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Comparison of modified gunsight suture technique and traditional interrupted suture in enterostomy closure
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作者 Chang Chen Xiang Zhang +5 位作者 Zhi-Qiang Cheng Bin-Bin Zhang Xin Li Ke-Xin Wang yong dai Yan-Lei Wang 《World Journal of Gastroenterology》 SCIE CAS 2023年第29期4571-4579,共9页
BACKGROUND Prophylactic enterostomy surgery is a common surgical approach used to reduce the risk of anastomotic leakage in patients who have undergone partial intestinal resection due to trauma or tumors.However,the ... BACKGROUND Prophylactic enterostomy surgery is a common surgical approach used to reduce the risk of anastomotic leakage in patients who have undergone partial intestinal resection due to trauma or tumors.However,the traditional interrupted suturing technique used in enterostomy closure surgery has several issues,including longer surgical incisions and higher incision tension,which can increase the risk of postoperative complications.To address these issues,scholars have proposed the use of a“gunsight suture”technique.This technique involves using a gunsight incision instead of a traditional linear incision,leaving a gap in the center for the drainage of blood and fluid to reduce the risk of infection.Building on this technique,we propose an improved gunsight suture technique.A drainage tube is placed at the lowest point of the incision and close the gap in the center of the gunsight suture,which theoretically facilitates early postoperative mobility and reduces the burden of dressing changes,thereby reducing the risk of postoperative complications.AIM To compare the effectiveness of improved gunsight suture technique with traditional interrupted suture in closing intestinal stomas.METHODS In this study,a retrospective,single-center case analysis was conducted on 270 patients who underwent prophylactic ileostomy closure surgery at the Department of Colorectal Surgery of Qilu Hospital from April 2017 to December 2021.The patients were divided into two groups:135 patients received sutures using the improved gunsight method,while the remaining 135 patients were sutured with the traditional interrupted suture method.We collected data on a variety of parameters,such as operation time,postoperative pain score,body temperature,length of hospital stays,laboratory indicators,incidence of incisional complications,number of wound dressing changes,and hospitalization costs.Non-parametric tests and chi-square tests were utilized for data analysis.RESULTS There were no statistically significant differences in general patient information between the two groups,including the interval between the first surgery and the stoma closure[132(105,184)d vs 134(109,181)d,P=0.63],gender ratio(0.64 vs 0.69,P=0.44),age[62(52,68)years vs 60(52,68)years,P=0.33],preoperative body mass index(BMI)[23.83(21.60,25.95)kg/m²vs 23.12(20.94,25.06)kg/m²,P=0.17].The incidence of incision infection in the improved gunsight suture group tended to be lower than that in the traditional interrupted suture group[(n=2/135,1.4%)vs(n=10/135,7.4%),P<0.05],and the postoperative hospital stay in the improved gunsight suture group was significantly shorter than that in the traditional interrupted suture group[5(4,7)d vs 7(6,8)d,P<0.05].Additionally,the surgical cost in the modified gunsight suture group was slightly lower than that in the traditional suture group[4840(4330,5138)yuan vs 4980(4726,5221)yuan,P>0.05],but there was no significant difference in the total hospitalization cost between the two groups.CONCLUSION In stoma closure surgery,the improved gunsight technique can reduce the incision infection rate,shorten the postoperative hospital stay,reduce wound tension,and provide better wound cosmetic effects compared to traditional interrupted suture. 展开更多
关键词 ENTEROSTOMY Abdominal wound closure technique Suture techniques Surgical wound infection Hospital costs Hospital stay
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居家脊柱专项运动在胸椎后凸老年人中应用的可行性研究
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作者 李维颖 陆金玲 +2 位作者 代勇 羅鳯儀 周珮馨 《International Journal of Nursing Sciences》 CSCD 2023年第2期133-141,I0001,共10页
目的 评估不同运动习惯的中国老年人进行居家脊柱后凸专项运动的可行性,探讨该运动计划对减少胸椎后凸角度和改善活动能力的效果.方法 本研究采用单组前后对照研究设计.在中国武汉市4个社区选取20名年龄≥60岁,患有胸椎过度后凸畸形且... 目的 评估不同运动习惯的中国老年人进行居家脊柱后凸专项运动的可行性,探讨该运动计划对减少胸椎后凸角度和改善活动能力的效果.方法 本研究采用单组前后对照研究设计.在中国武汉市4个社区选取20名年龄≥60岁,患有胸椎过度后凸畸形且有康复潜力的老年人为研究对象.老年人接受为期6周的居家脊柱后凸专项运动干预,包括热身、肌肉加强、脊柱直立、脊柱灵活性和放松5个部分(22个动作),共有7次1 h的小组课程和35次的居家练习.在干预前后对老年人两种站立姿势下胸椎后凸角度、静态平衡、动态平衡、心肺功能、功能步态、疼痛及自我形象等指标进行评估并比较.采用老年人小组课程的出勤率、居家练习依从性及参与评价等指标来分析干预的可行性.结果 所有老年人均完成了小组课程和>75%的居家练习内容.干预后老年人在放松和最佳站立姿势下胸椎后凸角度较干预前均减少,中位数及四分位数间距分别 为-12.0°(-15.5°,-4.0°)(Z=-3.98,P<0.001)和-10.0°(-14.0°,-5.3°)(Z=-3.79,P<0.001).此外,干预后老年人疼痛程度明显减轻(P<0.001),自我形象认知得分提高(P<0.001),5项活动能力水平也有所提高(P<0.01).干预前后凸严重程度和日常体力活动强度不影响干预效果.大多数老年人认为干预强度适中且令人满意.结论 居家脊柱后凸专项运动在老年人胸椎过度后凸干预中具有可行性,并且可减少胸椎后凸角度,提升活动能力. 展开更多
关键词 老年 运动疗法 身体机能表现 体态 胸椎
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应用3D成像技术进行耻骨肌孔大小及角度的测量 被引量:4
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作者 耿兴隆 戴勇 +3 位作者 赵亮 秦伟 党宝宝 韩云 《中国内镜杂志》 2019年第9期48-52,共5页
目的利用3D成像技术进行人体耻骨肌孔的长度、耻骨肌孔的上区宽度、下区宽度、总宽度以及耻骨肌孔上下区域所成角度的测量。方法对该院2018年1月-2018年4月105例腹股沟疝患者进行术前薄层CT扫描,扫描后导出DICOM文件,并利用Mimics Resea... 目的利用3D成像技术进行人体耻骨肌孔的长度、耻骨肌孔的上区宽度、下区宽度、总宽度以及耻骨肌孔上下区域所成角度的测量。方法对该院2018年1月-2018年4月105例腹股沟疝患者进行术前薄层CT扫描,扫描后导出DICOM文件,并利用Mimics Research 19.0软件进行后期3D成像,建立盆腔3D模型,最后进一步精确测量耻骨肌孔的大小,包括耻骨肌孔的长度、上区域宽度、下区域宽度、总宽度以及上下区域所成角度。结果耻骨肌孔的长度为(7.4±0.3)cm,耻骨肌孔上区域宽度为(5.3±0.4)cm,耻骨肌孔下区域宽度为(2.7±0.2)cm,耻骨肌孔的总宽度为(7.9±0.4)cm,耻骨肌孔上下区域所成角度为(123.1±3.7)°,内镜下补片放置成功率100%,半年内复发率为0%。结论腹股沟疝用折叠型补片修补耻骨肌孔是相对适宜的,上片覆盖不小于7.4 cm(长)×5.3 cm(高)的三角扇形区域,下片覆盖不小于7.4 cm(长)×2.7(高)cm的三角扇形区域,上下区域所成角度约123.1°,该研究数据能够更精确地测量耻骨肌孔尺寸,为内镜下腹股沟疝腹膜前间隙修补手术提供理论数据基础,为补片设计及裁剪提供数据支持,也为微创内镜以后个体化治疗方案进行铺垫。 展开更多
关键词 腹股沟疝 3D成像技术 耻骨肌孔 内镜 测量
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1~H NMR-based serum metabolic profiling in compensatedand decompensated cirrhosis 被引量:10
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作者 Su-Wen Qi Zhi-Guang Tu +4 位作者 Wu-Jian Peng Lin-Xian Wang Xin Ou-Yang An-Ji Cai yong dai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第3期285-290,共6页
AIM: To study the metabolic profiling of serum samples from compensated and decompensated cirrhosis patients. METHODS: A pilot metabolic profiling study was conducted using three groups: compensated cirrhosis patients... AIM: To study the metabolic profiling of serum samples from compensated and decompensated cirrhosis patients. METHODS: A pilot metabolic profiling study was conducted using three groups: compensated cirrhosis patients (n = 30), decompensated cirrhosis patients (n = 30) and healthy controls (n = 30). A 1H nuclear magnetic resonance (NMR)-based metabonomics approach was used to obtain the serum metabolic profiles of the samples. The acquired data were processed by multivariate principal component analysis and orthogonal partial least-squares discriminant analysis (OPLS-DA). RESULTS: The OPLS-DA model was capable of distinguishing between decompensated and compensated cirrhosis patients, with an R2Y of 0.784 and a Q2Y of 0.598. Twelve metabolites, such as pyruvate, phenylala-nine and succinate, were identified as the most influential factors for the difference between the two groups. The validation of the diagnosis prediction showed that the accuracy of the OPLS-DA model was 85% (17/20). CONCLUSION: 1H NMR spectra combined with pattern recognition analysis techniques offer a new way to diagnose compensated and decompensated cirrhosis in the future. 展开更多
关键词 代谢分析 血清样品 核磁共振 肝硬化 NMR谱 偏最小二乘 主成分分析 代谢组学
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Application of modified primary closure of the pelvic floor in laparoscopic extralevator abdominal perineal excision for low rectal cancer 被引量:7
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作者 Yan-Lei Wang Xiang Zhang +6 位作者 Jia-Jia Mao Wen-Qiang Zhang Hao Dong Fan-Pei Zhang Shuo-Hui Dong Wen-Jie Zhang yong dai 《World Journal of Gastroenterology》 SCIE CAS 2018年第30期3440-3447,共8页
AIM To introduce a novel,modified primary closure technique of laparoscopic extralevator abdominal perineal excision(LELAPE) for low rectal cancer.METHODS We retrospectively analyzed data from 76 patients with rectal ... AIM To introduce a novel,modified primary closure technique of laparoscopic extralevator abdominal perineal excision(LELAPE) for low rectal cancer.METHODS We retrospectively analyzed data from 76 patients with rectal cancer who underwent LELAPE from March 2013 to May 2016.Patients were classified into the modified primary closure group(32 patients) and the biological mesh closure group(44 patients).The total operating time,reconstruction time,postoperative stay duration,total cost,postoperative complications and tumor recur-rence were compared.RESULTS All surgery was successfully performed.The pelvic reconstruction time was 14.6 ± 3.7 min for the modified primary closure group,which was significantly longer than that of the biological mesh closure group(7.2 ± 1.9 min,P < 0.001).The total operating time was not different between the two groups(236 ± 20 min vs 248 ± 43 min,P = 0.143).The postoperative hospital stay duration was 8.1 ± 1.9 d,and the total cost was 9297 ± 1260 USD for the modified primary closure group.Notably,both of these categories were significantly lower in this group than those of the biological mesh closure group(P = 0.001 and P = 0.003,respectively).There were no differences observed between groups when comparing other perioperative data,long-term complications or oncological outcomes.CONCLUSION The modified primary closure method for reconstruction of the pelvic floor in LELAPE for low rectal cancer is technically feasible,safe and cost-effective. 展开更多
关键词 Extralevator abdominoperineal EXCISION RECTAL cancer PELVIC floor LAPAROSCOPY
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Heterotopic ossification beneath the upper abdominal incision after radical gastrectomy:Two case reports 被引量:1
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作者 Xiang Zhang Ping-Tian Xia +2 位作者 Yan-Chao Ma yong dai Yan-Lei Wang 《World Journal of Clinical Cases》 SCIE 2022年第17期5805-5809,共5页
BACKGROUND Heterotopic ossification(HO)is a rare clinical phenomenon that refers to bone formation in nonossifying tissues.CASE SUMMARY This report presents two cases of HO beneath the upper abdominal median incision ... BACKGROUND Heterotopic ossification(HO)is a rare clinical phenomenon that refers to bone formation in nonossifying tissues.CASE SUMMARY This report presents two cases of HO beneath the upper abdominal median incision after radical gastrectomy.The first patient had postoperative pain below the incision area.There were no signs of anastomotic leakage,and the wound healed.Computed tomography(CT)findings 2 wk postoperatively were negative for HO,but the 6-wk CT showed HO beneath the incision.The patient refused reoperation,and after conservative therapy,the pain was gradually relieved after 2 wk.In the second case,postoperative recovery was uneventful,and HO was only detected on routine follow-up CT after 4 mo.An anti-adhesion membrane was applied beneath the peritoneum in both patients.Our findings suggest that HO beneath the abdominal incision might form at approximately 1 mo postoperatively.It may cause intractable pain;however,reoperation is usually not required.CONCLUSION In our cases,we suspect that HO may be related to the use of foreign materials beneath the peritoneum,which needs to be further investigated. 展开更多
关键词 Heterotopic ossification Upper abdominal incision Radical gastrectomy Case report
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Movement characteristics and present seismic activity of Ordos Block 被引量:1
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作者 Lixin Gao Di Hou +4 位作者 Juan Li Shuanhu Li yong dai Feng Xiong Hongying Yang 《Geodesy and Geodynamics》 2016年第6期451-458,共8页
The present horizontal movement of the Ordos Block is the result of the movement interaction between the Ordos Block and the mainland of China. The main dynamic sources are the northeastern pushing by Qinghai-Tibet Bl... The present horizontal movement of the Ordos Block is the result of the movement interaction between the Ordos Block and the mainland of China. The main dynamic sources are the northeastern pushing by Qinghai-Tibet Block, and the northwestern extension of the northern margin of the block. The latest GPS velocity field observational evidences shows that the velocity fie]d of Ordos Block and around has a significant change from 1999 to 2015, and the change is significant in the northeast margin, the northwest margin, the southwest margin, and the southeast margin of the block. The velocity of left lateral movement of the northsouthern margin of Ordos Block is much larger than the right lateral movement of its eastsouthern margin. By using the seismic data of Ordos Block since 1970, the analysis of strain accumulation, strain release, stress distribution, and stress field show that the northern margin of Ordos Block is the main active area not only in the block edge, but also in North China. The strain around Ordos Block has been accu- mulating continuously since 2000, and this is the longest period of strain accumulation since 1970. Some signs of strain relief appeared after Alashanzuoqi Ms5.8 earthquake in 2015. There are some areas with extremely large strain anomalies appear in the northern margin of Ordos Block. 展开更多
关键词 Ordos BlockMovement characteristicsDynamic sourceEarthquakeSeismic activity
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Expression profiling of immune cells in systemic lupuserythematosus by single-cell RNA sequencing
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作者 XIANLIANG HOU DONGE TANG +8 位作者 FENGPING ZHENG MINGLIN OU yong XU HUIXUAN XU XIAOPING HONG XINZHOU ZHANG WEIER dai DONGZHOU LIU yong dai 《BIOCELL》 SCIE 2020年第4期559-582,共24页
Systemic lupus erythematosus(SLE)is a systemic autoimmune disease characterized by abnormal cellular and humoral immune responses and excessive autoantibody production.The precise pathologic mechanism of SLE remains e... Systemic lupus erythematosus(SLE)is a systemic autoimmune disease characterized by abnormal cellular and humoral immune responses and excessive autoantibody production.The precise pathologic mechanism of SLE remains elusive.The advent of single-cell RNA sequencing(scRNA-seq)enables unbiased analysis of the molecular differences of cell populations at the single-cell level.We used scRNA-seq to profile the transcriptomes of peripheral blood mononuclear cells from an SLE patient compared with a healthy control(HC).A total of 16,021 cells were analyzed and partitioned into 12 distinct clusters.The marker genes of each cluster and the four major immune cell types(B cells,CD4+T cells,CD8+T cells,myeloid cells,and NK cells)were determined.Moreover,several genes involved in antigen processing and presentation through MHCII were highly enriched.GO enrichment analyses revealed abnormal gene expression patterns and signaling pathways in SLE.Of note,pseudotime analysis revealed that there was a different lineage hierarchy in the peripheral blood mononuclear cells(PBMCs)of the SLE patient,indicating that the cell states were substantially altered under disease conditions.Our analysis provides a comprehensive map of the cell types and states of the PBMCs of SLE patients at the single-cell level for a better understanding of the pathogenesis,diagnosis,and treatment of SLE. 展开更多
关键词 B cell Differential expression genes Gene ontologies MONOCYTES SYSTEMIC LUPUS ERYTHEMATOSUS SINGLE-CELL RNA-sequencing
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Duodenal-jejunal bypass reduces serum ceramides via inhibiting intestinal bile acid-farnesoid X receptor pathway
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作者 Zhi-Qiang Cheng Tong-Ming Liu +4 位作者 Peng-Fei Ren Chang Chen Yan-Lei Wang yong dai Xiang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2022年第31期4328-4337,共10页
BACKGROUND Bile acids play an important role in the amelioration of type 2 diabetes following duodenal-jejunal bypass(DJB).Serum bile acids are elevated postoperatively.However,the clinical relevance is not known.Bile... BACKGROUND Bile acids play an important role in the amelioration of type 2 diabetes following duodenal-jejunal bypass(DJB).Serum bile acids are elevated postoperatively.However,the clinical relevance is not known.Bile acids in the peripheral circulation reflect the amount of bile acids in the gut.Therefore,a further investigation of luminal bile acids following DJB is of great significance.AIM To investigate changes of luminal bile acids following DJB.METHODS Salicylhydroxamic acid(SHAM),DJB,and DJB with oral chenodeoxycholic acid(CDCA)supplementation were performed in a high-fat-diet/streptozotocininduced diabetic rat model.Body weight,energy intake,oral glucose tolerance test,luminal bile acids,serum ceramides and intestinal ceramide synthesis were analyzed at week 12 postoperatively.RESULTS Compared to SHAM,DJB achieved rapid and durable improvement in glucose tolerance and led to increased total luminal bile acid concentrations with preferentially increased proportion of farnesoid X receptor(FXR)-inhibitory bile acids within the common limb.Intestinal ceramide synthesis was repressed with decreased serum ceramides,and this phenomenon could be partially antagonized by luminal supplementation of FXR activating bile acid CDCA.CONCLUSION DJB significantly changes luminal bile acid composition with increased proportion FXR-inhibitory bile acids and reduces serum ceramide levels.There observations suggest a novel mechanism of bile acids in metabolic regulation after DJB. 展开更多
关键词 Bariatric surgery Duodenal-jejunal bypass Farnesoid X receptor CERAMIDE Bile acids Liver fat accumulation
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A New Variant of Combined Pulmonary Fibrosis and Emphysema from Long-Term High-Dose of Glucocorticoid Therapy: A Case Report
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作者 Qigang Zeng Chenxia Duan yong dai 《Case Reports in Clinical Medicine》 2017年第12期301-307,共7页
Recent studies have described the combination of both pulmonary emphysema and idiopathic interstitial lung disease (ILDs) by means of high-resolution computed axial tomography (HRCT). Definition of this syndrome was f... Recent studies have described the combination of both pulmonary emphysema and idiopathic interstitial lung disease (ILDs) by means of high-resolution computed axial tomography (HRCT). Definition of this syndrome was first named by Cottin as combined pulmonary fibrosis and emphysema (CPFE). Functional and radiological findings have showed that these patients are suffering from severe breathlessness, but whose pulmonary functional tests revealed no signs of obstruction, normal static lung volumes, and depressed DLco, most with a history of smoking [1] [2]. The radiological and endoscopic studies especially show that these patients have both areas of upper-lobe predominant emphysema and lesions compatible with fibrosis in both lung bases [3]. No prior research has reported any cases of such condition in person with no prior history of smoking as well as long-term high-dose of glucocorticoid therapy. In this case report, we discuss the presentation, diagnosis, and management of a 53-year-old non-smoker with increasing shortness of breath with a long-term high-dose of glucocorticoid therapy discovered to have an abnormal variant or presentation of CPFE. The cause of disease was attributed to a certain history of smoking in most studies;other potential risk factors have yet to be properly analyzed. This clinical report features a special case about the problem and solution surrounding this issue. 展开更多
关键词 EMPHYSEMA PULMONARY FIBROSIS HIGH-DOSE of GLUCOCORTICOID Therapy Lung Diseases
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Liver Transplantation from Donation after Cardiac Death
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作者 Weiguo Sui Xianliang Hou +3 位作者 Wenti Che Jiejing Chen Can Zheng yong dai 《器官移植内科学杂志》 2014年第1期1-11,共11页
关键词 移植免疫学 肝脏 死亡 心脏 器官功能 器官移植 生活质量 医疗费用
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Transcription Factor in Patients with Acute Renal Allograft Rejection
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作者 Weiguo Sui Hua Lin +4 位作者 Wujian Peng Yuanshuai Huang Jiejing Chen Yue Zhang yong dai 《器官移植内科学杂志》 2014年第2期45-53,共9页
关键词 转录因子 排斥反应 肾移植 急性 MICRORNA 非编码RNA 蛋白质组学 患者
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Liver Transplantation from Donation after Cardiac Death
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作者 Weiguo Sui Xianliang Hou +3 位作者 Wenti Che Jiejing Chen Can Zheng yong dai 《器官移植内科学杂志》 2014年第3期85-96,共12页
关键词 移植免疫学 死亡 心脏 肝脏 器官功能 器官移植 生活质量 生存率
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Serum Proteomic Study of Patients with Antibody-Mediated Chronic Rejection
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作者 Weiguo Sui Qiang Yan +2 位作者 liling Huang yong dai Jiejing Chen 《器官移植内科学杂志》 2013年第4期124-135,共12页
关键词 排斥反应 蛋白质组学 基质辅助激光解吸电离质谱 介导 抗体 血清 患者 慢性
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Face the Challenge of Organ Donation
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作者 Weiguo Sui Can Zheng +1 位作者 Ming Yang yong dai 《器官移植内科学杂志》 2013年第4期117-123,共7页
关键词 器官移植 肾移植 生存时间 存活时间 学术交流 肝移植 中国 HMG
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Serum Proteomics Profile of Renal Allograft Rejection by Combination of Magnetic Bead Sample Isolation and MALDI- TOF MS
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作者 Weiguo Sui Liling Huang +3 位作者 yong dai Jiejing Chen Qiang Yan He Huang 《器官移植内科学杂志》 2009年第1期1-13,共13页
关键词 器官移植术 肾脏移植物 临床 医学
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Altered Th1/Th2 and Pro-inflammatory Cytokine Profiles in Patients with End Stage Renal Disease Detected by Suspension Array Technology
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作者 Weiguo Sui Jiefeng Tan +2 位作者 Junjun Guo Guizhi Du yong dai 《器官移植内科学杂志》 2008年第1期17-22,共6页
关键词 细胞因子 晚期肾病 临床分析 患者
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Differential MicroRNA Expression Profile in Chronic Rejection of Renal Transplantation
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作者 Weiguo Sui yong dai +3 位作者 YuanShuai Huang Huijuan Lan Qiang Yan He Huang 《器官移植内科学杂志》 2007年第4期200-207,共8页
关键词 肾脏 移植手术 基因 核糖核酸
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Asymmetric copolyimide membranes fabricated by nonsolvent-induced phase separation for He/CH_(4) and He/N_(2) separation
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作者 Ying Li Lu Wang +3 位作者 Junyan Xie yong dai Xuehong Gu Xuerui Wang 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2024年第4期97-106,共10页
Membrane gas separation is considered an energy-saving technique to extract He from natural gas due to no phase change and room temperature operation.However,the membrane performance was strongly limited by the trade-... Membrane gas separation is considered an energy-saving technique to extract He from natural gas due to no phase change and room temperature operation.However,the membrane performance was strongly limited by the trade-off between permeance and selectivity.Herein,novel 4,4′-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)-2,2′-bis(3-amino-4-hydroxyphenyl)hexafluoropropane(APAF)-5-amino-2-(4-aminobenzene)benzimidazole(BIA)asymmetric membranes with a thickness of 300 nm were successfully prepared by the non-solvent induced phase separation method.The membrane performance was modulated by regulating dope solution compositions(e.g.,tetrahydrofuran and polymer concentration).The ideal He/CH_(4) selectivity was 124 and the optimized He permeance reached 87 GPU,beyond the current upper bound.He/CH_(4) selectivity was 75 and He permeance was 73 GPU for the binary mixture feed containing 0.2 mol%He.The membrane showed good resistance to CO_(2) and C_(2)H_(6),which are the typical impurities in natural gas.The 6FDA-APAF-BIA membranes have good stability(>160 h),which can provide great potential in He extraction from natural gas. 展开更多
关键词 He separation membrane natural gas COPOLYIMIDE
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Stability prediction of underground entry-type excavations based on particle swarm optimization and gradient boosting decision tree 被引量:1
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作者 Jian Zhou Shuai Huang +3 位作者 Ming Tao Manoj Khandelwal yong dai Mingsheng Zhao 《Underground Space》 SCIE EI CSCD 2023年第2期234-249,共16页
The stability of underground entry-type excavations will directly affect the working environment and the safety of staff.Empirical critical span graphs and traditional statistics learning methods can not meet the requ... The stability of underground entry-type excavations will directly affect the working environment and the safety of staff.Empirical critical span graphs and traditional statistics learning methods can not meet the requirements of high accuracy for stability assessment of entry-type excavations.Therefore,this study proposes a new prediction method based on machine learning to scientifically adjust the critical span graph.Accordingly,the particle swarm optimization(PSO)algorithm is used to optimize the core parameters of the gradient boosting decision tree(GBDT),abbreviated as PSO-GBDT.Moreover,the classification performance of eight other classifiers including GDBT,k-nearest neighbors(KNN),two kinds of support vector machines(SVM),Gaussian naive Bayes(GNB),logistic regression(LR)and linear discriminant analysis(LDA)are also applied to compare with the proposed model.Findings revealed that compared with the other eight models,the prediction performance of PSO-GBDT is undoubtedly the most reliable,and its classification accuracy is up to 0.93.Therefore,this model has great potential to provide a more scientific and accurate choice for the stability prediction of underground excavations.In addition,each classification model is used to predict the stability category of several grid points divided by the critical span graph,and the updated critical span graph of each model is discussed in combination with previous studies.The results show that the PSO-GBDT model has the advantages of being scientific,accurate and efficient in updating the critical span graph,and its output decision boundary has strict theoretical support,which can help mine operators make favorable economic decisions. 展开更多
关键词 Stability Entry-type excavations Critical span graph Gradient boosting decision tree Particle swarm optimization
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