabilized with a heavy body material. The replica samples were examined under microscope. The medians of marginal gaps were 75 microm for DIGI, 65 microm for LAVA and INLA and 54 microm for the conventional FPDs. Only the DIGI data differed significantly from those of the conventional FPDs. Within the limits of this study, the results suggest that the accuracy of CAD/CAM generated three-unit FPDs is satisfactory for clinical use. 相似文献
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Passent Ellakany BDS MSc PhD Nourhan M. Aly BDS MSc Fahad Al-Harbi BDS DScD 《Journal of prosthodontics》2023,32(5):423-430
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Miyuki Obata Satoshi Makino Kanako Takahashi Norikazu Watanabe Takayuki Yoshida 《Platelets》2015,26(4):364-369
AbstractWe describe a successful pregnancy and delivery in a patient with platelet disorder. Prophylactic platelet transfusions ensured that there were no bleeding complications during and after cesarean section. Following delivery, we performed whole exome sequencing, using next generation sequencing, to analyze the DNA samples of the patient and her family, and to identify the disease-causing mutation or variant. To identify de-novo mutations systematically, we also analyzed DNA isolated from the parents of the patient and the neonate. We successfully identified a causative novel mutation c.419?G?>?A (p.S140N) in RUNX1 in the patient and the neonate. Mutations of RUNX1 have been reported to be associated with familial platelet disorder and with a predisposition for myelodysplasia and/or acute myeloid leukemia. The patient and the neonate require careful long-term hematological follow-up. Identification of mutations by a through whole-exome analysis using next-generation sequencing may be useful in the determination of a long-term follow-up schedule for the patient. 相似文献