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Women in visual neural regeneration research
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作者 Tonia S.Rex David J.Calkins 《Neural Regeneration Research》 SCIE CAS 2025年第2期489-490,共2页
The year 2024 marks the 60^(th)anniversary of Title IX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts Institute of Technology.We take an opportunity here to exa... The year 2024 marks the 60^(th)anniversary of Title IX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts Institute of Technology.We take an opportunity here to examine the state of gender bias in a relatively new yet already prominent field,neural regeneration in the visual system,for which there is a well-defined context useful for this purpose.The National Eye Institute(NEI)provided the first round of research funding for its Audacious Goals Initiative(AGI)on visual neural regeneration in 2013 and the last round in 2021.Therefore,we focus on this timespan.Data sources included PubMed,the National Science Foundation(NSF),the NEI,the Blue Ridge Institute for Medical Research and data from the major professional organization for eye and vision research,the Association for Research in Vision and Ophthalmology(ARVO). 展开更多
关键词 NEURAL VISUAL TIMES
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Sustainable land management in Mali 被引量:1
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作者 Karim Nchare Marcel Vitouley Richard Mbih 《Geography and Sustainability》 CSCD 2024年第3期382-391,共10页
This study uses logistic and Poisson regression models to examine the factors influencing the adoption of sustain-able land management(SLM)practices in Mali using two rounds of the nationally representative survey Enq... This study uses logistic and Poisson regression models to examine the factors influencing the adoption of sustain-able land management(SLM)practices in Mali using two rounds of the nationally representative survey Enquête Agricole de Conjoncture Intégrée aux Conditions de Vie des Ménages.The SLMs considered include the applica-tion of organic fertilizers,the application of inorganic fertilizers,the use of improved seeds,and the practice of intercropping.On average the application of organic fertilizers(39.2%),and inorganic fertilizers(28.7%)are the most frequent SLM practices among Malian farmers,and between 2014 and 2017,we observe a decline in the practice of intercropping.The regression results show that farmers’adoption of different SLMs is significantly associated with biophysical factors(average temperature,climate type,plot size,plot shape,and location),de-mographic factors(age,gender,education,household size),and socioeconomic factors(number of cultivated plots,livelihood diversification,type of crop grown,market access,credit access,economic shocks,and social capital).Our findings suggest that policymakers and agricultural development agencies in Mali need to adopt a multidimensional policy framework to unlock the untapped potential of SLM practices in promoting sustainable agriculture and food security. 展开更多
关键词 Sustainable land management AFRICA Logistic regression models Poisson regression model
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Implications for brainstem recovery from studies in primates after sensory loss from arm
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作者 Jamie L.Reed Hui-Xin Qi Jon H.Kaas 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期479-480,共2页
For decades,researchers have known that when neurons lose their activating inputs,they can atrophy and even die.For example,removing sensory nerve inputs from the arm to the spinal cord after amputation or cutting the... For decades,researchers have known that when neurons lose their activating inputs,they can atrophy and even die.For example,removing sensory nerve inputs from the arm to the spinal cord after amputation or cutting the spinal nerves can shrink the post-synaptic target zones(e.g.,Woods et al.,2000).From touch receptors for the hand and arm,primary nerve afferents enter the spinal cord,and axons travel in the dorsal columns to target the cuneate nucleus(Cu)of the brainstem on the same side of the body(Figure 1).When sensory loss is unilateral,the overwhelming result is for the associated primary target zone to shrink in total size(cross-sectional area),as compared to the size of the opposite side. 展开更多
关键词 BRAINSTEM shrink removing
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Hepatocellular carcinoma presenting as an extrahepatic mass:A case report and review of literature
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作者 Wei Kelly Wu Krutika Patel +1 位作者 Chandrasekhar Padmanabhan Kamran Idrees 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2241-2252,共12页
BACKGROUND Hepatocellular carcinoma(HCC)is a primary liver tumor generally diagnosed based on radiographic findings.Metastatic disease is typically associated with increased tumor diameter,multifocality,and vascular i... BACKGROUND Hepatocellular carcinoma(HCC)is a primary liver tumor generally diagnosed based on radiographic findings.Metastatic disease is typically associated with increased tumor diameter,multifocality,and vascular invasion.We report a case of a patient who presented with extrahepatic HCC metastasis to a portocaval lymph node with occult hepatic primary on computed tomography(CT).We review the literature for cases of extrahepatic HCC presentation without known hepatic lesions and discuss strategies to differentiate between metastatic and ectopic HCC.CASE SUMMARY A 67-year-old male with remotely treated hepatis C was referred for evaluation of an enlarging portocaval,mixed cystic-solid mass.Serial CT evaluations demonstrated steatosis,but no cirrhosis or liver lesions.Endoscopic ultrasound demonstrated a normal-appearing pancreas,biliary tree,and liver.Fine needle aspiration yielded atypical cells.The differential diagnosis included duodenal or pancreatic cyst,lymphoproliferative cyst,stromal or mesenchymal lesions,nodal involvement from gastrointestinal or hematologic malignancy,or duodenal gastrointestinal stromal tumor.After review by a multidisciplinary tumor board,the patient underwent open surgical resection of a 5.2 cm×5.5 cm retroperitoneal mass with pathology consistent with moderately-differentiated HCC.Magnetic resonance imaging(MRI)subsequently demonstrated a 1.2 cm segment VIII hepatic lesion with late arterial enhancement,fatty sparing,and intrinsic T1 hyperintensity.Alpha fetoprotein was 23.3 ng/mL.The patient was diagnosed with HCC with portocaval nodal involvement.Review:We surveyed the literature for HCC presenting as extrahepatic masses without history of concurrent or prior intrahepatic HCC.We identified 18 cases of extrahepatic HCC ultimately found to represent metastatic lesions,and 30 cases of extrahepatic HCC found to be primary,ectopic HCC.CONCLUSION Hepatocellular carcinoma can seldomly present with extrahepatic metastasis in the setting of occult primary.In patients with risk factors for HCC and lesions suspicious for metastatic disease,MRI may be integral to identifying small hepatic lesions and differentiating from ectopic HCC.Tumor markers may also have utility in establishing the diagnosis. 展开更多
关键词 EXTRAHEPATIC METASTASIS Portocaval Lymph node Case report
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Understanding the educational inequalities in suicide attempts and their mediators:a Mendelian randomisation study
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作者 Jiahao Zhu Houpu Liu +5 位作者 Rui Gao Lilu Ding Jing Wang Ye Yang Dan Zhou Yingjun Li 《General Psychiatry》 CSCD 2024年第1期133-142,共10页
Background Educational inequalities in suicide have become increasingly prominent over the past decade.Elucidating modifiable risk factors that serve as intermediaries in the impact of low educational attainment on su... Background Educational inequalities in suicide have become increasingly prominent over the past decade.Elucidating modifiable risk factors that serve as intermediaries in the impact of low educational attainment on suicide has the potential to reduce health disparities.Aims To examine the risk factors that mediate the relationship between educational attainment and suicide attempts and quantify their contributions to the mediation effect.Methods We conducted a two-sample Mendelian randomisation(MR)analysis to estimate the causal effect of educational attainment on suicide attempts,utilising genome-wide association study summary statistics from the Integrative Psychiatric Research(iPSYCH;6024 cases and 44240 controls)and FinnGen(8978 cases and 368299 controls).We systematically evaluated 42 putative mediators within the causal pathway connecting reduced educational attainment to suicide attempts and employed two-step and multivariable MR to quantify the proportion of the mediated effect.Results In the combined analysis of iPSYCH and FinnGen,each standard deviation(SD)decrease in genetically predicted educational attainment(equating to 3.4 years of education)was associated with a 105%higher risk of suicide attempts(odds ratio(OR):2.05;95%confidence interval(Cl):1.81 to 2.31).0f the 42 risk factors analysed,the two-step MR identified five factors that mediated the association between educational attainment and suicide attempts.The respective proportions of mediation were 47%(95%Cl:29%to 66%)for smoking behaviour,36%(95%Cl:0%to 84%)for chronic pain,49%(95%Cl:36%to 61%)for depression,35%(95%Cl:12%to 59%)for anxiety and 26%(95%Cl:18%to 34%)for insomnia.Multivariable MR implicated these five mediators collectively,accounting for 68%(95%Cl:40%to 96%)of the total effect.Conclusions This study identified smoking,chronic pain and mental disorders as primary intervention targets for attenuating suicide risk attributable to lower educational levels in the European population. 展开更多
关键词 effect. RANDOM INEQUALITIES
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Bifurcation Analysis Reveals Solution Structures of Phase Field Models
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作者 Xinyue Evelyn Zhao Long-Qing Chen +1 位作者 Wenrui Hao Yanxiang Zhao 《Communications on Applied Mathematics and Computation》 EI 2024年第1期64-89,共26页
The phase field method is playing an increasingly important role in understanding and predicting morphological evolution in materials and biological systems.Here,we develop a new analytical approach based on the bifur... The phase field method is playing an increasingly important role in understanding and predicting morphological evolution in materials and biological systems.Here,we develop a new analytical approach based on the bifurcation analysis to explore the mathematical solution structure of phase field models.Revealing such solution structures not only is of great mathematical interest but also may provide guidance to experimentally or computationally uncover new morphological evolution phenomena in materials undergoing electronic and structural phase transitions.To elucidate the idea,we apply this analytical approach to three representative phase field equations:the Allen-Cahn equation,the Cahn-Hilliard equation,and the Allen-Cahn-Ohta-Kawasaki system.The solution structures of these three phase field equations are also verified numerically by the homotopy continuation method. 展开更多
关键词 Phase field modeling BIFURCATIONS Multiple solutions
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Measuring Pedestrian Stress Response (MPSR) Using Wearable Technologies
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作者 Ishita Dash Rachael Anne Muscatello +2 位作者 Mark D. Abkowitz Ella R. Mostoller Mike Sewell 《Journal of Transportation Technologies》 2024年第2期224-235,共12页
Walkability is an essential aspect of urban transportation systems. Properly designed walking paths can enhance transportation safety, encourage pedestrian activity, and improve community quality of life. This, in tur... Walkability is an essential aspect of urban transportation systems. Properly designed walking paths can enhance transportation safety, encourage pedestrian activity, and improve community quality of life. This, in turn, can help achieve sustainable development goals in urban areas. This pilot study uses wearable technology data to present a new method for measuring pedestrian stress in urban environments and the results were presented as an interactive geographic information system map to support risk-informed decision-making. The approach involves analyzing data from wearable devices using heart rate variability (RMSSD and slope analysis) to identify high-stress locations. This data-driven approach can help urban planners and safety experts identify and address pedestrian stressors, ultimately creating safer, more walkable cities. The study addresses a significant challenge in pedestrian safety by providing insights into factors and locations that trigger stress in pedestrians. During the pilot study, high-stress pedestrian experiences were identified due to issues like pedestrian-scooter interaction on pedestrian paths, pedestrian behavior around high foot traffic areas, and poor visibility at pedestrian crossings due to inadequate lighting. 展开更多
关键词 Wearable Technology WALKABILITY Built Environment Pedestrian Safety
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Quasi-Static, Poiseuille Flow of Analgesics from an Elastomeric Pump: Theoretical Determination of Infusion Times and Toxicity Conditions
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作者 Clare B. Lipscombe Trevor C. Lipscombe Don S. Lemons 《Journal of Biosciences and Medicines》 2024年第9期251-265,共15页
Background: Elastomeric pumps (elastic balls into which analgesics or antibiotics can be inserted) push medicines through a catheter to a nerve or blood vessel. Since elastomeric pumps are small and need no power sour... Background: Elastomeric pumps (elastic balls into which analgesics or antibiotics can be inserted) push medicines through a catheter to a nerve or blood vessel. Since elastomeric pumps are small and need no power source, they fit easily into a pocket during infusion, allowing patient mobility. Elastomeric pumps are widely used and widely studied experimentally, but they have well-known problems, such as maintaining reliable flow rates and avoiding toxicity or other peak-and-trough effects. Objectives: Our research objective is to develop a realistic theoretical model of an elastomeric pump, analyze its flow rates, determine its toxicity conditions, and otherwise improve its operation. We believe this is the first such theoretical model of an elastomeric pump consisting of an elastic, medicine-filled ball attached to a horizontal catheter. Method: Our method is to model the system as a quasi-Poiseuille flow driven by the pressure drop generated by the elastic sphere. We construct an engineering model of the pressure exerted by an elastic sphere and match it to a solution of the one-dimensional radial Navier-Stokes equation that describes flow through a horizontal, cylindrical tube. Results: Our results are that the model accurately reproduces flow rates obtained in clinical studies. We also discover that the flow rate has an unavoidable maximum, which we call the “toxicity bump”, when the radius of the sphere approaches its terminal, unstretched value—an effect that has been observed experimentally. Conclusions: We conclude that by choosing the properties of an elastomeric pump, the toxicity bump can be restricted to less than 10% of the earlier, relatively constant flow rate. Our model also produces a relation between the length of time that the analgesic fluid infuses and the physical properties of the fluid, of the elastomeric sphere and the tube, and of the blood vessel into which the analgesic infuses. From these, we conclude that elastomeric pumps can be designed, using our simple model, to control infusion times while avoiding toxicity effects. 展开更多
关键词 Elastomeric Pump Infusion Therapy Bio-Fluids Medical Devices Antibiotic Delivery Analgesic Delivery
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Sarcopenic obesity in patients awaiting liver transplant: Unique challenges for nutritional recommendations
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作者 Darya M Herscovici Katherine M Cooper +3 位作者 Alessandro Colletta Michelle Rightmyer Alexandra Shingina Lauren D Feld 《World Journal of Transplantation》 2024年第2期40-47,共8页
Sarcopenic obesity increases the risk of mortality in patients with liver disease awaiting liver transplantation and in the post-transplant period.Nutrition recommendations for individuals with sarcopenia differ from ... Sarcopenic obesity increases the risk of mortality in patients with liver disease awaiting liver transplantation and in the post-transplant period.Nutrition recommendations for individuals with sarcopenia differ from recommendations for patients with obesity or sarcopenic obesity.While these nutrition guidelines have been established in non-cirrhotic patients,established guidelines for liver transplant candidates with sarcopenic obesity are lacking.In this paper,we review existing literature on sarcopenic obesity in patients with chronic liver disease and address opportunities to improve nutritional counseling in patients awaiting liver transplantation. 展开更多
关键词 NUTRITION SARCOPENIA Sarcopenic obesity Liver transplant CIRRHOSIS Chronic liver disease Body composition MYOSTATIN
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Lu-Hf年代学研究——以大别榴辉岩为例 被引量:23
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作者 袁洪林 高山 +4 位作者 罗彦 宗春蕾 戴梦宁 柳小明 第五春荣 《岩石学报》 SCIE EI CAS CSCD 北大核心 2007年第2期233-239,共7页
本文利用多接收电感耦合等离子体质谱仪(MC-ICP-MS)进行了同位素稀释法Lu-Hf年代学研究,建立了全岩Lu、Hf的分离条件。分离后Lu溶液中^(176)Lu/^(176)Yb大于30,分离后Hf溶液中Lu和Yb对Hf的干扰(^(176)Lu/^(176)Hf和^(176)Yb/^(176)Hf分... 本文利用多接收电感耦合等离子体质谱仪(MC-ICP-MS)进行了同位素稀释法Lu-Hf年代学研究,建立了全岩Lu、Hf的分离条件。分离后Lu溶液中^(176)Lu/^(176)Yb大于30,分离后Hf溶液中Lu和Yb对Hf的干扰(^(176)Lu/^(176)Hf和^(176)Yb/^(176)Hf分别小于2×10^(-6)和2×10^(-4))采用指数法则进行校正。建立了MC-ICP-MS进行Lu、Hf同位素高精度准确测试的校正方法。天然样品中Hf同住素^(176)Hf/^(177)Hf的内部测试精度优于0.0015%,外部精密度优于0.0010%。应用本文建立的方法获得大别双河榴辉岩石榴子石-全岩Lu-Hf等时线年龄为254±16Ma(2σ)。年龄误差稍大与该样品石榴子石中较低的Lu含量(1.1μg/g)和石榴子石-全岩的未充分分开的^(176)Lu/^(177)Hf比值(分别为0.05和0.01)有关。 展开更多
关键词 Lu-Hf年代学 榴辉岩 MC-ICP-MS
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CYP1A1 MspI多态性与子宫内膜癌易感性的病例对照研究 被引量:5
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作者 高静 项永兵 +4 位作者 徐望红 程家蓉 阮志贤 Shu Xiao-Ou 高玉堂 《肿瘤》 CAS CSCD 北大核心 2006年第8期790-791,共2页
自20世纪60年代以来,上海市区子宫内膜癌发病率逐年上升,且发病年龄有年轻化的趋势。子宫内膜癌的发病机制目前还不十分明确,多数流行病学研究显示子宫内膜癌的危险因素都与雌激素有关,雌激素水平升高导致的内膜增生及DNA损伤被认... 自20世纪60年代以来,上海市区子宫内膜癌发病率逐年上升,且发病年龄有年轻化的趋势。子宫内膜癌的发病机制目前还不十分明确,多数流行病学研究显示子宫内膜癌的危险因素都与雌激素有关,雌激素水平升高导致的内膜增生及DNA损伤被认为是子宫内膜癌发生的主要机制。 展开更多
关键词 子宫内膜样 流行病学 分子 多态现象 限制性片断长度 细胞色素P-450 CYP1A1 病例对照研究
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多元分析中的多重共线性及其处理方法 被引量:87
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作者 杨梅 肖静 蔡辉 《中国卫生统计》 CSCD 北大核心 2012年第4期620-624,共5页
在医学领域研究中,变量间存在多重共线性的现象十分普遍,其结果可能导致治疗效果或暴露因素作用的估计产生偏性。
关键词 多重共线性 多元分析 医学领域 暴露因素 治疗效果
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哺乳与子宫内膜癌关系的病例对照研究 被引量:4
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作者 徐望红 项永兵 +5 位作者 金凡 戴奇 阮志贤 程家蓉 舒晓鸥 高玉堂 《肿瘤》 CAS CSCD 北大核心 2004年第5期417-421,共5页
目的探讨哺乳对子宫内膜癌发生的影响.方法采用病例对照研究方法,对1997年1月~2001年12月确诊的30~69岁、有上海市区户口的832例子宫内膜癌病例与随机抽取的846例全人群对照进行生育及哺乳史的调查,取其中有活产史的病例754例和对照80... 目的探讨哺乳对子宫内膜癌发生的影响.方法采用病例对照研究方法,对1997年1月~2001年12月确诊的30~69岁、有上海市区户口的832例子宫内膜癌病例与随机抽取的846例全人群对照进行生育及哺乳史的调查,取其中有活产史的病例754例和对照805例,采用非条件logistic回归分析,调整可能的混杂因素,以评估哺乳对子宫内膜癌发生的比数比和95%可信区间.结果在有活产史的妇女中,哺乳者患子宫内膜癌的危险低于从未哺乳者,OR=0.76,95%CI:0.56~1.03.随着累积哺乳月数和每次活产平均哺乳月数的增加,发生子宫内膜癌的危险呈显著的下降趋势(趋势检验P值分别为0.05和<0.01).这种下降趋势亦见于末次哺乳年龄与子宫内膜癌的联系中,而且随着停止哺乳年数的增加,哺乳的保护作用下降.未见哺乳与活产次数的交互作用.结论哺乳,尤其是近期哺乳,有可能降低子宫内膜癌的发病危险. 展开更多
关键词 子宫内膜肿瘤 母乳喂养 病例对照研究
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汉、英工作记忆的加工和储存对中学生英语阅读理解的影响 被引量:13
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作者 孙聪颖 彭鹏 +1 位作者 陈海贤 陶沙 《心理发展与教育》 CSSCI 北大核心 2012年第1期61-69,共9页
本研究采用"视空间和言语交替"任务范式分离言语工作记忆的加工和储存两个成分,分别探讨了英语工作记忆的加工和储存成分对我国中学生英语阅读理解的作用及其途径,以及汉语工作记忆的加工和储存成分对中学生英语阅读理解是否... 本研究采用"视空间和言语交替"任务范式分离言语工作记忆的加工和储存两个成分,分别探讨了英语工作记忆的加工和储存成分对我国中学生英语阅读理解的作用及其途径,以及汉语工作记忆的加工和储存成分对中学生英语阅读理解是否具有跨语言影响。98名初中二年级学生完成了一般认知能力、英语阅读理解、汉语和英语工作记忆任务。结果表明:(1)英语工作记忆的加工和储存成分对英语阅读理解均有显著的独立预测作用;(2)英语工作记忆的储存成分对英语阅读理解的作用部分是由加工成分引起的;(3)汉语工作记忆的加工成分对英语阅读理解没有显著的直接预测作用,但却以英语工作记忆的加工成分为中介间接作用于英语阅读理解;汉语工作记忆的储存成分对英语阅读理解没有显著的预测作用。可见,言语工作记忆是一个多成分系统,加工和储存两个成分是相对分离的,并且它们具有不同的跨语言特性,加工存在跨语言一般性,而储存则具有语言特异性。 展开更多
关键词 汉语 英语 工作记忆 加工 储存 阅读理解
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小鼠SFRP-2基因的克隆及重组腺病毒制备 被引量:2
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作者 谭毅 谭冬梅 +2 位作者 何明忠 王立芝 后晓南 《肿瘤》 CAS CSCD 北大核心 2006年第2期135-138,共4页
目的构建小鼠secretedfrizzled-related protein-2(SFRP-2)全基因的重组腺病毒表达系统。方法采用基因工程技术,将SFRP-2基因片段克隆入穿梭质粒pAdTrack-CMV,然后在细菌内与pAdEasy-1进行同源重组,经脂质体转染293细胞包装并扩增腺病... 目的构建小鼠secretedfrizzled-related protein-2(SFRP-2)全基因的重组腺病毒表达系统。方法采用基因工程技术,将SFRP-2基因片段克隆入穿梭质粒pAdTrack-CMV,然后在细菌内与pAdEasy-1进行同源重组,经脂质体转染293细胞包装并扩增腺病毒颗粒。体外原代培养小鼠子宫内膜基质细胞,转染制备的腺病毒颗粒,并用Western blot法检测SFRP-2蛋白的表达。结果构建的小鼠SFRP-2重组腺病毒载体的效价达到5.6×1012pfu/mL,转染原代培养的小鼠子宫内膜基质细胞48h后,有SFRP-2蛋白的明显表达。结论成功构建含小鼠SFRP-2全基因的重组腺病毒载体。 展开更多
关键词 基因 SFRP-2 腺病毒属 遗传载体/生物合成 转染 间质细胞 细胞 培养的
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基于虚拟开车环境的自闭症儿童脑电样本熵 被引量:3
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作者 雷敏 孟光 +1 位作者 张文明 Nilanjan Sarkar 《物理学报》 SCIE EI CAS CSCD 北大核心 2016年第10期330-341,共12页
自闭症谱系障碍是一种涉及感觉、情感、记忆、语言、智力、动作等认知功能和执行功能障碍的精神疾病.本文从神经工效学角度出发,用虚拟开车环境作为复杂多任务激励源将大脑系统与人体动作控制等有机地结合起来,通过对脑电信号的滑动平... 自闭症谱系障碍是一种涉及感觉、情感、记忆、语言、智力、动作等认知功能和执行功能障碍的精神疾病.本文从神经工效学角度出发,用虚拟开车环境作为复杂多任务激励源将大脑系统与人体动作控制等有机地结合起来,通过对脑电信号的滑动平均样本熵分析来探索自闭症儿童在虚拟开车环境中的脑活动特征.研究发现不论是休息状态还是开车状态,自闭症患者的滑动平均样本熵总体上低于健康者,尤其在前额叶、颞叶、顶叶和枕叶功能区,表明自闭症儿童的行为适应性较低.不过,自闭症患者的开车状态与健康受试者的休息状态比较接近,表明虚拟开车环境或许有助于自闭症患者的干预治疗.此外,自闭症患者在颞叶区呈现显著性右半球优势性.本研究为进一步深入开展自闭症疾病的机理研究及其诊断、评估和干预等研究提供一种新的研究思路. 展开更多
关键词 自闭症 虚拟开车 样本熵 脑电信号
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优化骶尾骨侧位数字化X线摄影的方法学研究 被引量:1
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作者 田岚 蒋震 +4 位作者 尤超尘 李勇 赵春阳 龚建平 沈钧康 《医疗卫生装备》 CAS 2016年第2期86-89,共4页
目的:评价曝光辐射剂量及图像后处理2种优化措施对骶尾骨侧位数字化X线摄影影像质量的影响。方法:利用等效体模和矩形波测试卡选取适用于临床优化的曝光条件。37例患者每例均先后使用该优化的曝光条件和设备默认的曝光条件,摄取骶尾骨... 目的:评价曝光辐射剂量及图像后处理2种优化措施对骶尾骨侧位数字化X线摄影影像质量的影响。方法:利用等效体模和矩形波测试卡选取适用于临床优化的曝光条件。37例患者每例均先后使用该优化的曝光条件和设备默认的曝光条件,摄取骶尾骨侧位的初级图像共74幅,比较2次曝光所测得的毫安秒值和剂量面积乘积的统计学差异。分别使用设备自带的图像后处理软件包中的默认参数与优化参数对所有初级图像进行后处理,得到最终图像共148幅。由2位高年资放射科医师参照欧共体标准对最终图像的影像质量进行主观评价。结果:优化曝光条件下测得的辐射剂量较默认曝光条件显著降低(P<0.01)。2种不同的曝光条件对最终图像的影像质量没有显著性影响(P=0.13),而2种不同的图像后处理参数则显著地影响了最终图像的影像质量(P<0.01)。结论:数字化骶尾骨侧位摄影检查中,可在一定范围内减低辐射剂量,同时依靠图像后处理软件的优化,同样能得到满足诊断要求的高质量图像。 展开更多
关键词 数字化X线摄影 骶尾骨 辐射剂量 图像后处理
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甲基汞对原代大鼠星形胶质细胞的毒性作用 被引量:9
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作者 陈茹 蔡激扬 《中国康复理论与实践》 CSCD 2008年第5期437-439,共3页
目的初步研究甲基汞对原代SD大鼠星形胶质细胞产生毒性的机制。方法用甲基汞作用于原代SD大鼠星形胶质细胞,用高效液相色谱检测细胞氧化还原水平,用Western-blot检测核因子E2相关因子2(Nrf2)蛋白表达水平。结果随着甲基汞浓度的增加,星... 目的初步研究甲基汞对原代SD大鼠星形胶质细胞产生毒性的机制。方法用甲基汞作用于原代SD大鼠星形胶质细胞,用高效液相色谱检测细胞氧化还原水平,用Western-blot检测核因子E2相关因子2(Nrf2)蛋白表达水平。结果随着甲基汞浓度的增加,星形胶质细胞的还原水平明显下降。在甲基汞浓度较小时,随着甲基汞浓度的增加,星形胶质细胞Nrf2表达水平呈增长趋势;在甲基汞浓度较大时,随着甲基汞浓度的增加,星形胶质细胞Nrf2表达水平呈减少趋势。结论甲基汞对原代SD大鼠星形胶质细胞的毒性作用可能通过改变还原型谷胱甘肽(GSH)和Nrf2的功能而实现。 展开更多
关键词 甲基汞 星形胶质细胞 毒性作用 核因子E2相关因子2(Nrf2)
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中美两家综合医院老年人心脏双腔起搏器安置资料比较 被引量:1
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作者 卢才义 David Zhao +4 位作者 王士雯 高磊 颜伟 黄亚 刘鹏 《中国心脏起搏与心电生理杂志》 2008年第6期501-503,共3页
目的比较中美两个医学中心老年患者安置永久性心脏双腔起搏器的资料。方法对两个医学中心的两组老年起搏器安置手术病例进行分析,比较下列指标:①心房和心室导线类型和入路,②心房和心室导线固定方法和位置,③皮肤切口和囊袋的制作和止... 目的比较中美两个医学中心老年患者安置永久性心脏双腔起搏器的资料。方法对两个医学中心的两组老年起搏器安置手术病例进行分析,比较下列指标:①心房和心室导线类型和入路,②心房和心室导线固定方法和位置,③皮肤切口和囊袋的制作和止血方式,④皮肤切口的缝合方式,⑤术后观察处理方式和时间,⑥围术期起搏器功能和并发症,⑦随访1个月起搏器功能和并发症。结果两个医学中心各入选30例老年连续病例,基本临床资料两组间无显著性差异(P>0.05),但VUMC组体重明显高于心研所组,以往接受冠状动脉搭桥和支架治疗的病例多于心研所组(P<0.05)。两组病例手术成功率均为100%,无死亡或严重并发症。心研所组采用被动固定导线、结扎压迫式止血、切口拆线式缝合。VUMC组采用主动固定导线、囊袋和切口电凝止血和抗生素液冲洗、非拆线式皮内缝合技术,其在囊袋并发症、住院时间和围术期适应性方面明显优于心研所组。结论对老年患者安置心脏永久起搏器时,采用主动固定导线、对囊袋和切口电凝止血和冲洗、对切口作非拆线式皮内缝合可以避免术后长时间卧床、明显缩短住院时间、减少围术期并发症、改善患者对围术期和起搏系统的适应性。 展开更多
关键词 心血管病学 老年人 起搏器 电极导线
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大别榴辉岩Lu-Hf年代学研究
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作者 袁洪林 高山 +4 位作者 罗彦 宗春蕾 戴梦宁 柳小明 第五春荣 《矿物岩石地球化学通报》 CAS CSCD 2007年第z1期71-,共1页
  本文利用多接收电感耦合等离子体质谱仪(MC-ICP-MS)进行了同位素稀释法Lu-Hf年代学研究,建立了全岩Lu、Hf的分离条件.……
关键词 Lu-Hf年代学 榴辉岩 MC-ICP-MS
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