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Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu chen xue-Jun li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Bacterial Community Structure and Diversity in a Black Soil as Affected by Long-Term Fertilization

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Pedosphere 2008年第5期18卷 582-592页

作者： WEI Dan YANG Qian ZHANG Jun-Zheng WANG Shuang chen xue-li ZHANG Xi-lin li Wei-Qun Harbin Institute of Technology Harbin 150001 （China）. The Institute of Soil Fertility and Environmental Sources Heilongjiang Academy of Agricultural Sciences Harbin 150086（China）

Black soil （Mollisol） is one of the main soil types in northeastern China. Biolog and polymerase chain reactiondenaturing gradient gel electrophoresis （PCR-DGGE） methods were used to examine the influence of various fertilizer combinations on the structure and function of the bacterial community in a black soil collected from Harbin, Heilongjiang Province. Biolog results showed that substrate richness and catabolic diversity of the soil bacterial community were the greatest in the chemical fertilizer and chemical fertilizer＋manure treatments. The metabolic ability of the bacterial community in the manure treatment was similar to the control. DGGE fingerprinting indicated similarity in the distribution of most 16S rDNA bands among all treatments, suggesting that microorganisms with those bands were stable and not influenced by fertilization. However, chemical fertilizer increased the diversity of soil bacterial community. Principal com- ponent analysis of Biolog and DGGE data revealed that the structure and function of the bacterial community were similar in the control and manure treatments, suggesting that the application of manure increased the soil microbial population, but had no effect on the bacterial community structure. Catabolic function was similar in the chemical fertilizer and chemical fertilizer＋manure treatments, but the composition structure of the soil microbes differed between them. The use of chemical fertilizers could result in a decline in the catabolic activity of fast-growing or eutrophic bacteria.

关键词： bacteria community black soil chemical fertilizer diversity manure

Temporal and Spatial Dynamics of Bacterial Community in the Rhizosphere of Soybean Genotypes Grown in a Black Soil

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Pedosphere 2009年第6期19卷 808-816页

作者： JIN Jian WANG Guang-Hua liU Xiao-Bing liU Jii-Dong chen xue-li S. J. HERBERT Key Lab of Black Soil Ecology Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Harbin 150081 (China) Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 (USA)

The dynamics of rhizosphere microbial communities is important for plant health and productivity, and can be influenced by soil type, plant species or genotype, and plant growth stage. A pot experiment was carried out to examine the dynamics of microbial communities in the rhizosphere of two soybean genotypes grown in a black soil in Northeast China with a long history of soybean cultivation. The two soybean genotypes, Beifeng 11 and Hai 9731, differing in productivity were grown in a mixture of black soil and siliceous sand. The bacterial communities were compared at three zone locations including rhizoplane, rhizosphere, and bulk soil at the third node （V3）, early flowering （R1）, and early pod （R3） stages using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DCGE） of 16S rDNA. The results of principal component analyses （PCA） showed that the bacterial community structure changed with growth stage. Spatially, the bacterial communities in the rhizoplane and rhizosphere were significantly different from those in the bulk soil. Nevertheless, the bacterial communities in the rhizoplane were distinct from those in the rhizosphere at the V3 stage, while no obvious differences were found at the R1 and R3 stages. For the two genotypes, the bacterial community structure was similar at the V3 stage, but differed at the R1 and R3 stages. In other words, some bacterial populations became dominant and some others recessive at the two later stages, which contributed to the variation of the bacterial community between the two genotypes. These results suggest that soybean plants can modify the rhizosphere bacterial communities in the black soil, and there existed genotype-specific bacterial populations in the rhizospbere, which may be related to soybean productivity.

关键词： PCR-DGGE plant growth stage 16S rDNA soybean productivity

Untreated Prior Pulmonary Tuberculosis Adversely Affects Pregnancy Outcomes in Infertile Women Undergoing in vitro Fertilization and Embryo Transfer: A Large Retrospective Cohort Study

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Biomedical and Environmental Sciences 2021年第2期34卷 130-138页

作者： GAI Xiao Yan CHI Hong Bin ZENG lin CAO Wen li chen li xue ZHANG chen LU Ming NING Lan Ding CHANG Chun ZHANG Wei Xia liU Ping li Rong SUN Yong Chang QIAO Jie Department of Respiratory and Critical Care Medicine Peking University Third HospitalBeijing 100191China Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology Beijing 100191China Research Center of Clinical Epidemiology Peking University Third HospitalBeijing 100191China Tuberculosis Department Beijing Geriatric HospitalBeijing 102699China Information Center Peking University Third HospitalBeijing 100191China

Objective Prior pulmonary tuberculosis(PTB) on chest X-ray(CXR) was commonly found in infertile patients receiving examinations before in vitro fertilization and embryo transfer(IVF-ET). It was unclear whether untreated PTB would affect pregnancy outcomes after *** We conducted a retrospective cohort study of 14,254 infertile patients who had received IVFET at Peking University Third Hospital in 2017. Prior PTB was defined as the presence of signs suggestive of old or inactive PTB on CXR, with or without a clinical TB history. Patients who had prior PTB on CXR but had not received a clinical diagnosis and anti-TB therapy were included for analysis. live birth,clinical pregnancy, and miscarriage rates were compared between the untreated PTB and non-PTB *** The untreated PTB group had significantly lower clinical pregnancy(31.7% vs. 38.1%) and live birth(23.8% vs. 30.6%) rates than the non-PTB group(both P live birth rate [odds ratio(OR), 0.80;95% confidence interval(CI), 0.66–0.98;P = 0.028] in all patients and for increased miscarriage(OR, 4.19;95% CI,1.69–10.39;P = 0.002) and decreased live birth(OR, 0.45;95% CI, 0.24–0.83;P = 0.011) rates in patients with unexplained *** Untreated PTB was associated with adverse pregnancy outcomes after IVF-ET, especially in patients with unexplained infertility, highlighting the clinical significance of PTB in this specific patient population.

关键词： Tuberculosis Embryo transfer In vitro fertilization Infertility Pregnancy outcome

Bacterial Community Structure in a Mollisol Under Long-Term Natural Restoration, Cropping, and Bare Fallow History Estimated by PCR-DGGE

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Pedosphere 2009年第2期19卷 156-165页

作者： WANG Guang-Hua JIN Jian liU Jun-Jie chen xue-li liU Ju-Dong liU Xiao-Bing Key Laboratory of Black Soil Ecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China

Soil microbial biomass and community structures are commonly used as indicators for soil quality and fertility. A investigation was performed to study the effects of long-term natural restoration, cropping, and bare fallow managements on the soil microbial biomass and bacterial community structures in depths of 0-10, 20 30, and 40-50 cm in a black soil （Mollisol）. Microbial biomass was estimated from chloroform fumigation-extraction, and bacterial community structures were determined by analysis of 16S rDNA using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR- DGGE）. Experimental results showed that microbial biomass significantly declined with soil depth in the managements of restoration and cropping, but not in the bare fallow. DGGE profiles indicated that the band number in top 0-10 cm soils was less than that in depth of 20-30 or 40-50 cm. These suggested that the microbial population was high but the bacterial community structure was simple in the topsoil. Cluster and principle component analysis based on DGGE banding patterns showed that the bacterial community structure was affected by soil depth more primarily than by managements, and the succession of bacterial community as increase of soil depth has a similar tendency in the three managements. Fourteen predominating DGGE bands were excised and sequenced, in which 6 bands were identified as the taxa of Verrueomicrobia, 2 bands as Actinobacteria, 2 bands as α-Proteobacteria, and the other 4 bands as 8-Proteobacteria, Aeidobacteria, Nitrospira, and unclassified bacteria. In addition, the sequences of 11 DGGE bands were closely related to uncultured bacteria. Thus, the bacterial community structure in black soil was stable, and the predominating bacterial groups were uncultured.

关键词： bacterial community black soil denaturing gradient gel electrophoresis (DGGE) polymerase chain reaction (PCR) soil depth

648nm激光雪崩抽运掺Tm晶体的本征光学双稳特性研究

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物理学报 2008年第1期57卷 278-284页

作者：李立张新陆陈历学哈尔滨工业大学物理系哈尔滨150001 哈尔滨工程大学理学院哈尔滨150001

理论研究了648nm激光雪崩抽运掺Tm晶体的本征光学双稳态.根据系统的非线性速率方程理论,推导出了稳态近似下雪崩阈值的解析表达式,数值研究了光子雪崩动力学响应、本征光学双稳性以及系统参数对光学双稳态的影响等.研究结果表明,648nm... 详细信息

理论研究了648nm激光雪崩抽运掺Tm晶体的本征光学双稳态.根据系统的非线性速率方程理论,推导出了稳态近似下雪崩阈值的解析表达式,数值研究了光子雪崩动力学响应、本征光学双稳性以及系统参数对光学双稳态的影响等.研究结果表明,648nm激光抽运下可以观察到掺Tm激光晶体的2μm荧光辐射本征光学双稳态,通过改变可控的实验参数能够实现对光学双稳回线环的形状调节.

关键词：光学双稳动力学掺Tm晶体光子雪崩

Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu chen Jie li chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Characteristics associated with falls among the elderly within aged care wards in a tertiary hospital： a retrospective case-control study

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Chinese Medical Journal 2010年第13期123卷 1668-1672页

作者： chen xue-li liU Yun-hu Daniel KY Chan SHEN Qing Huong Van Nguyen Department of Rehabilitation Beijing Geriatric Hospital Beijing 100095 China Aged Care Bankstown-Lidcombe Hospital Sydney New South Wales Australia Faculty of Medicine University of New South Wales Sydney Anetralia

Background Falls are the most frequently reported adverse events in inpatient settings. We conducted a retrospective case-control study of inpatient falls within aged care wards in a tertiary hospital to investigate the associated characteristics of elderly patients suffering from falls and fall-related characteristics. Methods Consecutive retrospective cross-sectional design spanned July 2006 to December 2008. Patient group： Information on all aged care inpatients who suffered from 1 or more falls was extracted from Incident Information Management System （IIMS）. Further details about the particular admission（s） were obtained from patients＇ medical records, e.g., patients＇ characteristics and circumstances surrounding the falls. Randomly selected aged care patients who did not suffer from a fall and who were discharged from the hospital in the same period served control group. Characteristics among patients with single fall and recurrent falls, as well as non-railers were compared. Results Of the 438 falls evaluated, 71.9% occurred in patients＇ room and 18.9% in patients＇ bathroom/toilet. The common activities were moving/transferring and taking shower/toileting, respectively, 70.3%, 12.1% while occurring falls; and time of falls had a high peak during 9：00-11：00 a.m. Many were unassisted while falling. The common contributing factors for fall were intrinsic factors. Patients with recurrent falls were more likely to have lower Mini-Mental State Examination （MMSE） score. Logistic regression analysis showed length of stay longer than five weeks, dementia and stroke were independent risk factors for recurrent falls; and living in hostel/nursing home preadmission, needing assistance with mobility, cognitive impairment, stroke, incontinence and arthritis/osteoporosis were independent risk factors for fall. Conclusions In an aged care ward, falls are independently associated with recurrent factors. Cognitive impairment/dementia was a strong risk factor for falls, and main

关键词： falls recurrent falls inpatients the elderly

不同居民燃煤炉具大气污染物排放差异性及减排分析

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环境科学 2020年第10期41卷 4462-4469页

作者：张熠晨薛陈利刘杰钟连红薛亦峰首都师范大学资源环境与旅游学院北京100048 北京市环境保护科学研究院国家城市环境污染控制工程技术研究中心北京100037

为探究不同类型炉具的大气污染物排放差异,本研究选择5种常见的新式居民燃煤炉具(方型煤炉具、折流换热炉具、炕暖炊一体化炉具、气化正烧及气化反烧炉具)在实验室内进行模拟燃烧和大气污染物排放水平监测,定量评估不同炉具的环境效果,... 详细信息

为探究不同类型炉具的大气污染物排放差异,本研究选择5种常见的新式居民燃煤炉具(方型煤炉具、折流换热炉具、炕暖炊一体化炉具、气化正烧及气化反烧炉具)在实验室内进行模拟燃烧和大气污染物排放水平监测,定量评估不同炉具的环境效果,识别污染排放水平差异的影响因素及原因,从而提出炉具研发设计等污染减排的改进建议.结果表明:(1)不同炉具大气污染物排放差异较大,炕暖炊一体的炉具污染排放强度最大,3种大气污染物(SO2、NOx和颗粒物)的排放强度为2.9 kg·t-1,是平均值的1.6倍;应用方型煤技术的炉具大气污染物排放强度最低,是平均值的65%.(2)不同炉具在不同燃烧阶段其气态污染物排放也呈现出明显的差异和特征.旺火阶段方型煤炉具NOx排放浓度为0.49mg·m^-3,相较于其他类型炉具降低了45%~72%;气化反烧炉具的SO2排放浓度为1.38mg·m^-3,相较于其他类型炉具最高降低了28%.(3)影响炉具大气污染物排放因素包括应用技术及燃烧类型,采用方型煤及气化反烧技术的炉具环境效益较好,但两类炉具的经济成本分别达到2.0万元和1.8万元,明显高于其他类型炉具.(4)考虑不同炉具污染排放差异,建议采取差异化的经济政策和严格的排放和产品标准,推广使用节能环保型炉具,降低燃煤炉具大气污染物排放.

关键词：居民燃煤炉具大气污染排放浓度排放因子污染控制对策