objective: To study the properties of keepers treated with different methods. Methods: Eighteen Z 3 magnetic attachments were divided into three groups at random. Cobalt chromium alloy was used for root cap. The keepers in the first group were cast to the caps, those in the second group were welded to the caps by Nd:YAG laser welding apparatus. Keepers in the third group were untreated. Universal testing machine was adopted to measure the breakaway retention of the attachments. The roughness of keeper surfaces was measured by roughness tester. Results: No statistical difference was observed as to the breakaway retention between magnetic attachments and laser welded coping keeper or between those and cast coping keepers. But retention of the keepers in the two groups was slightly lower than that of untreated keepers. Defects of pits were found on the surfaces of the cast coping keepers. The surface smoothness of the cast coping keepers was inferior to that of the laser welded coping keepers. Conclusion: Laser welded keepers and cast coping keepers can meet clinical demands for the use of magnetic attachments.

OBJECTIVE:To study the mechanism of Cassia obtusifolia L in decreasing blood-lipid.METHODS:Primary cultures of rat hepatocytes in vitro were used to determine the concentrations of proteins in hepatocytes by the method of Folin-phenol reagent and to assay the cholesterol synthesis from 14 C-acetate with liquid scintillation count.RESULTS:Ex?tract of Cassia obtusifolia L inhibited cholesterol synthesis from 14 C-acetate,but cassiaside B didn't affect cholesterol synthe?sis.CONCLUSION:The mechanism of extract of Cassia obtusifolia L in decreasing blood-lipid may result from inhibition of cholesterol synthesis,but inhibiting cholesterol synthesis may be not the main approach of cassiaside B in decreasing blood-lipid.

Objective To explore the relationship between angiotensin I-converting enzyme(ACE)gene I/D and angiotensin Ⅱ type 1 receptor(AT1R)gene A1166C polymorphisms and cereral infarction(CI).Methods ACE and AT1R genotypes were investigated with the method of PCR-RLFP in 88 patients with CI and compared with 90 age-matched population controls.Results AC genotypic frequency(31.8%)and C allele frequency(15.9%)of AT1R gene in CI group were significently higher than those in control group(11.1%,5.6%)(all P0.05).Conclusions The polymorphism of AT1R A1166C is related to the incidence of CI.There are synergistic effects of ACE DD genotype and AT1R gene A1166C polymorphisms on the risk of CI.

Objective To explore the relationship between angiotensin Ⅱ type 1 receptor (AT1R) gene polymorphisms and cerebrovascular disease (CVD).Methods The 104 patients with CVD and 98 healthy individuals were detected the AT1R genotypes polymorphisms by restriction fragment length polymorphism in order to analysis.Results CC genotype was not found both in CVD and control group. In CVD group, genotypic frequency of AA was 40.4% and AC was 59.6%. The allele frequency of A was 70.1% and C was 29.9%. In control group, genotypic frequency of AA was 91.8% and AC was 8.1%. The allele frequency of A was 95.9% and C was 4.1%. AT1R polymorphism revealed there was significant difference between the genotype and allelic distribution in CVD patients and those of in controls (all P

Objective To study the relationship between elevated serum level of immunoglobulin A (IgA) and other abnormality in immunological parameters in patients with primary Sjogren's syndrome (pSS)and those with viscera involvement based on determinations of serologic,other laboratory and clinical features.Methods Serum IgA level of 108 patients with pSS,seven males and 101 females with an age of 30～78 years and length of disease course of 0.2～20.0 years,was detected by turbidimetry.Clinical and laboratory parameters in patients were compared between different groups.Remits Elevated serum IgA level was found in 48 (44.4%) of 108 patients with pSS.Elevated erythrocyte sedimentation rate(ESR) was found in 91.7 percent of those with elevated sertum IgA and 63.3 percent in those with normal IgA(P<0.05).Serum positivity of rheumatoid factor(RF) was significantly higher in those with elevated serum IgA (70.8%)than those with normal IgA (48.3%,P<0.05).Pulmonary interstitial fibrosis could be found in 22.9 percent of those with elevated serum IgA,and in 8.3 percent of those with normal IgA(P<0.05).Occurrences of primary biliary cirrhosis and autoimmune hepatitis were higher in those with elevated serum IgA than in those with normal IgA,but not reaching statistical significance.Conclusion Serum IgA level misht play an important role in occurrence and development of pSS,and could be used as an indicator reflecting activity and severity of the disease,as well.

Objective To explore the sensitivity of antibodies against RF,APF,AKA,anti-CCP in rheumatoid arthritis (RA) and analyze the relationship between these autoantibodies in RA.MethodsFive hundreds of RA patients were studied.Immunoturbidmetry was used to measure the RF-IgM.The enzyme-linked immunosorbent assay (ELISA) was used to measure the HRF-IgG,HRF-IgA and anti-CCP.Indirect immunofluorescence was used to measure the APF and AKA.ResultsThe seropositive rates of RF-IgM,anti-CCP,APF,HRF-IgG,AKA and HRF-IgA were 78.0%,70.8%,51.8%,48.4%,45.0% and 20.0% respectively.RF-IgM could not be detected in 110 patients while the seropositive rates of anti-CCP,APF,AKA,HRF-IgG and HRF-IgA were 41.8%,27.3%,22.7%,15.5% and 1.8% respectively.Anti-CCP could not be detected in 146 patients while the seropositive rates of RF-IgM,HRF-IgG,APF,AKA and HRF-IgA were 56.8%,24.7%,16.4%,8.9% and 7.5% respectively.The combined sensitivities of RF-IgM anti-CCP and APF were higher than others.The seropositive rates were 88.6%.ConclusionsRF-IgM and anti-CCP are sensitive antibodies for diagnosis of RA.Combinations RF-IgM with anti-CCP can significantly improve the sensitivity of diagnosis of RA.

The dissolution of nickel from nitinol alloy under different extraction conditions was investigated when biological tests of nitinol medical devices were carried out. It discussed the equivalence of these extraction conditions and found the best extraction conditions. In the experiment, two brands of nitinol were chosen and extracted under different extraction conditions according to GB/T 16886-12. Plasma emission spectrometer was used to analyse the concentration of nickel in extract liquid. The results show that there is no equivalence among these extraction conditions for nitinol materials. And it is suggested that (37 +/- 1) degree C, (72 +/- 2) h could be used as normal extraction condition and (70 +/- 2) degrees C, (24 +/- 2) h as accelerated extraction condition.
Alloys ; chemistry ; Biocompatible Materials ; Materials Testing ; Nickel ; chemistry ; Temperature ; Titanium

Objective To discuss the long term clinical effect of ileal orthotropic neobladder.Methods From 1991 to 1998,79 patients,mean age 55(41～75)years,male 74,female 6,were followed up.The serum creatinine and urea,electrolytes,blood routine,B ultrasonic scan of the neobladder residual urine and IVU or MRU of the patients were followed up.The max transverse diameter of renal pelvis and the max verticaI/level diameter of neobladder were measured in 5,10 to 14,15 years of postoperative when IVU or MRU.All results of different time were compared by the multiple comparisons.The local or distant cancer recurrence and the complications of the operation Were evaluated. Results Sixty-four cases,58 male,6 famle,were long term followed up:mean time was 167 (range,121～216)months.Seven cases died of other diseases.Seven cases had pelvic recarrence.Two cases had urethral recurrence.Three cases died of tumor metastasis.One case had ureter recurrence.Forty-eight patients were alive more than 10 years.The value of the serum creatinine,urea,electrolytes and bloods routine of the patients were normal after 5,10 to 14 and 15 vears postoperative (P＞0.05).The max transverse diameter of the renal pelvis in 5,10 to 14 and 15 years Dostoperative were 14.0 mm,14.1 mm and 13.7 mm,respectively,P＞0.05.The max vertical/level diameter of the neobladder in 5,10 to 14,15 years of postoperative were 110.4 mm/90.4 mm,111.5 mm/95.3mm and 127.0 mm/97.0 mm,respectively,P＞0.05.The residual urine of 5 cases was more than 50 ml and had not increased during follow up.Eight cases with neobladder stone were cured by the intracavitary lithothrypsis.Two cases with uretheral stricture were cured by the intracavitary therapy.Twelve cases of 14 cases with inguinal hernia were cured by reoperation,2 cases accepted conservative treatment.Only 17 cases had no complication involve of the cancer and the operation. Conclusion The upper urinary tract and neobladder of the ileal orthotopic neobladder could be stable for long time,the cure rate of tumor is satisfactory and the lifetime follow up is necessary.

Objective:To analyze the correlation between the monitor units and pass rate of plan dose verification in the volumetric intensity modulated arc therapy (VMAT) plan.Methods:VMAT plans for 20 patients with nasopharyngeal carcinoma (NPC) and 30 patients with cervical cancer who underwent radiotherapy at Liuzhou Workers' Hospital from January to October 2020 were retrospectively chosen. The Detector 1500 array and Octavius 4D phantom from German PTW company were used for dose measurement. The pass rates of dose verification of relevant plans were analyzed under the conditions of 3%/2 mm and 2%/2 mm. The correlation between the monitor units and pass rate of plan dose verification in VMAT plans was assessed by Pearson's bivariate correlation analysis.Results:Under the condition of 3%/2 mm, the correlation coefficients between the monitor units and gamma pass rate were -0.873 ( P<0.001), -0.800 ( P<0.001), -0.781 ( P<0.001), -0.493 ( P=0.006) for NPC_1Arc, NPC_2Arc, NPC_1Arc+NPC_2Arc and Cervix_2Arc, respectively. Under the condition of 2%/2 mm, the correlation coefficients between the monitor units and gamma pass rate were -0.842 ( P<0.001), -0.770 ( P<0.001), -0.748 ( P<0.001) and -0.531 ( P=0.003) for NPC_1Arc, NPC_2Arc, NPC_1Arc+NPC_2Arc and Cervix_2Arc, respectively. Conclusion:Significant negative correlation can be observed between the monitor units and plan dose verification pass rate in VMAT plan.