1.Finite element analysis of slotted-tube stent designs
Chinese Journal of Tissue Engineering Research 2007;11(51):10395-10398
BACKGROUND:Restenosis easily occurs after stent implantation,thus it is worthy optimizing the stent design and evaluating its structural safety.OBJECTIVE:To simulate the deformation of balloon-expandable stainless steel stents by the finite element method,and calculated the radial displacements and stresses after expansion in different designs.DESIGN:A comparative calculated analysis.SETTING:Laboratory of Laser Processing Technology,South China Normal University.MATERIALS:The experiment was carried out in the Laboratory of Laser Processing Technology,South China Normal University in October,2006.The model of slotted-tube stent was used.METHODS:The simulations were carried out to expand a stainless steel stent with 2 mm in outer diameter,10 mm in length and 0.09 mm in strut width.Due to the symmetry of the stent by utilizing the correct boundary conditions,a half model was used to simulate the deformation process.①In stent I,the slot length was 2.0,4.0 and 4.0 mm for a,b and c respectively.In stent Ⅱ,the slot length was 1.5,4.5 and 4.0 mm for a,b and c respectively.In stent Ⅲ,the slot length was 1.8,4.2 and 4.0 mm for a,b and c respectively.Three points(A,B and C)in vary strut were selected to study the displacement during the process of deformation.The pressure applied as a surface load on the inner stent surface was 0.5 Mpa.②The dimensions and radial displacements of the three stent designs in the process of expansion were calculated,and the changes of deformation stresses were observed in the third design.MAIN OUTCOME MEASURES:① The dimensions and radial displacements of the three stent designs in the process of expansion were calculated;②The changes of deformation stresses were observed in the third design.RESULTS:The shape of the expended stent I looked like a dumbbell.The maximum radial displacement of point C obtained is found to be 2.1 mm,and the point B obtained the smallest radial displacement of 0.3 mm in the three defined points.In stent Ⅱ,the maximum radial displacement obtained is found to be point B of 2.1 mm,and the point C obtained the smallest radial displacement of 1.20 mm in lhe three defined point,which obtained a spindly shaped stents.In stent Ⅲ,the maximum radial displacement obtained is found to be point B of 2.2 mm,and the point A obtained the smallest radial displacement of 1.85 mm in the three labeled point,which produce more uniform expansion than the last two stent designs.②In stent Ⅲ,the stresses and the radial displacements achieved as the pressure increased gradually.CONCLUSION:The stress concentrations and the uniformity of the expanded stent can be decreased through optimizing the stent design by finite element method,which can be used in optimizing the stent design and evaluating the structural safety of stents.
2.Analysis of the census results of anus bowel disease in 7102 people
Chinese Journal of Primary Medicine and Pharmacy 2012;19(6):831-832
ObjectiveTo understand anorectal diseases in health in the crowd incidence,clinical and prevention work for anus bowel division provides scientific basis.Methods7102 cases of physical examination for the anus bowel specialized examination,on examination results,statistics,and with the anus bowel disease census results were compared and analyzed.Results7102 cases were detected in anus bowel disease was 4758 cases,the total incidence of 67.0%,including 4119 cases of hemorrhoids,1138 cases of anal papilla,227 cases of rectal polyp,201 cases of anal fissure,113 cases of perianal skin disease,94 cases of anal fistula and one case with rectal cancer.male anus bowel disease(62.3% ) were less than women(73.2% ) ( x2 =93.4,P < 0.01 ),young group of incidence of a disease(59.0% ) in the lower than the elderly group(77.7% ) ( x2 =274.4,P < 0.01 ).ConclusionAnorectal diseases in normal higher incidence in the crowd,carry out standardized anus bowel disease census of disease prevention and cure had relatively positive significance.
3.Comparison of repairing perimembranous ventricular septal defect with continuous and interrupted stitching
Clinical Medicine of China 2010;26(7):707-709
Objective To compare the efficiency of repairing perimembranous ventricular septal defect (VSD) with continuous stitching to that with interrupted stitching. Methods Of the 158 patients with perimembranous VSD ( 54% males) ,102 ( 65% ) patients underwent the repairing of continuous stitching (continuous group) ,and 56 patients underwent interrupted stitching (interrupted group). All the surgeries were performed under hypothermic cardiopulmonary bypass. Results The cardiopulmonary bypass time and aortic cross-clamp times were (31 ±14) mins and (18 ±12) mins in the continuous group, which was significantly less that those of (42 ± 16) mins and (25 ±11) mins in the interrupted group (t =4.49 and 3. 61 .respectively ,P <0. 05) . No case was died. The main complications involved temporary M atrioventricular block (AVB) of two cases (1 case in each group),which disappeared after 1 week. There were two remnants remaining leak (n =2) which was less than 3 mm and automatically cured after 3-6 months. Complete right bundle branch block(CRBBB) occurred in 3 cases in the continuous group and 6 cases in the interrupted group,of which 3 disappeared after 1 month and 2 disappeared after 12 months. The outcome was good in all cases after 1-3 years follow up. Conclusions Continuous stitching showed a shorter cardiopulmonary bypass and aortic cross-clamp times, and reduced the CRBBB.
4.Determination of the Content of Emodin in Qinhuang Houzhen Capsule by HPLC
Traditional Chinese Drug Research & Clinical Pharmacology 1993;0(03):-
Objective To determine the content of emodin in Qinhuang Houzhen Capsule and to provide evidence for its quality criteria.Method A HPLC method was established as follows: Dionex AcclaimTM120 C18 cloumn(4.6? 150 mm,5 ? m),methnol-0.4 % phosphoric acid aqueous solution(85∶ 15) as mobile phase,flow rate at 1.0 mL/min and detection wavelength at 254 nm.Results The average content of emodin in Qinhuang Houzhen Capsule was 0.2057 mg/g,and RSD=4.11 %.Conclusion The content of rhubarb calculated by emodin in 1 g Qinhuang Houzhen Capsule could be affirmed at 0.150 mg/g tentatively.The method is simple,acurate,repeatible,and can be used for the quality control of Qinhuang Houzhen Capsule.
5.Clinical Observation on Yunpi Zhengye Decoction Treating 46 cases of Chronic Functional Constipation due to Deficiency of Both Qi and Yin
International Journal of Traditional Chinese Medicine 2008;30(6):453,456-
Objecfive To investigate the curative effect of Yunpi Zhengye decoction in the treatment of chronic functional constipation due to deficiency of both Qi and Yin.Methods 87 cases in line with the diagnostic criteria of functional constipation were randomly divided into a treatment group(46 cases)and a control group(41 cases).The treatment group was treated with Yunpi Zhengye decoction and the control group was treated with Maren Pills for a therapeutic course of 15 days.Results The cure rate,excellent cure rate and total effective rate in the treatment group Was 71.7%,23.9% and 97.8% respectively,and in the control group was 14.6%,14.6% and 87.8% respectively.The effective rate in the treatment group Was significant better than the control group(P<0.05).Conclusion Yunpi Zhengye decoction has good result in treeing chronic functional constipation due to deficiency of both Qi and Yin.
6.Comparative observation of the effect of etomidate and propofol on circulatory system and the depth of anesthesia in laparoscopic surgery of ectopic pregnancy
Chinese Journal of Biochemical Pharmaceutics 2016;36(9):85-88
Objective To investigate the effects of etomidate and propofol on circulatory system and the depth of anesthesia in laparoscopic surgery of ectopic pregnancy.Methods From January 2014 to January 2015, 40 patients with ectopic pregnancy in our hospital were selected and divided into the etomidate group and propofol group according to the principle of complete random grouping.Patients in the etomidate group received etomidate induced anesthesia, and the patients in the propofol group received propofol induced anesthesia.Hemodynamic parameters and bispectral index(BIS) of two groups were evaluated at 4 time points.The incidence of postoperative nausea and vomiting, chills and bronchospasm were recored.Results There was no significant difference in heart rate (HR),systolic blood pressure (SBP) and diastolic blood pressure(DBP) between the two groups at T0,T2and T3.But at the time of induction(T1), the heart rate of patients in propofol group was significantly lower than that in etomidate group(P<0.05).While T1, compared with etomidate group, the HR and SBP significantly decreased and DBP increased in the propofol group (P<0.05), The HR and SBP at T1of patients in the propofol group and etomidate group decreased significantly and DBP increased when compared with T0(P<0.05).and etomidate group decreased significantly compared with T0 ( P <0.05 ).There were no significant differences in BIS indexes at four time points.However, BIS indexes at T1 ,T2 and T3 were significantly lower than T0 ( P <0.05 ).There was no significant difference in three kinds of complications rates in two groups.Conclusion Etomidate, compared with propofol, can better control the cardiovascular response during induction of anesthesia.Both drugs have a consistent depth of anesthesia.There is no difference in the incidence of complications.Etomidate is more suitable for patients with ectopic pregnancy laparoscopic surgery.
7.The efficacy of inspiring carbogen and low concentration oxygen combined with late course accelerated hyperfraction radiotherapy on esophageal carcinoma
Yanwei SUN ; Jiayun ZHOU ; Yongheng AN
Chinese Journal of Primary Medicine and Pharmacy 2009;16(3):402-404
Objective To evaluate the efficacy of inspiring carbogen and low concentration oxygen combined with late coupe accelerated hyperfraction radiotherapy on esophageal carcinoma.Methods 74 patients with esophageal carcinoma were randomly divided into two groups:the trial group and the centrol group,which consisted of 37 patients respectively.6MV X-ray was employed in the two groups.The schedule of the trial group was as following:conventional radiotherapy of 1.8~2.0Gy per day was employed during the first phase to a total dose of 38~40Gy,followed by late course accelerated hyperfraetion radiotherapy(twice fractions per day,interval between two fractions more than 6 hours,1.3~1.4Gy per fraction,middle total dose of 64.2Gy).Carbogen and low concentraetion oxygen was inspired during the course of radiation.Results 71 patients were enrolled.At the end of radiation at a total dose of 38~40Gy,complete remission rate(CRR)in the trial group was 31%,whereas that in the control group was 19%(P>0.05),when the whole radiotherapy was finished,the CRR was 57%and 31%(P<0.05)respectively,and one month after radiotherapy.the CRR was 71%and 33%respectively(P<0.01).Six months after radiotherapy,the CRR WaLa 74%and 36%respectively(P<0.01).Thelocal controlrate of sixmonthswas 91% and 72% respectively in the two groups(P<0.05).Conclusions Inspiring carbogen and low concentration oxygen combined with late course accelerated hyperfraction radiotherapy may sigllificantly improve short-term efficacy and local control rate in esophageal carcinoma patients in Ⅰ~Ⅲstage.Furthermore,its side effects can be tolerated,and its elongating life time of patients may be prognostic.
8.Biological effects of different fractionated irradiation on pancreas after
Aijie YANG ; Xinjia HE ; Yongheng AN ; Xin WANG
Chinese Journal of Radiological Medicine and Protection 2011;31(6):653-656
Objective To investigate the damages on pancreas after different fractionated irradiation in rats.Methods Eighy healthy adult Wistar rats were randomly divided into four groups with 20 rats in each group as conventional fractionated irradiation group with 2 Gy per fraction to a dose of 12 Gy,hypofractionated radiation group with one fraction of 12 Gy,middle-dose fractionated radiation group with 6 Gy per fraction to a dose of 12 Gy in the interval of 4 days and control group without radiation.Changes in weight,fasting blood glucose and amylase were measured and morphological changes were observed in different periods.Results In the experimental groups,the reduction was observed in fasting glucose at 4 d,reached a minimum of (3.1 ±0.1 ) mmol/L,(LSD-t =20.06 -28.74,P <0.001 ) and the increase of amylase was found after 4th and 7th day,reached a maximum of (84.5 ±6.4) U/L(Dunnett's-t=23.10 -46.10,P < 0.001 ),both more obvious in hypofractionated radiation group than those of conventional fractionated radiation group and middle-dose fractionated radiation group ( LSD-t =8.72-9.71,Dunnett's-t =7.11,P < 0.05 ),however the levels in conventional fractionated radiation group was nearly to middle-dose fractionated radiation group (P > 0.05 ) and became normal at 14 d.Under light microscope,the necrosis of acinarcells was observed in hypofractionated radiation group at 4th d,interstitial fibrogenesis were found at 14 d,the fibrogenesis were found in pancreatic island at 21 d,and the hyperplasia of acinarcells was observed at 42 d.The same changes were found in conventional fractionated radiation group and middle-dose fractionated radiation group,which were gently and lately than those of hypofractionated radiation group.Conclusions Radiation injury is not more serious after middle-dose fractionated radiotherapy than that after conventional fractionated irradiation,when the proper fractional dose and intervals are chosen.
9.Value of low doses of gemcitabine chemotherapy combined with high-low oxygen radiotherapy synchronously for therapy of patients with locally advanced pancreatic cancer
Zhaojun DING ; Yanwei SUN ; Xiping CHEN ; Yongheng AN
Chinese Journal of Pancreatology 2012;12(3):153-155
Objective To evaluate the efficacy and adverse effects of low doses gemcitabine chemotherapy combined with synchronous high-low oxygen radiotherapy in patients with locally advanced pancreatic cancer.Methods Fifty-six patients with locally advanced pancreatic cancer were randomly divided into two groups by envelop method:radio-chemotherapy group or chemotherapy group.Patients in radio-chmotherapy group were treated with low doses of gemcitabine chemotherapy ( 600 mg/m2 ) combined with high-low oxygen radiotherapy synchronously,paients in chmotherapy group were treated with full doses of gemcitabine chemotherapy ( 1000 mg/m2).The short-term effect,distant metastasis rate,clinical benefit rate,survival rate and adverse events of two groups were observed.Results There was one patient achievedcomplete relief and 15 patients achieved partial relief in radio-chemotherapy group with an overall effective rate of 66.7% (16/24) ; there were 9 patients achieved partial relief in chemotherapy group with an overall effective rate of 36.0% (9/25),the difference between the two groups was statistically significant (X2 =4.6082,P =0.0318 ).The clinical benefit rates were 83.3 % ( 20/24 ) and 60% ( 15/25 ),respectively,the difference between the two groups was not statistically significant ( P =0.070).The distant metastasis rates were 66.7%(16/24) and 72% (18/25),respectively,the difference between the two groups was not statistically significant (P =0.6855).The 12,24 months survival rates were 62.5% vs 32%,37.5% vs 12%,the difference between the two groups was statistically significant ( P =0.0325,0.0380).The incidence of serious adverse events was 45.8% and 4 0 % without statistical difference.Conclusions Low doses of gemcitabine chemotherapy combined with high-low oxygen radiotherapy synchronously is better than full doses of gemcitabine chemotherapy with regard to total effective rates and 12,24 months survival rates,with no obvious increase in the incidence of serious adverse events.
10.Simultaneous Determination of Six Kinds of Phthalic Acid Esters in Human Serum by Gas Chromatography-Mass
Chunying LIANG ; Hongmei DENG ; Yongheng CHEN
Journal of Environment and Health 2007;0(11):-
Objective To establish a method to determine six kinds of PAEs in human serum simultaneously,and on this basis to understand the level of PAEs in human body.Methods Ultrasonic extraction,gas chromatography-mass spectrometry-selected ion monitoring(GC-MS-SIM) detection and quantitative analysis based on internal standard were used to detect six kinds of PAEs in human serum simultaneously.Finally this method was used in fifty human serum samples.Results The results showed that this method had a good linear relation in the range from 10 to 1 000 ng/ml,and the correlation coefficients of standard curve were higher than 0.999.The average recovery rate and the relative standard deviation(RSD,n=6) of the target compounds in standard-addition blank was 94.5% and 4.4% respectively,the lower limits of detection for DEP,DMP,DBP,BBP,DEHP,DNOP were 0.31,0.85,0.90,0.63,0.88,0.41 ng/ml respectively,and the recovery rates of all samples ranged from 67.98% to 110.8%.Conclusion This method has good recovery rate,reproducibility,lower limit of detection and can be used for the determination of many kinds of PAEs substances in human serum.