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Establishment and validation of a predictive model for peripherally inserted central catheter-related thrombosis in patients with liver cancer 被引量:1
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作者 Xiao-Fei Chen Hao-Jun Wu +3 位作者 Tang Li Jia-Bin Liu Wen-Jie Zhou Qiang Guo 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2221-2231,共11页
BACKGROUND Peripherally inserted central catheters(PICCs)are commonly used in hospitalized patients with liver cancer for the administration of chemotherapy,nutrition,and other medications.However,PICC-related thrombo... BACKGROUND Peripherally inserted central catheters(PICCs)are commonly used in hospitalized patients with liver cancer for the administration of chemotherapy,nutrition,and other medications.However,PICC-related thrombosis is a serious complication that can lead to morbidity and mortality in this patient population.Several risk factors have been identified for the development of PICC-related thrombosis,including cancer type,stage,comorbidities,and catheter characteristics.Understanding these risk factors and developing a predictive model can help healthcare providers identify high-risk patients and implement preventive measures to reduce the incidence of thrombosis.AIM To analyze the influencing factors of PICC-related thrombosis in hospitalized patients with liver cancer,construct a predictive model,and validate it.METHODS Clinical data of hospitalized patients with liver cancer admitted from January 2020 to December 2023 were collected.Thirty-five cases of PICC-related thrombosis in hospitalized patients with liver cancer were collected,and 220 patients who underwent PICC placement during the same period but did not develop PICC-related thrombosis were randomly selected as controls.A total of 255 samples were collected and used as the training set,and 77 cases were collected as the validation set in a 7:3 ratio.General patient information,case data,catheterization data,coagulation indicators,and Autar Thrombosis Risk Assessment Scale scores were analyzed.Univariate and multivariate unconditional logistic regression analyses were performed on relevant factors,and the value of combined indicators in predicting PICC-related thrombosis in hospitalized patients with liver cancer was evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Univariate analysis showed statistically significant differences(P<0.05)in age,sex,Karnofsky performance status score(KPS),bedridden time,activities of daily living impairment,parenteral nutrition,catheter duration,distant metastasis,and bone marrow suppression between the thrombosis group and the non-thrombosis group.Other aspects had no statistically significant differences(P>0.05).Multivariate regression analysis showed that age≥60 years,KPS score≤50 points,parenteral nutrition,stage III to IV,distant metastasis,bone marrow suppression,and activities of daily living impairment were independent risk factors for PICC-related thrombosis in hospitalized patients with liver cancer(P<0.05).Catheter duration of 1-6 months and catheter duration>6 months were protective factors for PICC-related thrombosis(P<0.05).The predictive model for PICC-related thrombosis was obtained as follows:P predictive probability=[exp(Logit P)]/[1+exp(Logit P)],where Logit P=age×1.907+KPS score×2.045+parenteral nutrition×9.467+catheter duration×0.506+tumor-node-metastasis(TNM)staging×2.844+distant metastasis×2.065+bone marrow suppression×2.082+activities of daily living impairment×13.926.ROC curve analysis showed an area under the curve(AUC)of 0.827(95%CI:0.724-0.929,P<0.001),with a corresponding optimal cut-off value of 0.612,sensitivity of 0.755,and specificity of 0.857.Calibration curve analysis showed good consistency between the predicted occurrence of PICC-related thrombosis and actual occurrence(P>0.05).ROC analysis showed AUCs of 0.888 and 0.729 for the training and validation sets,respectively.CONCLUSION Age,KPS score,parenteral nutrition,TNM staging,distant metastasis,bone marrow suppression,and activities of daily living impairment are independent risk factors for PICC-related thrombosis in hospitalized patients with liver cancer,while catheter duration is a protective factor for the disease.The predictive model has an AUC of 0.827,indicating high predictive accuracy and clinical value. 展开更多
关键词 Liver cancer Peripherally inserted central catheters THROMBOSIS Model Verify
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Lower extremity peripherally inserted central catheter placement ectopic to the ascending lumbar vein:A case report 被引量:1
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作者 Xiao-Ju Zhu Ling Zhao +2 位作者 Na Peng Jia-Min Luo Shui-Xia Liu 《World Journal of Clinical Cases》 SCIE 2024年第8期1430-1436,共7页
BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients... BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients with superior vena cava syndrome(SVCS).We report the case of a patient with a lower extremity PICC ectopic to the ascending lumbar vein,to indicate and verify PICC catheterisation in the lower extremity is safe and feasible.And hope to provide different per-spectives for clinical PICC venipuncture to get the attention of peers.CASE SUMMARY On 24 August 2022,a 58-year-old male was admitted to our department due to an intermittent cough persisting for over a month,which worsened 10 d prior.Imaging and laboratory investigations suggested the patient with pulmonary malignancy and SVCS.Chemotherapy was not an absolute contraindication in this patient.Lower extremity venipuncture is the preferred technique because administering upper extremity venous transfusion to patients with SVCS can exacerbate oedema in the head,neck,and upper extremities.The patient and his family were informed about the procedure,and informed consent was obtained.After successful puncture and prompt treatment,the patient was discharged,experiencing some relief from symptoms.CONCLUSION Inferior vena cava catheterisation is rare and important for cancer patients with SVCS,particularly in complex situations involving ectopic placement. 展开更多
关键词 Superior vena cava syndrome Peripherally inserted central catheter Ascending lumbar vein COMPLICATIONS Case report
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Esophageal inserted subclavian catheter:a rare complication
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作者 DilberÜçöz Kocaşaban SertaçGüler 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期243-245,共3页
Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemake... Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemakers in intensive care units and all specialties,from anesthesia to emergency medicine,for the treatment of trauma and hemodynamically unstable pediatric and adult patients.[1,2]Complications have been observed in more than 15% of patients who underwent CVC.Mechanical,infectious,and thrombotic complications have been reported in 5%–19%,5%–26%,and 2%–26% of patients,respectively.[3] Malposition,on the other hand,is common in subclavian catheter insertion and is usually associated with an initially misplaced guidewire.[4] 展开更多
关键词 UNSTABLE insertION initially
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A Novel Insertion Solution for the Travelling Salesman Problem
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作者 Emmanuel Oluwatobi Asani Aderemi Elisha Okeyinka +5 位作者 Sunday Adeola Ajagbe Ayodele Ariyo Adebiyi Roseline Oluwaseun Ogundokun Temitope Samson Adekunle Pragasen Mudali Matthew Olusegun Adigun 《Computers, Materials & Continua》 SCIE EI 2024年第4期1581-1597,共17页
The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) a... The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine.The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and NNH.This guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match tothe optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing currentinsertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also createsnew possibilities for progress in heuristic design and optimization methodologies. 展开更多
关键词 Nearest neighbour heuristic farthest insertion heuristic half max insertion heuristic tour construction travelling salesman problem
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Production of Light Fraction-Based Pyrolytic Fuel from Spirulina platensis Microalgae Using Various Low-Cost Natural Catalysts and Insertion
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作者 Indra Mamad Gandidi Sukarni Sukarni +4 位作者 Avita Ayu Permanasari Purnami Purnami TuanAmran Tuan Abdullah Anwar Johari Nugroho Agung Pambudi 《Energy Engineering》 EI 2024年第12期3635-3648,共14页
The use of catalysts has significantly enhanced the yield and quality of in-situ pyrolysis products.However,there is a lack of understanding regarding pyrolysis approaches that utilize several low-cost natural catalys... The use of catalysts has significantly enhanced the yield and quality of in-situ pyrolysis products.However,there is a lack of understanding regarding pyrolysis approaches that utilize several low-cost natural catalysts(LCC)and their placement within the reactor.Therefore,this study aims to examine the effects of various LCC on the insitu pyrolysis of spirulina platensis microalgae(SPM)and investigate the impact of different types of catalysts.We employed LCCsuch as zeolite,dolomite,kaolin,and activated carbon,with both layered and uniformlymixed LCCSPM placements.Each experiment was conducted at a constant temperature of 500℃for 60 min.The resulting pyrolytic liquids(bio-oil)and syngas were analyzed using a Gas Chromatography Mass Spectrometry(GC-MS)analyzer to determine the distribution of hydrocarbon compounds.The experimental results indicated that the presence of catalysts significantly influenced the mass yield productivity of liquid fuels and syngas.Activated carbon and zeolite were preferred among the four catalysts for producing liquid fuels(22.4 and 18.6 wt%)when layered and uniformly mixed,respectively.Kaolin with a layered mixture with SPM was more suitable for the production of light fractions(C_(5)–C_(12)),achieving approximately 95.7%peak area,while zeolite with a uniform mixture produced the highest light fraction at about 86.3%peak area.All catalysts except kaolin significantly increased the aromatic compounds in the liquid fuels.Although the amount of oxygenated hydrocarbons in the bio-oil remained relatively high,the final hydrocarbon composition was highly comparable to conventional fuels such as gasoline-88,which has a C_(5)–C_(12)hydrocarbon distribution of approximately 88.1%peak area.Regarding the syngas products,all catalysts except activated carbon successfully converted nitromethane compounds into tetranitromethane hydrocarbons,with activated carbon predominantly yielding nitromethane compounds. 展开更多
关键词 Pyrolysis in-situ SPM LCC BIO-OIL SYNGAS insertION
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Enhancing hydrogen evolution and oxidation kinetics through oxygen insertion into nickel lattice
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作者 Wanli Liang Xiyu Gong +9 位作者 Jinchang Xu Zixuan Dan Fanyan Xie Hulei Yu Hao-Fan Wang Yanshuo Jin Hongjuan Wang Yonghai Cao Hui Meng Hao Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期529-539,I0012,共12页
Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution rea... Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution reaction(HER)and hydrogen oxidation reaction(HOR).In this paper,an oxygen insertion strategy was applied on nickel to regulate its hydrogen electrocatalytic performance,and the oxygen-inserted nickel catalyst was successfully obtained with the assistance of tungsten dioxide support(denoted as O-Ni/WO_(2)).The partial insertion of oxygen in Ni maintains the face-centered cubic arrangement of Ni atoms,simultaneously expanding the lattice and increasing the lattice spacing.Consequently,the adsorption strength of^(*)H and^(*)OH on Ni is optimized,thus resulting in superior electrocatalytic performance of0-Ni/WO_(2)in alkaline HER/HOR.The Tafel slope of O-Ni/WO_(2)@NF for HER is 56 mV dec^(-1),and the kinetic current density of O-Ni/WO_(2)for HOR reaches 4.85 mA cm^(-2),which is ahead of most currently reported catalysts.Our proposed strategy of inserting an appropriate amount of anions into the metal lattice could provide more possibilities for the design of high-performance catalysts. 展开更多
关键词 Hydrogen evolution Hydrogen oxidation NICKEL Oxygen insertion Adsorption free energy
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Identification and characterization of FpRco1 in regulating vegetative growth and pathogenicity based on T-DNA insertion in Fusarium pseudograminearum
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作者 Haiyang Li Yuan Zhang +18 位作者 Cancan Qin Zhifang Wang Lingjun Hao Panpan Zhang Yongqiang Yuan Chaopu Ding Mengxuan Wang Feifei Zan Jiaxing Meng Xunyu Zhuang Zheran Liu Limin Wang Haifeng Zhou Linlin Chen Min Wang Xiaoping Xing Hongxia Yuan Honglian Li Shengli Ding 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3055-3065,共11页
Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.... Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.pseudograminearum infects wheat remains unclear.In this study,we aimed to elucidate these mechanisms by constructing a T-DNA insertion mutant library for the highly virulent strain WZ-8A of F.pseudograminearum.By screening this mutant library,we identified nine independent mutants that displayed impaired pathogenesis in barley leaves.Among these mutants,one possessed a disruption in the gene FpRCO1 that is an ortholog of Saccharomyces cerevisiae RCO1,encoding essential component of the Rpd3S histone deacetylase complex in F.pseudograminearum.To further investigate the role of FpRCO1 in F.pseudograminearum,we employed a split-marker approach to knock out FpRCO1 in F.pseudograminearum WZ-8A.FpRCO1 deletion mutants exhibit reduced vegetative growth,conidium production,and virulence in wheat coleoptiles and barley leaves,whereas the complementary strain restores these phenotypes.Moreover,under stress conditions,the FpRCO1 deletion mutants exhibited increased sensitivity to NaCl,sorbitol,and SDS,but possessed reduced sensitivity to H_(2)O_(2)compared to these characteristics in the wild-type strain.RNA-seq analysis revealed that deletion of FpRCO1 affected gene expression(particularly the downregulation of TRI gene expression),thus resulting in significantly reduced deoxynivalenol(DON)production.In summary,our findings highlight the pivotal role of FpRCO1 in regulating vegetative growth and development,asexual reproduction,DON production,and pathogenicity of F.pseudograminearum.This study provides valuable insights into the molecular mechanisms underlying F.pseudograminearum infection in wheat and may pave the way for the development of novel strategies to combat this devastating disease. 展开更多
关键词 Fusarium pseudograminearum T-DNA insertion Rpd3S complex FpRCO1 PATHOGENICITY DON production
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An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica
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作者 Zhongyi ZHANG Hang LIU +5 位作者 Xiaohui PAN Yanan ZONG Leili FENG Lixian LIU Li GUO Guanpin YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期216-225,共10页
Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-st... Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species. 展开更多
关键词 Nannochloropsis oceanica genetic transformation random insertional mutant library zeocin pretreatment forward genetics
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Velamentous Cord Insertion: Interest of Antenatal Diagnosis and Review of the Literature
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作者 Karam Harou Aboubacar Sidiki Sidibe +1 位作者 Hicham Abdelkhalki Abderaouf Soummani 《Open Journal of Obstetrics and Gynecology》 2024年第2期234-239,共6页
Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be d... Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be diagnosed during the morphological ultrasound of the 2nd trimester, actively looking for the association with a vasa previa, due to the risk of fetal haemorrhagic threat. We report an antenatal diagnosis of velamentous cord insertion and its management with literature review. 展开更多
关键词 Velamentous Cord insertion Vasa Previa Antenatal Diagnosis Ultrasound Doppler Benckiser’s Hemorrhage
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Tubular Heat Enhancement Using Twisted Tape Inserts with Large Holes
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作者 Ali Jaber Abdulhamed Aws Al-Akam +1 位作者 Wisam J.Khudhayer Ali Sabri Allw 《Energy Engineering》 EI 2024年第2期273-290,共18页
Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fi... Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fillers inside the tubes to enhance heat transfer.This investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting factor.In the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular cross-section.The turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was constructed.The findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as well.Additionally,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably higher.Additionally,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube values.The maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated. 展开更多
关键词 TUBULAR heat exchanger tape inserts twisted tape
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Treatment of benign rectal stricture caused by repeated anal insertion by endoscopy and balloon dilation:A case report
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作者 Shih-Hung Liu Jung-Cheng Kang +3 位作者 Je-Ming Hu Chao-Yang Chen Kuan-Hsun Lin Ta-Wei Pu 《World Journal of Gastrointestinal Endoscopy》 2024年第2期91-97,共7页
BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have dive... BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have diverse etiologies,including various inflammatory conditions.Benign strictures are usually managed by surgery and endoscopy.We present an unusual etiology of benign rectal stricture caused by the repeated insertion of foreign objects into the rectum for sexual purposes,resulting in rectal injury and subsequent chronic inflammation.CASE SUMMARY A 53-year-old man presented to the outpatient clinic of the Colorectal Surgery Department with symptoms of chronic constipation and bloody stools.The patient previously experienced rectal injury due to foreign object insertion for sexual purposes.Colonoscopy revealed benign circumferential narrowing of the rectum.He underwent treatment by endoscopic argon plasma coagulation and balloon dilation and follow-up as an outpatient for 4 months.A colonoscopy at the end of the follow-up period revealed no evidence of rectal stricture relapse.CONCLUSION A history of rectal injury,followed by chronic inflammation,should be considered in patients with benign rectal strictures.Management with endoscopic argon plasma coagulation and balloon dilation can prevent the need for surgical resection of benign rectal strictures. 展开更多
关键词 Chronic rectal inflammation COLONOSCOPY Benign rectal stricture Foreign body insertion Rectal injury Case report
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针刀干预后颈椎病大鼠头夹肌成纤维细胞生长因子家族及其受体的表达
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作者 刘福水 钱嘉铭 +4 位作者 方婷 哈留娜 赵小兰 朱金超 王小乐 《中国组织工程研究》 CAS 北大核心 2025年第18期3775-3783,共9页
背景:针刀是治疗颈椎病的有效方法,临床疗效确切,但其关键分子机制尚不明晰。目的:观察针刀干预对颈椎病大鼠头夹肌成纤维细胞生长因子家族及其受体激酶插入域蛋白受体表达的影响,分析针刀治疗颈椎病的作用机制。方法:通过检索GEO数据库... 背景:针刀是治疗颈椎病的有效方法,临床疗效确切,但其关键分子机制尚不明晰。目的:观察针刀干预对颈椎病大鼠头夹肌成纤维细胞生长因子家族及其受体激酶插入域蛋白受体表达的影响,分析针刀治疗颈椎病的作用机制。方法:通过检索GEO数据库,获取符合该研究的芯片数据集GSE153761,采用生物信息学方法进行靶标初筛,然后进行动物实验。选取6月龄SPF级SD大鼠24只,随机均分为4组。模型组和针刀组大鼠采用动静力失衡性颈椎病造模方法制备颈椎病大鼠模型;假手术组不切断肌肉及韧带;针刀组造模成功后采用针刀干预,每周1次,共3次;并以正常大鼠作为对照。拍摄颈椎正侧位X射线片进行模型验证;旷场实验观察大鼠行为学变化;苏木精-伊红染色观察头夹肌病理结构;荧光定量PCR法和免疫组化法分别检测头夹肌成纤维细胞生长因子家族及其受体激酶插入域蛋白受体mRNA及蛋白的表达情况。结果与结论:①生物信息学结果表明成纤维细胞生长因子家族/激酶插入域蛋白受体是激活磷脂酰肌醇3-激酶/蛋白激酶B上游的重要信号轴。②造模后大鼠椎间隙变窄,椎体前后缘、关节突骨质增生。③旷场实验中,造模后大鼠总距离、平均速度降低(P<0.05),总休息时间延长(P<0.05);治疗后针刀组大鼠总距离、平均速度大于模型组(P<0.05),总休息时间短于模型组(P<0.05)。④头夹肌病理提示颈肌受损,而针刀可改善颈肌劳损。⑤与正常组比较,模型组大鼠头夹肌成纤维细胞生长因子7、成纤维细胞生长因子9、成纤维细胞生长因子10、成纤维细胞生长因子18和激酶插入域蛋白受体mRNA及蛋白表达均升高(P<0.05);与模型组比较,针刀组以上指标均降低(P<0.05)。⑥结果说明,针刀可能通过调节成纤维细胞生长因子7、成纤维细胞生长因子9、成纤维细胞生长因子10、成纤维细胞生长因子18及其受体激酶插入域蛋白受体的表达,修复劳损颈肌,从而改善椎间盘退变,这可能是针刀治疗颈椎病的关键靶点。 展开更多
关键词 针刀 颈椎病 成纤维细胞生长因子 激酶插入域蛋白受体 工程化细胞因子 工程化组织构建
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Genetic Analysis of a Small Grain Mutant Induced by T-DNA Insertion in Rice 被引量:5
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作者 张向前 朱海涛 +1 位作者 邹金松 曾瑞珍 《Agricultural Science & Technology》 CAS 2008年第3期63-66,91,共5页
[Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-... [Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-DNA tag lines, the progeny of homozygous plants carrying T-DNA insertion were screened for mutants with mutated phenotypes. The genetic analysis of the mutant and test for the linkage between the mutated phenotype and the T-DNA insertion were carried out to determine its genetic characteristics. [Result] In the present study, a grain shape mutant induced by T-DNA insertion in rice was identified, which showed small grain. Genetic analysis of the mutant showed that the two types of phenotype, normal and small grain in the segregating populations derived from the T-DNA heterozygotes, fit the ratio of 3∶1. Test for Basta resistance showed that all the mutants were resistant while the normal plants segregated for resistant and susceptible by the ratio of 2∶1. The results indicated that the mutant phenotype cosegregated with Bar gene. The small grain mutant caused by T-DNA insertion was confirmed by PCR amplification aiming at T-DNA. [Conclusion] The grain shape mutant is useful for isolation of the tagged gene and genetic improvement in rice. 展开更多
关键词 ORYZA SATIVA GRAIN shape MUTANT T-DNA insertion
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高分辨率小动物Micro Insert PET系统的模拟研究 被引量:1
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作者 尹永智 李梅春 +2 位作者 王慧鹏 姚丽萍 叶征乾 《核技术》 CAS CSCD 北大核心 2014年第11期23-28,共6页
在西门子Micro PET小动物成像系统中接入高分辨率的Insert探测器环,组成了Micro Insert PET系统,可以进一步提高小动物PET系统的图像分辨率。本文采用蒙特卡罗模拟软件GATE定义Focus-220小动物PET和Micro Insert两种系统,在同步仿真运算... 在西门子Micro PET小动物成像系统中接入高分辨率的Insert探测器环,组成了Micro Insert PET系统,可以进一步提高小动物PET系统的图像分辨率。本文采用蒙特卡罗模拟软件GATE定义Focus-220小动物PET和Micro Insert两种系统,在同步仿真运算中,给出了三种类型的符合数据,即PET Scanner和PET Scanner之间的符合、PET Scanner和Insert之间的符合、Insert和Insert之间的符合。用滤波反投影算法重建了Na-22单点源模型、多点源模型、LZU模型的PET图像。其中,多点源模型的径向图像分辨率的仿真结果与美国华盛顿大学的Micro Insert实验数据,在忽略正电子射程、非线性效应项以及噪声等的贡献下,两者符合得很好。研究表明,使用Micro Insert系统能够将小动物PET系统的图像分辨率提高到亚毫米水平。 展开更多
关键词 蒙特卡罗仿真 小动物PET MICRO insert系统 图像重建
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Preparation of BCEC-Astrocyte Co-culturing Membrane Plate Insert 被引量:1
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作者 赵康峰 王琪 +2 位作者 蒲小平 杨秀伟 朱玉真 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第4期276-281,共6页
To prepare a hand-made micropore membrane culture plate insert forco-culture. Methods The plate insert was made using plastic centrifuge tube and micropore membrane.After seeding brain capillary endothelial cells (BCE... To prepare a hand-made micropore membrane culture plate insert forco-culture. Methods The plate insert was made using plastic centrifuge tube and micropore membrane.After seeding brain capillary endothelial cells (BCECs) on it (under the effect ofastrocyte-conditioned medium), the plate insert was assessed by analysis of trans-endothelialelectrical resistance (TEER). Results The plate insert has a stability of at least 15 d underculture condition. TEER increased significantly under co-culture condition from (66.1 +- 13.3)Ωcm^2 to (182.2 +- 6.7) Ωcm^2. Conclusion This micropore membrane culture plate insert can beeasily made, on which BCEC culture can be successfully performed. Moreover, it is adjustable andrecyclable. It follows that the plate insert is a useful tool for co-culture and the relatedresearch fields. 展开更多
关键词 blood-brain barrier culture plate insert brain capillary endothelial cell ASTROCYTE trans-endothelial electronic resistance
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Timing Optimization by Inserting Minimum Buffers with Accurate Delay Models
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作者 张轶谦 洪先龙 +1 位作者 周强 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第11期1409-1415,共7页
An algorithm of minimizing the number of buffers under certain delay constraint with accurate delay models is presented.Given a two-terminal net,the algorithm can minimize the total number of buffers inserted to meet ... An algorithm of minimizing the number of buffers under certain delay constraint with accurate delay models is presented.Given a two-terminal net,the algorithm can minimize the total number of buffers inserted to meet the delay constraint.A high order delay model is applied to estimate interconnect delay and a nonlinear delay model based on look-up table is for buffer delay estimation.The experimental results show that the algorithm can efficiently achieve the trade-offs between number of buffers and delay,and avoid needless power and area cost.The running time is satisfactory. 展开更多
关键词 buffer insertion interconnect optimization layout VLSI
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Path-Based Timing Optimization by Buffer Insertion with Accurate Delay Model
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作者 张轶谦 周强 +1 位作者 洪先龙 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期520-525,共6页
An algorithm of path based timing optimization by buffer insertion is presented.The algorithm adopts a high order model to estimate interconnect delay and a nonlinear delay model based on look up table for gate dela... An algorithm of path based timing optimization by buffer insertion is presented.The algorithm adopts a high order model to estimate interconnect delay and a nonlinear delay model based on look up table for gate delay estimation.And heuristic method of buffer insertion is presented to reduce delay.The algorithm is tested by industral circuit case.Experimental results show that the algorithm can optimize the timing of circuit efficiently and the timing constraint is satisfied. 展开更多
关键词 buffer insertion timing optimization interconnect planning routing algorithm
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Parallel EOI algorithm with different insertion schemes
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作者 刘庆富 仲伟俊 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期283-288,共6页
A parallel embedding overlapped iterative (EOI) algorithm about classicimplicit equations with asymmetric Saul'yev schemes (CIS-EOI) to solve one-dimensional diffusionequations is discussed to improve the properti... A parallel embedding overlapped iterative (EOI) algorithm about classicimplicit equations with asymmetric Saul'yev schemes (CIS-EOI) to solve one-dimensional diffusionequations is discussed to improve the properties of the segment classic implicit iterative (SCII)algorithm. The structure of CIS-EOI method is given and the stability of scheme and convergence ofiteration are proved by matrix method. The property of gradual-approach convergence is alsodiscussed. It has been shown that the convergent rate is faster and the property of gradual-approachconvergence also becomes better with the increasing of the net point in subsystems than with theSCII algorithm. The simulation examples show that the parallel iterative algorithm with a differentinsertion scheme CIS-EOI is more effective. 展开更多
关键词 diffusion equation different insertion scheme convergent rate property ofgradual-approach convergence
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Fine-Grain Sleep Transistor Insertion for Leakage Reduction
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作者 杨华中 汪玉林 +1 位作者 海罗嵘 汪蕙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期258-265,共8页
A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mix... A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mixed-integer linear programming (MLP) problem in order to simultaneously place and size the sleep transistors optimally. Because of better circuit slack utilization, our experimental results show that the MLP model can save leakage by 79.75%, 93.56%, and 94.99% when the circuit slowdown is 0%, 3%, and 5%, respectively. The MLP model also achieves on average 74.79% less area penalty compared to the conventional fixed slowdown method when the circuit slowdown is 7%. 展开更多
关键词 leakage current reduction fine-grain sleep transistor insertion delay model mixed-integer linearprogramming
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Needle Steering for Robot-Assisted Insertion into Soft Tissue:A Survey 被引量:7
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作者 GAO Dedong LEI Yong ZHENG Haojun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期629-638,共10页
Needle insertion is a common surgical procedure used in diagnosis and treatment.The needle steering technologies make continuous developments in theoretical and practical aspects along with the in-depth research on ne... Needle insertion is a common surgical procedure used in diagnosis and treatment.The needle steering technologies make continuous developments in theoretical and practical aspects along with the in-depth research on needle insertion.It is necessary to summarize and analyze the existing results to promote the future development of theories and applications of needle insertion.Thus,a survey of the state of the art of research is presented on algorithms of needle steering techniques,the surgical robots and devices.Based on the analysis of the needle insertion procedure,the concept of needle steering is defined as a kinematics problem,which is to place the needle at the target and avoid the obstacles.The needle steering techniques,including the artificial potential field method and the nonholonomic model,are introduced to control the needles for improving the accuracy.Based on the quasi-static thinking,the virtual spring model and the cantilever-beam model are developed to calculate the amount of needle deflection and generate the needle path.The phantoms instead of the real tissue are used to verify the models mentioned in most of the experimentations.For the desired needle trajectories,the image-guided robotic devices and some novel needles are presented to achieve the needle steering.Finally,the challenges are provided involving the controllability of the long flexible needle and the properties of soft tissue.The results and investigations can be used for further study on the precision and accuracy of needle insertion. 展开更多
关键词 needle insertion needle steering robot-assisted needle insertion path planning needle deflection tissue deformation
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