中国特有濒危植物崖柏的木材结构研究

应用光学显微镜和扫描电子显微镜,首次对中国特有濒危植物崖柏的木材结构进行了研究,其主要特征为:生长轮中早材至晚材急变,晚材带较窄;轴向管胞较短,平均长度1.61±0.22mm(早材管胞)至1.74±0.26mm(晚材管胞),具缘纹孔单列,在纹孔缘外表面及其周围偶见少量稀疏瘤状物;交叉场纹孔为杉木型,2～6(8)个;木射线单列,高1～11(2～5)个细胞,每平方毫米具65～70条木射线,端壁节状加厚和凹痕均较明显;木薄壁组织细胞多分布在晚材带中,端壁节状加厚略明显。崖柏与该属的木材结构特征基本相符。在讨论中还与崖柏属其余4个种的木材结构特征作了详细比较。     

17年生邓恩桉两个种源木材密度与干缩性研究

通过对邓恩桉两个种源木材基本密度和在湿、气、全干状态下的径、弦向尺寸的测定,研究了不同树干位置的基本密度和干缩率的变异规律,并运用加工工艺中减小木材皱缩和开裂措施(蒸汽调湿处理方法)探索皱缩开裂缺陷的恢复性能。结果表明:1)邓恩桉种源100(0.5265 g/cm³)的木材基本密度小于种源98(0.5360 g/cm³);2)木材基本密度在树干纵向呈波浪式变化,在横向边材显著大于心材;3)木材干缩率在纵向随高度的增加而减小,在横向边材大于心材,且弦向干缩率均为径向的1~3倍;4)经喷蒸调湿处理后,木材开裂程度减轻,且径向和弦向皱缩恢复率分别为0.4%、3.3%;5)木材基本密度与气干弦向干缩率存在极显著负相关(r=-0.313),并建立了气干干缩率与全干干缩率的回归模型。     

两种木香型天然香料的化学成分

杉木（Ｃｕｎｍｉｎｇｈａｍｉａｌａｎｃｅｏｌａｔａ（Ｌａｍｂ．）Ｈｏｏｋ）和圆柏（Ｓａｂｉｎａｃｈｉｎｅｎｓｉｓ（Ｌｉｎｎ．）Ａｎｔ．）分别为杉科和柏科的乔木。两种精油样品采自本所栽培植物的心材经蒸馏而得,其得率分别为：杉木油０５９０％,圆柏油０?..     

脓毒血症大鼠心肌II型磷脂酶A_2活性变化及其调控

观察了脓毒血症大鼠心肌ＩＩ型ＰＬＡ２ 活性、蛋白质含量及其ｍ ＲＮＡ 的变化。结果发现, 脓毒血症早期与晚期心肌ＩＩ型ＰＬＡ２ 活性较对照组分别降低２５ ．０ ％ （Ｐ ＜ ０ ．０５）及增高４７．６ ％ （Ｐ ＜ ０ ．０１）,ＩＩ型ＰＬＡ２ 蛋白质含量分别降低２７．０％ 及增高４８ ．０ ％（ 均Ｐ ＜ ０ ．０１）; 心肌ＩＩ型ＰＬＡ２ ｍ ＲＮＡ合成率与含量呈现类似的双相变化, 在脓毒血症早、晚期ｍＲＮＡ 合成率分别降低４５．０％ 和升高７０．０ ％ （均Ｐ ＜ ０ ．０１）,ｍＲＮＡ含量分别降低３４．１ ％ 和增加１５７ ．０％ （均Ｐ＜ ０ ．０１） 。脓毒血症早、晚期心脏ＩＩ型ＰＬＡ２ ｍ ＲＮＡ半衰期无显著变化（Ｐ ＞ ０．０５） 。实验结果表明大鼠脓毒血症发生过程中心肌ＩＩ型ＰＬＡ２ 活性呈现出先下降后升高的变化, 这一变化受其ｍＲＮＡ 转录水平的调节。     

脓毒血症大鼠心肌Ⅱ型磷脂酶A2活性变化及其调控

观察了脓毒血症大鼠心肌ＩＩ型ＰＬＡ２活性,蛋白质含量及其ｍＲＮＡ的变化,结果发现,脓毒血症早期为晚期心肌ＩＩ型ＰＬＡ２活性较对照组分别降低２５．０％（Ｐ〈０．０５）及增高４７．６％（Ｐ〈０．０１）,ＩＩ型ＰＬＡ２蛋白质含量分别降低了２７．０％及增高４８．０％（均Ｐ〈０．０１）,心肌ＩＩ型ＰＬＡ２ｍＲＮＡ合成率与含量呈现类似的双相变化,在脓毒血症早,晚期ｍＲＮＡ合成率分别降低４５．０％和升高７０．０     

冻干麻疹减毒活疫苗残余水分影响因素的探讨

影响冻干制品残余水分的因素很多,但西林瓶胶塞的含水量是其关键因素。使用经干烤工艺处理和未干烤处理的药用溴丁基胶塞进行麻疹减毒活疫苗冻干试验,结果显示,用未经干烤工艺处理及处理的药用溴丁基胶塞冻干的麻疹减毒活疫苗,存储18个月后,水分上升的平均值分别为2.03%和0.08%,经单一因素的方差分析,两者有统计学意义(P0.01)。证明经处理的药用溴丁基胶塞,对保持麻疹减毒活疫苗在存储期内的残余水分稳定作用效果明显。     

花蔺和黄花蔺居群遗传结构比较研究

采用垂直板型聚丙烯酰胺凝胶电泳技术,分别通过１９和２１个等位酶位点测定了花蔺３个居群和黄花蔺４个居群的遗传结构与基因流。两类群都维持较高水平的遗传多样性。花蔺居群期望杂合度、固定指数、异交率和遗传分化分别为０．１４４、０．１７４、９４．０％和０．２００,显示出异交繁育系统类型。黄花蔺居群期望杂合度、固定指数、异交率和遗传分化分别为０．０７６、０．４１５、５８．５％和０．３９１。表明其异交＋自交的敏     

日粮添加塞曼特罗（CIM）对大鼠生长胴体组成及GH水平的影响

选用２４只２月龄ＳＤ处女鼠配对分组,实验组日粮添加１０μｇ／ｇ塞曼特罗（ＣＩＭ）,试验期３０天。与对照组比较,ＣＩＭ显著提高大鼠生长速度（２７．３０％,Ｐ＜０．０１）和胴体比率,降低腰胁部脂肪重,提高腓肠肌、比目鱼肌和趾浅屈肌的鲜重和ＲＮＡ合量及ＰＮＡ／ＤＮＡ值,同时提高大鼠垂体和血清ＧＨ水平分别达３６．７０％（Ｐ＜０．０１）和２３．７７％（Ｐ＜０．０５）,降低血清脲氮含量。表明ＣＩＭ可显著促进大鼠生长,降低体脂含量,促进肌肉肥大,促进蛋白沉积。其作用机理可能还与其促进ＧＨ的合成和分泌有关。     

小偃麦花粉苗染色体加倍技术及其影响因素的研究

小偃麦花粉苗染色体加倍技术,采用下列四项综合措施,基本能使被处理花粉苗获得纯合十倍中体植株：（１）用０．０５％秋水仙碱＋２％ＤＭＳＯ溶液浸根、注射生长点各一次,其成活率和加倍率为８０．０％和８７．５％;（２）对苗少、分蘖少单株将药液就地注射正在生长的植株生长点内,加倍率为５０．０％,它是方法（１）的辅助和补充;（３）分蘖期将单株分割成若干分株参入处理,有利提高成活率和成功率;（４）适时偏早加倍,有     

三种温带树种树干储存水对蒸腾的贡献

树干储存水在协调叶片水分和碳平衡、维持树木水分收支平衡中起着重要作用。以无孔材红松(Pinus koraiensis)、散孔材山杨(Populus davidiana)和环孔材蒙古栎(Quercus mongolica)为对象, 于2010年8月中旬至9月末(生长季后期)测定其冠基和干基树干液流通量以及树干储存水的日变化过程, 量化分析树干储存水对日蒸腾量的贡献及其生物影响因子。结果表明: 冠基的液流比干基启动得早, 而且两者在一天中存在显著的时滞。树干储存水的日进程总体上可分为: 完全释放、以释放为主补充为辅、以补充为主释放为辅、饱和稳定等4个阶段, 但每个阶段的持续时间和变化格局随树种而变。红松的树干储存水在一天内表现出两个释放-补充周期, 而两种阔叶树种均只经历了一次释放-补充过程。在测定时段内红松、山杨、蒙古栎标准化到平均木(边材体积为0.29 m³)的树干储存水释放量分别为: (3.4 ± 1.5)、(2.4 ± 0.6)和(1.5 ± 0.4) kg·d ^-1, 分别占日蒸腾量的18.9%、17.1%和8.8%。树干储存水释放量与日蒸腾量呈显著的指数函数关系, 而与干基的边材面积和树高呈正相关关系。该研究突显了树木大小(树高和边材面积)和材性特征对树干储存水释放量及其对蒸腾量贡献的重要影响。     

Effect of Different Positions of Bordered Pit Torus in Yezo Spruce on Its Permeability

The green wood of yezo species (Picea jezoensis var. komarovii (V. Vassil.) Cheng et L. K. Fu) was treated with air drying and ethanol exchange drying and by soaking the air-dried wood in water followed by ethanol change drying. The results showed that the proportion of aspirated pits in the respective earlywood and latewood of the air-dried sapwood was increased to 99% and 81%, while that of heartwood was also as high as 97% and 86% because most of the bordered pits were aspirated at its green state. The permeability of air-dried sapwood and heartwood was as low as 0.114 and 0.045 darcy respectively. The proportion of aspirated pits in the earlywood and latewood of sapwood after ethanol exchange drying was very low (8% and 17% respectively), whereas that of heartwood was very high (97% and 86% respectively) since most of the pits in it were aspirated at its green state, so the ethanol exchange drying failed to prevent pit aspiration. The permeability of sapwood and heartwood after ethanol exchange drying was 11.713 and 0.074 darcy respectivly, which was increased 101.5 times and 62.0% over the permeability at air-dried state. t-test showed that the difference of permeability of ethanol exchange drying versus air drying for sapwood was very significant at the level of 0.1%, but was not significant for heartwood. The proportion of aspirated pits in earlywood and latewood of air-dried sapwood and heartwood after soaking in water followed by ethanol exchange drying was decreased by 18% and 22%, and 0 and 17%, respectively, while the permeability of sapwood and heartwood was 0.439 and 0.060 darcy respectively, which was increased by 85% and 49% respectively. The permeability difference of soaking sapwood and heartwood versus their controls was very significant at the 0.1% level by t-test.     

Bordered pits in xylem of vesselless angiosperms and their possible misinterpretation as perforation plates

Vesselless wood represents a rare phenomenon within the angiosperms, characterizing Amborellaceae, Trochodendraceae and Winteraceae. Anatomical observations of bordered pits and their pit membranes based on light, scanning and transmission electron microscopy (SEM and TEM) are required to understand functional questions surrounding vesselless angiosperms and the potential occurrence of cryptic vessels. Interconduit pit membranes in 11 vesselless species showed a similar ultrastructure as mesophytic vessel‐bearing angiosperms, with a mean thickness of 245 nm (± 53, SD; n = six species). Shrunken, damaged and aspirated pit membranes, which were 52% thinner than pit membranes in fresh samples (n = four species), occurred in all dried‐and‐rehydrated samples, and in fresh latewood of Tetracentron sinense and Trochodendron aralioides. SEM demonstrated that shrunken pit membranes showed artificially enlarged, > 100 nm wide pores. Moreover, perfusion experiments with stem segments of Drimys winteri showed that 20 and 50 nm colloidal gold particles only passed through 2 cm long dried‐and‐rehydrated segments, but not through similar sized fresh ones. These results indicate that pit membrane shrinkage is irreversible and associated with a considerable increase in pore size. Moreover, our findings suggest that pit membrane damage, which may occur in planta, could explain earlier records of vessels in vesselless angiosperms.     

窖泥群落结构及功能微生物研究进展

窖泥是浓香型白酒的特征发酵载体,包含多种功能微生物,这些功能微生物对浓香型白酒的风格特征和品质有着重要的影响。本文对不同窖龄窖泥、不同浓香型白酒产地的窖泥及不同质量窖泥的窖泥微生物研究进展进行总结分析,并在此基础上对窖泥主体微生物的功能进行阐述。以期为窖泥微生物的研究提供思路,为浓香型白酒的质量和香味成分研究提供思考,促进窖泥微生物的研究,加深对浓香型白酒窖泥的认知。     

Neuronal Substrates for Infrared Contrast Enhancement and Motion Detection in Rattlesnakes

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AN EXPANDED SURVEY OF THE ULTRASTRUCTURE OF RED ALGAL PIT PLUGS1

The fine structure of pit plugs in 90 species of red algae was examined, bringing the total number of species in the continuing survey to 153. The organization of plug caps was confirmed to be a stable, predictable trait within thalli, between generations in heteromorphic life histories, and within the presently recognized orders, with one exception—the Acrochaetiales. Two forms of the outer cap were found in this group, a thin plate, as in the Nemaliales and Palmariales, and a dome, as in Batrachospermales and Corallinales. Variation of pit plug structure indicates that the Acrochaetiales are a heterogeneous assemblage and that pit plugs will be useful in reappraising their systematics. The systematic affinities of several species of uncertain affinities are clarified. Schmitziella endophloea Bornet et Batters is excluded from both orders, Corallinales and Acrochaetiales, with which it previously was allied. Although other ordinal attributions are not precluded by pit plug structure alone, pit plug structure is consistent with placement of Apophlaea sinclairii Harvey and Hildenbrandia rivularis (Liebman) J. Agardh in the Hildenbrandiales, Plagiospora gracilis Kuckuck, Schmitziella endophloea, and Wurdemannia miniata (Duby) J. Feldmann et Hamel in the Gigartinales, and Pseudorhododiscus nipponicus Masuda in the Palmariales.     

ABSENCE OF CAP MEMBRANES AS A CHARACTERISTIC OF PIT PLUGS OF SOME RED ALGAL ORDERS1

The current general model of the organization of a fully developed rhodophycean pit plug includes a cap membrane associated with each end of the plug. Continuity of the plasmalemma and cap membrane results in the plug core being extracellular. However, routine ultrastructural methods have not convincingly demonstrated cap membranes in the Bangiales or the Corallinales. In this study, a variety of fixation regimes that enhance membrane contrast were used in an attempt to detect cap membranes in representatives of these two orders. Although cap membranes were readily and clearly demonstrable by these methods in a representative of an order previously known to have cap membranes, they could not be detected in members of the Bangiales or Corallinales. Should the absence of cap membranes prove to be an invariant feature of these two orders, presence or absence of cap membranes will constitute a new character for phylogenetic analysis. It is proposed that the ancestral character state of red algal pit plugs was a homogeneous plug without caps and without cap membranes.     

ABSENCE OF CAP MEMBRANES AS A CHARACTERISTIC OF PIT PLUGS OF SOME RED ALGAL ORDERS1

The current general model of the organization of a fully developed rhodophycean pit plug includes a cap membrane associated with each end of the plug. Continuity of the plasmalemma and cap membrane results in the plug core being extracellular. However, routine ultrastructural methods have not convincingly demonstrated cap membranes in the Bangiales or the Corallinales. In this study, a variety of fixation regimes that enhance membrane contrast were used in an attempt to detect cap membranes in representatives of these two orders. Although cap membranes were readily and clearly demonstrable by these methods in a representative of an order previously known to have cap membranes, they could not be detected in members of the Bangiales or Corallinales. Should the absence of cap membranes prove to be an invariant feature of these two orders, presence or absence of cap membranes will constitute a new character for phylogenetic analysis. It is proposed that the ancestral character state of red algal pit plugs was a homogeneous plug without caps and without cap membranes.     

Foraging in the ant-lionMyrmeleon mobilis hagen 1888 (neuroptera: Myrmeleontidae): Behavioral flexibility of a sit-and-wait predator

The relative effects of foraging benefits (food intake) and costs (disturbance = pit destruction) on growth rate and foraging behavior of larvae of the ant-lionMyrmeleon mobilis were investigated. In a laboratory experiment second-instar larvae were subjected to combinations of three rates of feeding and three rates of disturbance. Pit relocations were generally rare but occurred more often in starved larvae. Disturbance rate had no significant effect on pit relocation rate. Feeding rate was a major determinant of the energy allocated in pit construction and maintenance (positive relationship). In a second experiment third-instar larvae encountered changing rates of disturbance. Pit size was reduced as a response to increased rates of disturbance. Disturbance had no detectable effect on growth. In general,M. mobilis larvae were cost-conservative, foragers.     

中国裸子植物木材具缘纹孔构造类型的研究

根据100种中国裸子植物木材(隶属4纲、8目、11科,42属)具缘纹孔构造的研究,提出8种不同具缘纹孔类型:1.苏铁型;2.南洋杉 A 型;3.南洋杉 B 型;4.落羽杉 A 型;5.落羽杉 B 型;6.松木 A 型;7.松木 B 型;8.买麻藤型。A 型是指纹孔室内瘤状层缺乏或罕见,B型则具明显的瘤状层。并对具缘纹孔在系统发育中的变化进行了讨论。