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1.
Статья в Китайский | WPRIM | ID: wpr-1026254

Реферат

Objective To observe the value of preoperative CT enterography(CTE)for predicting the necessity of enterectomy in ovarian cancer(OC)patients for achieving optimal debulking surgery(ODS).Methods Preoperative CTE data of 49 patients with pathologically confirmed OC were retrospectively analyzed,including 13 cases received neoadjuvant chemotherapy(NACT)and 36 cases did not.The length(L)and circumference(C)of muscular involvement shown on CTE were taken as criteria for judging the necessity of enterectomy in OC patients([degree 0:no muscular involvement,degree 1:L<3.0 cm and C<1/3,degree 2:L≥3.0 cm[A]or C≥1/3[B]).The patients were followed up for at least 1 year after surgery,and the actual operation results were recorded to estimate the ideal surgical strategy.The consistency of CTE evaluated necessity of enterectomy and the ideal surgical strategy was analyzed.Results For patients not undergoing NACT,according to degree 2 A or B showed on CTE,predicted results had excellent agreement with the ideal surgical strategy(Kappa=0.852,P<0.001),while those according to degree 1 or 2,2 A,2 B were all in good agreement with the ideal surgical strategy(Kappa=0.684-0.771,all P<0.001).For patients undergoing NACT,the predicted results of degree 2 muscular involvement showed on CTE before NACT had excellent consistencies with the ideal surgical strategy(all Kappa=0.806,all P=0.003).The predicted results of degree 2 muscular involvement showed on CTE after NACT had moderate consistencies with the ideal surgical strategy(all Kappa=0.581,all P=0.021).Conclusion Preoperative CTE could be used to predict the necessity of enterectomy in OC patients for achieving ODS.

2.
Acta Anatomica Sinica ; (6): 244-248, 2023.
Статья в Китайский | WPRIM | ID: wpr-1015231

Реферат

Objective To design and validate a novel surgical guide for retrieval of foreign body in jaw. Methods Firstly, a surgical guide based on cone beam computed tomography and trephine technique was designed to remove broken dental instrument fragments. Its feasibility and accuracy were assessed by removing broken dental instrument in goat mandible, and then it was successfully applied in clinical cases. The linear and angular discrepancies between actual and planned columnar bone with imaginary fragment was analyzed. The euclidean distance was measured at the hex and apex of the columnar bone and the angle of axis deviation was also calculated. We obtained seven parameters (cdh, cda, hdh, hda, vdh, vda, and ad) to describe deviations. Results Mean central deviation at the hex and apex was (0.51 ± 0.14) mm and (0.62 ± 0.19) mm, respectively. Accompanying mean values were as follow: horizontal deviation at the hex was (0.48 ± 0.16) mm, horizontal deviation at the apex was (0.52 ± 0.22) mm, vertical deviation at the hex was (0.17 ± 0.09) mm, vertical deviation at the apex was (0.29 ± 0.13) mm, and angular deviation of (5.38 ± 3.43) degrees. In a clinical case, the guide successfully located and removed the fracture file. Conclusion This study reveals that this kind novel surgical guide could aid to locate and remove the foreign body in jaw.

3.
Статья в Китайский | WPRIM | ID: wpr-989836

Реферат

Objective:To explore the factors influencing the clinical outcome of complex high-risk indicated patients percutaneous coronary intervention (CHIP-PCI) assisted by extracorporeal membrane oxygenation (ECMO).Methods:The clinical data of patients with CHIP-PCI assisted by ECMO in the First Affiliated Hospital of Zhengzhou University from April 2018 to April 2022 were retrospectively collected and analyzed. Patients were divided into the survival and death groups according to the in-hospital survival status. The baseline characteristic, the results of coronary angiography, and the use of ECMO, blood products and drug were compared between the two groups. The 24-h rate of change of biochemical test indicators after the use of ECMO were calculated and the univariate analysis was analyzed using rank sum test. According to the univariate analysis, the variables ( P<0.05) were included in multivariate logistic regression to analyze the factors affecting the clinical outcomes of patients. Results:A total of 67 CHIP patients who completed PCI with ECMO were included. In the survival group ( n=36), the duration of ECMO treatment was 59 (41, 87) h, 9 cases received continuous renal replacement therapy, and 11 cases received IABP. In the death group ( n=31), the duration of ECMO treatment was 31 (19, 80) h, 12 cases received continuous renal replacement therapy and10 cases received IABP. The proportion of patients with chronic total occlusion lesions (CTOs) in the survival group was lower than that in the death group, the duration of ECMO of the survival group was longer than that of the death group ( P<0.05). Multivariate logistic regression analysis showed that 24-h lactate change rate ( OR=2.864, 95% CI: 1.185-6.918, P=0.019), 24-h eGFR change rate ( OR=0.050, 95% CI: 0.003-0.871, P=0.040), 24-h D-dimer change rate ( OR=1.497, 95% CI: 1.044-2.146, P=0.028) and 24-h direct bilirubin change rate ( OR=2.617, 95% CI: 1.121-6.111, P=0.026) were associated with in-hospital mortality. Conclusions:Within 24 h after CHIP-PCI assisted by ECMO, the rapid decline in lactic acid, D-dimer and direct bilirubin, and the rapid recovery of eGFR, are associated with the decreased risk of hospital mortality from CHIP.

4.
Статья в Китайский | WPRIM | ID: wpr-954297

Реферат

Objective:To investigate the effects of different chemotherapy dose intensity on the short-term efficacy and adverse reactions of patients with advanced colon cancer.Methods:A real-world database of patients with advanced colon cancer in Wangjing Hospital of China Academy of Chinese Medical Sciences and China-Japan Friendship Hospital from January 2017 to December 2020 was established, including 105 patients treated with the same chemotherapy regimen for two consecutive cycles. The patients were grouped according to the average relative dose intensity (ARDI) of chemotherapy, and the population differences, treatment regimens, short-term efficacy and adverse reactions of different chemotherapy dose intensities were evaluated. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of ARDI for short-term efficacy.Results:There were 31 patients in the high dose intensity group (ARDI≥80%) , 34 patients in the medium dose intensity group (80%<ARDI<60%) , and 40 patients in the low dose intensity group (ARDI≤60%) . There were statistically significant differences in age ( χ2=13.20, P=0.010) and Karnofsky functional status (KPS) score ( χ2=7.99, P=0.008) among the high dose intensity group, medium dose intensity group and low dose intensity group. Compared with the low dose intensity group, the proportion of young and middle-aged patients in the high dose intensity group was higher, and the proportion of elderly patients was lower ( χ2=12.63, P=0.002) . Compared with the medium dose intensity group, the proportion of patients with KPS score ≥60 was lower and the proportion of patients with KPS score <60 was higher in the low dose intensity group ( P=0.013) . There was a statistically significant difference in the application of chemotherapy regimen among the three groups ( χ2=22.88, P=0.027) , and there was a statistically significant difference in the application of chemotherapy regimen between the high dose intensity group and low dose intensity group ( χ2=16.25, P=0.009) . The proportions of the high, medium and low dose intensity groups receiving combined chemotherapy were 96.77% (30/31) , 82.35% (28/34) and 80.00% (32/40) respectively. The incidences of chemotherapy drug reduction in the high, medium and low dose intensity groups were 93.55% (29/31) , 100% (34/34) and 100% (40/40) respectively, and the incidences of chemotherapy delay were 41.94% (13/31) , 79.41% (27/34) and 87.50% (35/40) respectively. The objective response rates of the high, medium and low dose intensity groups were 22.58% (7/31) , 14.71% (5/34) and 2.50% (1/40) respectively, with a statistically significant difference ( χ2=7.11, P=0.027) . The disease control rates of the high, medium and low dose intensity groups were 93.55% (29/31) , 91.18% (31/34) and 87.50% (35/40) respectively, with no statistically significant difference ( χ2=0.75, P=0.714) . The differences of carcinoembryonic antigen before and after treatment in the high, medium and low dose intensity groups were 2.09, 0.47 and -0.72 ng/ml respectively, with a statistically significant difference ( χ2=10.09, P=0.006) . Compared with the low dose intensity group, the difference of carcinoembryonic antigen before and after treatment in the high dose intensity group was greater ( χ2=23.12, P=0.005) . The differences of carbohydrate antigen 199 before and after treatment in the high, medium and low dose intensity groups were 2.30, 0.00 and -0.21 U/ml respectively, with a statistically significant different ( χ2=8.85, P=0.012) . Compared with the low dose intensity group, the difference of carbohydrate antigen 199 before and after treatment in the high dose intensity group was greater ( χ2=21.40, P=0.010) . No adverse reactions above grade 3 occurred in the three groups, and the safety was good. The most common adverse reactions were anemia (61.90%, 65/105) , leucopenia (39.05%, 41/105) , neutropenia (29.52%, 31/105) and nausea (36.19%, 38/105) . There were no statistically significant differences in the incidences of adverse reactions among the high, medium and low dose intensity groups (all P>0.05) . ROC curve analysis found that the area under the curve predicting objective response was 0.70, the sensitivity was 92.30%, and the specificity was 52.10% when the chemotherapy ARDI threshold was 64%. Conclusion:In the real world, colon cancer patients receiving high dose intensive chemotherapy have better objective response rate, and tumor markers decreased significantly. The baseline status of colon cancer patients receiving low dose intensive chemotherapy is poor, but there is no statistically significant difference in disease control rate between patients receiving low dose intensive chemotherapy and patients receiving high dose intensive chemotherapy, and the adverse reactions are controllable.

5.
Статья в Китайский | WPRIM | ID: wpr-802069

Реферат

Objective: To investigate the inhibitory effect of capsaicin on the growth of breast cancer MDA-MB-231 cells transplanted tumour in nude mice and its possible molecular mechanism. Method: Transplanted tumor model of breast cancer MDA-MB-231 cells in nude mice were established. Then the tumor-bearing mice were randomly divided into 4 groups:model group, and low, medium and high-dose capsaicin groups (5, 10, 20 mg·kg-1). Mice of low, medium and high-dose capsaicin groups (5, 10, 20 mg·kg-1) were intraperitoneally injected with the corresponding dose of capsaicin, and the model group was injected with the same volume of phosphate buffer saline (PBS), once every 3 days, for a total of 8 times in succession. Body weight of mice and transplantation tumor volume were measured before each injection of capsaicin. Mice of each group were put to death 24 h after the last administration, and then the tumor volume, mass and the tumor inhibitory rate were calculated. The protein expression levels of high mobility group box 1 (HMGB1) and Toll-like receptors 4(TLR4) were measured by immunohistochemistry and Western blot. Result: No significant difference was observed between each group in body weight. However, compared with the model group, capsaicin (5, 10, 20 mg·kg-1) remarkably inhibited the tumor volume and mass (PPP-1) also markedly inhibited the protein expression levels of HMGB1 and TLR4 (PConclusion: Capsaicin remarkably inhibits the growth of breast cancer MDA-MB-231 cells transplanted tumour in nude mice, and the possible mechanism may be related to the down-regulation of HMGB1 and TLR4 at the protein level.

6.
Статья в Китайский | WPRIM | ID: wpr-802071

Реферат

Objective: To investigate the effect of capsaicin on the migration and invasion of human breast cancer MCF-7 cells and the underlying molecular mechanism. Method: Three capsaicin intervention groups of different concentrations (25, 50, 75 μmol·L-1) and a blank group were set up. After MCF-7 cells were treated with different concentrations of capsaicin (25, 50, 75 μmol·L-1) for 24 h, the cell migration and invasion abilities were assessed by Transwell migration and invasion assay, respectively. Meanwhile, the mRNA level of silent information regulator 2 homolog 1 (SIRT1) and DNA polymerase δ catalytic subunit p125 encoding gene POLD1 (POLD1) were detected by Real-time polymerase chain reaction (Real-time PCR). The protein levels of SIRT1 and DNA polymerase δ catalytic subunit p125 (p125) were detected by Western blot. Result: Compared with the blank group, the number of transmembrane cells was significantly reduced, and the mobility was significantly decreased (P-1) in MCF-7 cells for 24 h. Capsaicin (25, 50, 75 μmol·L-1) significantly down-regulated the mRNA and protein expressions of SIRT1 (P-1) in MCF-7 cells for 24 h. Furthermore, capsaicin (25, 50, 75 μmol·L-1) also significantly down-regulated the mRNA expression of POLD1 and the protein expression of p125 (P-1) in MCF-7 cells for 24 h. Conclusion: Capsaicin remarkably inhibits the cell migration and invasion of breast cancer MCF-7 cells, and the possible mechanism may be related to the down-regulation of SIRT1 and POLD1 mRNA expression levels and SIRT1 and p125 protein expression levels.

7.
Статья в Китайский | WPRIM | ID: wpr-772463

Реферат

OBJECTIVE@#This work aims to analyze the mechanical properties and biocompatibility of porous titanium (Ti) implants fabricated by selective laser sintering (SLS) and investigate the promotion of osseointegration by porous titanium implant combined with chitosan (CS)/hydroxyapatite(HA) composite coating.@*METHODS@#Ti6Al4V specimens were prepared, and CS/HA composite coating was fabricated on the surface of a portion of the specimens. The mechanical properties of the samples were observed by scanning electron microscope. MC3T3-E1 cells were cultured in vitro, and their biological properties in vitro were analyzed using live and dead viability cell staining method, methyl thiazolyl tetrazolium (MTT) staining, and alkaline phosphatase (ALP) level detection. The thread implant specimens were implanted in the femoral condyle of rabbits, and biological performance was evaluated in vivo.@*RESULTS@#Quasi-elastic gradient of porous specimens decreased with increasing porosity, and the quasi-elastic gradient were close to cortical and cancellous bone when the porosities were 30% and 70%. The specimens showed good biocompatibility. Combined with CS/HA coating, the implants promoted the proliferation and differentiation of MC3T3-E1 cells and facilitated the entry of bone tissue into pores and good osteogenesis.@*CONCLUSIONS@#The porous titanium implant exhibited favorable mechanical properties and biocompatibility. Combined with CS/HA coating, the implant exhibited bone inducibility, which leads to stable osteogenesis.


Тема - темы
Animals , Rabbits , Durapatite , Lasers , Materials Testing , Microscopy, Electron, Scanning , Osseointegration , Porosity , Prostheses and Implants , Surface Properties , Titanium
8.
Zhongguo Zhong Yao Za Zhi ; (24): 3058-3063, 2018.
Статья в Китайский | WPRIM | ID: wpr-687346

Реферат

In this study, on aspects of the nociceptive, anxiety and depressive syndromes in neuropathic pain (NP), the effects of dihydroartemisinine (DHA), artesunate (ART) and artemether (ARTN) (40 mg·kg⁻¹) were analyzed in the spinal cord ligation (SNL) mice. Clinical equivalent dose of the first-line drug for NP, pregabalin (PGB, 25 mg·kg⁻¹) and amitriptyline (ARP, 20 mg·kg⁻¹), were used as positive controls. General, from day 7 to 14, significant remissions of the nociceptive, anxiety and depressive behaviors were achieved by DHA, ART and ARTN separately. Moreover, on day 14, on aspects of the nociceptive behaviors, analyzed 1.5 h after the gavage administration, no significant difference between the shamed mice and mice administrated with DHA, ART and ARTN was detected; analyzed 3 h after the gavage, significant decreases of pain thresholds in ARTN, but not in DHA nor ART group, were detected as compared with thresholds measured 1.5 h; analyzed 24 h after gavage, pain thresholds in DHA, ART and ARTN were still higher than PGB, in spite of the significant decreases as compared to Sham group. On aspects of the anxiety and depressive behaviors, no significant difference was detected between the shamed mice and mice administrated with DHA nor ART. However, differences still remained between the shamed ones and ones administrated with ARTN. Preliminarily, the effects of DHA, ART and ARTN were consolidated in SNL mice. On aspects of the duration of analgesic effects and the control of negative emotion, ART and ARTN were proven more favorable than ARTN.

9.
Zhongguo dangdai erke zazhi ; Zhongguo dangdai erke zazhi;(12): 790-795, 2017.
Статья в Китайский | WPRIM | ID: wpr-297207

Реферат

<p><b>OBJECTIVE</b>To study the clinical characteristics of urticaria in children versus adults, and to provide reference for the etiological analysis, disease evaluation, and treatment of urticaria in children.</p><p><b>METHODS</b>The clinical data of 2 411 patients with urticaria who visited the Department of Dermatology at Xiangya Hospital of Central South University from January 2013 to May 2017 were collected to study their socio-demographic characteristics. The clinical characteristics of urticaria were compared between the 68 children and 672 adults of the 740 patients with complete follow-up data.</p><p><b>RESULTS</b>Among the 411 pediatric patients, 314 (76.4%) had acute urticaria; among the 2 000 adult patients, 896 (44.8%) had chronic spontaneous urticaria. The causes of acute urticaria in children included infection (41%, 16/39). The accompanying symptoms of acute urticaria in children mainly included abdominal pain and diarrhea (44%, 17/39), while those in adults mainly included chest distress and shortness of breath (32%, 11/34). Compared with the adult patients, the pediatric patients had significantly lower chronic urticaria activity scores before and after treatment (P<0.05), a significantly higher rate of response to second-generation antihistamines (82.1% vs 62.2%; P<0.05), and a significantly higher proportion of individuals with a personal and family history of urticaria (P<0.05).</p><p><b>CONCLUSIONS</b>Acute urticaria is more commonly seen than chronic urticaria in children with urticaria, and the main accompanying symptoms are abdominal pain and diarrhea, which are different from adults with urticaria. Chronic urticaria has a better treatment outcome in children than in adults. The most frequently seen cause of acute urticaria is infection in children. Atopic children may be susceptible to urticaria.</p>


Тема - темы
Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Urticaria , Drug Therapy
10.
Статья в Китайский | WPRIM | ID: wpr-658338

Реферат

Objective To observe the clinical efficacy of Shugan Hewei Formula for cancer-related depression. Methods Totally 92 cancer-related depression patients were randomly divided into two groups, with 46 patients in each group. All patients already finished the treatment such as radiotherapy and chemotherapy, and were in stable stage. The Fluoxetine Hydrochloride Dispersible Tablets was given to the patients in the control group, 20 mg each time,once a day,orally;Shugan Hewei Formula was given to those in the treatment group,a dose a day,twice a day, orally. The treatment for both groups lasted for 6 weeks. Before and after treatment, HAMD scores and KPS scores were observed; the change of cerebral neurotransmitters levels in the brain of patients were detected; IL-6 and TNF-α in serum were tested by ELISA. Results HAMD scores in the two groups decreased markedly after treatment (P<0.05). HAMD scores in treatment group was less than that in control group after treatment (P<0.05). KPS scores increased in treatment group after treatment, and were better than the control group (P<0.05). The contents of NE, 5-HT increased, IL-6 and TNF-αdecreased in both groups after treatment (P<0.05). The contents of NE and 5-HT in the treatment group were higher than the control group after treatment, while the contents of IL-6 and TNF-α were lower than the control group (P<0.05, P<0.01). No adverse reactions and side effects were observed in the treatment group. 5 cases of mild nausea and 6 cases of abnormal liver function were found in the control group. Conclusion Shugan Hewei Formula can increase the contents of NE and 5-HT in the brain of cancer-related depression patients, decreased cytokines levels, and improve patients' depressive state.

11.
Статья в Китайский | WPRIM | ID: wpr-661257

Реферат

Objective To observe the clinical efficacy of Shugan Hewei Formula for cancer-related depression. Methods Totally 92 cancer-related depression patients were randomly divided into two groups, with 46 patients in each group. All patients already finished the treatment such as radiotherapy and chemotherapy, and were in stable stage. The Fluoxetine Hydrochloride Dispersible Tablets was given to the patients in the control group, 20 mg each time,once a day,orally;Shugan Hewei Formula was given to those in the treatment group,a dose a day,twice a day, orally. The treatment for both groups lasted for 6 weeks. Before and after treatment, HAMD scores and KPS scores were observed; the change of cerebral neurotransmitters levels in the brain of patients were detected; IL-6 and TNF-α in serum were tested by ELISA. Results HAMD scores in the two groups decreased markedly after treatment (P<0.05). HAMD scores in treatment group was less than that in control group after treatment (P<0.05). KPS scores increased in treatment group after treatment, and were better than the control group (P<0.05). The contents of NE, 5-HT increased, IL-6 and TNF-αdecreased in both groups after treatment (P<0.05). The contents of NE and 5-HT in the treatment group were higher than the control group after treatment, while the contents of IL-6 and TNF-α were lower than the control group (P<0.05, P<0.01). No adverse reactions and side effects were observed in the treatment group. 5 cases of mild nausea and 6 cases of abnormal liver function were found in the control group. Conclusion Shugan Hewei Formula can increase the contents of NE and 5-HT in the brain of cancer-related depression patients, decreased cytokines levels, and improve patients' depressive state.

12.
Статья в Китайский | WPRIM | ID: wpr-621032

Реферат

Electric field treatment of tumor technology is of great significance in the treatment of glioma,including direct current electric field and alternating electric field.Direct current electric field affects the migration of glioma cells,and can be used as a new clue for the treatment of glioma.While alternating electric field can inhibit the proliferation and invasion of glioma cells,and induce apoptosis,and can obviously prolong the survival period of patients with glioma and improve their quality of life.

13.
Journal of Preventive Medicine ; (12): 770-775, 2016.
Статья в Китайский | WPRIM | ID: wpr-792529

Реферат

Objective To evaluate the association of cervical cancer and the G/C single nucleotide polymorphism at codon 72 in p53 gene exon -4 in Chinese population.Methods Literatures were searched in CNKI,VIP,CBM, PubMed,EMBase,the Cochrane Library (Issue 1,2015),WanFang Data Database (1980—2015)with computer. Results Thirteen studies involving 1 780 cervical cancer patients and 1 5 17 healthy volunteers were included.According to the situation of the HPV infection in research object,thirteen studies were divided into two subgroups.The results of meta-analyses in the subgroup of non-HPV infection showed that the Chinese women having the genotype G/G presented no increased relative risk compared to that with the genotype C/C(OR=0.980,95%CI:0.558 -1.723).The allele G showed no increased relative risk compared to the allele C (OR=1.070,95%CI:0.789-1.449)The results of meta-analyses in the subgroup of HPV infection showed that the Chinese women having the genotype G/G presented no increased relative risk compared to that with the genotype C/C(OR=0.891,95%CI:0.213 -3.722).The allele G showed no increased relative risk compared to the allele C (OR =0.981,95%CI:0.493 -1.951 ).Conclusion This meta -analysis demonstrates that G/C single nucleotide polymorphism at codon 72 in p53 gene exon-4 were not associated with cervical cancer in Chinese women.

14.
Zhonghua nankexue ; Zhonghua nankexue;(12): 996-998, 2013.
Статья в Китайский | WPRIM | ID: wpr-268016

Реферат

<p><b>OBJECTIVE</b>To discuss the effect and safety of preventive administration of antibiotics to patients with benign prostatic hyperplasia (BPH) before urodynamic examination.</p><p><b>METHODS</b>A total of 256 BPH patients to undergo urodynamic examination were randomly divided into a control group (n = 118) and a trial group (n = 138). The former received no pre-treatment while the latter were given cefoxitin sodium iv at 1.0 g 30 minutes before complete urodynamic examination. Then we compared the incidence rates of urinary tract infection between the two groups.</p><p><b>RESULTS</b>Statistically significant differences were found in the incidence rate of urinary tract infection between the control and trial groups (20.3% [24/118] vs 7.3% [10/138], P < 0.01), as well as in those with diabetes mellitus (6.7% [3/45] vs 23.5% [8/34], P < 0.05), those with residual urine > 50 ml (5.4% [3/56] vs 18.5% [10/54], P < 0.05), and those with both diabetes mellitus and residual urine (9.5% [2/21] vs 44.4% [8/18], P < 0.05). Only 3 patients (2.2%) in the trial group had mild adverse drug reactions.</p><p><b>CONCLUSION</b>For BPH patients, particularly those with diabetes mellitus and residual urine, preventive administration of antibiotics before urodynamic examination is safe and can effectively protect the patients against urinary tract infection.</p>


Тема - темы
Humans , Male , Antibiotic Prophylaxis , Cefoxitin , Prostatic Hyperplasia , Diagnosis , Urinary Tract Infections , Urodynamics
15.
Статья в английский | WPRIM | ID: wpr-819663

Реферат

OBJECTIVE@#To evaluate the shear bond strength (SBS) between alumina-toughened zirconia (ATZ) cores and veneering ceramics, investigate the effect of aging in artificial saliva on SBS and compare it with that of yttria-stabilized tetragonal zirconia polycrystals(Y-TZP).@*METHODS@#Bars of ATZ and Y-TZP were layered with veneering ceramics in accordance to the recommendation of the manufacturer. Half of each group (n = 10) was aged at 134 °C (under 2 bar pressure) in an autoclave for 48 h. Subsequently, all specimens were subjected to shear force in a universal testing machine. The interface and fractured surface of the specimens were evaluated using scanning electron microscopy and X-ray energy dispersive spectroscopy.@*RESULTS@#The initial mean SBS values in MPa±SD were 28.9±8.0 for ATZ and 26.2±7.6 for Y-TZP. After aging, the mean SBS values for ATZ and Y-TZP were 22.9±4.9 MPa and 22.8±6.9 MPa, respectively. Neither the differences between the SBS values of the ATZ and Y-TZP groups nor the influence of aging on all groups were statistically significant.@*CONCLUSIONS@#The SBS between the ATZ core and the veneering ceramics was not affected by aging. The SBS of ATZ to veneering ceramics was not significantly different compared with that of Y-TZP.


Тема - темы
Aluminum Oxide , Reference Standards , Ceramics , Reference Standards , Dental Veneers , Reference Standards , Microscopy, Electron, Scanning , Prosthesis Failure , Saliva, Artificial , Pharmacology , Shear Strength , Spectrum Analysis , Yttrium , Reference Standards , Zirconium , Reference Standards
16.
Статья в Китайский | WPRIM | ID: wpr-235089

Реферат

<p><b>OBJECTIVE</b>The objective of this study is to investigate the influence of zirconia content which is 0-30.0% weight percentage of matrix on translucency of zirconia-toughened alumina glass-infiltrated ceramics.</p><p><b>METHODS</b>Seven groups were divided according to different weight percentage of zirconia (0, 2.5%, 5.0%, 7.5%, 10.0%, 20.0% and 30.0%). After sintering, infiltrating and polishing, spectral transmittance was determined with spectrophotometer under D65 standard source. Contrast ratio was also tested by whiteness colorimeter.</p><p><b>RESULTS</b>With mass fraction of zirconia increasing from 0 to 30.0%, spectral transmittance reduced from 0.406% to 0.058%, while contrast ratio value increased from 0.849 +/- 0.005 to 1.015 +/- 0.006. When zirconia content was 10.0%, contrast ratio was 0.990 +/- 0.008. When it was more than 10.0%, transmission rate of the downward trend and contrast ratio of the rising trend became flat.</p><p><b>CONCLUSION</b>Zirconia content has a direct impact on translucency of zirconia-toughened alumina glass-infiltrated ceramic, which is essentially opaque when zirconia content is 10.0%. When mass fraction of zirconia is more than 10.0%, the influence of zirconia content is reduced.</p>


Тема - темы
Aluminum Oxide , Ceramics , Dental Materials , Dental Porcelain , Glass , Zirconium
17.
Chinese Journal of Stomatology ; (12): 376-380, 2010.
Статья в Китайский | WPRIM | ID: wpr-243127

Реферат

<p><b>OBJECTIVE</b>To study the effects of alumina content on sintered density, mechanical property and translucency of zirconia nanocomposite all-ceramics.</p><p><b>METHODS</b>Specimens of zirconia nanocomposite all-ceramics were divided into five groups based on their alumina content which are 0% (control group), 2.5%, 5.0%, 7.5% and 10.0% respectively. The sintered densities were measured using Archimedes' method. Specimens' bending strengths were measured with three-point bending test (ISO 6872). The visible light transmittances were measured with spectrophotometric arrangements and the fractured surfaces were observed using scanning electron microscope (SEM).</p><p><b>RESULTS</b>The control group of pure zirconia could be sintered to the theoretical density under pressure-less sintering condition. The bending strength was (1100.27 ± 54.82) MPa, the fracture toughness was (4.96 ± 0.35) MPa×m(1/2) and the transmittance could reach 17.03%. The sintered density and transmittance decreased as alumina content increased from 2.5% to 10%. However, the fracture toughness only increased slightly. In all four alumina groups, the additions of alumina had no significant effect on samples' bending strengths (P > 0.05). When the content of alumina was 10%, fracture toughness of specimens reached (6.13 ± 0.44) MPa×m(1/2) while samples' transmittance declined to 6.21%. SEM results showed that alumina particles had no significant effect on the grain size and distribution of tetragonal zirconia polycrystals.</p><p><b>CONCLUSIONS</b>Additions of alumina to yttria-tetragonal zirconia polycrystals could influence its mechanical property and translucency. Additions of the other phase to zirconia ceramics should meet the clinical demands of strength and esthetics.</p>


Тема - темы
Aluminum Oxide , Chemistry , Ceramics , Chemistry , Dental Porcelain , Chemistry , Dental Stress Analysis , Elasticity , Hardness , Materials Testing , Microscopy, Electron, Scanning , Nanoparticles , Pliability , Surface Properties , Yttrium , Chemistry , Zirconium , Chemistry
18.
Chinese Journal of Stomatology ; (12): 439-443, 2010.
Статья в Китайский | WPRIM | ID: wpr-243155

Реферат

<p><b>OBJECTIVE</b>To prepare a novel apatite-wollastonite bioactive glass-ceramic-calcium sulphate hemihydrate(AW-BGC-CSH) composite, to study its biocompatibility, and to provide experimental support for its further clinical application.</p><p><b>METHODS</b>Samples of AW-BGC-CSH composite were prepared with different AW-BGC granules-CSH ratios (50%, 40%, 30%, 20%). Surface morphology, microstructure and mechanical features of the composite were measured. Osteoblasts were cultivated in vitro on the composite. Cell morphology, proliferation, and the alkaline phosphatase (ALP) activity of osteoblasts were examined to determine the biocompatibility of the composite.</p><p><b>RESULTS</b>The composite showed a three-dimensional pored structure with communicated micropores under scanning electron microscopy (SEM). The plasticity of the composite could be maintained within 3 - 5 min. Its top solidification temperature was 36.4°C and the maximum compressive strength was 9.3 MPa. The osteoblasts adhered to the composite and grew well. At 1, 3, 5, 7 d after cultivated, the microprotein contents of the composite were (251 ± 12), (296 ± 31), (580 ± 13) and (571 ± 15) mg/L, and the ALP activity of the composite were (4.50 ± 0.68), (6.90 ± 0.27), (12.05 ± 0.28) and (11.86 ± 0.63) U/mg. The results of the ALP activity and microprotein contents in the experiment group were significantly higher than those in the control group (P < 0.05).</p><p><b>CONCLUSIONS</b>The prepared AW-BGC-CSH composite has a three-dimensional pored structure, favourable plasticity, mechanical property and good biocompatibility.</p>


Тема - темы
Apatites , Chemistry , Biocompatible Materials , Chemistry , Calcium Compounds , Chemistry , Calcium Sulfate , Chemistry , Cells, Cultured , Ceramics , Chemistry , Materials Testing , Osteoblasts , Cell Biology , Silicates , Chemistry
19.
Статья в Китайский | WPRIM | ID: wpr-246614

Реферат

<p><b>OBJECTIVE</b>To evaluate the effect of different root canal irrigants on smear layer removal and dentinal tubule opening of root canal surfaces after post space preparation.</p><p><b>METHODS</b>Thirty maxillary anteriors were endodontically treated. After post space preparation, the teeth were assigned to three groups with ten teeth each: group A, B, C. 3% H2O2, 15% ethylenediamine tetraacetic acid(EDTA), 15% EDTA and 3% NaClO were used as irrigant of group A, B, C. After post space irrigation, eight teeth of each group were examined under scanning electron microscope (SEM) for smear layer removal and dentinal tubule opening. The left two specimens were restored with fiber posts and prepared for evaluation of resin tag formation.</p><p><b>RESULTS</b>The cleansing effectiveness of group A, B and C was respectively 3.89 +/- 0.36, 1.77 +/- 0.30, 1.25 +/- 0.21. The dentinal tubule opening of group A, B and C was respectively (2.53 +/- 0.19), (3 11 +/- 023) (3.83 +/- 0.52) microm. The cleansing effectiveness and dentinal tubule opening of root canal surfaces were significantly affected by different root canal irrigants (P < 0.05). Excessive erosion of the dentin was observed in group C. Resin tag formation differed between the three irrigant groups, and group B showed excellent resin tag formation.</p><p><b>CONCLUSION</b>Irrigation with 15% EDTA after post space preparation can excellently remove the smear layer and improve dentinal tubule opening, permitting well penetration of resin adhesive into the dentinal tubules and collagen fibrillar structure.</p>


Тема - темы
Humans , Dental Pulp Cavity , Dentin , Edetic Acid , Hydrogen Peroxide , Microscopy, Electron, Scanning , Root Canal Irrigants , Root Canal Preparation , Root Canal Therapy , Smear Layer , Sodium Hypochlorite , Tooth Root
20.
Статья в Китайский | WPRIM | ID: wpr-248316

Реферат

<p><b>OBJECTIVE</b>To investigate the effects of Sol-Gel coating on the corrosion resistance of nickel-chronium alloys in vitro.</p><p><b>METHODS</b>The bond strength of coating-substrate interface sintered at different temperatures (300, 400, 500, 600 degrees C) was tested by scratching method. The Sol-Gel coating was analyzed by scanning electron microscope (SEM), and its corrosion resistance was assessed by a static immersion method.</p><p><b>RESULTS</b>The bond strength of coating-substrate interface reaches the peak at 400 degrees C. The Sol -Gel coating can apparently inhibit the release of metal ions and improve the corrosion resistance of nickel-chromium alloy.</p><p><b>CONCLUSION</b>Sol-Gel coating can evidently improve corrosion resistance of the nickel-chromium alloy, which has great potential in prospective clinical practice.</p>


Тема - темы
Humans , Alloys , Chromium Alloys , Corrosion , Dental Alloys , Nickel , Polymethyl Methacrylate , Prospective Studies
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