Objective: To investigate the feasibility of parameter-optimized magnetic resonance imaging (MRI) as the first choice for imaging examination in patients with acute ischemic stroke (AIS), and to assess the effects of quality improvement (QI) measures on shortening the door-to-needle time (DNT). Methods: A retrospective case-control study was conducted. A total of 69 AIS patients hospitalized at the Department of Neurology of the People's Hospital of Wuzhou from August 2015 to July 2018 were enrolled in the study, and the head MRI was used as the first choice for imaging examination. All patients received the intravenous thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA). Patients with AIS undergoing intravenous thrombolysis from August 2015 to March 2017 were included in the control group, and those receiving intravenous thrombolysis after QI measures from April 2017 to July 2018 were included in the experimental group. QI included informing the stroke team in advance by emergency physicians, treatment process changing from serial procedure to the parallel one, optimization of MRI scanning parameters, and use of rapid test instruments. The MRI scanning time was compared between the two groups. The DNT of the two groups was compared, and paired-samples t test was used. The proportion of patients who underwent MRI scan and DNT<60 min was compared between the two groups, and the χ² test was used. Results: Compared with the control group, the proportion of patients undergoing MRI scan in the experimental group was increased (82% vs 58%, χ²=4.58, P=0.032); MRI scanning time was shortened (4 min 37 s vs 10 min 21 s); DNT (min) was shortened (59.32±10.19 vs 93.48±24.81, t=7.189, P<0.01); and the proportion of patients with DNT<60 min was significantly increased (68% vs 6%, χ²=27.190, P<0.01). Conclusion Parameter-optimized MRI as the first choice for imaging examination in AIS patients with the onset time <4.5 h was feasible, and the DNT was significantly shortened by QI measures.

Objective To investigate the prevalence and genotype of thalassemia in high-risk children with thalassemia in Wuzhou, and to provide a reference for formulating strategies for the prevention and treatment of thalassemia and for reducing the incidence of thalassemia. Methods Four deletions and 3 point mutations of alpha-thalassemia and 17 point mutations of beta-thalassemia were detected and analyzed by GAP-PCR and PCR combined with reverse dot blot hybridization in children at a high risk for thalassemia in Wuzhou from 2010 to 2018. Results There were 1,421 positive cases in the first screening, and 871 cases were confirmed through genotyping, with a positive rate of 61.29%, including4 deletion types and 14 mutation types. There were 452 cases (51.89%) of α-thalassemia, 337 cases (38.69%) of β-thalassemia and 82 cases (9.41%) of combination of α-thalassemia and β-thalassemia. The common genotypes of α-thalassemia in children in Wuzhou were: --SEA/αα, --SEA/-α3.7, -α3.7/αα, --SEA/αCS αCS, αWSα/αα, --SEA/-α4.2, -α4.2/αα, and αCSα/αα. CD41-42, CD17, -28 and CD71-72 were the most common heterozygotes, while CD41-42/-28, CD41-42/IVS-2-654, and CD41-42/ CD71-72 were the most common double heterozygotes in children with β-thalassemia in Wuzhou. The most common homozygous genotypes were CD41-42 / CD41-42 and -28/-28. Conclusion In order to control thalassemia it is critical to increase investment in large-scale screening of carriers of the thalassemia mutant gene, and to prevent the birth of children with severe thalassemia.

Objective : To compare the accuracies of implants with dynamic real-time navigation versus digital guide navigation to provide a reference for clinical precision dental implants. Methods: Forty-six cases (seventy teeth) with missing teeth admitted to the Department of Stomatology, Wuzhou Red Cross Hospital from April 2018 to December 2019 were randomly divided into two groups (thirty-five teeth in each group) for dynamic real-time navigation and digital guide navigation implantation techniques. To compare the entry point, apex point, depth and angle deviation of the preoperative and postoperative position of implants in the two groups. SPSS 21.0 software was used for statistical analysis. Results : Dental implants were successfully placed in both groups. The deviations of apex point, depth and angle in the dynamic real-time navigation group were all smaller than those in the digital guide navigation group, and the differences were statistically significant (P < 0.05). There was no statistically significant deviation in the entry point between the two groups (P > 0.05). Conclusion In this study, both techniques had good clinical effects. The accuracy of dynamic real-time navigation was higher than that of digital guidance.

This study was aimed to investigate the prevalence and genotype distribution of heterozygotes in beta-thalassemia combining deletional alpha-thalassemia by using molecular detection and haematological methods. Three common deletions of alpha-thalassemia were detected by using gap-PCR. The mutations of beta-thalassemia were identified by using PCR with reverse dot blot hybridization. The routine analysis of blood cells was carried out. The results indicated that 15 cases from the 81 beta-thalassemia traits were found to be the compound heterozygosity for beta-thalassemia and alpha-thalassemia with 9 different types of gene defects with 18.52% detection rate. There were 6 cases (7.41%) of beta-thalassemia heterozygote combining alpha-thalassemia-1 gene (--(SEA)/alphaalpha), 8 cases (9.88%) combining with alpha-thalassemia-2 gene including 6 (7.41%) right ward deletion (-alpha(3.7)/alphaalpha) and 2 (2.47%) left ward deletion (-alpha(4.2)/alphaalpha), and 1 case (1.23%) combining deletional HbH gene (--(SEA)/-alpha(3.7)). No significant differences were found between beta-thalassemia heterozygotes combining deletional alpha-thalassemia and pure beta-thalassemia in all RBC parameters. It is concluded that the incidence of beta-thalassemia heterozygotes combining with deletional alpha-thalassemia is frequent in Wuzhou city. The hematological analysis can not give specificity for diagnosing these dual heterozygotes. Gap-PCR as a routine method for thalassemia screening has the advantages in reducing the possibility of failing to detect the combining heterozygosity for beta-thalassemia and alpha-thalassemia. It is more useful for genetic counselling and prenatal diagnosis of this disease.
Adolescent ; Adult ; Female ; Gene Deletion ; Genetic Carrier Screening ; methods ; Genotype ; Heterozygote ; Humans ; Male ; alpha-Thalassemia ; genetics ; beta-Thalassemia ; genetics

OBJECTIVETo investigate the influences of varying lingual traction forces on the space-closing speed in a typodont model.

METHODSForty-two Angle Class I standard typodont models of bimaxillary teeth protrusion were divided into 7 equal groups. Four regions of the model were paired to groups, and in the odd-numbered models, the top left and bottom left regions served as the experimental group and the top right and bottom right regions as the control group; in the even-numbered models, the regions in the model were grouped oppositely. In the experimental group, the space was closed by niti wire extension spring in the buccal ridge combined with lingual elastic traction of 0, 5, 10, 15, 20, 25 and 30 g. In the control group, the space was closed by exclusive niti wire extension spring in the buccal ridge. The space-closing speed were analyzed in all the groups.

RESULTSThe space-closing speed was significantly lower in the control group than in the experimental groups with lingual traction forces of 5, 10, 15, 20 and 25 g (P<0.05), but a traction force of 30 g resulted in a significantly lower speed than that in the control group (P<0.05). The space closing speed was the greatest in the experimental group with a traction force of 15 g (P<0.05).

CONCLUSIONNiti wire extension spring in the buccal ridge combined with lingual elastic traction results in faster space-closing speed than traditional exclusive niti wire extension spring. The speed is the fastest by applying 15 g lingual traction, which is also associated with the lowest slip resistance.

Dental Models ; Dental Stress Analysis ; Tooth Extraction ; methods ; Traction

Objective To investigate the effect of taking medical students as standardized patients(SSP) on problem based leaming(PBL) teaching in clerkship.Methods Totally 161 students (grade 2008) selected from clinical medical department was divided into PBL group(n=81) and lecture-based learning(LBL) group(n=80).SSP was introduced into PBL teaching and LBL group was taught by LBL.After the clerkship,theory test was conducted in two groups and questionnaire was given to LBL group.Statistical analyses were conducted by SPSS 13.0,measurement data were analyzed by t test and enumeration data were described by frequency and constituent ratio.Results Theory test results showed that the average score of medical record analysis was (37.35 ± 5.95) in PBL group,much higher than (33.25 ± 4.89) in LBL group(P=0.001) ;the total score was (71.20 ± 8.67) in PBL group,much higher than that of (67.79 ± 9.87) in LBL group(P=0.018) as well.The average scores of choice question in 2 groups were (33.85 ± 5.05) and (34.24 ± 6.87),without significant differences(P=0.658).The constituent ratio of answer ‘OK' regarding 10 entries in questionnaire was more than 75％.The constituent ratio of answer ‘OK' regarding 3 entries(SSP matching degree,SSP without implied language or action,stimulating the learning interest) was more than 90％.Conclusions Introducing SSP PBL teaching can improve students' ability of clinical analysis and problem solving but not so effective for the basic theoretical knowledge grasp.SSP could replace standardized patients in PBL teaching.

The breast cancer is a usual and serious malignant tumor which threatens the women′s health.Molecular subtyping bases on the molecular level, and provides a new classification method for the breast cancer pathology classification, and plays an important guidance significance for the clinical treatment.At present, the breast cancer molecular subtyping is mainly divided into the following subtypes: the Luminal A type and Luminal B type, HER-2 overexpression and the triple negative breast cancer.Different molecular subtyping has different characteristics in treatment reaction, prognosis and the clinical application situation.

Objective:A new algorithm based on Hough transform (HT) was proposed to improve the accuracy and stability of the film image analysis of Automatic Quality Assurance (AQA) test, and to explore the influence of the resolution of film image on the test results.Methods:Nine pairs of films were obtained for AQA modules in this study. Firstly, the median filter was used to preprocess the grayed-out film image to remove noise interference. Then, a global threshold was utilized to binarize the image. The images were edge-detected and the film edge line was extracted by Hough transform. The film image was transformed to the correct position. Finally, the edge of the field shadow circle and the shadow circle of the tungsten ball were extracted by the edge detection method and Hough transform. The radial error was finally obtained by analyzing the concentricity.Results:There was no significant difference in the accuracy between the test results yielded by the HT method and the AQA software ( P>0.05). The difference in the standard deviation of the test results was statistically significant ( P=0.027), indicating that the algorithm increased the stability while ensuring the accuracy of film analysis. Increasing the resolution of film scanning failed to significantly improve the accuracy and stability of film analysis in both two methods. Conclusions:The algorithm used in this study can eliminate the human error caused by film scanning placement while ensuring the accuracy of film analysis, providing a more stable way for the AQA test of the CyberKnife system.

Objective To observe the therapeutic effect on the treatment of avascular necrosis of femoral head by core decompression with autograft of mesenchymal stem cells(MSCs).Methods Nineteen patients with avascular necrosis of femoral head,including 8 cases of phase I,6 cases of phase II and 5 cases of phase III based on ARCO classification,were treated with core decompression with autograft of MSCs.Results The patients were followed up for one year.The average ratio of necrosis zone diminished from 31.88% to 13.18%.The Harris hip score was increased significantly.Conclusion The treatment of core decompression with autograft of MSCs is safe and effective,and it deserves to application in early necrosis of femoral head.

OBJECTIVEThis study was aimed to investigate the diagnostic value of combined determination of Epstein-Barr virus (EBV) antibodies for nasopharyngeal carcinoma (NPC), including immunoglobulin (Ig) A against EBV capsid antigens (VCA), IgA against early antigens (EA), IgG against BRLF1 transcription activator (Rta) and IgA against EBV nuclear antigen-1 (EBNA1), assessed with receiver operating characteristic (ROC) curve based on logistic regression.

METHODSSerum samples derived from 211 untreated patients with NPC and 203 non-NPC ENT patients were examined for the presence of VCA/IgA and EA/IgA by immunoenzymatic assay, Rta/IgG and EBNA1/IgA by enzyme-linked immnunosorbent assay (ELISA). The different Logistic regression models were established for various combined determinations of antibodies, respectively. Using the predicted probability as the analyzed variable, ROC curve was applied to evaluate the diagnostic accuracy of different combined determinations.

RESULTSThe sensitivity of VCA/IgA (98.1%) and the specificity of EA/IgA (98.5%) were the highest while detecting solely. The results which were analyzed by ROC curve based on Logistic regression showed that the sensitivity and specificity were improved. In two-marker combinations, VCA/IgA + Rta/IgG whose area under ROC curve (AUC) was 0.991 had the highest diagnostic accuracy, and its sensitivity, specificity and Youden index were 94.8%, 98.0% and 0.928 respectively. No significant difference of AUC were found comparing VCA/IgA + Rta/IgG with VCA/IgA + Rta/IgG + EBNA1/IgA and four-marker combination( P > 0.05), of which sensitivity, specificity and Youden index were 94.8%, 98.5%, 0.933 and 96.7%, 97.0%, 0.937, respectively.

CONCLUSIONThe approach of ROC curve based on Logistic regression can improve synthetic efficiency for combined determination of multiple markers. The combined determination of VCA/IgA and Rta/IgG with a complementary effect is optimal for NPC serodiagnosis.

Adult ; Aged ; Aged, 80 and over ; Antibodies, Viral ; blood ; immunology ; Carcinoma ; diagnosis ; immunology ; virology ; Enzyme-Linked Immunosorbent Assay ; methods ; standards ; Female ; Herpesvirus 4, Human ; immunology ; Humans ; Logistic Models ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; diagnosis ; immunology ; virology ; Viral Proteins ; immunology ; Young Adult