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find Author "YANG Guang" 20 results
  • Influence of the concrete and abstract graphs on N200 and P300 potentials

    Increasing the amplitude of event-related potential is one of the key methods to improve the accuracy of the potential-based brain-computer interface, e.g., P300-based brain-computer interface. The brain-computer interface systems often use symbols or controlled objects as vision stimuli, but what visual stimuli can induce more obvious event-related potential is still unknown. This paper designed three kinds of visual stimuli, i.e., a square, an arrow, and a robot attached with an arrow, to analyze the influence of concreteness degree of the graph on the N200 and P300 potentials, and applied a support vector machine to compare the performance of the brain-computer interface under different stimuli. The results showed that, compared with the square, the robot attached with arrow and the arrow both induced larger N200 potential (P = 1.6 × 10−3, P = 4.2 × 10−2) and longer P300 potential (P = 2.2 × 10−3, P = 1.9 × 10−2) in the frontal area, but the amplitude under the arrow condition is smaller than the one under the robot attached with arrow condition. The robot attached with arrow increased the N200 potential amplitude of the square and arrow from 3.12 μV and 5.19 μV to 7.21 μV (P = 1.6 × 10−3, P = 8.9 × 10−2), and improved the accuracy rate from 59.95%, 61.67% to 74.45% (P = 2.1 × 10−2, P = 1.6 × 10−2), and the information transfer rate from 35.00 bits/min, 35.98 bits/min to 56.71 bits/min (P = 2.6 × 10−2, P = 1.6 × 10−2). This study shows that the concreteness of graphics could affect the N200 potential and the P300 potential. The abstract symbol could represent the meaning and evoke potentials, but the information contained in the concrete robot attached with an arrow is more correlated with the human experience, which is helpful to improve the amplitude. The results may provide new sight in modifying the stimulus interface of the brain-computer interface.

    Release date:2020-08-21 07:07 Export PDF Favorites Scan
  • Experimental Study on Excluded Esophagus after Tracheoesophageal Fistula Was Treated with Esophageal Exclusion Surgery YANG Guang, BAI Guang

    Abstract: Objective To investigate the change of tissue structure and epithelial barrier function of excluded esophagus after esophageal exclusion surgery for tracheoesophageal fistula (TEF). Methods Twentyeight hybrid dogs were divided into 3 groups with random number method. For group A (n=12), fistula was excluded; for group B (n=12), only the esophagus was excluded; and group C (n=4) was the control group. The normal and excluded esophagus of the three groups were observed through general sampling, HE staining, transmission electron microscope (TEM), scanning electron microscope (SEM) and Lanthanum trace labeling. The interstitial space dilation (ISD) of the cells on the esophageal mucosa was measured and the number of desmosome in the intercellular space was calculated. Results The changes of tissue structure and epithelial barrier function of the excluded esophagus were similar between group A and group B. Compared with group C, group A and B showed the following changes: esophageal structure changed, submucous glandular tissues reduced or disappeared; the interstitial space increased, the number of desmosome decreased, and the epithelial barrier function attenuated, but the basal lamina did not changed and lanthanum did not break through it. For the dogs in group C, esophageal mucosa could be observed, submucosa was complete and a large number of gland tissues and micrangiums could be seen in it. The number of desmosome for group A, B and C was 0.21±0.03 entries/μm2, 0.22±0.05 entries/μm2, and 0.32±0.03 entries/μm2 respectively, which showed a significant difference between group A, B and group C (Plt;0.05), while there was no significant difference between group A and group B (Plt;0.05). The average interstitial space for group A, B and C was 2.11±0.56 μm, 2.04±0.77 μm, and 1.84±0.49 μm respectively. There was no significant difference between group A and B, while there was significant difference between group A, B and group C. Conclusion The esophageal exclusion surgery for refractory TEF is safe, feasible, and effective with few complications, and deserved to be popularized.

    Release date:2016-08-30 06:03 Export PDF Favorites Scan
  • Clinical Study on Varicella Treated with IFN-α

    目的:探讨干扰素治疗水痘的效果。方法:将151例水痘患者随机分为3组, 治疗组Ⅰ给予干扰素100 万U/ 次,im,隔日1 次,连用3 次,治疗组Ⅱ同时予以干扰素局部外涂于水痘处, 2 次/ d;对照组病毒唑10 mg/ (kg·d),im, 一日2 次,连用5 天。除以上治疗外,3组均同时根据病情给予退热、止痒、抗炎等对症治疗。观察3组患者症状、体征变化。结果:治疗组患者症状、体征恢复所用时间明显优于对照组,同时还发现局部外涂干扰素于水痘处,其皮疹瘙痒、结痂恢复天数明显缩短。结论:干扰素治疗水痘可减轻症状,缩短病程,配合局部外用效果更佳。

    Release date:2016-09-08 09:56 Export PDF Favorites Scan
  • Research progress of producing genetically modified pigs by CRISPR/Cas9 in the medical field

    As pigs are similar to humans in anatomy, physiology and pathology, nutrition metabolism and disease characteristics, genetically modified pigs are already used for the studies of disease mechanism, pathology and toxicology and the evaluation of drugs. But the production of large modified animals is difficult, cumbersome, time-consuming and costly. With the breakthrough of gene editing technology, clustered regularly interspersed short palindromic repeat (CRISPR)/CRISPR-associated 9( Cas9)(CRISPR/Cas9) technology has greatly improved the mutation efficiency, reduced the cost and simplified the steps, and promoted the widespread application of genetically modified pigs. In this paper, the production methods of genetically modified pigs and the research progress of genetically modified pigs by CRISPR/Cas9 in the medical field were reviewed.

    Release date:2018-08-23 05:06 Export PDF Favorites Scan
  • Anterior mediastinal inflammatory myofibroblastic tumor with thymoma: A case report

    Anterior mediastinal inflammatory myofibroblastoma is a rare tumor with insidious onset and easy misdiagnosis. In this report, we presented a case of anterior mediastinal inflammatory myofibroblastoma with thymoma. The mediastinal tumor was found by physical examination, and the prognosis was good after surgical treatment. For this disease, operation is an effective method for definite diagnosis and treatment, and complete excision can achieve good outcomes.

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  • Clinical effect of anal fistula clip in treatment of anal fistula

    ObjectiveTo analyze the effect of anal fistula clip (AFC) in the treatment of anal fistula, and to evaluate its safety. MethodsA historical cohort study method was conducted. Eighty-three patients with glandular transsphincteric anal fistula in the Xuzhou Central Hospital from September 2018 to May 2021 were collected, of which 42 patients underwent the AFC treatment (AFC group), 41 patients underwent the endorectal advancement flap (ERAF) treatment (ERAF group). The operation time, intraoperative blood loss, visual analogue scale (VAS) score of anus pain on postoperative day 1, 3, and 7, wound healing time, Wexner incontinence score of anal function on postoperative month 6, and clinical efficacy (healing and failure) were compared between the two groups. ResultsThe operation was successfully completed in both groups. The operation time and intraoperative blood loss in the AFC group were shorter or less than those in the ERAF group (P<0.05). No complications such as internal opening infection and bleeding occurred in the two groups. There were no statistical differences in the VAS score of postoperative anus pain at all time point between the two groups (P>0.05). The median follow-up time was 22 months. There was no statistical difference in the wound healing time between the two groups (P>0.05). The Wexner score of anal function in the AFC group was lower than that in the ERAF group (P<0.05), and there was no statistical difference between after operation and before operation (Z=–1.751, P=0.089) in the AFC group, while that in the ERAF group after operation was higher than before operation (Z=–1.859, P=0.014). The healing rate had no statistical difference between the AFC group and ERAF group (85.7% versus 77.5%, χ2=0.925, P=0.336). Conclusion From the results of this study, the AFC is safe and effective in treatment of anal fistula, with the advantages of relatively simple operation, less bleeding during operation, lighter postoperative pain, and good protection of anal function.

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  • Application of generative adversarial network in magnetic resonance image reconstruction

    Magnetic resonance imaging (MRI) is an important medical imaging method, whose major limitation is its long scan time due to the imaging mechanism, increasing patients’ cost and waiting time for the examination. Currently, parallel imaging (PI) and compress sensing (CS) together with other reconstruction technologies have been proposed to accelerate image acquisition. However, the image quality of PI and CS depends on the image reconstruction algorithms, which is far from satisfying in respect to both the image quality and the reconstruction speed. In recent years, image reconstruction based on generative adversarial network (GAN) has become a research hotspot in the field of magnetic resonance imaging because of its excellent performance. In this review, we summarized the recent development of application of GAN in MRI reconstruction in both single- and multi-modality acceleration, hoping to provide a useful reference for interested researchers. In addition, we analyzed the characteristics and limitations of existing technologies and forecasted some development trends in this field.

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  • Methods of animal experiment ethics training at home and abroad: an evidence-based analysis and summary

    Objective To summarize the methods and experience of animal experiment ethics training at home and abroad, analyze the opportunities and problems, and explore the ethics training methods suitable for the current situation of animal experiments in China. Methods Documents relating to animal experiment ethics training from January 2012 to February 2022 were searched in PubMed, Embase, China National Knowledge Infrastructure and Wanfang Data databases. After literature screening and data extraction by 2 researchers independently, descriptive analysis was performed. Results A total of 44 documents were selected, including 19 in Chinese and 25 in English, involving 44 institutions. According to the literature analysis, in the United States, Britain and other developed countries, the welfare and ethical laws for laboratory animals were relatively perfect, such as the Animal Welfare Act of the United States, the Animals (Scientific Procedures) Act of Britain, the Animal Welfare Act of German, and the Act on Welfare and Management of Animals of Japan, while in China administrative regulations were the main ones, and most of the institutions were restricted by management regulations; the ethics of personnel involved in animal experiments were uneven; the training time of some domestic institutions was less than that of institutions abroad; domestic training methods and contents needed to be improved. Basing on the comparative results at home and abroad and combining the training experience, West China Hospital of Sichuan University improved the animal experiment ethics training system. Conclusion It is suggested that the animal experimental institutions in China should improve the training methods, to enhance the awareness and cognition of people involved in animal experiments more systematically and scientifically, and strengthen the ethical review.

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  • The Best Threshold Value of Hemoglobin A2 for Diagnosis of β-Thalassemia Carriers by High Performance Liquid Chromatography

    Objective To determine the best threshold value of hemoglobin A2 (HbA2) for diagnosis of β-thalassemia (β-thal) carriers by using high performance liquid chromatography (HPLC), and to improve the application value of HbA2 as a diagnostic index for β-thal carriers to reduce the rates of missed diagnosis and misdiagnosis. Methods Using reverse dot blot (RDB) as a gold standard method, HbA2 results of 1 007 β-thal carriers and 606 normal controls in the past two years determined by HPLC were divided into true positive, false positive, true negative, and false negative based on the different threshold values of HbA2 results. Then, the evaluation indexes such as sensitivity, specificity, positive and negative likelihood ratio, and Youden’s index were evaluated. Next, the receiver operator characteristic (ROC) curve was drawn to determine the best threshold value of HbA2 for diagnosis of β-thal carriers by HPLC. Results If ≥4.0% was taken as the threshold value of HbA2 for diagnosis of β-thal carriers by HPLC, the evaluation indexes values were shown as follows: sensitivity 99.21%, specificity 99.34%, positive likelihood ratio 150.30, negative likelihood ratio 0.008, and Youden’s index 0.99. The Youden’s index was better than the other threshold values, and the corresponding tangent point was the peak point of the ROC curve. Conclusion When ≥4.0% serves as the best threshold value of HbA2 for diagnosis of β-thal carriers using HPLC, integrated evaluation performance of the corresponding sensitivity and specificity is the most ideal, and the authenticity of the diagnostic test is the best.

    Release date:2016-09-07 02:10 Export PDF Favorites Scan
  • Comparison of the Effect of Ropivacaine Intraarticular Injection and Femoral Nerve Block for Analgesia after Knee Arthroscopy

    【摘要】 目的 比较单次股神经阻滞和关节腔内单次注射罗哌卡因对膝关节镜检术后镇痛效果,为临床应用提供试验依据。 方法 2009年1月-2010年7月,选择美国麻醉医师协会(ASA)Ⅰ~Ⅱ级、年龄18~65岁、拟行择期单侧下肢膝关节镜手术患者180例,随机分为股神经阻滞组和关节腔内用药组,每组90例,分别于术前1 h行股神经阻滞(0.15%罗哌卡因20 mL)和手术结束时在膝关节腔内注入0.6%罗哌卡因20 mL。于术后4、8、24 h采用视觉模拟评分法(visual analog scale,VAS)行静止和运动时疼痛评分,记录术后患者满意度、不良反应发生率,术后使用镇痛药物情况。 结果 关节腔内用药组术后镇痛药物使用率(41.11%)明显高于股神经阻滞组(20.00%)(Plt;0.005)。两组患者术后24 h静止时及术后8、24 h运动时的VAS评分关节腔内用药组均明显高于股神经阻滞组(Plt;0.001),其余各时点差异无统计学意义(Pgt;0.05)。 结论 股神经阻滞可提供更加有效的术后镇痛效果,并且用药量小,安全系数高,值得临床推广。【Abstract】 Objective To compare the effect of single-injection femoral nerve block and local anesthetic intraarticular injection for analgesia after knee arthroscopy, in order to provide the experimental base for clinical application. Methods From January 2009 to July 2010, 180 American Society of Anesthesiologists (ASA) physical status I-II patients, aged from 18 to 65 years old, and scheduled for elective single knee arthroscopy were randomly divided into two groups: femoral nerve block group and local anesthetic intraarticular injection group with 90 patients in each group. For the patients in the former group, 20 mL of 0.15% ropivacaine was injected 1 hour before operation. For the latter group, 20 mL of 0.6% ropivacaine was injected into the articular cavity after operation. Pain intension scores at rest and in motion were measured 4, 8, and 24 hours after operation by visual analog scale (VAS). The degree of patients’ satisfaction, adverse reaction incidence rate and information of taking pain-killers were also recorded. Results The rate of using pain-killers in the intraarticular injection group (41.11%) was dramatically higher than the femoral nerve block group (20.00%) (Plt;0.005). The VAS scores of patients in the intraarticular injection group at rest 24 hours after operation and in motion 8 hours and 24 hours after operation were significantly higher than the femoral nerve block group (Plt;0.001), while there was no significant difference at other points between the two groups. Conclusions Femoral nerve block is more efficient for analgesia after knee arthroscopy compared with local anesthetic intraarticular injection. It is a safe procedure requiring only a relatively small dose of medicine, and is worth being popularized.

    Release date:2016-09-08 09:24 Export PDF Favorites Scan
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