303 resultados para NaCl 7.5%


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由于近年来有害微生物的肆虐和人们防病抗菌意识的增强,社会对各种新型抗菌材料的需求越来越迫切。抗菌不锈钢是一种兼具良好机械和抗菌性能的新型功能材料,具有广泛的应用前景。开发和推广抗菌不锈钢,具有重要的经济和社会意义。 本文以中科院金属研究所研制的两种抗菌不锈钢为研究对象,对其抗菌性能和抗菌机理进行了研究,以期为抗菌不锈钢的深入研发和推广提供理论依据。 本文获得了如下主要结论: 1.采用覆膜法研究了抗菌不锈钢的抗菌广谱性,铁素体和奥氏体抗菌不锈钢对供试的17株菌(除产气肠杆菌外),均显示了较强的杀灭作用,证明其具有抗菌广谱性。两种材料对非孢子(或芽孢)产生菌的杀灭作用强于孢子(或芽孢)产生菌。但是,两种材料对产气肠杆菌均无杀灭作用。 2.考察了铁素体和奥氏体的杀菌率随时间和菌浓度的变化情况。两种材料分别在作用3h时和9h时,对菌体浓度为1×107CFU/mL的大肠杆菌(ATCC25922)的杀菌率均达到99.5%。对菌体浓度≤1×107CFU/mL的大肠杆菌在24h内均可全部杀灭。 3.随打磨次数的增加,抗菌率没有变化,表明打磨不影响铁素体和奥氏体抗菌不锈钢的抗菌性能;抗菌率不受温度的影响,0~37℃之间,未观察到抗菌率受温度变化的明显影响。 4.从抗菌不锈钢中溶出的铜在杀菌过程中可能起重要作用。铁素体和奥氏体抗菌不锈钢与添加了终浓度为1mmol/L的EDTA的菌液作用后,杀菌率分别降为46.8%和38.8%,因为EDTA络合了溶液中的金属离子,间接表明铜离子在杀菌过程中起重要作用。 5.两种抗菌不锈钢中O2-的产生速率分别为0.117 nmol•min-1•g-1和0.107nmol•min-1•g-1,显著高于普通不锈钢(0.062 nmol•min-1•g-1)。细胞膜不饱和脂肪酸过氧化的终产物丙二醛含量分别为1.96 nmol/g和1.93 nmol/g。显著高于普通对照的1.08 nmol/g,表明存在脂肪酸被氧化的现象。这些结果为抗菌过程中存在O2-的氧化杀菌作用提供了间接证据。 6.通过透射电镜和原子力显微镜观察,与抗菌不锈钢作用后的细胞外形多发生变化,细胞壁和细胞膜破裂,细胞内容物漏出,有的菌体完全溶解为碎片,显示两种不锈钢对细胞膜和细胞壁形态的显著影响。随作用时间延长,菌液中钾离子浓度亦显著升高,在3h时,分别达到2.57mg/L和2.79mg/L(普通对照为1.61mg/L)。 7.在巯基氧化实验中,添加终浓度为5 mmol/L的L-cys,作用8h,铁素体的抗菌率降为11.1%,薄层层析结果显示,半胱氨酸可能被氧化成胱氨酸,表明抗菌不锈钢可能对还原性酶具有氧化作用。 8.提取与抗菌不锈钢作用后菌的DNA,凝胶电泳观察并未出现smear现象。表明在本实验条件下尚不能检测到抗菌不锈钢对细菌遗传物质的氧化切割作用。 关键词: 抗菌材料 抗菌不锈钢 抗菌性能 抗菌机理 O2-

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根土生态界面的研究是一个全新的课题,其研究方法和测定技术是进行此项研究首先需要解决的问题。本文以长白山地区阔叶红松林的主要树种:红松(Pinus koraiensis)、核桃楸(Juglans mandshurica)、水曲柳(Fraxinus mandshurica)和紫椴(Tilia amurensis)为研究对象,对其研究方法和技术进行探索和试验,同时对红松幼苗根土生态界面及其过程进行了研究。对四种树种的三年生幼苗进行了根土生态界面环境面一侧一根际的pH值和氧化还原状况的原位显色,结果表明,红松和核桃楸的根际呈酸性(5.2 < pH < 6.0),水曲柳和紫椴的根际呈碱性(pH > 7.5),并由此推断出红松根系分泌质子的部位,主要表现在根尖以上4.5-8cm范围内。四种苗木根际的氧化还原状况均为氧化型。运用电子探针技术对红松幼苗根土生态界面进行定量的点分析,并依据界面中营养元素(N、P、K、Mg)的浓度梯度对根土生态界面进行刻画,结果表明,以N来刻画,其根土生态界面的范围是从根60μm到土40μm(以根表为分界线,分别向根组织方向和土壤方向测点),变动空间是100μm;以P刻画的根土生态界面的范围的从根40μm到土20μm,变动空间是60μm;以K刻画的根土生态界面的范围是从根30μm到土90μm,变动空间是120μm;以Mg来刻画,其根土生态界面的范围是从根20μm到土10μm,变动空间为30μm。应用根垫法的模拟培育装置对根土生态界面环境面一侧一根际的养分状况进行了研究,结果表明;随着培育过程的延续,营养元素的亏缺区增大,界面宽度增加;同一时间,同一处理,亏缺区的范围是N > K > P,表明其在土壤中的扩散的N > K > P,与已有的知识相吻合;红松幼苗对营养元素N、P、K的吸收均为对数型。从以上的试验结果,证明根垫法模拟培育装置在林木根际研究中是可行的,但还有有待改进的地方。根据以上的实验结果,对阔叶红松林的经营提出了几点对策性建议。

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农田生态系统是大气N_2O的重要排放源。因此,阐明其N_2O产生及排放机理并正确制定出减排对策是目前温室气体研究领域的主要目标之一。本文利用封闭式箱法技术首次对旱田生态系统(玉米、大豆和春小麦)N_2O通量进行了长期系统的连续观测。阐明了旱田N_2O产生的生物化学机理及植物在植物-土壤系统N_2O排放中的作用并进一步进行了减少旱田N_2O排放的措施研究。为农业和环境的可持续发展提供了科学依据及有效的技术措施。旱田作物的N_2O排放有明显的日变化和季节变化规律,大量的N_2O排放发生在作物的生育期内且不同作物的N_2O排放量也各异。玉米-土壤系统、大豆-土壤系统及春小麦-土壤系统N_2O通量范围分别为-7.5~466.50ugN_2O-Nm~(-2)h~(-1)、-12.90~420.00ugN_2O-Nm~(-2)h~(-1)和-6.00~29.60ugN_2O-Nm~(-2)h~(-1),平均通量分别为63.75ugN_2O-Nm~(-2)h~(-1)、27.05ugN_2O-Nm~(-2)h~(-1)和9.10ugN_2O-Nm~(-2)h~(-1)。从环境因素与N_2O排放的关系上分析,得出以下重要结果。实验室模拟培养条件下,温度、pH对N_2O排放产生很大影响。而在大田自然环境条件下,由于在作物生育期内土壤pH及温度的变化范围都不是很大,因此对N_2O的排放没有产生显著影响;N_2O排放与土壤含水量关系密切,随含水量的变化而变化。表明土壤含水量是影响N_2O排放的重要因素;利用乙炔抑制技术,研究了大田N_2O产生途径,发现在低土壤含水量情况下,N_2O主要产生于土壤微生物的硝化过程。在高含水量情况下,N_2O主要来自于反硝化过程。而在中等含水量情况下,硝化和反硝化作用都是N_2O产生的主要途径。植物排放N_2O以前一直被忽略,未受到应有的重视。其实植物在N_2O排放中占有比较大的份额。试验中发现,玉米植株在其整个生育期内都能排放N_2O且根系对土壤N_2O产生起促进作用。与肥料(尿素)相比,无肥大田的玉米植株对N_2O排放的贡献占17.3%,而尿素占82.7%。土壤中N转化的生物化学过程都是在酶的参与下进行的。土壤中酶的活性变化反映了土壤中进行的各种生物化学过程的强度和方向。对土壤反硝化酶-硝酸还原酶(NR)、亚硝酸还原酶(NiR)和羟胺还原酶(HyR)的研究结果表明,三种还原酶都有明显的季节变化规律并受土壤水分含量及施肥的影响。研究三种反硝化还原酶活性变化与土壤含水量及N_2O排放之间的关系后指出,通过测定它们在土壤中的活性变化也许可以作为区分旱田土壤N_2O产生途径(硝化、异化反硝化、同化反硝化)的指标之一。基于上述阐明的旱田N_2O产生机理,进一步通过改进肥料配方的方法深入进入了减少旱田N_2O排放的措施研究。结果表明,缓释尿素(尿素+氢醌+双氰胺)和长效碳铵(碳铵+双氰胺)不仅能明显增加作物产量,而且还能明显减少N_2O的排放,有着明显的经济和环境双重效益。

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对辽西半干旱区褐土农田施用几种保水剂的效果进行了室内模拟和田间试验研究.观测了保水剂包衣和沟施对春小麦出苗、土壤水分含量及产量的影响,对使用保水剂的适宜浓度、效果、经济效益进行了评价,并对保水剂促进出苗的机理和田间保水机制进行了探讨.结果表明,保水剂包衣能够加快种子吸水过程,促进春小麦萌发出苗,出苗期提前1~2天,出苗率提高6.5%~11.5%,增产7.5%~12.7%,投入产出比为1:7.保水剂包衣的适宜浓度为1%,浓度过大(≥5%),保水剂层过厚,会影响种子呼吸和水分通过,不利于出苗,出苗率和产量分别提高5%和10%以上.保水剂沟施,可提高土壤持水能力,0~30cm的土壤水分含量,提高了1个百分点.保水剂沟施处理,水分利用效率可提高0.7~2.0kg·mm<'-1>·hm<'-2>,提高幅度为6.7%~18.5%.研究发现,保水剂田间保水效果,与土壤含水量有关,土壤水分低于毛管断裂含水量时,保水剂对蒸发速率影响很小.

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本文结合野外调查和森林经营资料,以GIS为核心技术,综合空间分析与多种统计方法,研究了采伐干扰下白河林业局森林资源的动态变化,并使用FoREsTA严森林资源经营管理决策支持系统进行模拟,对多种采伐方案进行了系统的研究。该研究对指导整个长白山区的采伐经营,保护森林资源,实现森林生态系统科学经营与景观管理具有重要的理论意义。主要结论如下:①采伐活动在一定时间内改变植物种群的生态位,伐后10年7个树种的生态位宽度升高并逐渐高出原始林的生态位宽度。其生态位重叠从采伐后至伐后5年降低,以后逐渐升高,20年时与原始林基本相同;伐后灌木种群的生态位宽度与生态位重叠都增大,伐后巧年逐渐降低,伐后20年与原始林基本相同。②采伐强度影响植物群落的多样性,10%采伐强度采伐干扰的乔木的多样性伐后先降低再逐渐增加,20%和30%采伐强度采伐干扰的乔木的多样性随时间变化没有明显的规律;10%与20%采伐强度的灌木的多样性伐后先升高再降低,30%采伐强度的灌木多样性伐后先减少再增加;在所有采伐干扰中,草本层的多样性自伐后5年起逐渐升高,伐后20年,多样性基本趋于稳定。与原始林的多样性相比,10%的采伐强度可以增加乔木、灌木和草本的多样性,20%采伐强度增加了灌木的多样性。③经过13年经营,白河林业局森林林龄、单位蓄积和郁闭度较高等级的森林面积减少,较低等级的森林面积增加。林分质量下降。④经过13年,林业用地景观更加破碎,复杂程度降低,人类的干扰程度增强;基于景观划分的经营类型出现较大差异。⑤利用FoREsTA严决策支持系统进行采伐决策时,应该根据资源分布选择不同的采伐方案。从景观经营的角度,森林景观空间结构方案以及森林景观空间结构方案与实际木材采伐方案相组合后的方案更具有参考价值。

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为了研究长白山北坡针叶林下土壤淋洗液的化学性质及土壤特性。我们于1987年6-9月,在红松云冷杉林。岳桦云冷杉林标准地,收集了大气降水,林内降水及土壤淋洗液,进行化学分析。结果表明:在红松云冷杉林标准地大气降水经过林冠后产生酸化作用。在红松云冷杉林和岳桦云冷杉林标准地,通过A_0层淋洗液进入土壤A_1层的养分元素(公斤/公顷)为:K 7.4-11.0, Ca 5.7-5.8, Mg 1.1-1.2,有机碳120.4-156.1,全氮1.9-3.4, SO_4-S 1.8-3.6。 A_0+A_1层养分元素的淋失量(公斤/公顷)为:K 1.2-1.6, Ca 2.2-4.6, Mg 0.5-0.9,有机碳35.4-43.9,全氮0.6-0.7, SO_4-S 1.2-2.7。A_0层淋洗液酸度大(pH5.2-5.6)。有机酸含量高(有机碳46-62mg/1)。Fe、Al、Si均从A_1层淋洗下来,并在其下的淀积层(B)淀积。因此,本区针叶林下土壤具有灰化过程的典型特征。土壤分析结果表明:长白山北坡暗针叶带土壤,具有灰化过程,其中杜香落叶松林下土壤具有明显的灰土淀积层,在分类上属灰土。

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Without introducing concentration quenching phenomenon, a few wt% of Tb3+ and Yb3+ ions were doped into a group of easily-fiberized tellurite glasses characterized by loose polyhedron structures and rich interstitial positions. Intense green upconversion emission from Tb3+ ions centered at 539 nm due to transition 5D4→7F5 was observed by direct excitation of Yb3+ ions with a laser diode at 976 nm. Optimizing the concentration ratio of Tb3+/Yb3+, a tellurite glass with composition of 80TeO2-10ZnO-10Na2O (mol%)+1.0wt% Tb2O3+3.0wt% Yb2O3 was found to present the highest green light intensity and therefore is especially suitable for efficient green fiber laser development.

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针对30°楔角的驻定斜爆轰特性,选择在临界爆轰马赫数附近6.8、7.0与7.5等3种不同马赫数来流状态进行数值分析. 在马赫数为6.8、7.0状态下,在斜激波(oblique shock wave,OSW)、斜爆轰波(oblique detonation wave,ODW)与爆燃波交汇处形成的三波点后形成一道激波,在楔面上反射,并透过接触间断面与爆轰波阵面产生的横波相互作用,使得下游流场发生扰动,形成不规则的胞格结构. 斜爆轰波阵面产生的横波呈现上游单向传播与下游双向传播同时并存的现象,对斜爆轰的稳定性产生了影响

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本论文对滇金足草(Goldfussia yunnanensis)、凋缨菊(Camchaya loloana)和长喙吴萸(Evodia vestia)的化学成分进行了研究,通过色谱分离得到40个化合物。主要基于波谱数据鉴定了它们的结构,其中10个为新化合物。 1.从滇金足草地上枝叶的95%乙醇提取物中共分离鉴定了16个化合物:泽漆内酯A(1)、18-羟基泽漆内酯A(2)、18-氧代泽漆内酯A(3)、18-羟基-3-O-β-D-吡喃葡萄糖-泽漆内酯A(4)、3-O-β-D-吡喃葡萄糖-泽漆内酯A(5)、3-O-β-D-吡喃半乳糖-泽漆内酯A(6)、6-E-肉桂酰哈巴俄苷(7)、E-哈巴俄苷(8)、5,6-异亚丙二氧基哈巴俄苷(9)、β-谷甾醇(10)、β-胡萝卜苷(11)、齐墩果酸(12)、肉桂酸(13)、麦角固醇(14)、硬脂酸(15)和丁二酸(16)。其中2-7为新化合物。5,6-异亚丙二氧基哈巴俄苷(9)以人工产物形式得到。 2.从凋缨菊地上枝叶的95%乙醇提取物中分离并鉴定了13个化合物:凋缨菊内酯A~C (17-19)、1β-乙酰基凋缨菊内酯C(20)、b-谷甾醇(10)、β-胡萝卜苷(11)、羽扇豆醇(21)、桦木醇(22)、桦木酸(23)、芥子醇(24)、紫丁香苷(25)、咖啡酸(26)和熊果酸(27)。其中化合物17-20为桉叶烷内酯类新化合物。化合物17、18、20对细胞株HepG2的GI50依次为7.80、7.08、4.99 µg/mL。 3.从长喙吴萸(E. vestia)地上枝叶的95%乙醇提取物中分离并鉴定了13个化合物:佛手内酯(28)、花椒毒素(29)、异茴芹内酯(30)、七叶内酯(31)、东莨宕素(32)、瑞香素(33)、异紫花前胡内酯(34)、茵芋碱(35)、山刈碱(36)、白鲜碱(37)、黄柏酮(38)、柠檬苦素(39)和对羟基苯甲醛(40)。 4.综述了1990—2007年期间从菊科植物中发现的桉叶烷-12,6内酯的化学结构、生物活性、生物转化及化学合成方面的研究进展。 Phytochemical investigation on Goldfussia yunnanensis, Camchaya loloana, and Evodia vestia, led to the isolation of 40 compounds, 10 of which were new ones. 1. Six new compounds were isolation from 95% ethanolic extract of the aerial parts of G. yunnanensis, and identified as 18-hydroxyhelioscopinolide A (2), 18-oxohelioscopinolide A (3), 18-hydroxy-3-O-β-D-glucopyranosylhelioscopinolide A (4), 3-O-β-D-glucopyranosylhelioscopinolide A (5),3-O-β-D-Galactopyranosyl helioscopinolide A (6), 6-O-trans-cinnamoyl E-harpagoside (7). The known compounds isolated were helioscopinolide A (1), E-harpagoside A (8), 5,6-isopropylidene E-harpagoside A (9), β-sitosterol (10), β-daucosterol (11), oleanolic acid (12), cinnamic acid (13), ergosterol (14), stearic acid (15) and succinic acid (16). Compound 9 was an artifact. 2. Four new compounds, loloanolides A – C (17 - 19) and 1β-acetoxy-loloanolide C (20), were isolation from 95% ethanolic extract of the aerial parts of C. loloana. The known ones were β-sitosterol (10), β-daucosterol (11), lupeol (21), betulin (22), betulinic acid (23), sinapyl (24), syringin (25), caffeic acid (26) and ursolic acid (27). The GI50 values of compounds 17, 18 and 20 to HepG2 cell line were 7.80, 7.08 and 4.99 µg/mL, respectively. 3. Thirteen were isolated from 95% ethanolic extract of the aerial parts of E. vestia for the first time. They were determined to be bergapten (28), xanthotoxin (29), isopimpinellin (30), esculetin (31), scopoletin (32), daphnetin (33), marmesin (34), skimmianine (35), confusameline (36), dictamine (37), obacunone (38), limonin (39) and p-hydroxy phenyl aldehyde (40). 4. The structures, biological activities, biotransformation and chemical syntheses of eudesmane-12, 6-olides from the Asteraceae during 1990-2007 were reviewed.

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近十年,植物群体遗传学的研究飞速发展,然而与海拔相关的植物群体遗传结构和遗传变异研究却相对较少。到目前为止,还不清楚遗传变异与海拔之间是否有一个通用的格局。在山区,各种生态因子,如温度、降水、降雪、紫外线辐射强度以及土壤成分都随海拔梯度急剧变化,造成了即使在一个小的空间区域,植被类型变化显著,这种高山环境的异质性和复杂性为我们研究植物群体遗传结构和分化提供了方便。沙棘(Hippophea)属于胡颓子科(Elaeagnaceae)为多年生落叶灌木或乔木,雌雄异株,天然种群分布极为广泛。中国沙棘(H. rhamnoides subsp. sinensis)是沙棘属植物中分布较广的一个亚种,种内形态变异非常丰富,加之其具有独特的繁育系统和广泛的生态地理分布,是研究沙棘属植物遗传变异和系统分化的理想材料。本文从1,800 m 到3,400 m 分5 个海拔梯度进行取样,用RAPD 和cpSSR 分子标记研究了卧龙自然保护区中国沙棘天然群体的遗传结构和遗传变异。5 个取样群体依次标记为A、B、C、D 和E,它们分别代表分布在海拔1,800,2,200,2,600,3,000 和3,400 m 的5 个天然群体。RAPD实验用11 条寡核苷酸引物,扩增得到151 个重复性好的位点,其中143 个多态位点,多态率达94.7%。在5 个沙棘群体中,总遗传多样性值(HT)为0.289,B群体内的遗传多样性值为0.315,这完全符合沙棘这种多年生、远交的木本植物具有高遗传变异的特性。5 个群体内遗传多样性随海拔升高呈低-高-低变异趋势,在2,200 m海拔处的B群体遗传多样性达最大值0.315,3,400 m海拔处的E群体则表现最小仅0.098。5 个群体间的遗传分化值GST=0.406,也即是说有40.6%的遗传变异存在于群体间,1,800 m海拔处的A群体与其它群体的明显分离是造成群体间遗传分化大的原因。UPGMA聚类图和PCoA散点图进一步确证了5 个群体间的关系和所有个体间的关系。最后,经过Mantel检测,遗传距离与海拔表现了明显的相关性(r = 0.646, P = 0.011)。cpSSR 实验中,经过对24 对cpSSR 通用引物筛选,11 对引物能扩增出特异性条带,只有2 对引物(ccmp2 和ARCP4)呈现多态性。4 个等位基因共组合出4 种单倍型,单倍型Ⅰ出现在A 群体的所有个体和B 群体的8 个个体中,C、D、E 三个群体均不含有,而单倍型Ⅱ出现在C、D、E 三个群体的所有个体及B 群体的18 个个体中,A 群体不含有。另外两种单倍型Ⅲ和Ⅳ为稀有类型,仅B 群体中的4 个个体拥有。这种单倍型分布模式和TFPGA 群体聚类图揭示了,C、D、E 群体可能来源于同一祖先种,而A 群体却是由另一祖先种发展起来的,B 群体则兼具了这两种起源种的信息,这可能是因为在历史上的某一时期,在中国沙棘群体高山分化的过程中,B 群体处某个或者某些个体发生了基因突变,具备了适应高海拔环境的能力,产生了高海拔沙棘群体的祖先种。 In recent ten years, studies about population genetics of plants developed rapidly,whereas their genetic structure and genetic variation along altitudinal gradients have beenstudied relatively little. So far, it is uncleared whether there is a common pattern betweengenetic variation and altitudinal gradients. In the mountain environments, importantecological factors, e.g., temperature, rainfall, snowfall, ultraviolet radiation and soil substratesetc., change rapidly with altitudes, which cause the vegetation distribution varying typically,even on a small spatial scale. The mountain environments, which are heterogeneous andcomplex, facilitate and offer a good opportunity to characterize population genetic structureand population differentiation.The species of the genus Hippophae L. (Elaeagnaceae) are perennial deciduous shrubs ortrees, which are dioecious, wind-pollinated pioneer plants. The natural genus has a widedistribution extending from Northern Europe through Central Europe and Central Asia toChina. According to the latest taxonomy, the genus Hippophae is divided into six species and12 subspecies. The subspecies H. rhamnoides ssp. sinensis shows significant morphologicalvariations, large geographic range and dominantly outcrossing mating system. Thesecharacteristics of the subspecies are favourable to elucidate genetic variation and systemevolution. To estimate genetic variation and genetic structure of H. rhamnoides ssp. sinensisat different altitudes, we surveyed five natural populations in the Wolong Natural Reserve at altitudes ranging from 1,800 to 3,400 m above sea level (a.s.l.) using random amplifiedpolymorphic DNA markers (RAPDs) and cpSSR molecular methods. The five populations A,B, C, D, and E correspond to the altitudes 1,800, 2,200, 2,600, 3,000 and 3,400 m,respectively.Based on 11 decamer primers, a total of 151 reproducible DNA loci were yielded, ofwhich 143 were polymorphic and the percentage of polymorphic loci equaled 94.7%. Amongthe five populations investigated, the total gene diversity (HT) and gene diversity within population B equaled 0.289 and 0.315, respectively, which are modest for a subspecies of H.rhamnoides, which is an outcrossing, long-lived, woody plant. The amount of geneticvariation within populations varied from 0.098 within population E (3,400 m a.s.l.) to 0.315within population B (2,200 m a.s.l.). The coefficient of gene differentiation (GST) amongpopulations equaled 0.406 and revealed that 40.6% of the genetic variance existed amongpopulations and 59.4% within populations. The population A (1,800 m a.s.l.) differed greatlyfrom the other four populations, which contributes to high genetic differentiation. A UPGMAcluster analysis and principal coordinate analyses based on Nei's genetic distances furthercorroborated the relationships among the five populations and all the sampling individuals,respectively. Mantel tests detected a significant correlation between genetic distances andaltitudinal gradients (r = 0.646, P = 0.011).Eleven of the original 24 cpSSR primer pairs tested produced good PCR products, onlytwo (ccmp2 and ARCP4) of which were polymorphic. Four total length variants (alleles) werecombined resulting in 4 haplotypes. The haplotype was present in all individuals of Ⅰpopulation A and 8 individuals of populations B, the other three populations (C, D and Epopulations) did not share. The haplotype was present in all individuals of populations C, D Ⅱand E and 18 individuals of populations B, population A did not share. The other twohaplotypes and were rare haplotypes, which were only shared in 4 individuals of Ⅲ Ⅳpopulation B. The distribution of haplotypes and TFPGA population clustering map showedthat the populations C, D and E might be origined from one ancestor seed and population Amight be from another, whereas population B owned information of the two ancestor seeds. Itwas because that gene mutation within some individual or seed in the location of population Bwas likely to happen in the history of H. rhamnoides, which was the original ancestor of thehigh-altitude populations.

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棘蛙族(Tribe Paini)隶两栖纲(Amphibia)、无尾目(Anura)、蛙科(Ranidae)、叉舌蛙亚科(Dicroglossinae),由棘蛙属(Paa)、倭蛙属(Nanorana) 和沙巴蛙属(Chaparana)构成(Dubois,1992)。由于特殊的形态特征和染色体核型,棘蛙族受到国内外学者的广泛重视和研究,但是到目前为止,棘蛙族的系统发育关系尚未明晰,族下属种的分类和归属问题还有待进一步研究和新的证据出现。本文通过光学显微镜、电子显微镜和石蜡切片对棘蛙族10 物种的精子和精巢进行研究,旨在了解棘蛙族精子的形态、量度、超微结构特征及不同季节精巢结构的变化规律,同时为棘蛙族的系统研究提供新的依据,也为棘蛙族濒危物种的保护和经济物种的繁殖提供基础资料。研究结果表明:棘蛙族各属物种精子的形态基本相似,精子整体呈线形,由头部、中片和尾部构成。精子头部呈长条状,顶体呈锥状,位于头部顶端并向前伸出,中片较长,尾部波动弯曲。棘蛙族各属物种精子量度差异较大,将各属物种精子头部、中片、尾部、头宽、尾宽的量度数据进行聚类分析,结果表明棘蛙族10 物种可分为三类:第一类包括棘侧蛙、合江棘蛙、小棘蛙、棘腹蛙和棘胸蛙,特点是精子较短,全长在72.6~103.35µm 之间;第二类包括倭蛙、高山倭蛙、腹斑倭蛙,特点是精子较长,全长在107.74~129.75µm 之间;第三类包括隆肛蛙和双团棘胸蛙,特点是精子最长,全长在145.89~165.84µm 之间。棘蛙族各属精子超微结构基本相似:精子头部由顶体、细胞核构成;中片由中心粒、线粒体构成;尾部由单根轴丝构成。精子顶体横切呈圆环状,细胞核电子密度高;线粒体为卵圆形,呈环状围绕轴丝排列,线粒体数目较多,约30层;尾部轴丝为典型的9+2结构,即由2根中央微管和9对外周微管组成。不同季节的倭蛙精巢结构变化表明倭蛙精巢每年只有一个生精周期,生精周期始于7 月,繁殖季节从5 月到6 月,生精高峰期为9 月;根据倭蛙不同季节精巢结构的变化,可将生精周期分为3 个阶段:第一阶段从7 月到9 月,为精子形成期;第二阶段从10 月到翌年4 月,为精子的贮存阶段,也即倭蛙的冬眠期;第三阶段从5 月到6 月,为精子的排放阶段,即倭蛙的繁殖期。不同季节的隆肛蛙精巢结构变化表明5 月为隆肛蛙的繁殖高峰期。根据棘蛙族各属精子的形态、量度和超微结构特征,结合已有的棘蛙族形态学、生态学、染色体核型及系统学研究成果,本文认为:1.基于精子数据对棘蛙族的划分和基于形态学及分子系统学数据对棘蛙族的划分均有相同之处,精子形态结构可为棘蛙族的系统研究提供新的证据。2. 棘蛙族各属精子的形态、量度及超微结构不仅与蛙科其他属种有明显差异,而且在无尾类中也较为特殊,精子学研究结果支持将棘蛙族从蛙科中分离出来,归隶于叉舌蛙科的叉舌蛙亚科的系统学修正。3. 精子的顶体、细胞核、中片的形态结构及量度可作为蛙科的分类指标。On the base of unique morphological and kyrotype characters, Dubois(1992)recognized three genera Paa, Narnorana, Chaparana as tribe Paini, which is amember of Dicroglossinae, Ranidae. In present study, the sperm shape, size andultrastructure of 10 paini species were investigated through the light and electronmicroscope, and testis structure of N. pleskei and F. quadrana was also studied. Wesuppose this study could offer some spermatological evidence to phylogeny andreproduction study of tribe Paini. The results were as follows:The sperm shape of tribe paini is homologically similar, the spermatozoa arefiliform, composed of elongate head, long mid-piece and waved tail. The acrosome isapically associated with the nucleus and extend anteriorly.The sperm length of tribe paini differ remarkably among genera. Cluster for thelength of sperm head, mid-piece, tail, total length, head-width, tail-width of ten painifrogs indicated the 10 species could be separated into three groups: GroupⅠcontainsP. shini, P. robertingeri, P. spinosa, P. exilispinosa, P. boulengeri, the spermatozoa ischaracterized with short in total length, ranging from 72.6µm to 103.35µm; GroupⅡcontains N. pleskei, N. parkeri, N. ventripunctata, the spermatozoa ischaracterized with relatively long in total length, ranging from 107.74µm to129.75µm; Group Ⅲ contains F. quadrana and P. yunnanensis, the spermatozoa is characterized with longest in total length, ranging from 145.89µm to 165.84µm. thethree groups based on spermatological data is partially match the classification basedon morphological and molecular data.The ultrastructure of spermatozoa in tribe paini is also basic similar, includingacrosome vescile, nuleus of the head proper, centriole, mitochondriol of themid-pieces, axoneme of the tail. The acrosome vescle is circle in TEM transversesection, the density of nucleus is high; The mitochondrions is oval, surrounding theaxial filament with about 30 layers of mitochondria; The axoneme has the typical 9+2pattern of microtubules.The seasonal changes in testis of N. pleskei indicates it has only onespermatogenesis circle, which begin in July, the reproduction season is from May toJune, the spermatogenesis is active in September. On the base of seasonal changes intestis, the spermatogenesis circle can be separated into three stages: In stageⅠfromJuly to September, spermatids are formed; In stage Ⅱ from October to April next year,the spermatozoa are stored in testis,which is the hibernated period; In stage Ⅲ fromMay to June, mature spermatozoa were released from the testis, which is thereproduction season of N. pleskei. As to F. quadrana, reproduction is active in May.With the previous study of morphology, ecology, karyotypes and phylogenyresearch of tribe Paini, the spermatological data in present study suggests:1. The spermatological classification of tribe paini is partially consistant with themorphological and molecular classification respectively.2.The sperm morphology and ultrustructure of tribe paini is unique not only inthe family Ranida but also in Anura, which suggest the tribe paini is monophyletic andmight be transfered from the family Ranida to the family Dicroglossidae based onmolecular evidence.3. The acrosome, nuleus, shape, length and ultrastructure of mid-piece can beused as an alternative taxonomic character in Anura.

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从成都市洪河垃圾场采样分离到三株嗜热纤维素分解细菌,均为严格厌氧的革兰氏阴性杆菌,有较高的纤维素降解活性,能直接转化为纤维素产酒精。其中TCl菌株为周生鞭毛运动,不产生芽孢,大小为0.9×2.4~5.4um,表明菌落为白色,边缘整齐的圆形,最适温度在55℃,最适PH大约7.0,发酵纤维素或纤维而糖产生乙酸、丁酸。该菌属于拟杆菌料(Bacteroidaceae),不能归入已有的任何一属,很可能是一个新的属。TC3和TC4为单端丛生鞭毛运动,大小为0.6×2.4~15um,形成卵圆形或圆形的端生芽孢,使菌体膨大。TC3的菌落为灰白色、透镜状,TC4的菌落为黄色,透镜状,TC4在液体培养基中产生非水溶性黄色素。最适温度均为55℃,最适PH值TC3为8.0,TC4为7.5。TC3、TC4属于梭菌属,与所有已报道的同类菌株均有显著差异,因此认为它们可能是梭菌属 (clostridium)中的新种。