1.Effects of film thickness on the phase composition and microstructure properties of micro-arc oxidation coating.
Rongrong NIE ; Feng ZHU ; Liru SHEN ; Zhiqing CHEN
Journal of Biomedical Engineering 2010;27(2):354-357
In this study, we obtained the TiO2 films with different thickness by micro-are oxidation (MAO) on commercially available pure titanium. By altering the duration time, we got the films 5 microm, 10 microm, and 20 microm in thickness, respectively. XRD and SEM were employed to characterize the phase, composition and microstructure of the films. The MAO film, which was about 5 microm thick, was porous and even with the pore size about 1 microm. No other crystalline phase except anatase was detected by XRD. The film, which was 10 microm thick, was similar to the former. The pores were well separated and homogeneously distributed over the surface. The XRD pattern indicated that the film was composed of anatase and a minor amount of rutile, whereas the pore size of 20 microm film was about 4-6 microm and was bigger than the others. Furthermore, the small cracks were easy to observe. XRD pattern showed that the Ti peak was significantly reduced and new Ca, P, O containing compound was formed in addition to rutile and anatase with the film thickness increasing. There were significant differences in regard to surface roughness of the three groups. These findings suggest that the film thickness has an intense effect on the quality of the MAO coating. By changing the film thickness, we can extensively change the composition, structure and chemical properties of the surface layer on titanium.
Coated Materials, Biocompatible
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chemistry
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Oxidation-Reduction
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Porosity
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Surface Properties
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Titanium
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chemistry
2.Simultaneous determination of peimine and peiminine in Xiaoer Baotaikang gran-ules by HPLC-ELSD
Liru SHEN ; Ruihong LI ; Tailiang WANG
Journal of Pharmaceutical Practice 2016;34(4):351-353
Objective To develop a new high performance liquid chromatography (HPLC ) coupled with Evaporative Light Scattering Detector (ELSD) method for simultaneous determination of two indicative components (peimine and peimi-nine) in Xiaoer Baotaikang granules .Methods The analysis was performed on a Thermo C18 column (250 mm × 4 .6 mm , 5 μm) by using a mobile phase consisted of acetonitrile-water and diethylamine (65 ∶ 35 ∶ 0 .03) ,and the flow rate was 1 .0 ml/min;ELSD parameters :the temperature of drift tube was 85 ℃ and the carrier gas flow rate was 2 .2 L/min .Results The linear ranges of peimine and peiminine were 0 .586~5 .860 μg (r=0 .999 6) and 0 .564~5 .640 μg (r=0 .999 9) ,respec-tively .The average recovery rate for peimine and peiminine was 99 .44% (RSD was 0 .7% ) and 98 .56% (RSD was 1 .0% ) , respectively .Conclusions The method is sample ,accurate and reproducible ,which could be used for the quality control of Xiao-er Bao taikang g ranules .
3.Bone tissue engineering scaffolds.
Liru FANG ; Wenjian WENG ; Ge SHEN ; Gaorong HAN ; J D SANTOS ; Peiyi DU
Journal of Biomedical Engineering 2003;20(1):148-152
Bone tissue engineering may provide an alternative to the repairs to skeletal defects resulting from disease, trauma or surgery. Scaffold has played an important role in bone tissue engineering, which functions as the architecture for bone in growth. In this paper, the authors gave a brief introduction about the requirement of bone tissue engineering scaffold, the key of the design of scaffolds and the current research on this subject.
Biodegradation, Environmental
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Bioprosthesis
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Bone Substitutes
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chemistry
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metabolism
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Mechanics
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Surface Properties
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Tissue Engineering
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methods
4.Prognostic factors of salvage radiotherapy after radical prostatectomy
Yang LIU ; Feng WEN ; Yali SHEN ; Qiwen PAN ; Jinxia HE ; Lixin MAI ; Hao ZENG ; Jianming GAO ; Xiang LI ; Zhiping LI ; Yonghong LI ; Xin WANG ; Liru HE ; Qiang WEI ; Fangjian ZHOU
Chinese Journal of Urology 2021;42(9):650-655
Objective:To investigate the prognosis after salvage radiotherapy with or without hormone therapy for prostate cancer.Methods:From May 2014 to December 2020, 248 patients undergoing salvage radiotherapy due to prostate-specific antigen (PSA)persistence or biochemical progression after radical prostatectomy at Sun Yat-sen University Cancer Center (n=157) and West China Hospital, Sichuan University (n=91) were analyzed. Median age was 66 (45-78) years old. Median PSA was 23.50 (0.18-845.00) ng/ml. The number of PSA persistence and biochemical progression were 143 (59%) and 105 (42%). The number of pT 2, pT 3a, pT 3b, pT 4, and unknown T stage was 99, 49, 78, 15 and 7 cases.The number of N 0, N 1 and unknown N stage was 153, 44 and 51 cases. 165 cases had positive surgical margin. Gleason score of 6, 7, 8, >8 score and unknown was in 12, 104, 34, 90 and 8 patients. Early and late salvage radiotherapy was performed in 117 and 131 patients, and 70 patients (28%) were CRPC. Hormone therapy was used combined with radiotherapy in 182 patients (73%). PSA decline after radiotherapy was compared with Chi-squre test. Kaplan-Meier method and log-rank test were used to compare progression free-survival (PFS)after radiotherapy. Univariate and multivariate analyses of PFS were performed using Cox proportional hazards model. Early salvage radiotherapy was defined as PSA≤0.5 ng/ml before radiotherapy, and late salvage radiotherapy was defined as PSA>0.5ng/ml. Results:PSA response (PSA decline ≥50%) rate was 94% (233/248), and 82% (203/248) patients had PSA decline ≥ 90%. Twelve (5%) patients had rising PSA after completing radiotherapy, but only 4 (2%) had real progression. The median PFS was 69 months (95% CI 68-70), and 3-year and 5-year PFS rate were 80% and 67%. PFS of PSA persistence and biochemical progression were similar ( HR =0.71, 95% CI 0.37-1.37, P=0.311). Compared with late salvage radiotherapy, early salvage radiotherapy had better PFS [69 (95% CI 68-70) vs. 59 (95% CI 44-74) months, P<0.001]. Compared with hormone sensitive, castration-resistant was associated with worse PFS (5-year PFS rate 74% vs. 51%, P<0.001). In multivariate analysis, Gleason score>8, castration-resistant and late salvage radiotherapy were unfavorable prognostic factors. Conclusions:In patients receiving salvage radiotherapy with or without hormone therapy for PSA persistence and biochemical progression after radical prostatectomy, high PSA level before radiotherapy and castration resistant is associated with poor prognosis.