Pseudomonas fluorescens sp-f铁载体高效液相凝胶色谱分析

利用高效液相凝胶色谱法对荧光假单胞菌所产铁载体进行了分析,结果显示高产铁载体P.fluorescens sp-f与P.fluorescens AB92001均可分泌3种铁载体,其中具有荧光的pyoverdine容易被细胞外的铁抑制。高效液相凝胶色谱法适用于假单胞菌铁载体的分析检测。     

假单胞菌荧光与非荧光铁载体对铁离子的应答差异

假单胞菌既能产荧光铁载体也能产非荧光铁载体.通过对假单胞菌在不同铁离子浓度下,在通用CAS(Chrome azroul S)检测平板、改进的蔗糖-天冬氨酸(SA)平板(MSA)上以及通用液体CAS培养基和MSA培养基内的铁载体产生情况的比较,发现在通用CAS的液体培养基上产生的主要为非荧光铁载体(pyochelin),而在改进的MSA培养基上产生的主要为荧光铁载体(pyoverdine);在铁离子的应答方面,pyoverdine较pyochelin灵敏,较低的铁离子浓度即可抑制荧光铁载体的产生,但是不能抑制非荧光铁载体.     

高灵敏假单胞菌铁载体的平板检测方法*

CAS蓝色检测平板是一种筛选、检测各类细菌铁载体的常用方法,而蔗糖-天冬酰氨培养基被用于假单胞菌产铁载体规律的研究。用天冬氨酸替代天冬酰氨,将CAS蓝色检测液与蔗糖-天冬氨酸培养基(MSA培养基)相结合,得到一种改进的MSA-CAS检测平板。通过对假单胞菌属7个种8个株进行荧光与非荧光铁载体检测方面的比较研究,结果表明MSA-CAS检测平板假单胞菌铁载体的检测灵敏度比通用CAS检测平板高,而且在检测荧光铁载体方面具有荧光背景低、荧光铁载体晕圈明显和晕圈与背景的对比度大的优点。     

高灵敏假单胞菌铁载体的平板检测方法

CAS蓝色检测平板是一种筛选、检测各类细菌铁载体的常用方法,而蔗糖-天冬酰氨培养基被用于假单胞菌产铁载体规律的研究。用天冬氨酸替代天冬酰氨,将CAS蓝色检测液与蔗糖-天冬氨酸培养基（MSA培养基）相结合,得到一种改进的MSA-CAS检测平板。通过对假单胞菌属7个种8个株进行荧光与非荧光铁载体检测方面的比较研究,结果表明MSA-CAS检测平板假单胞菌铁载体的检测灵敏度比通用CAS检测平板高,而且在检测荧光铁载体方面具有荧光背景低、荧光铁载体晕圈明显和晕圈与背景的对比度大的优点。     

一株花生根际铁载体产生菌的分离鉴定及耐药性分析

目的：从花生根际筛选铁载体产生能力较强的菌株,对其进行鉴定及耐药性分析。方法：用梯度稀释法从花生根际中分离出细菌,在刃天青（CAS）检测平板上依显色圈的大小从中筛选出一株铁载体产生能力较强的菌,并对其进行生理生化鉴定和16S rDNA序列分析,用抗生素梯度平板检测其对9种常见抗生素的抗性。结果：筛选出一株产铁载体的菌株D15,13项生理生化指标除甲基红试验呈阳性外,其他均与恶臭假单胞菌相同;其16S rDNA与恶臭假单胞菌的同源性为100%;该菌对氨苄青霉素、氯霉素、利福平、红霉素、新霉素、链霉素、四环素都有不同程度的的抗性,对卡那霉素和庆大霉素表现较强的敏感性。结论：获得铁载体产生菌D15,经鉴定为恶臭假单胞菌,该菌耐药性符合用转座子诱变法研究铁载体合成的相关基因的条件。     

小麦根圈细菌铁载体的检测

本文报道微生物铁载体定性与定量测定的方法,以及小麦根圈细菌铁载体的室内检测结果。２２株小麦根圈耐寒细菌和２株固氮菌在定性检测平板上产生铁载体,另有３株固氮菌不产。定量测定结果表明：３６株水溶性色素产生菌合成铁载体的量在０．７１５－０．１０６（Ａ／Ａｒ）之间,其中属于荧光假单胞菌群的２５个菌株铁载体产量的测定值（Ａ／Ａｒ）在０．１８４－０．１０６之间,达极高量水平。     

绿针假单胞菌色素的研究

对假单胞菌产生的色素已有报道。我们从我国东北地区的土壤中分离出一株假单胞菌,经鉴定定名为绿针假单胞菌(Pseudomonas chlororaphis)。在斜面上培养,它能产生色素结晶(见图1),本文报道这种结晶的分离方法、物理化学特性、抗菌性能和毒性。     

一株新的具有脱色能力的琼脂分解菌

本文报道了一株具有脱色能力的琼脂分解菌的分离、脱色现象及细菌学鉴定结果。该菌株分离自琼脂生产工厂周围的土壤中。它能在琼脂培养基上脱除废糖蜜的黑褐色色素,能分解淀粉和琼脂,利用纤维素生长,液化明胶。培养新分离菌不需要生长因子,不产生吲哚、硫化氢、荧光色素及扩散性色素。新分离菌是假单胞菌属的一个新种,定名为井式假单胞菌(Pseudo-monas wellantypicum n．Sp．)。     

具ACC脱氨酶活性的碱蓬内生细菌的分离、鉴定及其生物学特性

【目的】具有1-氨基环丙烷-1-羧酸(ACC)脱氨酶活性的盐生植物碱蓬内生细菌的分离及生物学特性的研究有助于探索内生细菌与宿主植物耐盐性的关系。【方法】采用研磨法从健康碱蓬植株的根、茎、叶中分离具有ACC脱氨酶活性的碱蓬内生细菌,根据形态特征、生理生化、API鉴定系统和16S rRNA对菌种进行鉴定,并分别测定了菌株产ACC脱氨酶、铁载体、吲哚乙酸、赤霉素、脱落酸、蛋白酶及溶磷、固氮和拮抗病原菌的特性。【结果】将分离得到的内生细菌LP11、SS12、TW1和TW2分别鉴定为栖稻假单胞菌(Pseudomonas oryzihabitans)、假单胞菌(Pseudomonas sp.)、成团泛菌(Pantoea agglomerans)和恶臭假单胞菌(Pseudomonas putida),4株菌除具有较高的ACC脱氨酶活力之外,还可不同程度地产生铁载体、吲哚乙酸、赤霉素和脱落酸,且均有溶磷作用,但无固氮能力及蛋白酶活力,唯有菌株SS12对萝卜枯萎病菌(Fusariumoxysporum f.sp.conglutinans)和黄瓜枯萎病菌(F.oxysporum f.sp.cucumerinum)具有拮抗作用。【结论】从盐生植物碱蓬中分离到的假单胞菌属和泛菌属内生细菌,具有丰富多样的生物学特性。     

铜绿假单胞菌fur基因缺失突变株的构建及其表型分析

铁摄取调节蛋白(ferric uptake regulator, Fur)是控制铜绿假单胞菌铁代谢和毒力的关键调节因子。许多课题组尝试构建铜绿假单胞菌fur的缺失突变株均失败,因此铜绿假单胞菌的fur一直被认为是必需基因,这导致其生物学功能一直未得到全面的解析。【目的】构建铜绿假单胞菌fur的缺失突变株,并对该突变株的表型进行分析。【方法】以铜绿假单胞菌PAO1为亲本菌株,通过同源重组的方法构建fur缺失突变株,研究该基因对铜绿假单胞菌生长、铁载体生物合成、抗氧胁迫能力、鞭毛形成、生物被膜形成和毒力等的影响。同时,通过遗传分析对fur缺失突变株生长缺陷表型的原因进行探究。【结果】本研究成功构建了铜绿假单胞菌fur基因的缺失突变株,发现缺失突变fur极大地限制了铜绿假单胞菌的生长能力,并降低了该菌对限铁环境的生长适应性,但不影响该菌对高铁环境的生长适应性。铜绿假单胞菌Δfur的这种生长缺陷表型是细胞生长增殖变慢造成的,而不是诱导细胞死亡引起的。然而,其他异源的fur基因能完全互补Δfur的这种生长缺陷表型,暗示铜绿假单胞菌的Fur蛋白在功能上不存在独特性。尽管Fur与毒素-抗毒素系统PacTA存在功能关联性,但是铜绿假单胞菌Δfur的这种生长缺陷表型却与PacT毒素无关。除了影响铜绿假单胞菌的生长表型,缺失突变fur还使铜绿假单胞菌丧失了对铁载体生物合成的抑制作用,导致该菌对H₂O₂更敏感并丧失了鞭毛的形成能力,同时降低了该菌对大蜡螟幼虫的毒力。此外,缺失突变fur还显著提升了铜绿假单胞菌的胞内环二鸟苷酸(cyclic diguanylate, c-di-GMP)水平,从而诱导pelF和pslA基因的表达,进而促进铜绿假单胞菌生物被膜的形成。【结论】fur是可以缺失的非必需基因,在铜绿假单胞菌的正常生长、铁载体生物合成、抗氧胁迫能力、鞭毛形成、生物被膜形成和毒力等方面都发挥着十分重要的作用,这为针对铜绿假单胞菌的疫苗和抗菌药物开发奠定了基础。     

Exercise-induced hormone responses in girls at different stages of sexual maturation

The dependence of exercise-induced hormone responses on sexual maturation was tested in a 3-year longitudinal experiment on 34 girls (aged 11–12 years at the beginning). Sexual maturation was evaluated by Tanners five-stage scale. Children cycled for 20-min at 60% maximal oxygen uptake once a year. Cortisol, insulin, growth hormone, β-oestradiol, progesterone and testosterone concentrations in venous blood were determined by radioimmunoassay procedures. Basal concentrations of growth hormone increased and of cortisol decreased when breast stage III was reached. Reaching breast stage IV was associated with an increase in basal concentrations of β-oestradiol, progesterone and testosterone. The exercise induced significant increases in concentrations of cortisol, growth hormone and β-oestradiol and a decrease in insulin concentration. At breast stage III the increase in cortisol concentration was to a lower level [467 (SEM 42) vs 567 (SEM 46)nmol · l⁻¹] and growth hormone concentration to a higher level [29.4 (SEM 0.5) vs 12.8 (SEM 0.4)ng · ml⁻¹], while the fall in insulin concentration was less pronounced [postexercise level 10.6 (SEM 0.9) vs 7.8 (SEM 0.8)mU · l⁻¹] than in stage II. The magnitude of the cortisol response was reduced in the last stage of breast development (+42.1% vs +55.5% at stage II, +66.2% at stage III, and +50.0% at stage IV). The magnitude of β-oestradiol response was the lowest in breast stage IV (+15.8%) and the highest at stage V (+41.1%). The progesterone response became significant at stage IV and testosterone response at stage V. In conclusion, we found that reaching breast stage III was associated with altered responses of cortisol, insulin and growth hormone concentrations while the responses of the sex hormone concentrations became pronounced in the last stages of sexual maturation. Accepted: 17 September 1997     

Rethinking the deserving body: altruism,markets, and political action in health care provision

Abstract

I seek to understand two dimensions in the evolution and practices of medical institutions in the USA. First, I ask, how and why do medical organizations limit, suspend, or redirect profit-oriented functions to abide by principles of altruism and still survive in a competitive market economy? Reaching out to poor and immigrant populations entails non-economic factors, including the deployment of religious and humanitarian narratives. Conversely, the extent and character of legislative actions supporting philanthropic endeavours is closely related to mobilization at the grassroots level. I investigate the ways in which community organizations bring about changes to support practices that confound, at least to some extent, market expectations and underscore the significance of political action to secure health care services on behalf of low-income populations, including immigrants.     

关于苏北地区某三甲医院进口与国产医疗设备和耗材使用情况及反馈的研究．

目的：初步了解了进口与国产医疗设备与耗材的发展状况和使用反馈情况,并对国内医疗设备与耗材行业的发展提供合理化建议。方法：通过对苏北地区某三级甲等医院设备科工作人员、医生、护士长、患者及患者家属进行调研或访谈,并以调研和访谈的统计结果为依据得出结论并提出建议。结果：技术成熟的中小型医疗设备或耗材,从质量、价格等因素综合考虑,国内产品优于进口产品,一定程度上得到了医务人员和消费者的认可。在高端大中型医疗设备与耗材方面,进口产品具有较大的技术优势。结论：国内医疗设备生产企业应当积极开展研发工作,提高产品的技术含量与质量,巩固自身在中小型医疗设备与耗材方面的优势,并努力在高端大中型医疗设备与耗材方面取得突破。     

关于苏北地区某三甲医院进口与国产医疗设备和耗材使用情况

目的:初步了解了进口与国产医疗设备与耗材的发展状况和使用反馈情况,并对国内医疗设备与耗材行业的发展提供合理化建议。方法:通过对苏北地区某三级甲等医院设备科工作人员、医生、护士长、患者及患者家属进行调研或访谈,并以调研和访谈的统计结果为依据得出结论并提出建议。结果:技术成熟的中小型医疗设备或耗材,从质量、价格等因素综合考虑,国内产品优于进口产品,一定程度上得到了医务人员和消费者的认可。在高端大中型医疗设备与耗材方面,进口产品具有较大的技术优势。结论:国内医疗设备生产企业应当积极开展研发工作,提高产品的技术含量与质量,巩固自身在中小型医疗设备与耗材方面的优势,并努力在高端大中型医疗设备与耗材方面取得突破。     

Hiatal surfaces from the Miocene Globigerina Limestone Formation of Malta: Biostratigraphy, sedimentology, trace fossils and early diagenesis

The Miocene Globigerina Limestone of the Maltese islands contains widespread omission surfaces with very different characteristics and origins.The terminal Lower Globigerina Limestone hardground (TLGLHg) formed during a period of falling sea level. Coccolith assemblages suggest shallowness. Sedimentary structures and trace fossil assemblages, indicate increasing frequency of storm events and erosional episodes, towards the surface. Calcite cementation which took place around Thalassinoides burrows and formed irregular nodules was followed by dissolution of aragonite. It is suggested that lithification was linked to microbial reactions involving organic matter.In contrast two later surfaces, the terminal Middle Globigerina Limestone omissionground (TMGLOg), which marks the Lower to Middle Miocene boundary, and the Fomm-ir-Rih local hardground (FiRLHg) both contain early diagenetic dolomite. Lithification took place in two phases. The dolomite is interpreted to have formed beneath the sea floor; it was subsequently exhumed and partially corroded as the precipitation of calcitic and phosphatic cements took place around burrows open to the circulation of sea water.     

Comparative study of major lipid constituents in human and monkey aorta

The contents of total lipids, phospholipids, cholesterol, triglyceride and free fatty acid in intima and media of thoracic and abdominal segments of aorta from normal human subjects and rhesus monkeys were determined. An increase in total lipids in intima as compared to that of media was noted in both species. A comparison of lipid contents of thoracic and abdominal segments from both species revealed that abdominal segment contained significantly greater lipid. Further, human thoracic and abdominal aortic intima and media had higher content of cholesterol as compared to that of monkey aorta. The differences in lipid profile in aorta of these two species have been highlighted to provide a clue with respect to the differences in the prevalence and morphology of atherosclerosis as seen in monkey and man.     

植物引种驯化研究概述

植物引种驯化是植物学的一个分支学科,该学科与植物的迁地保护和当地的经济建设紧密相关,属于应用基础研究的范畴。但有关理论和方法的研究至今仍显得比较零碎,不够系统,判断植物引种驯化成功的标准尚不够明确。本文就植物引种驯化的概念和意义、主要理论和方法、影响其成败的因子、途径和程序、判断植物引种驯化成功的标准等进行了综述和探讨,并提出了植物引种驯化的展望。     

论＂医德＂的基本范畴

医德是医疗卫生领域精神文明建设的重要部分,也是调整医务人员与病人、医务人员之间以及与社会之间关系的行为准则。医德范畴是指人们对现代医务人员职业道德和医患关系的总结,它不仅概括了医生所应履行的职责义务,而且反映着一段时间内医患关系的本质。本文通过对医德范畴内,医生的权利和义务、责任和良心、功力和荣誉、审慎和保密四类问题的阐述,探讨当下医生在工作中应该保持何种心态,如何与患者进行沟通,以期更好地提供医疗服务。     

Free and ester-bound triterpene alcohols and sterols in cellular subfractions of Calendula officinalis flowers

In the chromoplast fraction and in the chromoplast-free fraction, obtained from Calendula officinalis ligulate flowers, the contents of individual free and ester-bound triterpene alcohols and sterols as well as the fatty acid components of the ester form were determined. It was shown that all sterols and triterpene monols in both forms occur in the two subtractions investigated, whereas all diols are localized only in the chromoplast fraction. The compositions of the fatty acids esterifying monols and sterols were similar to those esterifying diols in the chromoplasts. However, the fatty acids esterifying extra-chromoplast monols and sterols were different. This result indicates that triterpene monol esters are substrates for the biosynthesis of 3-monoesters of diols.