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变任务混频寿命相关载荷累积量分布特性

航空动力学报 2014年第11期29卷 2722-2728页

作者：赵福星邱栋杨兴宇郑小梅北京航空工程技术研究中心北京100076 中国人民解放军空军装备部可靠性办公室北京100843

在基于固定任务混频的寿命相关载荷累积量分布特性研究成果的基础上,推导了变任务混频条件下的寿命相关载荷累积量分布特性,结果表明:变任务混频的载荷参数累加量分布函数也是趋于正态分布.并采用数值方法模拟实际飞行过程中变任务混频... 详细信息

在基于固定任务混频的寿命相关载荷累积量分布特性研究成果的基础上,推导了变任务混频条件下的寿命相关载荷累积量分布特性,结果表明:变任务混频的载荷参数累加量分布函数也是趋于正态分布.并采用数值方法模拟实际飞行过程中变任务混频条件下寿命相关载荷的累积过程,模拟结果和理论结果吻合良好,进一步验证了分析结果的正确性.该结果可用于变任务混频下的寿命可靠性预测.

关键词：航空发动机结构寿命载荷分布函数任务混频可靠性

Genotype-phenotype relationship in a large cohort of osteogenesis imperfecta patients with COL1A1 mutations revealed by a new scoring system

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Chinese Medical Journal 2019年第2期132卷 145-153页

作者： Lu-Jiao Li Fang Lyu Yu-Wen Song Ou Wang Yan Jiang Wei-bo Xia Xiao-Ping xing Mei Li Department of Endocrinology National Health Commission Key Laboratory of EndocrinologyPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Background:Osteogenesis imperfecta (OI), a heritable bone fragility disorder, is mainly caused by mutations in COL1A1 gene encoding α1 chain of type I *** study aimed to investigate the COL1A1 mutation spectrum and quantitatively assess the genotype-phenotype relationship in a large cohort of Chinese patients with ***:A total of 161 patients who were diagnosed as OI in Department of Endocrinology of Peking Union Medical College Hospital from January 2010 to December 2017 were included in the *** COL1A1 mutation spectrum was identified by next generation sequencing and confirmed by Sanger sequencing.A new clinical scoring system was developed to quantitatively assess the clinical severity of OI and the genotype-phenotype relationship was *** independent sample t-test, analysis of variance, Mann-Whitney U-test, Chi-squared test, Pearson correlation, and multiple linear regression were applied for statistical ***:Among 161 patients with OI, 32.9% missense mutations, 16.8% non-sense mutations, 24.2% splice-site mutations, 24.8% frameshift mutations, and 1.2% whole-gene deletions were identified, of which 38 variations were *** mutations led to 53 patients carrying qualitative defects and 67 patients carrying quantitative defects in type I *** to patients with quantitative mutations, patients with qualitative mutations had lower alkaline phosphatase level (296 [132, 346] U/L vs.218 [136, 284] U/L, P=0.009) and higher clinical score (12.2 ± 5.3 vs.7.4 ± 2.4, Pbone mineral density, higher fracture frequency, more bone deformity, vertebral compressive fractures, limited movement, and dentinogenesis imperfecta (DI).Patients would not present with DI if the glycine substitutions happened before the 79th amino acid in triple helix of α1 chains .Conclusions:This presented distinctive COL1A1 mutation spectrum in a large cohort of Chinese pa

关键词： Osteogenesis imperfecta COL1A1 Clinical scoring system Genotype Phenotype

Preliminary molecular analysis of bacterial composition in periapical lesions with primary endodontic infections of deciduous teeth

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Chinese Medical Journal 2013年第16期126卷 3112-3117页

作者： SHANG Jia-jian YANG Qiu-bo zhao Huan-ying CAI Shuang ZHOU Yan SUN Zheng Capital Medical University School of Stomatology Beijing 100050China Medical Experiment'and Test Center Capital Medical UniversityBeijing 100069 China

Background The bacterial composition of periapical lesions in deciduous teeth has not been well *** study was designed to explore the bacterial compositions,especially the dominant bacteria in periapical lesions using 16S rRNA *** Tissue samples were collected from 11 periapical lesions in deciduous teeth with primary endodontic *** was extracted from each sample and analyzed using 16S rRNA cloning and sequencing for the identification of *** All DNA samples were positive for 16S rRNA gene *** hundred and fifty-one phylotypes from 810 clones were identified to eight phyla,and each sample contained an average of 25.9 *** addition,59 phylotypes were detected in more than two samples,and Fusobacterium （F.） nucleatum （8/11）,Dialister （D.） invisus （8/11）,Campylobacter （C.） gracilis （7/11）,Escherichia （E.） coil DH1 （6/11）,Aggregatibacter （A.） segnis （6/11）,and Streptococcus （S.） mitis （6/11） were the most prevalent ***,45 as-yet-uncultivated phylotypes were also *** Chronic periapical lesions in deciduous teeth contained polymicrobial ***,***,***,*** DH1,***,and *** were the most prevalent species detected by 16S rRNA sequencing.

关键词： 16S rRNA sequencing bacteria deciduous teeth periapical lesions

Herb-drug enzyme-mediated interactions and the associated experimental methods： a review

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Journal of Traditional Chinese Medicine 2016年第3期36卷 392-408页

作者： Li bo zhao Baosheng Liu Yang Tang Mingmin Lǚe Beiran Luo Zhiqiang Zhai Huaqiang School of Chinese Materia Medica Beijing University of Chinese Medicine Beijing 100102 China Center of Scientific and Experiment Beijing niversity of Chinese Medicine Beijing 100029 China Beijing Key Laboratory of Protection and Utilization of Chinese Medicine Beijing Normal UniversityBeijing 100875 China

OBJECTIVE: To review the interactions between herbs and widely used drugs and summarize the associated experimental ***: Definite herb-drug interactions were obtained by searching Pub Med, other large overseas databases and summarizing new researches from China. We summarize some methods to assess the interaction between herbs and drugs involving microsomal, cell culture and animal experiments, and clinical trials, classifying this method as single ingredient herbs, crude herb extracts, andherbal ***: Many herbs interact with drugs through a complex cytochrome P450 and/or P-glycoprotein mechanism. Herb-induced enzyme inhibition and/or induction may result in enhanced and / or decreased plasma, tissue, urine and bile drug concentrations, leading to a change in a drug's pharmacokinetic parameters and resulting in the improper treatment of patients and potentially severe side effects. Use of an appropriate method for comprehensively assessing herb-drug interactions can minimize clinical risks. Different methods were used by researchers to assess the pharmacological changes of drugs in vivo and in vitro and the mechanisms of the interactions from microsomal, cell culture and animal experiments, and clinical trials are discussed in this ***: Co-medication with herbs can result in changes in pharmacological effects of many drugs. This review describes the assessment of single-ingredient herbs, crude herb extracts, and herbal formulae. When choosing a research method to investigate herb-drug interactions, the properties of the drugs and herbs should be considered.

关键词： Herb-drug interaction Metabolism Cytochrome P-450 enzyme system P-glycoprotein Review

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森林地表凋落物含水率红外光谱特性分析

光谱学与光谱分析 2018年第10期38卷 3101-3105页

作者：邢键叶颖慧马召彭博杨柳松宋文龙东北林业大学机电工程学院黑龙江哈尔滨150040

为了实现森林地表凋落物含水率的实时测量,研究了森林地表凋落物含水率与红外光谱特性参数之间的关系。选取了四种森林地表凋落物,搭建了含水率红外光谱测量装置,获得了不同含水率所对应的红外吸收光谱图,分析了不同含水率与峰值吸收光... 详细信息

为了实现森林地表凋落物含水率的实时测量,研究了森林地表凋落物含水率与红外光谱特性参数之间的关系。选取了四种森林地表凋落物,搭建了含水率红外光谱测量装置,获得了不同含水率所对应的红外吸收光谱图,分析了不同含水率与峰值吸收光强、谷肩连线与谷底连线交点纵坐标、吸收谷面积之间的关系。结果表明,含水率吸收谱线峰值在1 450nm附近;三种光谱参数中,森林地表凋落物含水率与峰值吸收光强线性相关性最好,所得一元回归方程经F检验显著性良好,斜率的相对不确定度均小于1.0%和截距的相对不确定度小于0.51%,相关系数γ>0.95。为含水率实时测量仪的光源选择和标定提供了依据。

关键词：含水率森林地表凋落物近红外光谱森林防火

Preparation of polypyrrole/Co_(x)Mo_(y)O_(z)composite and its microwave a bsorption performance

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分子科学学报 2024年第2期40卷 131-137页

作者： WANG bo CONG Jiyuan xing Shuangxi GUAN Hongtao Faculty of Chemistry Northeast Normal UniversityChangchun 130024China School of Materials and Energy Yunnan UniversityKunming 650091China

The present work combines polypyrrole with cobalt molybdenum oxide using an in situ surface growth method to adjust impedance matching and explore the microwave absorption performance of the composite *** complex dielectric constant and magnetic permeability of the samples are measured in the frequency range of 2 to 18 GHz using a vector network analyzer,and their reflection loss(RL)value is *** results show that the obtained PPy/Co_(x)Mo_(y)O_(z)composite exhibits excellent absorption performance at 17.68 GHz under a matching thickness of 2.0 mm,with an RL_(min)of-46.02 dB and an effective absorption bandwidth of 4.08 *** excellent absorption performance can be attributed to the combined effect of multion loss mechanisms,including conduction loss,interface polarization,dipole polarization and eddy current loss.

关键词： microwave absorption polypyrrole cobalt-molybdenum oxide

Acupuncture and/or moxibustion for the treatment of lumbar disc herniation:quality assessment of systematic reviews

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Traditional Medicine Research 2020年第4期5卷 282-294页

作者： Zi-Han Yin Chao-Xi Zhu Gui-xing Xu Cheng Ying Ai-Ling Huang Ya-Nan Fu Jiao Chen Ling zhao Fan-Rong Liang Chengdu University of Traditional Chinese Medicine Chengdu 610075China

Objective:In the current systematic review on acupuncture and/or moxibustion for lumbar disc herniation(LDH),we evaluated the methodology and quality of evidence and reports to provide necessary information for accurate clinical decision-making regarding acupuncture and/or moxibustion for ***:From databases such as CBM(Chinese biomedical literature database),VIP(China science and technology journal database),CNKI(China national knowledge infrastructure),WF(Wanfang database),Web of Science,Embase,Medline,and Cochrane Library,systematic reviews on acupuncture and/or moxibustion for LDH were retrieved,and the methodological quality of the literature was evaluated according to the assessment of multiple systematic reviews(AMSTAR)***,the grading of recommendations assessment,development and evaluation(GRADE)system was used to grade the quality of evidence and the preferred reporting items for systematic reviews and meta-analyses(PRISMA)statement to evaluate the quality of the ***:A total of 18 systematic reviews were included,and the conclusion is that acupuncture and/or moxibustion have some advantages in terms of efficacy and safety with regard to LDH *** to the AMSTAR score,there were 4 high-quality studies,13 moderate-quality studies,and 1 low-quality *** showed that quality of evidence such as total effective rate of LDH and VAS was low and that of other forms of evidence was *** PRISMA statement showed that 8 articles were in line with 20 or more of the 27 items,and 10 articles were in line with 10-19 of the 27 ***:At present,acupuncture and/or moxibustion for LDH has a good curative *** importantly,its methodological quality was of moderate level and the report quality was generally good and relatively ***,the poor quality of the original research results was reflected in the quality of *** studies are needed to make sure whether acupuncture is more effective

关键词： Lumbar disc herniation Acupuncture therapy Overview of systematic reviews AMSTAR GRADE PRISMA.

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基于复杂网络的城市交通堵塞载荷再分配控制

公路交通科技 2019年第5期36卷 98-103页

作者：王世波赵金楼郑继兴齐齐哈尔大学经济与管理学院黑龙江齐齐哈尔161006 哈尔滨工程大学经济管理学院黑龙江哈尔滨150001

近年来,城市交通堵塞是困扰城市经济发展建设的一个重要问题,给人们的生产、生活带来诸多不便,但由于城市规划、人口密度、交通设施等多种因素,交通堵塞的情况不可避免,应对交通堵塞,使堵塞的载荷合理分配,避免大规模级联堵塞现象发生... 详细信息

近年来,城市交通堵塞是困扰城市经济发展建设的一个重要问题,给人们的生产、生活带来诸多不便,但由于城市规划、人口密度、交通设施等多种因素,交通堵塞的情况不可避免,应对交通堵塞,使堵塞的载荷合理分配,避免大规模级联堵塞现象发生具有现实研究价值。针对城市交通网络堵塞问题,为交通网络中的每个节点设置了初始载荷。根据各个节点的载荷量是否超过其阈值判断节点是否失效,提出了一种失效节点载荷再分配的非线性模型,分析了该模型触发级联失效的条件。对齐齐哈尔市城市交通网络分别进行随机攻击和蓄意攻击,运用Matlab编程方法对堵塞节点引发的级联失效进行了仿真,选择更容易理解的网络抗击毁性测度方法判断了攻击对齐齐哈尔市交通网络的破坏性。结果表明:合理调节失效节点载荷的再分配策略能够有效提升网络抗击毁性,降低交通网络级联失效引发的失效节点数量,避免大规模级联失效现象发生;在容量系数较小时,蓄意攻击比随机攻击对网络的破坏性更强,但现实生活中由于种种条件限制,容量系数不可能过大。因此,需要适当调节交通堵塞载荷的分配系数,使得堵塞载荷合理分配,进而有效减少失效节点数量,避免城市交通大规模级联失效现象的发生。

关键词：城市交通载荷再分配仿真分析复杂网络级联失效

Inhibitory effect of antisense oligodeoxynucleotide to p44/p42 MAPK on angiotensin Ⅱ-induced hypertrophic response in cultured neonatal rat cardiac myocyte

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Acta Pharmacologica Sinica 2004年第1期 43-48页

作者： Shi-qin ZHANG, bo DING, zhao-gui GUO, Yun-xia LILaboratory of Molecular Pharmacology, Xiang Ya School of Medicine, Central South University, Changsha,, 410078,China

AIM: To explore the inhibitory effect of antisense oligonucleotide (ODN) to mitogen activated protein kinase (MAPK) on cardiomyocyte hypertrophy induced by angiotensin Ⅱ (Ang Ⅱ). METHODS: A 17-mer phosphorothioate protected antisense ODN directed against the initiation of translation sites of the p42 and p44 MAPK isoforms by liposomal transfection was applied to inhibit the translation of p44/p42 MAPK mRNA. The sense and random ODNs to p44/p42MAPK were used as sequence controls. Neonatal cardiac myocytes were exposed to Ang Ⅱ (10 nmol/L) for 5 min and then harvested in lysis buffer for the measurement of the activity and the phosphorylated protein content of p44/p42MAPK that were tested by P-81 phosphocellulose filter paper method and Western blotting, respectively. The

关键词： mitogen-activated protein kinases antisense oligodeoxynucleotides angiotensin Ⅱ hypertrophy myocardium