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基于紫甘蓝色素的智能凝胶材料及其甲醛变色研究
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作者 白剑芸 贲倩岑 +2 位作者 田晶 潘浩 孟庆华 《日用化学工业(中英文)》 CAS 北大核心 2024年第2期196-200,共5页
通过溶剂提取紫甘蓝中的花青苷色素(CabAn),在该色素化学结构的基础上,利用其质子化互变异构形成pH响应变色的特点,设计其与羟胺盐组合为超分子探针,通过甲醛与羟胺盐反应释放质子,而该质子则与花青苷的青绿色醌式体结合转化为紫红色吡... 通过溶剂提取紫甘蓝中的花青苷色素(CabAn),在该色素化学结构的基础上,利用其质子化互变异构形成pH响应变色的特点,设计其与羟胺盐组合为超分子探针,通过甲醛与羟胺盐反应释放质子,而该质子则与花青苷的青绿色醌式体结合转化为紫红色吡喃鎓式,从而实现甲醛变色功能,并将超分子探针溶于琼脂制备成智能凝胶(CabAn_HA@Agar),按照国际照明委员会基于CIELab颜色空间定义色差的方法来测量计算甲醛浓度。 展开更多
关键词 紫甘蓝 智能凝胶 甲醛 超分子探针
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Cancer incidence in Beijing, 2014 被引量:11
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作者 Shuo Liu Lei Yang +5 位作者 Yannan Yuan Huichao Li jing tian Sijia Lu Ning Wang Jiafu Ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2018年第1期13-20,共8页
Objective: To analyze cancer incidence data in Beijing in 2014 and temporal trends for selected common cancers during 2005 and 2014.Methods: A total of 144 secondary and tertiary hospitals reported newly diagnosed can... Objective: To analyze cancer incidence data in Beijing in 2014 and temporal trends for selected common cancers during 2005 and 2014.Methods: A total of 144 secondary and tertiary hospitals reported newly diagnosed cancer cases to Beijing Cancer Registry, which covers 13 million residents in Beijing. The cancer incidence rate was calculated in strata by cancer type, sex, age group and area. The population composition of China in 1982 and Segi's population structure were used to calculate age-standardized rates. Extensive procedures were used to assure the quality of the data.Results: The overall data quality indicators of the percentage of morphology verification(MV)(%), the percentage of death certificate-only(DCO)(%) and the mortality to incidence ratio(M/I) were 72.15%, 0.94% and0.54 respectively. A total of 45,300 new cancer cases were diagnosed in Beijing in 2014. The incidence rate was341.92/100,000(343.50/100,000 in males, 340.33/100,000 in females), and the age-standardized incidence rates by Chinese standard population(ASIRC) and by world standard population(ASIRW) were 143.48/100,000 and182.99/100,000, respectively. The cumulative incidence rate for cancer before 75 years was 20.61%. Cancers of lung, colorectum, liver, stomach and prostate were the top five common cancer types for males, while cancers of breast, lung, thyroid, colorectum and uterus were the top five common cancer types for females. The different patterns were also observed between rural and urban areas. Regarding temporal trends, the incidence of thyroid cancer has the fastest growth between 2005 and 2014. The incidence of liver cancer decreased, and stomach and esophageal cancer also decreased significantly for males in the last decade. Incidence rate for lung cancer was relatively stable during that period of time.Conclusions: With more than 45,000 new cases in Beijing in 2014, cancer remains an important public health problem. Actions should be taken to diminish total cancer incidence in Beijing. 展开更多
关键词 癌症 北京 人口结构 中国标准 发生率 年龄组 世界标准 相对稳定
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Secular trends in incidence of lung cancer by histological type in Beijing, China, 2000-2016 被引量:6
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作者 Lei Yang Ning Wang +5 位作者 Yannan Yuan Shuo Liu Huichao Li jing tian Jiafu Ji Aiguo Ren 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第2期306-315,共10页
Objective: The objective of this study was to characterize secular trends in the sex-specific, age-standardized incidence of lung cancer by histological type in Beijing, China, from 2000 to 2016 based on data from a p... Objective: The objective of this study was to characterize secular trends in the sex-specific, age-standardized incidence of lung cancer by histological type in Beijing, China, from 2000 to 2016 based on data from a populationbased cancer registry.Methods: Data on the incidence of cancer from 2000 to 2016 were obtained from the Beijing Cancer Registry.We examined trends in the sex-specific, age-standardized incidence of lung cancer by histological type using a Joinpoint regression model.Results: A total of 117,409 cases of lung cancer were diagnosed from 2000 to 2016. Overall, 73,062(62.23%)patients were males. The most common histological type among both sexes was adenocarcinoma; however, the proportion of adenocarcinoma differed significantly between males and females(45.36% vs. 77.14%, respectively,P<0.0001). The age-standardized incidence of total lung cancer increased from 2000 to 2010 with an annual percent change(APC) of 2.2% [95% confidence interval(95% CI), 1.5% to 2.9%] and stabilized thereafter. Among males, the incidence of total lung cancer peaked in 2008 and then decreased slightly, with an APC of-1.1%(95%CI,-2.1% to-0.1%). Among females, the incidence increased continuously during the study period, with an APC of 1.4%(95% CI, 0.9% to 1.9%). The incidence of squamous cell carcinoma decreased significantly in recent years among both sexes, with APCs of-2.6%(95% CI,-4.5% to-0.6%) from 2007 to 2016 for males and-5.4%(95%CI,-7.2% to-3.6%) from 2004 to 2016 for females. In contrast, the incidence of adenocarcinoma increased continuously throughout the study period, by APCs of 4.0%(95% CI, 2.6% to 5.4%) for males and 6.2%(95% CI,4.8% to 7.6%) for females. The incidence of small cell carcinoma peaked in 2007 and stabilized thereafter among males, whereas it peaked in 2012 and then decreased with an APC of-14.7%(95% CI,-25.3% to-2.6%) among females. The incidence of large cell carcinoma and other specified malignant neoplasm did not change much,whereas the incidence of unspecified type decreased among both sexes during the study period.Conclusions: Although the incidence of squamous cell carcinoma decreased significantly among both sexes in recent years in Beijing, China, adenocarcinoma increased continuously throughout the study period among both sexes. Knowledge of differences in trends is useful for surveillance and control of lung cancer. However, the reason for the increase in adenocarcinoma remains unclear and warrants investigation. 展开更多
关键词 Lung CANCER SECULAR TRENDS INCIDENCE BEIJING CANCER registration
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TiB、TiC和Y_(2)O_(3)增强钛基复合材料的蠕变行为和组织演变 被引量:1
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作者 徐丽娟 郑云飞 +5 位作者 梁振泉 韩世维 薛祥 肖树龙 田竟 陈玉勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第2期467-480,共14页
采用感应熔炼法制备(TiB+TiC)和(TiB+TiC+Y_(2)O_(3))增强钛基复合材料。蠕变试验在650℃和120~160 MPa下进行,通过XRD、SEM和TEM对铸态试样和蠕变试样的显微组织演变进行详细表征。结果表明,两种复合材料的铸态组织均为网篮组织。在相... 采用感应熔炼法制备(TiB+TiC)和(TiB+TiC+Y_(2)O_(3))增强钛基复合材料。蠕变试验在650℃和120~160 MPa下进行,通过XRD、SEM和TEM对铸态试样和蠕变试样的显微组织演变进行详细表征。结果表明,两种复合材料的铸态组织均为网篮组织。在相同的蠕变条件下,添加Y_(2)O_(3)的复合材料具有更低的稳态蠕变速率。蠕变后,在α/β界面、溶解的β相和增强体周围有硅化物析出,这些硅化物对位错有很强的钉扎作用。因为存在贯穿TiB晶须的层错结构,所以TiB周围的硅化物尺寸明显大于TiC和Y_(2)O_(3)周围的硅化物尺寸。蠕变变形主要受溶质阻力控制,位错运动还受到α/β界面、增强相和硅化物的影响。 展开更多
关键词 钛基复合材料 显微组织 蠕变行为 硅化物
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生土基梯度复合墙体材料热湿综合性能影响因素研究 被引量:1
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作者 芦白茹 张坤 +2 位作者 兰官奇 荆天 张玉婷 《粘接》 CAS 2023年第10期70-73,共4页
以黄土为基料,将水泥与粉煤灰作为凝胶材料制作试样,研究影响生土基梯度复合墙体材料热湿综合性能的各种因素,计算生土基梯度复合墙体材料的导热系数、含湿量以及热湿性能,并将导热系数与含湿量进行归一化处理,实现热湿综合性能的计算,... 以黄土为基料,将水泥与粉煤灰作为凝胶材料制作试样,研究影响生土基梯度复合墙体材料热湿综合性能的各种因素,计算生土基梯度复合墙体材料的导热系数、含湿量以及热湿性能,并将导热系数与含湿量进行归一化处理,实现热湿综合性能的计算,根据计算结果分析生土基梯度复合墙体材料热湿综合性能影响因素。实验结果表明,粉煤灰掺量、含水率、水泥掺量会影响生土基梯度复合墙体材料的热湿综合性能,试验获得生土基梯度复合墙体材料的最优配比为水泥掺量为4%、粉煤灰掺量为15%、含水量为16%。 展开更多
关键词 生土基梯度复合墙体材料 热湿综合性能 粉煤灰 含水量 导热系数 含湿量
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Serum metabolic profile and metabolome genome‑wide association study in chicken
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作者 jing tian Xiaoning Zhu +2 位作者 Hanyu Wu Yuzhe Wang Xiaoxiang Hu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期1926-1940,共15页
Background Chickens provide globally important livestock products.Understanding the genetic and molecular mechanisms underpinning chicken economic traits is crucial for improving their selective breeding.Influenced by... Background Chickens provide globally important livestock products.Understanding the genetic and molecular mechanisms underpinning chicken economic traits is crucial for improving their selective breeding.Influenced by a combination of genetic and environmental factors,metabolites are the ultimate expression of physiological processes and can provide key insights into livestock economic traits.However,the serum metabolite profile and genetic archi-tecture of the metabolome in chickens have not been well studied.Results Here,comprehensive metabolome detection was performed using non-targeted LC–MS/MS on serum from a chicken advanced intercross line(AIL).In total,7,191 metabolites were used to construct a chicken serum metabo-lomics dataset and to comprehensively characterize the serum metabolism of the chicken AIL population.Regula-tory loci affecting metabolites were identified in a metabolome genome-wide association study(mGWAS).There were 10,061 significant SNPs associated with 253 metabolites that were widely distributed across the entire chicken genome.Many functional genes affect metabolite synthesis,metabolism,and regulation.We highlight the key roles of TDH and AASS in amino acids,and ABCB1 and CD36 in lipids.Conclusions We constructed a chicken serum metabolite dataset containing 7,191 metabolites to provide a refer-ence for future chicken metabolome characterization work.Meanwhile,we used mGWAS to analyze the genetic basis of chicken metabolic traits and metabolites and to improve chicken breeding. 展开更多
关键词 CHICKEN Metabolic traits mGWAS SERUM
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Forward stagewise regression with multilevel memristor for sparse coding
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作者 Chenxu Wu Yibai Xue +6 位作者 Han Bao Ling Yang Jiancong Li jing tian Shengguang Ren Yi Li Xiangshui Miao 《Journal of Semiconductors》 EI CAS CSCD 2023年第10期105-113,共9页
Sparse coding is a prevalent method for image inpainting and feature extraction,which can repair corrupted images or improve data processing efficiency,and has numerous applications in computer vision and signal proce... Sparse coding is a prevalent method for image inpainting and feature extraction,which can repair corrupted images or improve data processing efficiency,and has numerous applications in computer vision and signal processing.Recently,sev-eral memristor-based in-memory computing systems have been proposed to enhance the efficiency of sparse coding remark-ably.However,the variations and low precision of the devices will deteriorate the dictionary,causing inevitable degradation in the accuracy and reliability of the application.In this work,a digital-analog hybrid memristive sparse coding system is pro-posed utilizing a multilevel Pt/Al_(2)O_(3)/AlO_(x)/W memristor,which employs the forward stagewise regression algorithm:The approxi-mate cosine distance calculation is conducted in the analog part to speed up the computation,followed by high-precision coeffi-cient updates performed in the digital portion.We determine that four states of the aforementioned memristor are sufficient for the processing of natural images.Furthermore,through dynamic adjustment of the mapping ratio,the precision require-ment for the digit-to-analog converters can be reduced to 4 bits.Compared to the previous system,our system achieves higher image reconstruction quality of the 38 dB peak-signal-to-noise ratio.Moreover,in the context of image inpainting,images containing 50%missing pixels can be restored with a reconstruction error of 0.0424 root-mean-squared error. 展开更多
关键词 forward stagewise regression in-memory computing MEMRISTOR sparse coding
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Shaped beam pattern synthesis with desired nulling level and minimum sidelobe level
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作者 Li-Ming Xu Qiang-Jian Song +3 位作者 Shi-Wen Lei Bo Chen jing tian Hao-Quan Hu 《Journal of Electronic Science and Technology》 CAS CSCD 2023年第1期35-45,共11页
For the anti-interference/denoise purpose,it usually requires minimizing the sidelobe level(SLL)of a wide-beam pattern with a desired low nulling level(NL)in the nulling region.To realize such an objective,the shaped-... For the anti-interference/denoise purpose,it usually requires minimizing the sidelobe level(SLL)of a wide-beam pattern with a desired low nulling level(NL)in the nulling region.To realize such an objective,the shaped-beam pattern synthesis(SBPS)is the most commonly used approach.However,since the SBPS problem focuses on synthesizing a predetermined beam shape,the minimum SLL via this approach cannot ensure to obtain the maximum power gain.Conversely,it cannot obtain the lowest SLL with a certain power gain requirement.Based on such consideration,this paper tries to further minimize SLL of a wide-beam pattern with a desired low NL nulling region,by solving the power gain pattern synthesis(PGPS)problem.The PGPS problem selects the array excitation by directly optimizing the power gain.Hence,it has the potential to reduce SLL,when achieving the equal mainlobe power gain constraint via SBPS.An iterative algorithm which converts the primal optimization problem into convex sub-problems is proposed,resulting in an effective problem-solving scheme.Numerical simulations demonstrate the proposed algorithm can obtain about 10-dB lower SLL than the existing algorithms. 展开更多
关键词 Array synthesis Minimum sidelobe level(SLL) Nulling level(NL) Pattern synthesis Wide-beam
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Wind-Thermal Environmental Characteristic of Multi-Variable Passive Enhanced Natural Ventilation System for High and Large Space Building
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作者 Lin Liu Haoran Huang +2 位作者 Chenghe Wu Liru Liu jing tian 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第5期34-51,共18页
Natural ventilation effects in high and large space buildings of tropical areas greatlya ffect the air conditioning energy consumption.Aiming at nearly zero energy building design,thisp aper mainly contributes to prov... Natural ventilation effects in high and large space buildings of tropical areas greatlya ffect the air conditioning energy consumption.Aiming at nearly zero energy building design,thisp aper mainly contributes to provide theoretical basis and reference for thermal comfortable air conditioning system design of high and large space buildings.Taking a theatre in Hainan as study object,a newly composite enhanced natural ventilation system is proposed by integrating theu nderground tunnel-based earth to air heat exchange system and the solar chimney.Ventilationq uantity,air velocity and air temperature field,human vertical temperature gradient differenceu nder24simulation working conditions are considered and analyzed by using ANSYS Fluent.Fort he underground tunnel,results show that Group Two with double underground tunnels and side airs upply location shows its advantages in cooling effects and air supply uniformity.Then for the solar chimney,results show that the solar radiation intensity contributes to larger difference int ransmission power and leads to different cooling effects.On the whole,the system under workingc ondition No.7with120m long,side air supply,double underground tunnel and20m high,1mw ide,0.6°absorber plate angle solar chimney shows its priority in better comprehensive performance. 展开更多
关键词 natural ventilation solar chimney earth to air heat exchange system energyc onservation thermal environment
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Endoscopic Ruler for varix size measurement:A multicenter pilot study
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作者 Yi-Fei Huang Sheng-Juan Hu +29 位作者 Yang Bu Yi-Ling Li Yan-Hong Deng Jian-Ping Hu Shao-Qi Yang Qian Shen Mark McAlindon Rui-Chun Shi Xiao-Qin Li Tie-Ying Song Hai-Long Qi Tai-Wei Jiao Meng-Yuan Liu Fang He Jun Zhu Bin Ma Xiao-Bin Yu Jian-Yang Guo Yue-Hua Yu Hai-Jiang Yong Wen-Tun Yao Ting Ye Hua Wang Wen-Fu Dong Jian-Guo Liu Qiang Wei jing tian Xiao-Guo Li Xavier Dray Xiao-Long Qi 《World Journal of Gastrointestinal Endoscopy》 2023年第9期564-573,共10页
BACKGROUND We invented Endoscopic Ruler,a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension.AIM To assess the feasibility and safety of Endoscopic Ruler,and evalua... BACKGROUND We invented Endoscopic Ruler,a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension.AIM To assess the feasibility and safety of Endoscopic Ruler,and evaluate the agreement on identifying large oesophageal varices(OV)between Endoscopic Ruler and the endoscopists,as well as the interobserver agreement on diagnosing large OV using Endoscopic Ruler.METHODS We prospectively and consecutively enrolled patients with cirrhosis from 11 hospitals,all of whom got esophagogastroduodenoscopy(EGD)with Endoscopic Ruler.The primary study outcome was a successful measurement of the size of varices using Endoscopic Ruler.The secondary outcomes included adverse events,operation time,the agreement of identifying large OV between the objective measurement of Endoscopic Ruler and the empirical reading of endoscopists,together with the interobserver agreement on diagnosing large OV by Endoscopic Ruler.RESULTS From November 2020 to April 2022,a total of 120 eligible patients with cirrhosis were recruited and all of them underwent EGD examinations with Endoscopic Ruler successfully without any adverse event.The median operation time of Endoscopic Ruler was 3.00 min[interquartile range(IQR):3.00 min].The kappa value between Endoscopic Ruler and the endoscopists while detecting large OV was 0.52,demonstrating a moderate agreement.The kappa value for diagnosing large OV using Endoscopic Ruler among the six independent observers was 0.77,demonstrating a substantial agreement.CONCLUSION The data demonstrates that Endoscopic Ruler is feasible and safe for measuring the size of varices in patients with cirrhosis and portal hypertension.Endoscopic Ruler is potential to promote the clinical practice of the two-grade classification system of OV. 展开更多
关键词 Oesophageal varices CIRRHOSIS Portal hypertension ESOPHAGOGASTRODUODENOSCOPY Endoscopic ruler
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洗梗时间及贮梗时间对微波膨胀烟梗吸湿性的影响 被引量:3
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作者 李晓 赵子龙 +4 位作者 景天 姚二民 陈瑞倩 袁帅 晋照普 《西南农业学报》 CSCD 北大核心 2019年第1期195-201,共7页
【目的】研究不同地区微波膨胀烟梗的吸湿性能,旨在控制微波膨胀烟梗加工含水率的稳定性及加工参数设置提供理论参考。【方法】实验室模拟制梗丝线加工过程,设置洗梗水温为70℃的条件下,采用单因素实验方法,研究了洗梗时间和贮梗时间对... 【目的】研究不同地区微波膨胀烟梗的吸湿性能,旨在控制微波膨胀烟梗加工含水率的稳定性及加工参数设置提供理论参考。【方法】实验室模拟制梗丝线加工过程,设置洗梗水温为70℃的条件下,采用单因素实验方法,研究了洗梗时间和贮梗时间对不同地区微波膨胀烟梗含水率增量和回透率的影响,并对实验结果进行方差分析及多重对比分析。【结果】①随洗梗时间的增加,微波膨胀烟梗含水率增量及回透率呈上升趋势。洗梗时间30 s时,试验区微波膨胀烟梗含水率达30%以上、回透率达99%以上。随贮梗时间的增加,微波膨胀烟梗含水率及其增量呈现下降趋势,而回透率呈现升高的趋势。贮梗时间3 h时,试验区微波膨胀烟梗含水率及回透率满足要求。②洗梗时间、地区及两者的交互作用对微波膨胀烟梗贮后含水率增量的影响均达到极显著水平。贮梗时间、地区及两者的交互作用对微波膨胀烟梗贮后含水率增量的影响均达到极显著水平。③在相同预处理参数下进行加工,试验区微波膨胀烟梗含水率之间存在极显著差异。由多重比较可知,云南地区及河南地区微波膨胀烟梗需分别单独进行预处理,而四川、江西、贵州3地区微波膨胀烟梗可在相同预处理参数下进行加工。【结论】在洗梗水温70℃,洗梗时间30 s、贮梗时间3 h的条件下,各地区微波膨胀烟梗含水率达30%以上,回透率达99%以上且含水率标偏均在0. 3%以下,均已满足烟梗预处理加工参数要求。 展开更多
关键词 洗梗时间 贮梗时间 微波膨胀烟梗 含水率 回透率
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能源互联网建设背景下供电企业OKR绩效管理模式研究
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作者 颜秉宇 景天 《河南财政税务高等专科学校学报》 2023年第1期35-39,共5页
随着能源互联网的迅速发展和供电企业战略目标的更新,传统的KPI绩效管理方式由于存在指标不全面、绩效评价与公司发展不协调、不能满足管理创新需要等问题,已经难以适应快速变化的外部环境,不再适用于供电公司。基于OKR的供电公司新型... 随着能源互联网的迅速发展和供电企业战略目标的更新,传统的KPI绩效管理方式由于存在指标不全面、绩效评价与公司发展不协调、不能满足管理创新需要等问题,已经难以适应快速变化的外部环境,不再适用于供电公司。基于OKR的供电公司新型绩效管理设计方案,需要从准备、设计、落地3方面展开,同时在公司战略、制度创新、组织创新和人力资源管理4方面进行完善,以保障其顺利实施。 展开更多
关键词 能源互联网 国家电网 绩效管理 关键成果目标法
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羊口疮病毒在羔羊4种原代细胞中的增殖特性研究 被引量:2
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作者 常建军 陈曦 +8 位作者 王天星 景添 李瑞蕊 郭含薇 刘启龙 王勇 李莉 陈德坤 文英 《动物医学进展》 北大核心 2021年第1期63-68,共6页
为了解羊口疮病毒(ORFV)感染羔羊不同组织细胞的偏好性,分别体外培养肾外膜上皮细胞、口唇表皮细胞、肺上皮细胞和睾丸原代细胞,接种ORFV FX株病毒液,记录接种12、24、36、72 h时细胞病变特征,并根据Reed-Muench方法计算TCID50。结果显... 为了解羊口疮病毒(ORFV)感染羔羊不同组织细胞的偏好性,分别体外培养肾外膜上皮细胞、口唇表皮细胞、肺上皮细胞和睾丸原代细胞,接种ORFV FX株病毒液,记录接种12、24、36、72 h时细胞病变特征,并根据Reed-Muench方法计算TCID50。结果显示,4种细胞均在不同时间点出现细胞变圆、出现空泡和细胞核凝集成团等特征性病变,其对应的TCID50分别为10^-6.22、10^-7.16、10^-5.9和10^-7.31。说明肾外膜上皮细胞等4种原代细胞均为ORFV的靶细胞。 展开更多
关键词 羊口疮病毒 体外培养 增殖特性 致病变特性
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膨胀烟梗体积测量系统的设计研究及验证
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作者 李晓 陈瑞倩 +5 位作者 王宇 赵子龙 何超 赵凯歌 景天 晋照普 《西南农业学报》 CSCD 北大核心 2019年第6期1391-1396,共6页
【目的】为提升膨胀烟梗体积的测量精度及稳定性,基于等温过程中的气体状态方程设计了一套膨胀烟梗体积测量系统,该系统主要由校准装置和体积测定装置两部分组成,通过砝码重量产生的压强以及研究对象气体的体积变化对烟梗体积进行表征... 【目的】为提升膨胀烟梗体积的测量精度及稳定性,基于等温过程中的气体状态方程设计了一套膨胀烟梗体积测量系统,该系统主要由校准装置和体积测定装置两部分组成,通过砝码重量产生的压强以及研究对象气体的体积变化对烟梗体积进行表征。【方法】以膨胀烟梗和回潮后的膨胀烟梗为试验材料,利用线性回归分析的方法建立砝码重量与待测物体积之间的关系模型,并通过试验分别对系统的测量精度和稳定性进行验证。【结果】①砝码重量x与1/A-Vx(记Y=1/A-Vx,A为定值且等于2.955×10^-3,Vx为待测物体积)成线性关系,且所建线性回归模型为Y=171.750x-1116.991。②该装置对膨胀烟梗和回潮后膨胀烟梗进行体积测定的平均相对误差分别为2.631%和3.618%,重复性检测最大变异系数分别为0.662%和0.542%,可满足装置检测精度需求,且装置重复性较好。【结论】该装置为烟草行业膨胀烟梗体积测定提供了一种精确有效的方法。 展开更多
关键词 理想气体状态方程 膨胀烟梗 体积测定 装置设计
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糖尿病性白内障患者术后发生角膜水肿的预测模型 被引量:8
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作者 田靖 兰长骏 +1 位作者 廖萱 林佳 《国际眼科杂志》 CAS 北大核心 2020年第11期1876-1881,共6页
目的:探讨糖尿病性白内障患者术后发生角膜水肿的危险因素并构建预测模型。方法:选取2017-01/2019-12本院收治的糖尿病性白内障患者312例,均采取择期超声乳化白内障摘除联合人工晶状体(IOL)植入手术。根据术后1wk内是否出现角膜水肿分... 目的:探讨糖尿病性白内障患者术后发生角膜水肿的危险因素并构建预测模型。方法:选取2017-01/2019-12本院收治的糖尿病性白内障患者312例,均采取择期超声乳化白内障摘除联合人工晶状体(IOL)植入手术。根据术后1wk内是否出现角膜水肿分为角膜水肿组(n=62)和非角膜水肿组(n=250)。比较两组患者性别、年龄、吸烟史、饮酒史、糖尿病病程、高血压病史、青光眼病史、角膜营养不良、慢性葡萄膜炎、晶状体核硬度Emery分级、术前前房深度、术中超声能量和有效超声时间、IOL材料和植入位置、术后角膜内皮细胞数量。采用逐步Logistic回归分析确定糖尿病性白内障患者术后发生角膜水肿的危险因素,确定危险因素后构建危险评分体系,绘制ROC曲线分析危险评分模型对术后角膜水肿的预测价值。结果:纳入的312例糖尿病性白内障患者中62例(19.9%)发生术后角膜水肿。根据逐步Logistic回归分析,年龄>60岁(OR=2.657,95%CI:1.135~6.220)、糖尿病病程>10a(OR=6.932,95%CI:1.911~25.145)、高血压病史(OR=2.783,95%CI:1.037~14.510)、青光眼病史(OR=3.679,95%CI:1.128~11.999)、慢性葡萄膜炎(OR=2.601,95%CI:1.099~6.156)、晶状体核硬度Ⅳ~Ⅴ级(OR=8.658,95%CI:2.595~28.887)、术前浅前房(OR=3.431,95%CI:1.679~7.011)、术后角膜内皮细胞数量(OR=3.026,95%CI:1.137~8.053)是糖尿病性白内障患者术后发生角膜水肿的危险因素。根据上述危险因素构建危险评分体系,年龄>60岁、高血压病史、青光眼病史、慢性葡萄膜炎、术前浅前房、术后角膜内皮细胞丢失≥10%分别对应1分,糖尿病病程>10a和晶状体核硬度Ⅳ~Ⅴ级分别对应2分,总分0~10分。危险评分模型预测糖尿病性白内障患者术后角膜水肿的ROC曲线下面积为0.848(95%CI:0.772~0.934),以8.94分为最佳临界值,此时的敏感度和特异度分别为85.3%和80.2%。结论:年龄>60岁、糖尿病病程>10a、高血压病史、青光眼病史、慢性葡萄膜炎、晶状体核硬度Ⅳ~Ⅴ级、术前浅前房、术后角膜内皮细胞丢失是糖尿病性白内障患者术后发生角膜水肿的危险因素,根据上述危险因素构建的危险评分模型对术后角膜水肿有较好预测价值。 展开更多
关键词 糖尿病性白内障 超声乳化白内障摘除 预测模型 晶状体核硬度
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羊布鲁氏菌病及其国内外防控净化措施 被引量:12
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作者 景添 王天星 +5 位作者 陈曦 陈凤强 冯皓 李佳 马文涛 陈德坤 《动物医学进展》 北大核心 2022年第2期116-120,共5页
布鲁氏菌病(简称“布病”)是由布鲁氏菌引起的一种人兽共患传染病。在引起布病的所有布鲁氏菌中,对人和家畜威胁最大的是羊种布鲁氏菌。近年来我国针对布病防控颁布了《国家布鲁氏菌病防治计划(2016-2020年)》等相关文件,但布病尤其是... 布鲁氏菌病(简称“布病”)是由布鲁氏菌引起的一种人兽共患传染病。在引起布病的所有布鲁氏菌中,对人和家畜威胁最大的是羊种布鲁氏菌。近年来我国针对布病防控颁布了《国家布鲁氏菌病防治计划(2016-2020年)》等相关文件,但布病尤其是羊布病的发生率仍然处于上升趋势。论文主要介绍国内常用的羊布病的防控方法和策略,并结合国外成功根除布病的经验,分析讨论其存在的缺点和不足,以期为我国羊布病防控净化工作提供借鉴与参考。 展开更多
关键词 羊布鲁氏菌病 流行 控制 净化
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代谢组学技术发展及其在农业动植物研究中的应用 被引量:13
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作者 田菁 王宇哲 +3 位作者 闫世雄 孙帅 贾俊静 胡晓湘 《遗传》 CAS CSCD 北大核心 2020年第5期452-465,共14页
代谢组学是依赖灵敏、稳定的分析流程和数据库,利用色谱–质谱联用、核磁共振技术对生物体内以及生物样品所有的小分子代谢物进行鉴定和定量分析的学科,在医学、食品科学、畜牧学、植物学等领域得到广泛应用。代谢组学方法可将代谢物种... 代谢组学是依赖灵敏、稳定的分析流程和数据库,利用色谱–质谱联用、核磁共振技术对生物体内以及生物样品所有的小分子代谢物进行鉴定和定量分析的学科,在医学、食品科学、畜牧学、植物学等领域得到广泛应用。代谢组学方法可将代谢物种类和含量的变化与生物表型变化建立更直接的联系,因此代谢组学逐渐成为继基因组学、转录组学、蛋白组学后对复杂性状系统解析的新的研究手段。本文介绍了代谢组学常用分析策略、检测平台和常用数据库。在此基础上,综述了代谢组学在农业动物重要经济性状代谢分子鉴定、疾病诊断、肉品质及动物制品安全检测等领域取得的进展,并总结了利用代谢组学、转录组学和基因组学等多组学研究在动植物重要性状的发育、形成和解析等领域取得的最新成果。代谢组学与其他多组学方法整合分析,可以更全面地阐述各类复杂性状的遗传机制,有助于完善“突变–基因–表达–代谢–表型”的完整生物学过程,为复杂性状的机理解析提供新方法,为新型农业育种提供新思路。 展开更多
关键词 代谢组学 广泛靶向代谢组学 代谢组检测平台 农业动物 多组学联合分析
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一种新型亚稳β钛合的热变形行为及显微组织演变表征 被引量:3
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作者 陈兆琦 徐丽娟 +5 位作者 曹守臻 杨建凯 郑云飞 肖树龙 田竟 陈玉勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第5期1513-1529,共17页
通过热压缩实验研究Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe-0.1B-0.1C锻态合金在750~900℃温度范围和0.001~1 s^(-1)应变速率范围内的热变形特征。应力-应变曲线表明,流变应力随着温度的提高和应变速率的降低而降低。显微组织对热变形参数十分... 通过热压缩实验研究Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe-0.1B-0.1C锻态合金在750~900℃温度范围和0.001~1 s^(-1)应变速率范围内的热变形特征。应力-应变曲线表明,流变应力随着温度的提高和应变速率的降低而降低。显微组织对热变形参数十分敏感,当应变速率保持在0.001 s^(-1)不变,温度达到790℃或者温度保持在910℃不变,应变速率不高于0.1s^(-1)时合金显微组织中出现动态再结晶晶粒。计算出加工硬化率θ,并发现动态再结晶倾向于在较高温度和较低应变速率条件下发生。得到合金的本构方程和加工硬化图,平均热激活能为242.78 k J/mol,而且只有少量失稳区在热加工图中出现,说明合金具有良好的热加工性能。当应变速率为0.1s^(-1)时,应力-应变曲线呈现一种异常的形状,连续出现两个应力峰值,这一现象可以归因于连续动态再结晶和再结晶晶粒的转动所造成的硬化现象与动态软化机制的混合作用。 展开更多
关键词 亚稳Β钛合金 热变形行为 显微组织演变 异常流变行为
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PPAR γ基因多态性与新生儿肺炎易感性及血清炎症细胞因子的关系 被引量:9
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作者 田静 惠晓君 +2 位作者 张靖 任亚方 张朋 《中国现代医学杂志》 CAS 北大核心 2021年第3期31-35,共5页
目的研究血清过氧化物酶体增殖物激活受体γ(PPAR γ)基因多态性与新生儿肺炎易感性及血清炎症细胞因子的关系。方法选取2016年3月—2019年3月南阳市中心医院收治的感染性肺炎新生儿90例。根据病情将感染性肺炎新生儿分为轻症肺炎组52... 目的研究血清过氧化物酶体增殖物激活受体γ(PPAR γ)基因多态性与新生儿肺炎易感性及血清炎症细胞因子的关系。方法选取2016年3月—2019年3月南阳市中心医院收治的感染性肺炎新生儿90例。根据病情将感染性肺炎新生儿分为轻症肺炎组52例和重症肺炎组38例,另取同期在该院分娩的80例健康新生儿作为对照组。检测PPAR γ基因rs1801282位点多态性及血清炎症细胞因子白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、细胞间黏附分子-1(ICAM-1)的质量浓度。结果重症肺炎组和轻症肺炎组新生儿C/C基因型的比例、等位基因C的频率及血清IL-6、TNF-α、ICAM-1质量浓度均高于对照组(P<0.05),GC+GG基因型的比例、等位基因G的频率低于对照组(P<0.05);重症肺炎组新生儿CC基因型的比例、等位基因C的频率及血清IL-6、TNF-α、ICAM-1质量浓度高于轻症肺炎组(P<0.05),GC+GG基因型的比例、等位基因G的频率低于轻症肺炎组(P<0.05);肺炎组中PPAR γ基因rs1801282位点GC+GG基因型新生儿的血清IL-6、TNF-α、ICAM-1质量浓度均低于CC基因型新生儿(P<0.05)。结论 PPAR-γ基因rs1801282位点C向G突变能减少炎症细胞因子的释放,可能是新生儿细菌性肺炎的保护因素。 展开更多
关键词 肺炎 婴儿 新生 PPARΓ 基因多态性 炎症细胞因子
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新媒体背景下青少年媒介依赖关系透析
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作者 田甜 林岳新 《伤害医学(电子版)》 2017年第2期57-62,共6页
随着信息技术的发展,以网络技术、移动通讯技术等新技术为代表的新媒体已经渗在我们生活的方方面面,尤其对青少年产生了巨大的影响,在给他们的成长带来便利的同时,青少年对网络、手机和娱乐节目的过度依赖,也带来他们了许多负面的影响。
关键词 新媒体 青少年 依赖
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