Objective:To study effects of the cooling rate on the bonding characteristics of titanium porcelain bonded to cast titanium.Methods:According to ISO 9693,24 cast titanium plates(25 mm?3 mm?0.5 mm)were prepared.The middle of the samples(8 mm?3 mm) were bonded with bonding porcelain,opaque porcelain and dentin porcelain.The specimens from each porcelain-metal combination group were randomly assigned into four experimental cooling rate conditions,namely cooling rate of 15,40,50 and 100 ℃/min.A three-point-flexure-test was used to evaluate the bonding strength of titanium porcelain bonded to cast pure titanium.SEM/EDS were taken to characterize the failed surface of the titanium-porcelain interface.Statistical analyses were made by one-way analysis of variance(ANOVA).Results:The bonding strength of 15 ℃/min group was significantly higher than other groups.There were no significant differences in bond strength between 40 ℃/min and 50 ℃/min groups.SEM/EDS revealed that with an increase cooling rate,the remained porcelains on the titanium side were decreased.Conclusion:The 15 ℃/min cooling rate might be an effective method to improve the titanium-porcelain bonding strength.

Objective:To evaluate the effects of three bond agents on bond strength of titanium- ceramic system. Methods: The pure titanium specimens were randomly divided into three groups. Three different manufacturers' porcelains(Super Ti22,Duceratin,Titankeramik) were used specially for titanium- ceramic bonding. The specimens in each group were further divided into two subgroups:bond agent group and no bond agent group. Bond strength of specimens was measured by the three- point bending test according to ISO9693. The titanium- ceramic interfaces were investigated by SEM/EDS. Results:The bond strength of Super Ti22(35.84±2.17) MPa and Duceratin(35.45±2.37) MPa with bond agent group was significantly higher than that of no bond agent group(P<0.05). Titankeramik with bond agent group showed a little higher bond strength than without bond agent, but no significant difference in statistics(P>0.05). The interfaces of Super Ti22 and Duceratin with bond agent groups were compact, while there were visible cracks and pores at the interface of other groups. Conclusion:The application of bond agent can improve bond strength of titanium- ceramic system.

Objective; To evaluate the influence of electrolyte's concentration at micro-arc oxide treatment on the bonding strength of titanium to porcelain. Methods; CP titanium specimens with size of 25 mm ×3 mm ×0. 5 mm were treated with micro-arc oxidation (MAO) in Na_2SiO_3 solution of three different concentrations. After ultra-low-fusing porcelain was applied, a three-point-flexure-test was used to evaluate the bonding strength of titanium to porcelain. The surface of the specimens was observed by SEM and EDS, as well as the interface between titanium and porcelain. Results; The bonding strength values between titanium treated with MAO and porcelain was significantly higher then the control groups, Croup 20 g/L has the highest bonding strength values. SEM/EDS suggested that a porous thin layer of oxide which contains Si element is created by MAO, and higher concentration of Na_2SiO_3 leads to more Si element in oxide. Conclusion; MAO treating can improve the bonding strength between titanium and ceramic. Electrolyte's concentration has an effect on the bond strength between titanium and porcelain.

Objective:To evaluate the effects of three bond agents on bond strength of titanium-ceramic system.Methods:The pure titanium specimens were randomly divided into three groups.Three different manufacturers' porcelains(Super Ti22,Duceratin,Titankeramik)were used specially for titanium-ceramic bonding.The specimens in each group were further divided into two subgroups:bond agent group and no bond agent group.Bond strength of specimens was measured by the three-point bending test according to ISO9693.The titanium-ceramic interfaces were investigated by SEM/EDS.Results:The bond strength of Super Ti22(35.84?2.17)MPa and Duceratin(35.45?2.37)MPa with bond agent group was significantly higher than that of no bond agent group(P0.05).The interfaces of Super Ti22 and Duceratin with bond agent groups were compact,while there were visible cracks and pores at the interface of other groups.Conclusion:The application of bond agent can improve bond strength of titanium-ceramic system.

Objective To observe the clinical efficacy of Jianpi Huatan Decoction plus Zhongwan (RN12) moxibustion on patients of mild to moderate stable chronic obstructive pulmonary disease (COPD) with syndrome of qi deficiency of lung and spleen, and analyze the related influencing factors. Methods With prospective randomized clinical trial, 140 cases of mild to moderate stable COPD were randomized into two groups (70 cases for each group). Treatment group was treated by Jianpi Huatan Decoction plus Zhongwan moxibustion based on western medicine, and control group was only treated by western medicine. Both groups were treated for 12 weeks and followed up for 12 weeks. Scores of clinical symptoms and quality of life questionnaire were examined, and multiple logistic regression analysis was used to find possible impacting factors on the effect. Results Symptoms were significantly alleviated after treatment (P<0.01) in both groups. The clinical effects and quality of life in treatment group were significantly improved than the control group (P<0.01). There were no significant changes in life quality of control group ( P>0.05). Multiple logistic regression analysis showed that different therapies and severity of COPD were the major influencing factors of clinical effect (P<0.05, P<0.01). Conclusion Jianpi Huatan Decoction plus Zhongwan moxibustion had significant therapeutic effect on mild to moderate stable COPD patients with syndrome of qi deficiency of lung and spleen by alleviating symptoms and improving quality of life. Treatment style and severity of COPD are the main influencing factors.

Objective:To investigate the effect of exposure to histological chorioamnionitis(HCA) on premature infants with respiratory distress syndrome(RDS)complicated with bronchopulmonary dysplasia(BPD).Methods:The clinical data of premature infants with gestational age<32 weeks and survival>14 days who were born in the department of obstetrics and admitted into NICU at Qingdao Women and Children′s Hospital from January 2018 to December 2020 were collected.According to placental pathology, they were divided into positive HCA + positive RDS group(observation group)and negative HCA + positive RDS group(control group). T-test, rank sum test and χ2 test were used to analyze the occurrence and clinical characteristics of BPD between the two groups.For premature infants with positive HCA who were diagnosed as BPD, Spearman rank correlation was used to analyze the correlation between HCA stage and BPD severity. Results:There were a total of 162 premature infants with RDS.The average gestational age at birth was 29.29(28.29, 30.43) weeks, and the average birth weight was 1.32(1.13, 1.55)kg; the incidence of BPD was 69.8%(113/162), and the mortality rate of BPD was 2.7%(3/113). There were 114 cases in the observation group and 48 cases in the control group.The incidence of BPD in the observation group was 76.3%(87/114), which was higher than that in the control group(54.2%, 26/48), and the difference was statistically significant( P<0.05). Further study of 87 premature infants with positive HCA who were diagnosed as BPD showed that, the correlation between the stage of HCA and the severity of BPD had not been confirmed( rs=0.062, P=0.571). Serum C-reactive protein before the mother used antibiotics and procalcitonin on the first day after birth in the observation group were higher than those in the control group, and the differences were statistically significant( P<0.05). Among 113 premature infants with RDS who were diagnosed as BPD, the time of antibiotic use, length of stay in intensive care unit and hospitalization cost in positive HCA group were higher than those in negative HCA group, and the differences were statistically significant( P<0.05). Conclusion:HCA exposure will increase the risk of BPD in premature infants with RDS.In addition, HCA also increases the intake period of antibiotics, length of stay and cost of intensive care unit in premature infants with BPD.

AIM: To study effects of urokinase-type plasminogen activator (uPA) signal transduction on expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) in giant cell tumor of bone (GCT). METHODS: Expression of uPAR, MMP-2 and TIMP-3 in GCT tissue was detected by immunohistochemistry. Phosphorylation level of mitogen-activated protein kinase (p44) in uPA/uPAR signal pathway in cultured GCT cells was detected by immunoprecipitation. The expression of MMP-2 and TIMP-3 in cultured cells after treatment with uPA-ATF or anti-uPAR antibody was also detected by Western blotting. RESULTS: 1) Urokinase-type plasminogen activator receptor (uPAR) was positive on the cell membrane and in cytoplasm of some mononuclear stromal cells (MSCs) and multinucleated giant cells (MGCs); 2) MMP-2 was positive in the cytoplasm and on the cell membrane of almost all of MSCs and some of MGCs. The polar distribution of MMP-2 in the cytoplasm of MGCs was especially obvious; 3) The expression of TIMP-3 of some MSCs and MGCs in GCT was much lower than MMP-2. The positive signal also showed a prominent polarity; 4) After treatment with uPA-ATF, the phosphorylation level of p44 in GCT cultured cells was much higher than the control. Addition of anti-uPAR antibody in the cells remarkably down-regulated the phosphorylation level of p44 as compared with the control group, suggesting that uPA-ATF participates cell signal transduction and this reaction can be inhibited by anti-uPAR antibody; 5) uPA-ATF cell signal pathway up-regulated expression of MMP-2 and TIMP-3, while anti-uPAR antibody down-regulated the expression of MMP-2 and TIMP-3. CONCLUSION: These results demonstrate for the first time that uPA-ATF directly regulates the expression of MMP-2 and TIMP-3 by signal transduction pathway, and the over-expression of MMP-2 and TIMP-3 may play an important role in local osteolysis of GCT. [

OBJECTIVE To explore the mechanism of methylamphetamine (MA) on heart toxicity. METHODS The effects of MA on delayed rectifier potassium current (IK) and action potential (AP) were analyzed in isolated decreased AP from 121.6 to 106.0 mV and delayed the action potential duration (APD), but had no effect on the resting potential. The 10%, 25%, 50%, 75% and 90% of APD (APD10, APD25, APD50, APD75 and APD90)inhibited the membrane potential of rapidly activating delayed rectifier potassium current (IKr) and slowly activating delayed rectifier potassium current (IKs), downward shifted the Ⅰ -Ⅴ curve, but had no effect on the curve shape and could be partly recovered after flushing. The tail current IKr was blocked concentration-dependently after simiarly inhibited by MA. CONCLUSION MA has inhibitory effects on Ik and AP in ventricular myocytes,which may be one of the possible electrophysiological mechanisms of the cardiac damage caused by MA.

Objective To investigate the expression of miR?126, miR?355 and exportin?5 in lung cancer. Methods The cancer tissue and the tissue adjacent to carcinoma of 47 cases of patients with lung cancer was used to detect the expression of miR?126, miR?355 and Exportin?5 by the real?time fluorescence quantitative PCR. Results Significant difference of the expression of miR?126 (t=2.02,P=0.03) and exportin?5 (t=4.62,P<0.01) was observed in lung cancer tissue and tissue adjacent to carcinoma. Mature miR?126 and pri?miR?126 (R=0.309 , P = 0.044) had a negative correlation in the tissue adjacent to carcinoma. In the cancer tissue,miR?126 and MRP (R=0.432, P=0.019), miR?335 and k167 (R=0.410, P=0.033) were positively correlated, however, exportin?5 and TOPO (R=0.357, P=0.045), the pri?miR?126 and drinking (R=0.340, P=0.024), the pri?miR?126 and MRP (R=0.427, P=0.027) had a negative correlation relationship. Conclusion Expression of miR?126 and exportin?5 was decreased in lung cancer tissue, which may contribute to the occurrence and development of lung cancer.

ObjectiveTo explore the changes of degree attribute values and its significance of post-concussion syndrome (PCS) patients with tinnitus by the brain network research method based on graph theory.Methods34 PCS patients were chosen,including 17 PCS patients with bilateral tinnitus (PCS tinnitus group) and 17 PCS patients without tinnitus (PCS non-tinnitus group).Meanwhile,17 healthy individuals with the matched age,gender and educational background were recruited as the control.Degree attribute values of PCS patients with tinnitus were figured out with the brain network research method based on graph theory.Results(1)The degree attribute values of PCS patients without tinnitus at left orbital middle frontal gyrus (3.13±1.07),left thalamus (2.51±1.03),left superior temporal gyrus (3.67±1.31),right anterior cingulate cortex (3.13±1.25),right posterior cingulate cortex (2.13±1.08) and right supramarginal gyrus (4.46±1.35) were reduced compared with the control group (4.41±1.47,3.71±1.08,5.27±2.13,5.51±0.67,5.63±2.16 and 5.64±1.30) (P<0.05).The degree attribute values of PCS patients without tinnitus at left posterior cingulate cortex (5.87±1.06) and left gyrus lingualis (4.67±1.48) increased compared with the control group (4.41±1.46,3.21±1.27) (P<0.05).(2) The degree attribute values of PCS patients with tinnitus at left posterior cingulate cortex (3.37±1.54),left parahippocampal gyrus (3.41±1.62),left amygdala (2.25±1.43),left angular gyrus (4.17±1.02),left superior temporal gyrus (3.25±1.02),right thalamus (2.35±1.34),right Heschl gyri (3.97±1.62),right superior temporal gyrus (3.26±1.22),right cuneus (3.18±1.32) and right lingular lobe (3.26±1.42) were decreased,compared with the control group (4.41±1.46,5.27±2.13,3.71±1.08,5.63±2.61,5.64±1.30,3.43±1.33,5.63±2.16,5.13±1.64,5.51±0.67,4.24±0.63) (P<0.05).The degree attribute values of PCS patients with tinnitus at right posterior cingulate cortex (5.76±1.83),left MPFC (6.08±1.62) and right precuneus (6.08±1.06) were increased,compared with the control group (4.47±1.26,4.41±1.47,4.81±0.62) (P<0.05).(3)The degree attribute values of PCS patients with tinnitus at left MPFC,left amygdale,left parahippocampal gyrus,right Heschl gyri,right superior temporal gyrus,right cuneus and right lingular lobe were decreased,compared with PCS patients without tinnitus (P<0.05).The degree attribute values of PCS patients with tinnitus at right posterior cingulate cortex and left insular lobe increased,compared with PCS patients without tinnitus (P<0.05).ConclusionsPCS patients with tinnitus present the alteration of degree attribute in related brain network structure.The alteration in degree attribute of relevant brain zones in auditory system,limbic system and default network system may be important factors which result in tinnitus of PCS patients.