氮离子束注入燕麦种子对M1-M2代幼苗生理生化指标的影响

采用能量为25keV的不同剂量(4×1016N /cm2、6×1016N /cm2、8×1016N /cm2、12×1016N /cm2)N 束注入燕麦种胚,研究了N 离子束注入后,燕麦M1代和M2代种子的发芽率,幼苗体内过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性,叶绿素含量、丙二醛(MDA)含量、可溶性糖及可溶性蛋白含量的影响。实验结果表明:以12×1016N /cm2剂量处理燕麦较合适,能提高燕麦M1和M2代种子的发芽率,幼苗POD、CAT活性和可溶性蛋白含量,有利于幼苗生长。     

氮离子束注入对小麦苗期耐盐性的影响

采用能量为25keV的不同剂量的N 注入新疆春小麦种胚后,研究盐胁迫对小麦幼苗体内生理生化指标的影响。结果表明,在6×1016N /cm2剂量注入新春11号时,盐胁迫后小麦幼苗的SOD活性、脯氨酸含量、可溶性糖含量、可溶性蛋白含量均增加,幼苗生长良好,说明该剂量处理新春11号有利盐胁迫下小麦幼苗的生长。     

低能离子注入对小麦种子发芽及幼苗生理生化的影响

采用能量为25keV的N 不同剂量(2×1016 N /cm2、4×1016 N /cm2、6×1016 N /cm2、8×1016 N /cm2、12×1016 N /cm2)注入新疆小麦种子,研究了N 离子束注入新疆春小麦种子后对小麦种子的发芽率、幼苗体内的丙二醛(MDA)、可溶性蛋白、可溶性糖、叶绿素、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的影响。实验结果表明:以2×1016 N /cm2 剂量处理小麦较合适,可提高小麦种子的活力,促进种子萌发和幼苗生长。2×1016 N /cm2、4×1016 N /cm2 剂量处理对新春2号、新春11号幼苗生长有利,在这两种剂量处理下新春2号三种保护酶较新春11号敏感。     

N+离子注入对干旱胁迫条件下甘草幼苗的SOD酶和CAT酶活性及丙二醛含量的影响

以低能氮离子束为诱变源,对甘草种进行注入处理后,以萌发的幼苗为材料对其在干旱胁迫条件下保护酶活性及MDA含量变化进行研究.结果表明注入后甘草种的存活率呈现马鞍形曲线变化,其中在4.1×1016N+/cm2剂量处达到鞍点,在剂量4.6×1016N+/cm2处存活率高于对照.在干旱胁迫下,随着胁迫时间的延长,离子束注入后萌发的幼苗MDA含量明显低于对照.酶活结果显示,在干旱胁迫后期,剂量4.6×1016N+/cm2处理后的甘草幼苗SOD和CAT酶活性都高于对照,说明该注入剂量处理甘草种有助于提高甘草幼苗的抗旱性能,SOD同工酶结果也证明该剂量的离子注入对干旱胁迫下同工酶谱带有所影响.     

外源GSH对盐胁迫下番茄幼苗生长及抗逆生理指标的影响

采用营养液栽培法,研究外源谷胱甘肽(GSH)对NaCl胁迫下番茄幼苗生长、根系活力、电解质渗透率和丙二醛(MDA)、脯氨酸(Pro)、可溶性糖含量以及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性的影响,为利用外源物质减轻盐胁迫伤害提供理论依据。结果显示:(1)NaCl胁迫显著抑制了番茄幼苗的生长、根系活力和SOD、POD、CAT活性,提高了电解质渗透率及MDA、Pro、可溶性糖含量;(2)外源喷施GSH能够诱导NaCl胁迫下番茄幼苗叶片抗氧化酶SOD、POD、CAT活性上调,电解质渗透率及MDA含量下降,Pro和可溶性糖含量恢复至对照水平;(3)外源喷施还原型谷胱甘肽抑制剂(BSO)使NaCl胁迫下番茄幼苗的根系活力以及抗氧化酶SOD、POD、CAT活性下降,脯氨酸含量提高;(4)喷施GSH可诱导BSO和NaCl共处理番茄植株的根系活力、SOD、POD、CAT活性提高,MDA和Pro含量降低。研究表明,外源GSH可通过提高促进盐胁迫下番茄幼苗植株渗透调节能力及清除活性氧的酶促系统的防御能力、降低细胞膜脂过氧化程度、保护膜结构的完整性,从而有效缓解NaCl胁迫对番茄幼苗生长的抑制,提高其耐盐性。     

氯化胆碱对盐胁迫黄瓜幼苗渗透调节物质及活性氧代谢系统的影响

以盐敏感型黄瓜品种津春4号为材料,采用水培方法研究了叶面喷施不同浓度(0.5、1.0和1.5 mmol·L-1)氯化胆碱(CC)对NaCl胁迫(75 mmol·L-1)下黄瓜幼苗鲜重、叶片叶绿素、渗透调节物质含量及活性氧代谢系统的影响.结果表明:(1)单独CC处理可提高黄瓜叶片的叶绿素、可溶性糖和可溶性蛋白含量以及过氧化氢酶(CAT)与过氧化物酶(POD)活性,降低O2·-产生速率,但对植株鲜重及超氧化物岐化酶(SOD)活性影响不大;(2)NaCl胁迫处理增加了黄瓜幼苗叶片中可溶性糖和可溶性蛋白含量,增强了SOD、POD和CAT活性,提高了O2·-产生速率及丙二醛(MDA)的含量,但同时降低了叶绿素含量与植株鲜重;(3)盐胁迫前CC预处理可缓解黄瓜幼苗叶绿素含量和植株鲜重的下降、以及MDA含量和O2·-产生速率的上升趋势,且进一步提高了盐胁迫下黄瓜叶片中SOD、POD和CAT活性.因此,适宜浓度的氯化胆碱可显著提高盐胁迫下黄瓜叶片的抗氧化酶活性,提高清除活性氧的能力,缓解盐胁迫对黄瓜幼苗细胞膜的伤害,增强黄瓜幼苗的耐盐性.     

低能离子注入短命植物多伞阿魏(Ferula ferulaeoides)抗性生理特征

以能量30 keV、不同剂量N 离子注入多伞阿魏(Ferula ferulaeoides)种子用以研究多伞阿魏抗性生理指标的变化,以期为保护短命植物多伞阿魏提供理论依据.试验结果表明:随离子注入剂量增大,多伞阿魏种子发芽率和发芽指数逐渐下降;超氧化物歧化酶(SOD)活性增加、过氧化物酶(POD)、和过氧化氢酶(CAT)活性逐渐升高.剂量过大时,SOD、POD和CAT活性下降;游离脯氨酸含量逐渐降低,但在6×1016N /cm2剂量时含量升高;可溶性蛋白质含量先升高再降低,6×1016 N / cm2剂量时为最高值.通过对发芽率、发芽指数的结果进行方差分析,得出低剂量N 离子注入可破除多伞阿魏种子休眠,促进种子萌发;适当剂量N 离子注入可激活保护酶、脯氨酸和可溶性蛋白的表达.     

盐胁迫对大米草幼苗某些生理指标的影响

研究了大米草幼苗在不同培养盐度(0、20、30、50、100mmol/LNaCl)下,MDA、游离脯氨酸、可溶性糖、可溶性蛋白质含量以及保护酶(SOD、POD、CAT)活性等生理指标的变化情况。结果表明:保护酶(SOD、POD、CAT)活性在盐胁迫40d前逐渐上升且达显著差异。随着胁迫时间延长,MDA含量与CK相比逐渐降低。随着盐分胁迫浓度的增加及盐胁迫时间延长,大米草叶片中游离脯氨酸、可溶性糖、可溶性蛋白质含量呈上升趋势。在盐胁迫下,渗透调节物质的积累作用是大米草对盐胁迫的主要响应过程,其体内的抗氧化保护酶在此过程中也发挥了重要的作用。     

低能氩离子注入对甜瓜幼苗抗氧化系统的影响

就低能氩离子注入对甜瓜幼苗抗氧化系统的影响进行研究,使用不同剂量的离子注入甜瓜种子,结果表明,不同剂量离子注入后伽师瓜、皇后品种的超氧化物歧化酶(SOD)分别在5×1016Ar /cm2、4×1016Ar /cm2剂量时酶活性最大,之后下降。抗坏血酸过氧化物酶(ASP)的活性的变化趋势与超氧化物歧化酶相似,分别在6×1016Ar /cm2、4×1016Ar /cm2剂量时酶活性最大。抗坏血酸和类黄酮的含量都有不同程度的上升,说明离子注入能诱导甜瓜幼苗抗氧化系统的生物合成。     

丛枝菌根真菌对盐胁迫下黄瓜幼苗渗透调节物质含量和抗氧化酶活性的影响

以盐敏感型黄瓜品种‘津春2号’为材料,研究了丛枝菌根真菌(AMF)对盐胁迫下黄瓜幼苗生长及叶片、根系中渗透调节物质含量和抗氧化酶活性的影响.结果表明:(1)在盐胁迫条件下,黄瓜幼苗生长受到明显抑制,其株高、地上部、地下部干鲜重均明显减小,同时体内可溶性蛋白、可溶性糖、脯氨酸和MDA含量,以及O2(÷)产生速率和SOD、POD、CAT活性均比对照显著升高.(2)盐胁迫下接种AMF可显著促进黄瓜植株的生长,进一步提高黄瓜幼苗体内可溶性蛋白、可溶性糖和脯氨酸含量及SOD、POD、CAT活性,而显著降低MDA含量和O2(÷)产生速率.研究表明,AMF可通过显著促进盐胁迫下黄瓜幼苗体内渗透调节物质积累和抗氧化酶活性提高,有效降低体内膜脂过氧化水平,从而缓解盐胁迫对植株的伤害,增强黄瓜幼苗对盐胁迫的耐性.     

菌紫质的Ser和Lys残基修饰对BR结构和功能的影响

用化学修饰研究了菌紫质（ＢＲ）的结构和功能的变化。用氮氧自由基分别对赖氨酸和丝氨酸进行修饰,研究结果表明在圆二色谱上（ＣＤ谱）,与天然紫膜样品比较,两种自由基分别修饰赖氨酸（Ｌｙｓ）和丝氨酸（Ｓｅｒ）残基２４小时后的ＣＤ谱中均只有负峰,分别在５９６ｎｍ和６０２ｎｍ,５３５ｎｍ的正峰已消失,７２小时后５３５ｎｍ的正峰部分地恢复,但１２０小时后均未见进一步恢复。与未修饰的紫膜相比,两种自由基修饰的紫膜在Ｒａｍａｎ光谱上观察到中间体Ｍ４１２的相对量要明显增加。本文对这二种化学修饰引起的ＢＲ结构和功能变化进行了初步讨论。     

Regeneration of intergeneric somatic hybrids by protoplast fusion between Onobrychis viciaefolia and Medicago sativa

Protoplast fusion was induced between sainfoin and alfalfa by an improved polyethyleneglycol (PEG) method. The intergeneric somatic calluses were selected based on complementation of hydroxyproline-resistance of sainfoin and hormone autonomy growth of alfalfa transformation cell line. 17 somatic hybrid plantlets were regenerat-ed. PEG could induce the tight agglutination of protoplasts. During diluting and washing process, cyclization of the linked membrane and formation of vesicle-like structures were observed, resulting in protoplast fusion. 5%-10% glycerol supplemented in the fusion inducing solution markedly increased the frequency of heterogeneous fusion. Better fusion results were obtained when mixed protoplast suspension was dripped in petri dishes in which PEG solution was previously placed. Chromosome number of regenerated hybrid buds varied from 30 to 60. The genome of hybrids in-cluded the small chromosome from sainfoin and two chromosomes with two clear constrictions from alfalfa. The hybrid     

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.