传染性法氏囊病病毒中国强毒株A节段cDNA基因的克隆和序列分析

以来自哈尔滨传染性法氏囊病病毒（ＩＢＤＶ） 强毒株（Ｈａｒｂｉｎ 毒株,Ｈ） 的基因组ＲＮＡ为模板,用反转录聚合酶链反应（ＲＴ－ ＰＣＲ） 的方法得到了其Ａ 节段的全长ｃＤＮＡ 片段,分５＇端（１ ６５９ｂｐ） 和３＇端（１ ４４４ｂｐ） 上下两段分别克隆到ｐＧＥＭＢ○Ｒ － Ｔ 载体上,测定了其核苷酸顺序,在长为３ １０１ ｂｐ 中含有两个阅读框ＯＲＦＡ１ 和ＯＲＦＡ２ ,分别编码１ ０１２ 个氨基酸的前体蛋白（ＶＰ２ － ４ －３） 和１４５ 个氨基酸的ＶＰ５,ＯＲＦＡ１ 和ＯＲＦＡ２ 有部分的重叠。将核苷酸序列及推测出的氨基酸序列与已报道的ＩＢＤＶ 血清Ⅰ型和Ⅱ型毒株的相应序列进行了比较,结果表明：Ｈ 毒株与其它血清Ⅰ型毒株之间,在核苷酸水平上存在２５ｂｐ － ２６７ｂｐ 的差异;在氨基酸水平上存在１７ ～４０ 个氨基酸的差异。在ＶＰ２ － ４ － ３ 内比较显示,Ｈ 毒株与Ｐ２ 、Ｃｕ－ １ 之间氨基酸的差异最小为１ ．７％ ,Ｈ 毒株与ＵＫ６６１ 之间氨基酸的差异最大为３ ．９ ％ 。变异主要发生在ＶＰ２ 的可变区（２０６ － ３５０ 位氨基酸） ,在Ｈ 毒株所特有的１２ 个氨基酸当中,该区就占５ 个,代表１ ．７６ ％ 的变异。ＶＰ４、ＶＰ３ 和ＶＰ５区各有     

UV—B及红光对大棚番茄品质的影响

冬季蓝色无谪膜塑料大棚内有效光合辐射（ＰＡＲ）和紫外Ｂ（ＵＶ－Ｂ）都比棚外低,给大棚番茄补充照射ＵＶ－Ｂ和红光。结果表明,红光可提高番茄果实糖、酸含量。高剂量ＵＶ－Ｂ（０．９５ｋｊ．ｍ＾－１．ｄ＾－１,０．７１ｋｊ．ｍ＾－２．ｄ＾－１）降低番茄红素Ｃ（Ｖｃ）的含量,低剂量ＵＶ０－Ｂ（０．５４ｋｊ．ｍ＾－１．ｄ＾－１,０．６５ｋｊ．ｍ＾－２．ｄ＾－１）可提高番茄红素和Ｖｃ含量。低剂量ｋｊ．ｍ＾－２．     

增强UV-B辐射对小麦叶中CAT、POX和SOD活性的影响

研究了０（ＣＫ）,８．８２ｋＪ／ｍ＾２（Ｔ１）及１２．６ｋＪ／ｍ＾２（Ｔ２）三种剂量的紫外线Ｂ（ＵＶ－Ｂ,２８０～３２０ｎｍ）辐射对温室种植的小麦膜伤害的机理,试验结果表明,在增强ＵＶ－Ｂ辐射下,与对照相比,膜脂过氧化物产－丙二醛（ＭＤＡ）含量明显升高,同时膜脂脂肪酸组成配比改变,不饱和度指数（ＩＵＦＡ）有所下降,并具剂量效应,过氧化氢酶（ＣＡＴ）,过氧化物酶（ＰＯＸ）活性显著升高,而超氧歧化酶（     

UV—B辐射对小麦叶片H2O2代谢的影响

研究了温室种植的小麦在０（ＣＫ）、８．８２ｋＪ／ｍ＾２（Ｔ１）和１２．６ｋＪ／ｍ＾２（Ｔ２）三种剂量的紫外线Ｂ（ＵＶ－Ｂ）辐射下Ｈ２Ｏ２含量的变化及其机理。ＵＶ－Ｂ辐射下Ｈ２Ｏ２、还原型抗坏血酸（ＡｓＡ）和还原型谷胱甘肽（ＧＳＨ）含量增加,抗坏血酸过氧化物酶（ＡＰｘ）和谷胱甘肽不原酶（ＧＲ）活性升高,脂肪酸不饱和度指数（ＩＵＦＡ）降低。ＳＤＳ－ＰＡＧＥ谱图没有质上的差异,但凝胶着色深浅有变化。分析     

增强UV-B辐射对小麦叶片内源ABA和游离脯氨酸的影响

研究温室种植的小麦在０（ＣＫ）、８．８２ＫＪ／ｍ＾２（Ｔ１）和１２．６ＫＪ／ｍ＾２（Ｔ２）３种剂量的ＵＶ－Ｂ辐射下其内源ＡＢＡ和游离脯氨酸含量的变化。ＵＶ－Ｂ辐射导致叶绿体膜脂脂肪酸配比改变和ＩＵＦＡ降低,叶片ＭＤＡ含量升高及ＡＢＡ和游离脯脯氨酸积累。分析表明,ＵＶ－Ｂ辐射对膜系统的损坏也许是内源ＡＢＡ和游离脯氨酸含量增加的原因之一,而后者也是植物抵抗ＵＶ－Ｂ胁迫所做出的适应性反应。     

抗黄矮病小麦新品系YW443的分子细胞遗传学鉴定

以小麦－中间偃麦草二体附加系Ｌ１衍生抗病系ＰＰ９－１为抗源,与小麦推广品种陕７８５９．丰抗８号杂交并自交,在Ｆ６代中选到农艺性状优良的高抗黄矮病小麦新品系ＹＷ４４３。对ＹＷ４４３及其亲本进行抗病性鉴定。结果表明：ＹＷ４４３高抗大麦黄矮病毒ＧＰＶ、ＧＡＶ株系。利用基因组原位杂交,ＲＦＬＰ分析和ＲＡＰＤ分析,研究诉遗传构成及其抗病基因染色体归属。结果表明：ＹＷ４４３（２ｎ＝４３）的遗传构成了４０条（２     

重离子束对酵母细胞的失活与突变

双倍体酵母细胞Ｄ７经单核能为１１．４ＭｅＶ／ｕ的Ａｎ和Ｕ离子辐照后,测定了细胞随剂量的存活率和突变率。获得细胞对Ａｕ和Ｕ离子的失活截面分别为２．５４μｍ２和１．９２μｍ２。在存活率为３７％的条件下,Ａｕ、Ｕ离子的ＲＢＥ分别为０．２８和０．１９。在突变实验中,研究了ＤＮＡ断链后的重组与倒位,它们对Ａｕ和Ｕ离子的截面为：８．３×１０－２μｍ２［σｍ－ｒｅｃ（Ａｕ）］,９．５×１０－５μｍ２［σｍ－ｒｅｃ（Ｕ）］和６．１×１０－４μｍ２［σｍ－ｒｅｖ（Ａｕ）］和３．８×１０－５μｍ２［σｍ－ｒｅｖ（Ｕ）］．最后,对所获结果进行了讨论。     

紫外光B辐射对菠菜叶片脂质过氧化作用的影响

菠菜（ＳｐｉｎａｃｉａｏｌｅｒａｃｅａＭｉｌ．）品种“华菠一号”生长在室内条件下,以０．０和１３．０ｋＪ·ｍ－２·ｄ－１的ＵＶＢ进行照射处理,研究了ＵＶＢ对菠菜叶片内类黄酮和脂质过氧化作用的影响。结果表明：ＵＶＢ辐射降低了菠菜的单株叶鲜重,诱导了体内吸收ＵＶＢ的类黄酮化合物的大量积累,并使可溶性蛋白含量与叶绿素含量下降。ＵＶＢ辐射能使菠菜叶片内Ｏ－·２及丙二醛（ＭＤＡ）含量大幅度上升,而使抗坏血酸（ＡｓＡ）含量下降。ＵＶＢ辐射能使菠菜叶片内过氧化物酶（ＰＯＸ）、ＳＯＤ的活性大幅度上升,而过氧化氢酶（ＣＡＴ）活性仅略有增加。初步推测：ＵＶＢ辐射首先诱导菠菜叶片内Ｏ－·２的积累,并导致膜脂质过氧化作用,从而抑制菠菜生长。Ｏ－·２的积累能诱导抗氧化酶活性的上升,但抗氧化酶活性的上升和吸收ＵＶ的类黄酮化合物的积累并不能扭转ＵＶＢ对菠菜的伤害。     

糖皮质激素及其他甾体激素对大鼠下丘脑薄片释放精氨酸加压素的影响

本工作采用离体孵育技术,观察大鼠下丘脑薄片（含有室旁核和视上核）释放精氨酸加压素（ＡＶＰ）和糖皮质激素（ＧＣ）及其他甾体激素对ＡＶＰ释放的快速影响。结果如下：（１）大鼠下丘脑薄片经过９０ｍｉｎ的恢复之后,在长达６ｈ的孵育过程中能够相当稳定地释放ＡＶＰ,释放量为９．０６±１．２３ｐｇ／ｍｉｎ;（２）皮质酮（Ｂ）在２０ｍｉｎ内可明显地抑制ＡＶＰ的释放,在１０－７—１０－４ｍｏｌ／Ｌ范围内呈剂量－效应关系;（３）在同一剂量（１０－６ｍｏｌ／Ｌ）,皮质醇、１７β－雌二醇和睾丸酮也可快速地抑制ＡＶＰ的释放,而相同剂量的地塞米松、醛固酮、孕酮、ＲＵ４８６和胆固醇却无此效应;（４）ＲＵ４８６（１０－７—１０－３ｍｏｌ／Ｌ）对ＡＶＰ的释放没有影响,但却能（１０－５—１０－３ｍｏｌ／Ｌ）部分地阻断Ｂ的快速抑制效应。这些结果表明,ＧＣ对大鼠下丘脑ＡＶＰ的释放具有不通过传统的基因组机制的快速抑制效应,此种抑制效应可能与ＧＣ的负反馈调节作用有关。     

延髓头端腹外侧区血管升压素能机制在应激性高血粘度中的作用

观察延髓头端腹外侧区（ｒＶＬＭ）微量注射血管升压素（ＡＶＰ）能否影响正常大鼠的血压和血粘度,并分析ｒＶＬＭ内ＡＶＰ能机制在清醒大鼠经悬吊加束缚引起应激性升压反应和高血粘度中的影响。结果如下：⑴正常大鼠双侧ｒＶＬＭ微量注射ＡＶＰ（每侧０．５μｇ／０．５μｌ）,可引起血压和血粘度升高;此作用可被事先在同一位置微量注射ＡＶＰ－Ｖ１受体拮抗剂ｄ（ＣＨ２）５「Ｔｙｒ（Ｍｅ）＾２」ＡＶＰ（每侧０．１μｇ／０．     

商洛低山丘陵区农林复合生态系统光能竞争与生产力

农林复合系统是改善商洛低山丘陵区脆弱生态环境、促进该区域经济发展的重要举措。以该区具有代表性的核桃(Juglans regia L.)、大豆(秦豆8号)和丹参(Radin salviae Miltiorrhizae)农林复合模式为对象,研究不同农林复合系统对光能分布、农作物生长、生产的影响。研究结果表明,不同复合模式下,大豆、丹参的光合有效辐射、光合速率、生物量及产量均有不同程度的下降,且距树行愈近,影响愈大。叶片水势与大豆、丹参的光合速率、生物量以及产量不相关或负相关,而15—30 cm土壤含水量与大豆的生物量和产量以及丹参的生物量正相关,大豆、丹参的生产量与其光合有效辐射呈显著正相关性,这说明农林复合系统中光能竞争是导致间作大豆、丹参产量下降的主要原因。     

光能竞争对农林复合生态系统生产力的影响

农林复合生态系统是改善渭北黄土区脆弱生态环境、促进该区域经济发展的重要举措.以该区具有代表性的核桃(Juglans regia L.)、李子(Prunus salicina),绿豆(秦豆6号)、辣椒(陕椒981)农林复合模式为对象, 研究不同农林复合系统对光能分布、农作物生长、生产的影响.研究结果表明,不同复合模式下,玉米、辣椒的光合有效辐射、光合速率、生物量及产量均有不同程度的下降,且距树行愈近,影响愈大.叶片水势与玉米、辣椒的光合速率、地上部分生物量以及产量不相关或负相关.而10～20cm土壤含水量与绿豆的生物量和产量以及辣椒的地上部分生物量正相关.但绿豆、辣椒的生产量与其光合有效辐射呈显著正相关性,这说明,农林复合系统中光能竞争是导致间作绿豆、辣椒产量下降的主要原因.     

Analysis of theFusarium toxins Deoxynivalenol and Zearalenone in Austrian feeds of the crop years 2002 and 2003

164 feed samples were collected in Lower Austria, Upper Austria, Styria and Carynthia in the crop years 2002 and 2003 and were analysed by means of the RIDASCREEN^® ELISA-assay for theFusarium toxins Deoxynivalenol (DON) and Zearalenone (ZON). The collected samples consisted of swine feeds, cereals and silages. DON concentrations were found up to the range of mg/kg (ppm), in contrast ZON results remained significantly lower.     

Action of ultraviolet radiation (UV-B) upon cuticular waxes in some crop plants

The surface structure and composition of surface lipids were examined in leaves of barley, bean, and cucumber seedlings grown in a growth chamber under white light and low levels of ultraviolet (UV-B; 280–320 nm) radiation. The cuticular wax of cucumber cotyledons and bean leaves appeared as a thin homogeneous layer, whereas on barley leaves crystal-like structures could be observed under these irradiation conditions. Principally, the amount of cuticular wax found in barley leaves was five times greater than in bean or cucumber leaves. The prediominant wax components were primary alcohols in barley, primary alcohols and monoesters in bean, and alkanes in cucumber cotyledons. Irradiation with enhanced UV-B levels caused an increase of total wax by about 25% in all plant species investigated. Aldehydes, detected as a minor constituent of cucumber and barley wax, increased twofold. Distribution patterns of the homologs within some wax classes were different at low and enhanced UV-B levels. In general, the distribution of the homologs was shifted to shorter acyl chain lengths in wax of leaves exposed to enhanced UV-B levels. This was most apparent in cucumber wax, less in bean or barley wax. The UV-B-caused effects upon cucumber wax were mainly due to a response by the adaxial surface of the leaf.Abbreviation UV-B Ultraviolet radiation (280–320 nm)     

Joint effects of acetochlor and urea on germinating characteristics of crop seeds

Neuraminidase (NA) is one of the most important targets to screen the drugs of anti-influenza virus A and B. After virtual screening approaches were applied to a compound database which possesses more than 10000 compound structures, 160 compounds were selected for bioactivity assay, then a High Throughput Screening (HTS) model established for influenza virus NA inhibitors was applied to detect these compounds. Finally, three compounds among them displayed higher inhibitory activities, the range of their IC5o was from 0.1 μmol/L to 3 μmol/L. Their structural scaffolds are novel and different from those of NA inhibitors approved for influenza treatment, and will be useful for the design and research of new NA inhibitors. The result indicated that the combination of virtual screening with HTS was very significant to drug screening and drug discovery.     

粤西及相邻地区太阳总辐射、光合有效辐射能量和光量子通量时空分布

应用普适全国的计算太阳辐射、光合有效辐射和光量子通量模型,系统地研究了粤西的高要、封开和临近地区梧州的太阳辐射、光合有效辐射和光量子通量的年总量、月总量以及相应的年平均日总量和日平均日总量。结果表明,太阳辐射、光合有效辐射和光量子通量的年变化有相似的规律;而地区变化有以下特点：梧州和封开明显类似,而高要与上两地差异稍大。     

大气气溶胶增加对作物的影响研究进展

大气气溶胶是指悬浮在大气中的固态和液态颗粒物总称。近年来空气污染带来了一些区域大气气溶胶浓度上升明显,一定程度上对作物生长环境带来影响。国内外关于大气气溶胶增加可能对作物产生的影响表现在:(1)大气气溶胶增加会导致直接辐射减少,而散射辐射可能会有一定程度增加;散射辐射增加有利于一些作物整个冠层光合能力的提高。(2)大气气溶胶带来辐射的改变也会影响近地面小气候环境,尤其是大气昼夜温度变化,从而影响作物干物质积累;而辐射与温度的改变同时也会影响农田蒸散和最终水分利用效率。(3)大气气溶胶形成的干沉降会停留在叶片表面,减少光合有效辐射到达叶片的量,同时对作物叶片结构和功能产生直接影响。在总结国内外研究进展基础上,提出未来关于大气气溶胶增加对作物影响需要进一步明确大气气溶胶带来的作物生长环境改变对作物碳同化、积累和消耗的影响以及直接和散射辐射比例改变如何影响作物光合和蒸腾的相互关系,通过全面系统的研究大气气溶胶对作物产量形成的影响机制,提出有针对性的田间应对技术。     

China's crop productivity and soil carbon storage as influenced by multifactor global change

Much concern has been raised about how multifactor global change has affected food security and carbon sequestration capacity in China. By using a process‐based ecosystem model, the Dynamic Land Ecosystem Model (DLEM), in conjunction with the newly developed driving information on multiple environmental factors (climate, atmospheric CO₂, tropospheric ozone, nitrogen deposition, and land cover/land use change), we quantified spatial and temporal patterns of net primary production (NPP) and soil organic carbon storage (SOC) across China's croplands during 1980–2005 and investigated the underlying mechanisms. Simulated results showed that both crop NPP and SOC increased from 1980 to 2005, and the highest annual NPP occurred in the Southeast (SE) region (0.32 Pg C yr^?1, 35.4% of the total NPP) whereas the largest annual SOC (2.29 Pg C yr^?1, 35.4% of the total SOC) was found in the Northeast (NE) region. Land management practices, particularly nitrogen fertilizer application, appear to be the most important factor in stimulating increase in NPP and SOC. However, tropospheric ozone pollution and climate change led to NPP reduction and SOC loss. Our results suggest that China's crop productivity and soil carbon storage could be enhanced through minimizing tropospheric ozone pollution and improving nitrogen fertilizer use efficiency.     

应用差异蛋白质组学方法分析作物化感作用的分子机理

试验旨在分析运用分子标记技术(QTL)和差异蛋白组学技术研究作物化感作用分子机理的差异性。首先运用差异蛋白组学技术探讨在生物胁迫(稗草)下水稻化感作用潜力变化的内在分子机理。分别用稗草和水稻的根系分泌物培养切自一株5叶龄化感水稻P I312777植株并经恢复的2个分蘖。7d后,提取处理和对照相同叶位叶片的全蛋白质并进行双向电泳,每张电泳胶片上获得800多个电泳胶点,其中差异表达的蛋白质点有4个。采用M ALD I-TOF-M S对各差异蛋白质点进行肽质量指纹图谱分析,经过SW ISS-PROT数据库查询,结果表明化感水稻P I312777在稗草胁迫下的特异蛋白分别与苯丙氨酸氨解酶(PAL)、硫还原型蛋白(T rx-m)、3-羟基-3-甲基戊二酰辅酶A还原酶(HM GR)和过氧化物酶(POD)相匹配。根据编码以上4个差异蛋白质的DNA序列,发现编码以上4个差异蛋白的基因分别位于水稻染色体4、7、8和12上的特定克隆位点,这就是与化感作用相关基因。前人也运用QTL方法开展作物化感作用的分子机理研究,但由于所采用的供体材料、受体植物及对表型性状的评价方法等的不同,定位结果存在较大的差异。综合比较两种方法后认为,运用差异蛋白组学技术分析水稻化感作用的分子机理,比QTL技术更加直接和深入。因为比较胁迫处理和对照植物组织的2-DE图谱将能鉴定出由表达候选基因编码的胁迫蛋白质,氨基酸残基序列的测定将揭示那些功能与胁迫性状密切相关的蛋白质,这种编码的基因就是兼具功能与表达的候选基因。     

Dosimetric and Monte Carlo verification of jaws-only IMRT plans calculated by the Collapsed Cone Convolution algorithm for head and neck cancers

AimThe aim of this study is to verify the Prowess Panther jaws-only intensity modulated radiation therapy (JO-IMRT) treatment planning (TP) by comparing the TP dose distributions for head-and-neck (H&N) cancer with the ones simulated by Monte Carlo (MC).BackgroundTo date, dose distributions planned using JO-IMRT for H&N patients were found superior to the corresponding three-dimensional conformal radiotherapy (3D-CRT) plans. Dosimetry of the JO-IMRT plans were also experimentally verified using an ionization chamber, MapCHECK 2, and Octavius 4D and good agreements were shown.Materials and methodsDose distributions of 15 JO-IMRT plans of nasopharyngeal patients were recalculated using the EGSnrc Monte Carlo code. The clinical photon beams were simulated using the BEAMnrc. The absorbed dose to patients treated by fixed-field IMRT was computed using the DOSXYZnrc. The simulated dose distributions were then compared with the ones calculated by the Collapsed Cone Convolution (CCC) algorithm on the TPS, using the relative dose error comparison and the gamma index using global methods implemented in PTW-VeriSoft with 3%/3 mm, 2%/2 mm, 1%/1 mm criteria.ResultsThere is a good agreement between the MC and TPS dose. The average gamma passing rates were 93.3 ± 3.1%, 92.8 ± 3.2%, 92.4 ± 3.4% based on the 3%/3 mm, 2%/2 mm, 1%/1 mm criteria, respectively.ConclusionsAccording to the results, it is concluded that the CCC algorithm was adequate for most of the IMRT H&N cases where the target was not immediately adjacent to the critical structures.