1.Heatstroke prediction machine for single soldier
Chinese Medical Equipment Journal 1993;0(05):-
The heatstroke prediction machine for single soldier is used to monitor body temperature.It can connect with three temperature sensors and transform the temperature of three spots on body surface into electric potential which is linear compensated,magnified and then samplinged by the singlechip.The liquid crystal display shows the temperature of three spots on body surface and the corresponding temperature of anus in turn.With the function of bady temperature alarm and alarm initialization,it becomes a new equipment to monitor body state of the single solider in tropic war zone.
2.Mechanical test and two variable regression analysis of cavity design
Journal of Practical Stomatology 2000;0(06):-
Objective: To study the relationship between the depth and width of cavity design and to analyze the tendency of breaking load in preparations. Methods:Plaster models of mandibular first molar were prepared and magnified by 150%. Cavity on occlusal surface was designed and prepared in a cylinder shape with the depth(mm) of 3.0,4.5 and 6.0,and diameter(mm) of 3.0,4.5 and 6.0,respectively. 8 cavity samples were prepared for each design. The breaking load of the tooth models before and after restoration with self-curing resin was measured by Instron tester.Mechanical model static load test and two variable regression analysis were applied to study the mechanical property of the cavity design. Results:Before restoration, with the increase of depth and diameter, the incidence rate of tooth fracture increased. The width was the main factor. After restoration, the load was undertaken by restoration directly, and could be transfered to tooth and periodontal tissue through restoration uniformly. When the diameter of the cavity increased, the diameter of restoration also increased, and thus decreased the load on local structure of the tooth. With two-regression analysis, the regression equation and regression curve were obtained. Conclusion: The fracture of tooth before and after restoration is related to the diameter and depth of cavity design in cylinder shape. The regression equations of changing tendency of breaking load (Y) in preparation caused by the change of depth(X 1) and diameter(X 2) of cavity obtained by two-regression analysis are presented as follows: Before restoration: Y=1593.317-51.178 X 1-79.489X 2.After restoration:Y=1802.928 -192.461X 1+225.128X 2.
3.Microtensile bonding strength between root canal wall and root canal rehabilitation materials
Journal of Practical Stomatology 1995;0(04):-
Objective:To test the microtensile bonding strength between root canal wall and Bis-Core, and that between root canal wall and Chemil Superior glass-ionomer.Methods:10 human maxillary incisors extracted within one week were kept for another one week after root canal treatment and removeal of the crowns,each root was splited into two parts along with the long axis by Isomet saw, the bonding interface on one third of upside of root dentin smear layer was made with Diamond bur at a high-speed. Then Bis-Core and Chemil Superior glass-ionomer were put on root canal inner surface of each half part of the root respectively, samples with the size of 1.00 mm?1.00 mm were prepared by Isomet saw. Two samples in which bonding interface was perpendiculur to load were selected and fixed in Microtensile testing machine for bonding strength test. Results:Microtensile bonding strength(MPa) between Bis-Core and root canal inner wall and that between root canal inner wall and Chemil Superior glass-ionomer was 20.65?1.72 and 12.89?1.63 respectively(P
4.Micromorphology analysis of bonding interface between material and dentin after root canal rehabilitation
Journal of Practical Stomatology 1995;0(04):-
Objective:To observe the microstructure of interface between material and dentin after root canal rehabilitation. Methods:Three human maxillary incisors extracted within one week were used. After crowns being removed and received root canal treatment, they were used for the study. The root was split into two parts along the long axis, then the bonding interface was made with high speed diamond bur. Bis-Core and Chemil Superior glass-ionomer were stacked on root canal inner wall respectively and the teeth were split along with the long axis with Isomet saw, in order to expose bonding interface. The microstructure of bonding interface of the samples were analyzed by optical microscope and atomic force microscope(AFM). Results: AFM observation of the adhesive interface specimens showed that Chemil Superior glass-ionomer and teeth knitted together completely and no filling invaded into dentin tube. While the bonding interface between Bis-Core and dentin, dentin primer infiltrated into dentin tube and matrix around through the smear layer and colophony protruded. Conclusion:The observations reveal the extent of resin penetration into the dentinal tubules provides a very strong bonding. This is a fundamental cause of resin better bond to tooth.
5.A phantom study on the effect of target diameter and target-to-background ratio on the measurement of SUVmax in PET
Yan CUI ; Song CHEN ; Yaming LI
Chinese Journal of Nuclear Medicine and Molecular Imaging 2013;33(4):294-297
Objective To investigate the effect of target diameter and target-to-background ratio (TBR) on the measurement of SUVmax [| (true SUV-SUVmax)/true SUV | × 100%,△SUVmax) in PET.Methods Six cylinders with various diameters from 5 to 29 mm were inserted in National Electrical Manufacturers Association (NEMA) NU 2-1994 phantom.The six cylinders and background of phantom were filled with18F-FDG solution.Six different TBRs (1.79,3.70,6.25,10.59,14.87 and 17.88) were obtained by changing the 18F-FDG concentration in the six cylinders.The PET data were acquired in the 2D mode,and the target's inner diameter and SUVmax were measured.The logarithmic fitting curves of △SUVmax with diameter in different TBRs using equations (y=aln(x)+b) were acquired by Microsoft excel,| a| as the influence power of diameter on △SUVmax.Statistical analysis was performed with Pearson correlation test and curve estimation utilizing SPSS 17.0.Results The Pearson correlation coefficient between △SUVmax and diameter was-0.806 (P<0.01).△SUVmax was inversely correlated with the diameter.When the diameter (the inner diameter measured on PET images) was 4.0 mm,△SUVmax could be as high as 79.73% with different TBRs.The Pearson correlation coefficient between the influence power of diameter on △SUVmax (| a |) and TBRs was 0.848 (P<0.05).When TBR was 6.25,10.59 and 14.87,the corresponding |a| was similar:38.019,39.998 and 39.362,respectively.When TBR was 17.88,| a| was the highest as 43.234.When TBR was 1.79 and 3.70,|a| was much smaller:14.141 and 23.411 respectively.Conclusions The lesion diameter is inversely correlated with △SUVmax.The influence power of diameter on △SUVmax is strongly correlated with TBR.Therefore,the effect of target diameter and TBR on the measurement of SUVmax should be taken into consideration for follow-up studies.
6.In vitro study on fracture resistance of teeth restored with direct and indirect composite resin
Yaming CHEN ; Hailan FENG ; Yazhou SUN
Journal of Practical Stomatology 2000;0(05):-
0.05).Significant difference was found between group ④ and ①,②,③ or ⑤(P
7.Tooth fracture resistance study after composite resin inlay by three dimensional finite element analysis
Lei MEI ; Yaming CHEN ; Lingyi LV
Journal of Practical Stomatology 1996;0(02):-
Objective: To evaluate fracture resistance of teeth restored with inlay restorations of direct and indirect composite resin. Methods:Three dimensional finite element analysis (3D FEA) was used in present research. Two types of load were applied to investigate the change of tooth fracture resistance after restored with MOD inlay. Group 1,2,3,and 4 were restored with four kinds of materials:group 1,indirect composite resin inlay( Tescera, Bisco USA);group 2, direct composite inlay(Renew Bisco USA);group 3,ceramic; and group 4, Co-Cr alloy. Defect tooth or intact one was served as the control group. Results:Tooth fracture resistance in group 1,2,3 and 4 were improved, Fracture resistance in group 1 and 2 were similar to intact tooth group, while the fracture resistance in group 3 and 4 was different effect when compared to intact tooth. Conclusion: Both direct and indirect composite resin inlay could strengthen fracture resistance of restored teeth. No obvious difference between direct and indirect composite resin on tooth resistance was found.
8.Study on bonding interface and microstructure of different resin composite inlays
Yaming CHEN ; Hailan FENG ; Lei MEI
Journal of Practical Stomatology 1996;0(02):-
Objective:To evaluate the characteristics of bonding interface and microstructure of different resin composite inlays. Methods:Different composite resins and adhesives were used for restoration of extracted molars, the results were evaluated under scanning electron microscope(SEM) and atomic force microscope(AFM).Results:The microstructure feature of Tescera was with higher density when compared with that of other conventional resins,and fewer small holes could be seen in Tescera. AFM pictures showed that Tescera was with a very smooth surface. Indirect composite resin could be combined with resin bonding agent tightly and infiltrated each other. The interface between direct resin inlay material and resin bonding agent was very clear,and no obvious interfiltration could be seen under SEM and AFM. Conclusion:After treatment with water, heat,light and pressure, the physical properties of indirect composite resin is improved effectively, and obvious infiltration can be found in the interface.
9.Research progress on the indwelling nasal jejunum enteral nutrition care of critical patients in neurosurgery department
Xing CHEN ; Yaming GE ; Jie WANG
Chinese Journal of Practical Nursing 2017;33(z1):92-94
The research reviews the purpose, significance and indwelling method of indwelling nasal jejunum in critically ill patients with neurosurgery in recent years and It also studies the effects of indwelling on organ function. For example, improving pulmonary ventilation function can reduce the mechanical ventilation time of patients with mechanical ventilation; can effectively promote intestinal tissue and function, reducing electrolyte disturbance;and long-term catheter can affect the liver function, the occurrence of gastric retention, diarrhea, obstruction of the pipeline and the related complications. The authors hope to provide a reference for the clinical care. At present, the use of nasal jejunum is the trend of enteral nutrition in critically ill patients with neurosurgery, but the replacement time of nasal jejunum tube, oral care and other related complications are lack of corresponding research.
10.The design of software system of pulse oximeter
Xiaodan TAN ; Yaming CHEN ; Qinkai DENG
Chinese Journal of Medical Physics 2000;17(4):211-212
A software system of the pulse oximeter is presented in this paper. Based on Franklin C, this software system includes three main parts, one part is to automatically regulates the base line of signal, the second part is a controlled integral module,and the third part is a digital signal processing module. As the result, the pulse oximeter is satisfactory to clinical monitoring.