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类星体HⅠ谱线的切仑柯夫红移与线强比I(Lyα)/I(Hβ)的关系

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天体物理学报 1989年第3期9卷 218-223页

作者：晏明尤峻汉程富华中国科学技术大学天体物理中心

在切仑柯夫线发射理论的框架下,本文统一地讨论了类星体HI谱线的切合柯夫红移与线强比I(Lyα)/I(Hβ)之间的内在关系。忽略类星体宽线区气云外层光薄区中HI复合线的贡献,利用观测到的Lyα线相对于CIV线的相对红移,即切金柯夫红移,定出... 详细信息

在切仑柯夫线发射理论的框架下,本文统一地讨论了类星体HI谱线的切合柯夫红移与线强比I(Lyα)/I(Hβ)之间的内在关系。忽略类星体宽线区气云外层光薄区中HI复合线的贡献,利用观测到的Lyα线相对于CIV线的相对红移,即切金柯夫红移,定出第二能级上粒子数布居R_2～0.02,利用观测的〈I(Hα)/I(Hβ)〉值定出参量x_β～14.0。在给定参量T～11000K时,HI的巴尔末线的切仑柯夫红移与线强比I(Lyα)/I(Hβ)同时与观测值相符甚佳,这对切仑柯夫线发射理论是一个有力的支持。

关键词：类星体 HI谱线红移线强比

The changing pattern of renal osteodystrophy

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肾脏病与透析肾移植杂志 1996年第2期 1-9+95页

作者： Allen C.Alfrey William e.Huffer Department of Medicine and Pathology Denver V.A.Medical Center and University of Colorado Health Sciences Center USA Department of Medicine and Pathology Denver V.A.Medical Center and University of Colorado Health Sciences Center USA

Aluminum intoxication has been a ma-jor cause of morbidity and mortality in dia-lyzed uremic *** the last 7-years means to markedly reduce aluminumexposure in this population have been *** study was carried out to de-termine how effective restriction of alu-minum exposure has been in preventing alu-minum loading and toxicity in uremic *** All bone histology processed onpatients with end-stage renal disease(452patients)between January 1984 and Decem-ber 1991 were *** were performed and bones dividedinto four major grouping:①high turnover,osteitis firosa;②low turnover,osteomala-cia;③low turnover,adynamic and ④mixedtype bone *** Between 1985 and 1991 a signifi-cant decrease in aluminum loading wasfound in patients with end-stage renal dis-ease as determined by a fall in plasma alu-minum from 74±30 μg/L to 12±7 μg/L and decrease in aluminum positive bonespecimens from 87.2% to 35.8%(Pe reduction in aluminumloading low turnover osteomalacic bone dis-ease decreased from 11.6% to less than 5%(Pe total bone specimensstudied and the fraction of mixed bone dis-ease with osteomalacic features decreasedfrom 33% to 19%(Pere was nochange in the other types of bone *** The present methods of limit-ing aluminum exposure in dialysis patientsappears to be fairly effective in preventingaluminum loading and skeletal toxicity,manifested as a mineralization ***-ever,aluminum restriction had no influenceon high turnover bone disease or the ady-namic type of low turnover disease support-ing a different etiology for these two typesof bone disease.

关键词： aluminum uremia osteomalacia hyperparathyroid bone

exploitation of the antibacterial,antibiofilm and antioxidant activities of Salvadora Persica(Miswak)extract

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Journal of Bioresources and Bioproducts 2023年第1期8卷 59-65页

作者： Gamal M.el-Sherbiny Ahmed Mohamed Gazelly Mohammed H.Sharaf Saad A.Moghannemm Shehata M.e Mahmoud K.A.Ismail Ahmad S.el-Hawary Botany and Microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt

The Salvadora persica(***)*** stick,usually known as miswak,is still being em-ployed as an oral hygiene agent for plaque and gingivitis *** study aims to assess the antibacterial,antibiofilm,antioxidant,and phytochemical profile of *** *** ***-sica was purchased from a local market,grinded and extracted with petroleum *** disk dif-fusion,microdilution,and micro-plate assays were performed to evaluate the antibacterial and an-tibiofilm activities of the prepared extract at different concentrations against𝛽-lactam resistance Streptococcus *** radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)and stable radical cationic chromophore,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate)(ABTS)methods were used to determine their antioxidant *** and spectrometric analyses were performed using gas chromatography-mass(GC-MS)*** minimum inhibitory concentration(MIC)of *** extract against𝛽-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/*** maximum suppression of biofilm formation by *** extract was observed at MIC with a percentage of 68.66%,against Streptococcus *** *** ex-tract exhibited antioxidant activity with IC 50 of 20μg/mL and 35μg/mL from DPPH and ABTS,*** phytochemical characterization showed the presence of 22 compounds with ma-jor compounds;benzyl isothiocyanate(36.21%)and n-hexadecanoic acid(27.62%).The *** extract exhibited antibacterial activity against𝛽-lactam resistant Streptococcus species,showing a promising natural alternative that could be a treatment option.

关键词： β-lactam resistance Streptococcus species S.persica extract Antibacterial Antibiofilm Antioxidant GC-MS analysis

The αMβ2 integrin and its role in neutrophil function

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Cell Research 1999年第3期9卷 171-178页

作者： ZHANG LI (Department of Vascular Biology, American Red Cross,Holland La6oratory, 15601 Crabbs Branch Way, Rockville,MD 20855 USA)Tel: 301-738-0657 Fax: 301-738-0465e-mail: zhangl@u8a.redcross. org 1Department of Vascular Biology American Red Cross Holland Laboratory 15601 Crabbs Branch Way Rockville MD 20855 USA Tel: 301-738-0657 Fax: 301-738-0465 e-mail: zhangl@***

Neutrophils are the first cell type to arrive at the in-jury sites and play a critical role in host defense, by virtueof its ability to adhere and transmigrate through endothe-lium, to phagocytose foreign pathogens, and to producefree oxygen radicals and proteolytic enzymes. Yet, inap-propriate neutrophil activation causes tissue damage andvarious inflammatory diseases. These physiological andpathological functions of neutrophils depend on the en-gagement of certain surface receptors, especially αMβ2,the ma jor β2 integrin receptor present on neutrophil sur-face. Understanding of the molecular mechanisms under-lying ligand binding by αMβ2, as well as the roles of αMβ2-ligand interactions in neutrophil functions will enable usto regulate more precisely neutrophil activities: that is,to promote their host defense functions, and at the sametime to minimize their deleterious effects on normal cells.

关键词： Leukocyte integrn receptor adhesion

A comparative study on Canadian and Chinese river basin planning

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Journal of environmental Sciences 1994年第2期6卷 224-233页

作者： Guo Huaicheng (Center of environmental Sciences,Peking University, Beijing 100871,China)G. Beanlands ( School for Resource & environmental Studies,Dalhousie University, Halifax, Canada B3H 3e2)

The paper tries to summarize basic approaches to river basin planning in Canada andin China, and makes a comparative analysis taking the Saint John River in Canada and the TaiziRiver in China as examples. The analytical results indicated that policy and management are the ma-jor features of the river basin planning study in Canada; control and treatment of water pollutionhave been generally treated in China; lack of implementation is a common problem in bothcountries.

关键词： river basin planning public participation water pollution.

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高血压治疗期间左心室质量改变的预后价值

世界核心医学期刊文摘（心脏病学分册） 2005年第4期1卷 19-20页

作者： Devereux R.B. Wachtell K. Gerdts e. 王亭忠 New York Presbyterian Hospital Weill Cornell Medical Center 525 E 68th St New York NY 1002 1 United States Dr.

Context: Increased baseline left ventricular(LV) mass predicts cardiovascular( CV) complications of hypertension, but the relation between lower LV mass and ou tcome during treatment for hypertension is uncertain. Objective: To determine wh ether reduction of LV mass during antihypertensive treatment modifies risk of ma jor CV events independent of blood pressure change. Design, Setting, and Partici pants: Prospective cohort substudy of the Losartan Intervention For endpoint Red uction in Hypertension(LIFe) randomized clinical trial, conducted from 1995 to 2 001. A total of 941 prospectively identified patients aged 55 to 80 years with e ssential hypertension and electrocardiographic LV hypertrophy had LV mass measur ed by echocardiography at enrollment in the LIFe trial and thereafter were follo wed up annually for a mean(SD) of 4.8(1.0) years for CV events. Main Outcome Mea sures: Composite end point of CV death, fatal or nonfatal myocardial infarction, and fatal or nonfatal stroke. Results: The composite end point occurred in 104 patients(11%). The multivariable Cox regression model showed a strong associati on between lower intreatment LV mass index and reduced rate of the composite C V end point(hazard ratio[HR], 0.78 per 1SD(25.3) decrease in LV mass index; 95 %confidence interval[CI], 0.65-0.94; P=.009) over and above that predicted by reduction in blood pressure. There were parallel associations between lower in treatment LV mass index and lower CV mortality (HR, 0.62; 95%CI, 0.47-0.82; P= .001), stroke (HR, 0.76; 95%CI, 0.60-0.96; P=.02), myocardial infarction (HR, 0.85; 95%CI, 0.62-1.17, P=.33), and allcause mortality (HR, 0.72; 95%CI, 0. 59-0.88, P=.002), independent of systolic blood pressure and assigned treatment . Results were confirmed in analyses adjusting for additional CV risk factors, e lectrocardiographic changes, or when only considering events after the first yea r of study treatment. Conclusion: In patients with essential hypertension and

关键词：左心室质量预后价值非致命性脑卒中终点事件复合终点心电图改变致命性心肌梗死临床终点洛沙坦亚组

水稻种子在不同气候区室温贮藏的适宜含水量及存活特性

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中国水稻科学 2009年第6期23卷 621-627页

作者：胡群文卢新雄辛萍萍陈晓玲张志娥辛霞刘旭中国农业科学院作物科学研究所/农业部作物种质资源与生物技术重点开放实验室北京100081 安徽省安庆市种植业管理局安徽安庆246001

将不同含水量水平的两个水稻品种幸实(粳稻)和桂朝2号(籼稻)分别贮藏在三亚、南昌、北京、西宁、乌鲁木齐和哈尔滨等6个不同气候类型地区。通过11年的逐年生活力测定,研究了水稻种子室温贮藏的适宜含水量及其存活特性。结果表明,水稻种... 详细信息

将不同含水量水平的两个水稻品种幸实(粳稻)和桂朝2号(籼稻)分别贮藏在三亚、南昌、北京、西宁、乌鲁木齐和哈尔滨等6个不同气候类型地区。通过11年的逐年生活力测定,研究了水稻种子室温贮藏的适宜含水量及其存活特性。结果表明,水稻种子经适当干燥后其生活力和活力没有显著下降。但当种子含水量在3.0%以下时种子的生活力和活力受到影响。获得了水稻种子在三亚、南昌室温贮藏时(贮藏温度不是恒定的)的适宜含水量,且适宜含水量5.0%～6.5%具有地域的广适性。相对于其他含水量,适宜含水量种子在贮藏过程中,其生活力快速下降阶段推迟,且适宜含水量上限和极差与贮藏地点年均温和≥0℃积温呈显著或极显著负相关,且适宜含水量下限与之呈显著或极显著正相关。种子在年均温度相同的西宁和乌鲁木齐的贮藏效果不同,≥0℃积温和气候温差波动的差值可能是其主要影响因素。

关键词：水稻种子室温贮藏适宜含水量种子生活力发芽特性

7大类623种预包装食品营养标签标示情况调查分析

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中国健康教育 2018年第1期34卷 46-50页

作者：姜迎于连龙孙青王淑娥王连森闫静弋刘丹茹王克波张俊黎褚遵华山东省疾病预防控制中心山东济南250014 济南军区总医院山东济南250031 山东大学公共卫生学院山东济南250012

目的了解7大类623种预包装食品营养标签的标示情况,并对结果进行分析。方法在济南市的各型超市和商品零售点,现场调查或购买符合调查条件的预包装食品,将营养标签等相关信息输入调查表中,用SPSS 18.0软件进行统计分析。结果在调查的7大... 详细信息

目的了解7大类623种预包装食品营养标签的标示情况,并对结果进行分析。方法在济南市的各型超市和商品零售点,现场调查或购买符合调查条件的预包装食品,将营养标签等相关信息输入调查表中,用SPSS 18.0软件进行统计分析。结果在调查的7大类623种预包装食品中,营养标签的标示率为94.1%,标示规范率为95.7%;进行营养声称的有58份,占9.31%;进行营养成分功能声称的有71份,占11.40%;营养声称和功能声称频次较高的营养素均为钙。豆制品的强制性标示规范率为100.0%;谷类制品的营养标签强制性标示之间的差异具有统计学意义。结论济南市预包装食品营养标签标示率和规范性较高,但仍存在一定的标示不规范、可选择标示率较低的问题。相关部门应加强对企业的教育监管,扩大营养标签在防治慢性非传染性疾病中的影响。

关键词：预包装食品营养标签标示