检索结果-南通市图书馆

立体位阻效应导致的苯酚的区域选择性溴化（英文）

在线全文

学校读者我要写书评

暂无评论

有机化学 2019年第10期39卷 2796-2801页

作者：马献涛周坤洁任梦娟王梦雨于静信阳师范学院化学化工学院

报道了苯酚与廉价易得的氢溴酸的区域选择性溴化反应.研究发现使用含有较大取代基的亚砜取代广为使用的二甲亚砜作为氧化剂,可以极大地提高反应的区域选择性,以中等至优秀的收率、高达99/1的区域选择性得到预期的溴代苯酚产物.该方法可... 详细信息

报道了苯酚与廉价易得的氢溴酸的区域选择性溴化反应.研究发现使用含有较大取代基的亚砜取代广为使用的二甲亚砜作为氧化剂,可以极大地提高反应的区域选择性,以中等至优秀的收率、高达99/1的区域选择性得到预期的溴代苯酚产物.该方法可以很容易放大到50 mmol级别,并且通过萃取与重结晶分离技术即可得到预期的溴代苯酚产物.

关键词：苯酚区域选择性溴化氢溴酸亚砜位阻效应

Analysis of COVID-19 Guideline Quality and Change of Recommendations:A Systematic Review

在线全文

学校读者我要写书评

暂无评论

Health Data Science 2021年第1期2021卷 88-109页

作者： Siya Zhao Shuya Lu Shouyuan Wu Zijun Wang Qiangqiang Guo Qianling Shi Hairong Zhang Juanjuan Zhang Hui Liu Yunlan Liu Xianzhuo Zhang Ling Wang mengjuan ren Ping Wang Hui Lan Qi Zhou Yajia Sun Jin Cao Qinyuan Li Janne Estill Joseph LMathew Hyeong Sik Ahn Myeong Soo Lee Xiaohui Wang Chenyan Zhou Yaolong Chen School of Public Health Lanzhou UniversityLanzhouChina Institute of Health Data Science Lanzhou UniversityLanzhouChina Department of Pediatric Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduChina Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital ChengduChina Evidence-Based Medicine Center School of Basic Medical SciencesLanzhou UniversityLanzhouChina The First School of Clinical Medicine Lanzhou UniversityLanzhouChina National Clinical Research Center for Child Health and Disorders Ministry of Education Key Laboratory of Child Development and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren’s Hospital of Chongqing Medical UniversityChongqingChina Institute of Global Health University of GenevaGenevaSwitzerland Institute of Mathematical Statistics and Actuarial Science University of BernBernSwitzerland Advanced Pediatrics Centre PGIMER ChandigarhChandigarhIndia Department of Preventive Medicine Korea UniversitySeoulRepublic of Korea Korea Cochrane Centre SeoulRepublic of Korea Evidence Based Medicine SeoulRepublic of Korea Korea University School of Medicine SeoulRepublic of Korea Korea Institute of Oriental Medicine DaejeonRepublic of Korea University of Science and Technology DaejeonRepublic of Korea London Southbank University LondonUK Tianjin University of Traditional Chinese Medicine TianjinChina WHO Collaborating Centre for Guideline Implementation and Knowledge Translation LanzhouChina Guideline International Network Asia China Key Laboratory of Evidence Based Medicine and Knowledge Translation of Gansu Province Lanzhou UniversityLanzhouChina Lanzhou University GRADE Center China

*** of coronavirus disease 2019(COVID-19)clinical practice guidelines(CPGs)and expert consensus statements have been developed and published since the outbreak of the ***,these CPGs are of widely variable ***,this review is aimed at systematically evaluating the methodological and reporting qualities of COVID-19 CPGs,exploring factors that may influence their quality,and analyzing the change of recommendations in CPGs with evidence *** searched five electronic databases and five websites from 1 January to 31 December 2020 to retrieve all COVID-19 *** assessment of the methodological and reporting qualities of CPGs was performed using the AGREE II instrument and RIGHT *** and evidence used to make recommendations in the CPGs regarding some treatments for COVID-19(remdesivir,glucocorticoids,hydroxychloroquine/chloroquine,interferon,and lopinavir-ritonavir)were also systematically *** the statistical inference was performed to identify factors associated with the quality of *** included a total of 92 COVID-19 CPGs developed by 19 ***,the RIGHT checklist reporting rate of COVID-19 CPGs was 33.0%,and the AGREE II domain score was 30.4%.The overall methodological and reporting qualities of COVID-19 CPGs gradually improved during the year *** associated with high methodological and reporting qualities included the evidence-based development process,management of conflicts of interest,and use of established rating systems to assess the quality of evidence and strength of *** recommendations of only seven(7.6%)CPGs were informed by a systematic review of evidence,and these seven CPGs have relatively high methodological and reporting qualities,in which six of them fully meet the Institute of Medicine(IOM)criteria of ***,a rapid advice CPG developed by the World Health Organization(WHO)of the seven CPGs got the highest overa

关键词： register formal transparency

低/超低烟碱含量烟叶生产途径及对烟叶化学成分和质量的影响

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国烟草学报 2018年第5期24卷 102-111页

作者：史宏志杨惠娟王俊张梦玥任梦娟河南农业大学国家烟草栽培生理生化研究基地/烟草行业烟草栽培重点实验室郑州450002

烟碱是烟叶和烟气中重要的具有生理活性的化学成分,大幅度降低烟碱含量对烟叶化学组成和感官质量会产生显著影响。目前虽然可通过遗传育种、遗传工程、农艺调控和化学萃取等途径在一定程度上实现低/超低烟碱含量烟叶生产,但能否大规模... 详细信息

烟碱是烟叶和烟气中重要的具有生理活性的化学成分,大幅度降低烟碱含量对烟叶化学组成和感官质量会产生显著影响。目前虽然可通过遗传育种、遗传工程、农艺调控和化学萃取等途径在一定程度上实现低/超低烟碱含量烟叶生产,但能否大规模投入使用尚存在不确定性。本文针对烟碱管控这一国际烟草界热点问题,围绕低烟碱烟叶生产途径和特点,低烟碱烟叶化学成分和烟叶质量变化等进行了全面综述,并对低烟碱烟叶生产和应用的可行性和局限性进行了分析和展望。

关键词：低烟碱烟叶遗传工程化学成分质量

在线全文

学校读者我要写书评

暂无评论

基于烟茄嫁接的低烟碱烟草烟叶化学成分变化

中国烟草学报 2018年第6期24卷 42-48页

作者：任梦娟史宏志顿松阳杨惠娟李洪亮河南农业大学国家烟草栽培生理生化研究基地/烟草行业烟草栽培重点实验室郑州450002 河南省烟草公司许昌市公司襄城县分公司河南许昌461700

为探索通过嫁接技术有效降低烟叶烟碱含量的技术,以茄子为砧木,云烟87为接穗,采用盆栽试验研究了烟茄嫁接生产低烟碱烟叶的可行性和烟叶化学成分的变化。试验共设烟/烟、烟/茄不培土、烟/茄培土等3个处理。结果表明:烟茄嫁接,烟株植物... 详细信息

为探索通过嫁接技术有效降低烟叶烟碱含量的技术,以茄子为砧木,云烟87为接穗,采用盆栽试验研究了烟茄嫁接生产低烟碱烟叶的可行性和烟叶化学成分的变化。试验共设烟/烟、烟/茄不培土、烟/茄培土等3个处理。结果表明:烟茄嫁接,烟株植物学特征和农艺性状未显著改变,烟叶烟碱含量降至极低水平,鲜烟叶中烟碱含量低至0.08%,烤后烟烟叶烟碱含量低至0.10%,比对照降低95%,假木贼碱和降烟碱含量也有所降低,但假木贼碱的下降比例较小,表明假木贼碱在叶片中有一定的合成能力,新烟草碱在鲜烟叶和烤后烟中均未检测到。在接穗底部培土诱发了不定根产生,能够促进生物碱的合成,导致烟/茄培土的烟碱含量比烟/茄不培土明显升高;烟茄嫁接的烟叶叶绿素含量显著高于对照,成熟较慢,蛋白质、淀粉、总氮含量较高,总糖、还原糖含量降低。本研究为通过农业措施选择性降低和调节烟叶烟碱含量提供了新的途径。

关键词：烟草茄子嫁接低烟碱化学成分

Iron-handling solute carrier SLC22A17 as a blood-brain barrier target after stroke

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第11期20卷 3207-3208页

作者： Xueqi ren Wenlu Li Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Neuroprotection Research Laboratories Departments of Radiology and NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

The pathophysiology of ischemic stroke is complex and multifactorial,involving various forms of cell death such as apoptosis,autophagy,and necrosis.A recent study suggests that oxidative and inflammatory stress can induce ferroptosis,a specialized form of cell death characterized by the accumulation of lipid peroxides dependent on intracellular iron overload(Li and Jia,2023).

关键词： death specialized barrier

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan ren Fei Zheng Tingwei Cao Qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

中文系统评价与Cochrane系统评价的重复性研究

在线全文

学校读者我要写书评

暂无评论

中国循证医学杂志 2023年第12期23卷 1434-1441页

作者：兰慧任梦娟孙雅佳吴守媛刘云兰王平刘兴荣陈耀龙兰州大学公共卫生学院兰州730000 兰州大学基础医学院循证医学中心兰州730000 兰州大学健康数据科学研究院兰州730000 世界卫生组织指南实施与知识转化合作中心兰州730000 Cochrane中国协作网兰州大学分中心兰州730000 兰州大学GRADE中心兰州730000

目的调查中文系统评价(Systematic review,SR)与Cochrane SR在脑卒中领域的重复性。方法计算机检索CNKI、WanFang Data、CBM和Cochrane Library数据库,搜集脑卒中领域发表的中文SR与Cochrane SR,检索时限均为2012年至2022年。通过提... 详细信息

目的调查中文系统评价(Systematic review,SR)与Cochrane SR在脑卒中领域的重复性。方法计算机检索CNKI、WanFang Data、CBM和Cochrane Library数据库,搜集脑卒中领域发表的中文SR与Cochrane SR,检索时限均为2012年至2022年。通过提取脑卒中领域所有干预性系统评价的人群(population,P)、干预(intervention,I)、对照(comparison,C)、结果(outcome,O),分析SR的重复性,并进一步提取PICO重复的SR的基本信息和研究信息,进行描述性分析。结果共纳入1 303篇文献,其中1 192篇中文SR,111篇Cochrane SR。重复性分析结果显示,128篇中文SR与29篇Cochrane SR在PICO方面存在重复。大部分(127/128,99.2%)中文SR的发表时间晚于Cochrane SR,重复性SR的发表年份呈逐年增长趋势。结论我国学者开展的SR工作存在不容忽视的重复性研究问题,在注册、计划书撰写、文献检索等方法方面缺少严格的规范和引导,造成极大的资源浪费,需要进一步加强规范约束和引导,坚持问题导向和质量意识,强化SR培训,减少重复性研究。

关键词：系统评价 Cochrane系统评价脑卒中重复性

^(60)Co-γ射线辐照对雪茄烟叶发酵微生物和代谢物变化及烟叶质量的影响

在线全文

学校读者我要写书评

暂无评论

中国烟草学报 2024年第2期30卷 125-134页

作者：张蓝月秦艳青赵园园任梦娟张瑞娜史宏志河南农业大学烟草学院/烟草农业减害研究中心郑州450002 四川省烟草公司成都市600041 四川省烟草公司德阳市公司四川省德阳市618400

【目的】通过^(60)Co-γ射线辐照灭菌,明确微生物在雪茄烟叶发酵过程中的重要作用。【方法】以四川雪茄烟品种德雪1号为试验材料,以剂量10 kGy的^(60)Co-γ射线对发酵前烟叶进行辐照处理,测定分析发酵过程中烟叶微生物多样性、代谢组学... 详细信息

【目的】通过^(60)Co-γ射线辐照灭菌,明确微生物在雪茄烟叶发酵过程中的重要作用。【方法】以四川雪茄烟品种德雪1号为试验材料,以剂量10 kGy的^(60)Co-γ射线对发酵前烟叶进行辐照处理,测定分析发酵过程中烟叶微生物多样性、代谢组学、中性香气成分和常规化学成分含量。【结果】(1)辐照组烟叶发酵28 d样本经传统分离培养和Illumina MiSeq高通量测序均未发现细菌群落。(2)非靶向代谢组学结果显示,辐照组烟叶发酵28 d后芸香苷、根皮苷和山奈酚等多酚类物质,山奈酚-3-O-芸香糖苷等多酚糖苷类物质,二肽等含量高于未辐照组烟叶,而亮氨酸、L-丝氨酸和脯氨酸等氨基酸含量低于未辐照烟叶。KEGG富集差异显著的代谢通路是黄酮和黄酮醇生物合成通路与花生四烯酸代谢通路。(3)发酵28 d后,两组烟叶的生物碱、还原糖、总糖、淀粉和蛋白质含量均显著降低,辐照组烟叶发酵前后各指标的降幅小于未辐照烟叶。辐照组烟叶发酵28 d后中性香气成分总量显著低于未辐照烟叶,而棕色化反应产物总量显著增加,烟叶劲头、杂气、刺激性更大。【结论】对发酵前烟叶进行10 kGy^(60)Co-γ射线辐照可有效杀灭烟叶细菌,发酵28 d后大分子物质降解转化低于未辐照烟叶,感官质量增加幅度减小,但相比于发酵前仍有一定程度的改善。

关键词：雪茄烟叶 ^(60)Co-γ射线发酵微生物代谢组学烟叶质量

减氮条件下喷施壳寡糖对烤烟氮素利用率及烟叶品质的影响

在线全文

学校读者我要写书评

暂无评论

烟草科技 2018年第11期51卷 14-19页

作者：任梦娟段卫东孙军伟申洪涛杨惠娟王俊胡坤史宏志河南农业大学国家烟草栽培生理生化研究基地郑州市农业路63号450002 河南中烟工业有限责任公司郑州市榆林南路16号450047 云南省烟草公司大理州公司云南省大理市鹤庆路71号671000

为探索烤烟减肥增效技术,以烤烟品种红花大金元为试验材料,采用田间试验,在减施氮肥条件下设置0、80、105和130 mg/L等4个壳寡糖浓度处理,分别在移栽后30、40、50和60 d喷施烟株,研究了烤烟喷施壳寡糖对烤烟氮素利用率和烟叶品质的影响... 详细信息

为探索烤烟减肥增效技术,以烤烟品种红花大金元为试验材料,采用田间试验,在减施氮肥条件下设置0、80、105和130 mg/L等4个壳寡糖浓度处理,分别在移栽后30、40、50和60 d喷施烟株,研究了烤烟喷施壳寡糖对烤烟氮素利用率和烟叶品质的影响。结果表明,减氮未喷施壳寡糖烟株田间长势较差,烤烟产量和品质较低。在减施氮肥20%条件下,喷施壳寡糖可促进烟株打顶前的生长,提高烟株对氮素的吸收量和氮素利用率,且随着壳寡糖浓度的增加效果更明显。减施氮肥20%配合喷施105 mg/L壳寡糖处理的烤烟上等烟比例和感官品质均优于常规施氮量的对照;与常规施氮量的对照相比,产值增加26.33%,氮肥表观利用率和农艺利用率分别增加39.33%和61.02%。因此,在烤烟氮肥减施条件下,烟株生长前期喷施壳寡糖水溶肥具有显著的增质增效作用。

关键词：烤烟壳寡糖产量品质氮肥利用率