水稻外源DNA导入系的创建及主要性状分析

通过花粉管通道法将稗草总体DNA和玉米总体DNA导入水稻受体R122中,获得的D1代变异频率分别高达1．487％和3．81％。对稳定的3个玉米DNA导入系和4个稗草DNA导入系研究表明,与受体R122相比,导入系在株型、株高、生育期、分蘖力、着粒密度、粒形、稃尖颜色、稻瘟病抗性、稻米品质、恢复力和耐储藏性等生物学性状方面发生了广泛的变异。同时讨论了外源DNA导入水稻的变异频率和在水稻育种中的应用前景。     

草坪草遗传转化进展与研究热点

随着我国草坪业的快速发展,草坪草遗传育种工作越来越受到人们的关注,生物技术在草坪草品种改良中具有很大的应用潜力。着重从转基因草坪草的类型与目标基因、外植体的选用、转化方法、表达载体的构建、转化体的筛选等方面综述了草坪草转基因研究的现状及其进展,同时对草坪草分子标记和体细胞无性系变异等方面的研究进展作了简要的概述,提出了抗逆、抗病虫与环保型、纯天然彩色草坪草等研究热点。核技术在改良草坪草的观赏性状、抗逆性、抗病性等方面将发挥重要作用。     

乌珠穆沁草原饲养黑安格斯牛肌肉氨基酸组成及营养价值分析

试验旨在分析乌珠穆沁草原饲养的黑安格斯牛肌肉氨基酸组成及其营养价值,为该品种的饲养、杂交繁育及肉品质评价提供基础数据。采集7头体重为500 kg±38 kg黑安格斯肉牛的里脊、臀肉、肩肉、眼肉、上脑、胸肉和米龙等部位肉样,测定其氨基酸含量与组成,并用FAO/WHO氨基酸模式进行营养价值分析。结果显示样品中水分平均含量68.73%,低于国家标准;粗脂肪平均含量为30.56%。并检测出17种氨基酸,鲜味、甜味和苦味氨基酸含量丰富,其与总氨基酸(TAA)含量的比值分别为25.8%、32.7%和41.6%。必需氨基酸(EAA)含量、EAA/TAA、EAA/NEAA及EAA评分均超过FAO/WHO氨基酸模式。在所有测定样品中,眼肉、里脊和上脑氨基酸含量较高,氨基酸组成丰富。综上所述,乌珠穆沁草原饲养的黑安格斯牛肉氨基酸组成丰富,含量较高,能够满足人体营养需要,属于优质蛋白质。     

山东省耕地后备资源宜耕性评价

从生态环境、立地条件、区位指标等3个方面选取了9个评价指标,采用极限条件法对山东省耕地后备资源宜耕性进行评价,并分析不同类型耕地后备资源的空间分布特征。结果表明:山东省耕地后备资源面积为2 100.09km~2,仅占山东省土地总面积的1.33%,其他以草地为主。空间分布呈现出不均衡性,东营市和德州市耕地后备资源数量较多,面积分别为266.59和210.91km~2;青岛市、聊城市、淄博市和威海市耕地后备资源较少,占山东省耕地后备资源面积的比例均3%。不同类型耕地后备资源空间分布差异明显。可开垦其他草地和可开垦内陆滩涂空间分布差异相对较小;可开垦盐碱地和可开垦裸地空间分布集聚特征明显;其他可开垦耕地后备资源数量较少,但空间分布差异较大;可复垦采矿用地的空间分布整体上呈现出"西多东少,南多北少"的空间格局。集中连片耕地后备资源面积为576.67km~2,占耕地后备资源总面积的27.46%。相对稀缺、零散破碎化程度较高、空间分布差异显著是山东省耕地后备资源的主要特征。耕地保护不应只注重占补耕地的数量和质量,还应通过适度规模经营等提高对现有耕地的利用效率,因地制宜加强对各类型耕地后备资源的合理保护和高效利用。     

含钼铜精矿氧化焙烧-浸出分离钼研究

四川攀西地区的含钼铜精矿中,由于钼、铜矿物组成复杂,共生关系紧密,提出了氧化焙烧-浸出工艺进一步分离钼。将试样置入焙烧炉中进行氧化焙烧,使硫化物转化为CuO、MoO₃、Fe₂O₃等氧化物后;添加NaOH、H₂O与MoO₃反应生成可溶性Na₂MoO₄,浸出渣作为铜精矿产品。研究结果表明：铜、钼等以氧化物形式赋存于焙烧矿中,氧化焙烧矿中的硫含量较低为0.53%,硫以SO₂气相形式挥发;在焙烧温度650℃、焙烧时间120 min、氢氧化钠用量为30%、浸出温度60℃、浸出时间120 min、浸出液固比2∶1的综合条件下,钼的浸出率为94.24%,铜精矿（浸出渣）中铜的质量分数为24.27%,钼分离效果明显。     

Identification and Fine Mapping of Heading Date Related Mutant Gene in Rice

A rice heading-date-related mutant was isolated from a 60 Co-γ-ray-induced mutation pool of Zhejing 22,a conventional japonica cultivar in Zhejiang Province,China.The mutant was characterized by a delayed heading date of almost 20 d longer than the wild type plant.Genetic analysis revealed that the mutation was controlled by a single nuclear-encoded recessive gene that was designed as HD(t)(heading date tentatively).To isolate the HD(t) gene,a map-based cloning approach was employed using 479 F 2 mutant individual plants derived from the cross between the hd(t) mutant(japonica) × Zhenshan 97(indica).Finally,the HD(t) gene was mapped to an approximate 53 kb region between the insertion and deletion(InDel) markers of 10-61W and 10-66W on chromosome 10.According to the genome sequence of Nipponbare,the target region contains 11 annotated genes.It is helpful for future cloning of HD(t) gene based on this fine mapping results.     

丹皮酚对LLO诱导大鼠肠黏膜微血管内皮细胞分泌NO、ET-1的影响

为了研究李斯特菌溶血素(LLO)对大鼠肠黏膜微血管内皮细胞(RIMVECs)分泌一氧化氮（NO）、内皮素-1（ET-1）的影响,阐释作为治疗李斯特菌病方剂中单味中药丹皮的有效成分丹皮酚(Pae)调节LLO诱导细胞分泌紊乱的作用机理,试验将培养的RIMVECs分为LLO+Pae组、LLO组、Pae组、空白组,通过MTT比色法测定细胞生长情况;硝酸还原酶法测定细胞上清液细胞因子NO浓度以及酶联免疫法检测ET-1浓度;并用原位杂交方法对结果进行验证;结果显示LLO组与其他各组相比：细胞增殖显著性下降;12小时内,NO、ET-1分泌量高于正常水平,并导致NO／ET-1比值失衡（下降）;而LLO+Pae组NO/ET-1的比值显著上调;由此可见,Pae可以通过改善LLO引起细胞因子NO、ET-1失衡,有效调节细胞微环境,部分解释了中药丹皮治疗李斯特菌病的作用机理。     

重庆四面山暖性针叶林林冠截留及其影响因素

为探讨长江三峡库区次生植被的森林水文作用,对重庆四面山暖性针叶林的林冠截留影响因素及林冠截留效应进行了研究.结果表明:①该地区暖性针叶林林冠截留主要受气象因素和林分郁闭度的影响,各气象因子对林冠截留影响程度顺序依次为降雨量＞降雨强度＞气温＞空气湿度＞风速,其中,降雨量是影响林冠截留的主导因素;林分郁闭度越大,林冠截留量...     

The Toxicology of Native Fucosylated Glycosaminoglycans and the Safety of Their Depolymerized Products as Anticoagulants

Fucosylated glycosaminoglycan (FG) from sea cucumber is a potent anticoagulant by inhibiting intrinsic coagulation tenase (iXase). However, high-molecular-weight FGs can activate platelets and plasma contact system, and induce hypotension in rats, which limits its application. Herein, we found that FG from T. ananas (TaFG) and FG from H. fuscopunctata (HfFG) at 4.0 mg/kg (i.v.) could cause significant cardiovascular and respiratory dysfunction in rats, even lethality, while their depolymerized products had no obvious side effects. After injection, native FG increased rat plasma kallikrein activity and levels of the vasoactive peptide bradykinin (BK), consistent with their contact activation activity, which was assumed to be the cause of hypotension in rats. However, the hemodynamic effects of native FG cannot be prevented by the BK receptor antagonist. Further study showed that native FG induced in vivo procoagulation, thrombocytopenia, and pulmonary embolism. Additionally, its lethal effect could be prevented by anticoagulant combined with antiplatelet drugs. In summary, the acute toxicity of native FG is mainly ascribed to pulmonary microvessel embolism due to platelet aggregation and contact activation-mediated coagulation, while depolymerized FG is a safe anticoagulant candidate by selectively targeting iXase.     

良种体系——现代农业的起跑器

发展现代农业是新农村建设的首要任务。现代农业是先进科技的农业,其发展要靠多种因素推动,但种子是现代农业最重要的科技载体,在现代农业发展中起着基础性和先导性作用。本文结合江苏农业发展实际,阐述了建设良种体系在农业发展中的重要作用,围绕现代农业发展要求,提出了突破良种体系建设的几点思考和建议。