土壤风蚀控制研究进展

土壤风蚀是沙漠化过程的重要组成过程和首要环节,是许多国家和地区需要解决的一个主要环境问题.从风蚀的形成机制出发,按性质将控制风蚀的措施分为生物措施、化学措施和机械措施,并简要论述了这些防治风蚀的措施和一些重要结论.根据各地的具体环境和条件,可以单独或配套使用这些措施,以达到控制风蚀的目的;同时,应加强管理,使这些措施发挥其应有的作用,以便进一步改善环境.     

黄龙山林区不同培育措施对油松种群数量动态及物种多样性的影响

根据对黄龙山林区经过抚育、渐伐和封育措施的3类油松林种群开展样地调查,研究了3种培育措施对油松林种群的年龄结构、静态生命表、存活曲线和物种多样性的影响,并运用时间序列模型对不同培育措施的油松林种群数量动态进行了预测.结果表明:3种油松林种群结构特征基本一致,其幼、老龄级个体数较少,中龄级个体数量较大,总体判断黄龙山油松林种群属于稳定状态.在经历3种不同培育措施的油松林群落中,抚育和渐伐措施物种丰富度指数最大;封育措施物种多样性和均匀度指数最大.经过抚育和渐伐措施的油松种群属进展型,而经过封育措施的油松种群属稳定型.说明在黄龙山林区,油松林种群未来应该以封育为主,适当的抚育和渐伐措施为辅,以促进群落持续发育.     

农业非点源污染控制中的最佳管理措施及其发展趋势

农业非点源污染是最主要的一类非点源污染,容易造成水体的富营养化,降低环境的质量,已经成为构成目前水质环境恶化的一大威胁。农业非点源污染具有随机性、广泛性等特点,因此对农业非点源污染的控制相对比较困难。最佳管理措施通过工程措施、耕种措施和管理措施共同作用控制农业非点源污染,可以取得良好的经济效益、社会效益和环境效益。其中工程措施有梯田与山边沟,草沟与植被过滤带、人工湿地、节水灌溉系统等,耕种措施有保护性耕作、等高线种植、合理轮作等,管理措施包括有害生物综合治理、综合肥力管理、农田灌溉制度等。最后,本文还对最佳管理措施的发展趋势作了展望。     

切根和浅耕翻措施对退化草地生长季土壤性质及植物群落的影响

草地退化是我国主要生态问题之一,研究草地不同改良措施的生态效应对于科学有效地恢复草地生态系统具有重要意义。以切根、浅耕翻两种典型改良措施为对象,在内蒙古锡林郭勒盟毛登草原内蒙古大学生态学研究基地研究了两种改良措施对土壤硝化速率、羊草群落植物生物多样性和生物量的影响。结果表明:与对照相比,浅耕翻措施显著降低了土壤硝化速率(P0.05),切根措施对土壤硝化速率有提高效果,且土壤硝化速率呈现出明显的时间动态,土壤硝化速率6月份显著最高、9月份显著最低;浅耕翻措施显著降低了羊草群落植物多样性和生物量(P0.05),而切根处理则显著提高了羊草群落植物多样性(P0.05),切根处理对植物生物量提高有作用但效果不显著。研究结果表明不同草地恢复措施显著影响了土壤性质和植物群落,在短期内,浅耕翻措施不是草地恢复的有效措施,而切根处理有助于提高退化草地生物多样性。     

农业措施在害虫种群无公害控制中的作用

作物抗性品种、布局、耕作制度以及栽培管理等农业措施可以有效地调节害虫的种群数量,合理和综合运用这些措施,可以实现害虫生态调控的目的,从而为农作物的无公害生产提供新的植保技术。本文从农业措施在害虫控制中的直接作用、对天敌昆虫的影响等方面进行了综述,同时对利用农业措施控制害虫的几个问题进行了探讨,以期为合理利用和正确评价农业措施控制害虫提供参考。     

小麦病虫害综合防治技术

通过对小麦病虫害监测及多年资料综合分析,明确了小麦病虫害的科学防控技术措施:提出加强植物检疫、选用多抗优质品种、改进栽培方法等农业措施以及种子消毒、适期化除、开展总体防治等化学防治的综合防控的技术措施.     

急性利培酮中毒救治的临床分析

目的 探讨急性利培酮中毒的发病机制和治疗措施.方法 选择急性利培酮中毒患者18例,应用洗胃、补液、利尿及对症处理等综合治疗.结果 经综合措施治疗,18例患者均痊愈出院.结论 综合救治措施是抢救急性利培酮中毒的有效方法 .     

不同治沙措施对荒漠绿洲过渡带植物群落与土壤因子的影响

沙漠化是河西走廊荒漠绿洲过渡带土地退化的主要原因,科学合理的治沙措施能够有效控制风沙侵害,有助于植被-土壤系统的重建与恢复。多年来,治沙措施的研究主要集中在不同时间梯度下某种给定措施对植物群落及土壤的影响方面,对于同一时间段内不同类型措施产生的生态惠益尚缺乏足够认识。鉴于此,以流动沙地丘间地为对照,选取围栏封育+麦草沙障(Ge+Ws)、麦草沙障+人工梭梭(Ws+H)和尼龙沙障+人工梭梭(Nn+H)3种不同的治沙措施区为研究对象,通过群落学调查与土壤因子测定,研究了不同治沙措施影响下植物群落数量特征和土壤因子的变化规律与相互关系,并对各措施的生态效益进行了评价。结果表明：(1)植被方面,3种治沙措施影响下草本层和灌木层群落数量特征均呈增加趋势,其中Ge+Ws草本层恢复效果较佳,Ws+H和Nn+H灌木层恢复程度更明显;土壤方面,伴随植物群落的恢复,3种治沙措施均能大幅改善土壤全碳、全氮、有机质等主要养分,但同时对土壤水分带来负面效应,Ge+Ws、Ws+H及Nn+H的表层土壤含水量依次减少了37.99%、 31.37%和35.94%。(2)结构方程模型显示,治沙措施通过直接影响灌木和草本群落...     

不同促进愈合措施对荔枝环剥伤口愈合的影响

就荔枝环剥伤口进行不同促进愈合措施处理 ,结果表明 :不同促进愈合措施对伤口愈合有显著作用 ,其中以伤口涂抹黄泥促进愈合的处理 ,愈伤组织发生早 ,生长速度快 ,完全愈合历时短 ;其它促进愈合措施间无显著差异。     

论科学树木养护和园林病虫害防治措施

在我国,园林树木养护一直是一个重要的课题,但是,就目前而言,我国的园林养护还存在着许多的问题,特别是在病虫害方面,必须采取相应的措施,本文对科学树木养护和园林病虫害防治措施做出了简要分析,并提出了一些相应的措施。     

Ethnobotany of Ghalegay, District Swat, Pakistan

Ethnobotanical study of plants revealed that the local community of Ghalegy, District Swat, invariably uses 126 species of 59 families for various purposes. Based on their traditional local uses, fifty-seven species （45.2%） were classifted as medicinal, forty-seven as fire wood （37.3 % ）, forty-five as forage （35.7 % ）, twenty-eight as honey bee species （22.2%）, twenty-seven as vegetable species （21.4%）, 25 as edible fruits （14 wild and llcultivated）, thirteen as timberwood （10.3%）, twelve as ornamental （9.5%）, eleven as furniture wood, ten as shelter and thatch makers （7.9%）, ten as fencing （7.9%）, five as poisonous （4%）, four as religious/superstitious species, three species used in making hand sticks and wooden tools （2.4%）, three as utensil cleaner species （2.4%）, three as evil repellent and one as fish poisoning species. The area is in plant resources and traditional knowledge but it needs ecological management for its sustainability.     

Ethnobotany of Ghalegay,District Swat,Pakistan*

Ethnobotanical study of plants revealed that the local community of Ghalegy, District Swat, invariably uses 126 species of 59 families for various purposes. Based on their traditional local uses, fifty- seven species ( 4512%) were classified as medicinal, forty-seven as fire wood ( 3713%) , forty- five as forage ( 3517%) , twenty- eight as honey bee species ( 2212%) , twenty- seven as vegetable species ( 2114%) , 25 as edible fruits ( 14 wild and 11cultivated) , thirteen as timber wood ( 1013%) , twelve as ornamental ( 91 5%) , eleven as furniture wood, ten as shelter and thatch makers ( 719%) , ten as fencing ( 719%) , five as poisonous ( 4%) , four as religiousPsuperstitious species, three species used in making hand sticks and wooden tools ( 21 4%) , three as utensil cleaner species ( 214%) , three as evil repellent and one as fish poisoning species. The area is in plant resources and traditional knowledge but it needs ecological management for its sustainability.     

农牧结合生态工程的基本理论与实践

农牧结合生态工程是一个复杂的农业生态、经济和技术系统工程,它由植物(种植业)、动物(养殖业)和微生物(连接种养业)3个子系统组成,其关键是建设一个以"四、三、二、一"畜牧业生产模式为主要内容的高效节粮型畜牧生态工程,它要求用尽可能少的自然资源,在尽可能短的周期内,生产尽可能多而优的农(牧)产品,以获取尽可能高的经济效益,达到或维持尽可能最佳的生态平衡.     

Prion protein modifies TGF-beta induced signal transduction

Members of the transforming growth factor-beta (TGF-beta) superfamily regulate a multitude of cellular processes as well as the expression of various proteins such as, e.g., matrix metalloproteinases (MMPs). These endopeptidases selectively degrade components of the extracellular matrix as well as non-matrix substrates like growth factors and cell surface receptors. MMPs are activated during embryonic development, morphogenesis, and tissue resorption/remodeling as well as in pathological conditions such as deranged wound healing and cancer metastasis. In this report we demonstrate that over-expression of cellular prion protein in mouse mammary gland epithelial cells is able to modulate TGF-beta induced signal transduction leading to a synergistic increase of secreted MMP-2 activity. This correlates with elevated substrate detachment of cells grown as an epithelial monolayer as well as interfering with morphogenesis of cells cultured in a three-dimensional collagen type I matrix.     

Comparison between peroxidase-conjugated antigen or antibody and peroxidase-anti-peroxidase complex in a postembedding procedure.

The staining efficiency of peroxidase labeled immunoglobulin conjugate, used either as antigen or as antibody, has been compared with that of peroxidase-anti-peroxidase complex (PAP) on ultrathin sections of araldite embedded material. The conjugate gave positive results in a two layer method as well as in a three layer method when used as antibody. No staining was observed when it was used as antigen. The conjugation seemed to impair the antigenic reactivity of immunoglobulin. The conjugate when used as antibody in the three layer method gave approximately the same staining efficiency as PAP.     

Synthesis of 4-cyanophenyl and 4-nitrophenyl 1,5-dithio-D-ribopyranosides as well as their 2-deoxy and 2,3-dideoxy derivatives possessing antithrombotic activity

1,2,3,4-Tetra-O-acetyl-5-thio-D-ribopyranose as well as its 1-bromide were used as donors in the reaction with 4-cyano- and 4-nitrobenzenethiol, to give the corresponding thioglycosides in different anomeric ratios depending on the reaction conditions. Zemplén deacetylation afforded 4-cyanophenyl as well as 4-nitrophenyl 1,5-dithio-alpha- and beta-D-ribopyranosides, respectively. 1,3,4-Tri-O-acetyl-2-deoxy-5-thio-D-erythro-pentopyranose was synthesized from methyl 2-deoxy-D-erythro-pentofuranoside and was coupled with 4-cyano- and 4-nitrobenzenethiol to give anomeric mixtures from which 4-cyanophenyl as well as 4-nitrophenyl 1,5-dithio-beta-D-erythro-pentopyranosides were isolated after deacetylation. 1,4-Di-O-acetyl-2,3-dideoxy-5-thio-D-glycero-pentopyranose was obtained starting from 1,2,5,6-di-O-isopropylidene-D-mannitol and used as the donor in the glycosylation reaction with 4-cyano- and 4-nitrobenzenethiol. The resulting anomeric mixtures were separated to give, after deacetylation, 4-cyanophenyl as well as 4-nitrophenyl 2,3-dideoxy-1,5-dithio-beta-D-glycero-pentopyranosides. All of these thioglycosides showed significant antithrombotic activity on rats after oral administration.     

Familial true hermaphroditism: paternal and maternal transmission of true hermaphroditism (46,XX) and XX maleness in the absence of Y-chromosomal sequences

We report on 46,XX true hermaphroditism and 46,XX maleness coexisting in the same pedigree, with maternal as well as paternal transmission of the disorder. Molecular genetic analysis showed that both hermaphrodites as well as the 46,XX male were negative for Y-chromosomal sequences. Thus, this pedigree is highly informative and allows the following conclusions: first, the maternal as well as paternal transmission of the disorder allows the possibility of an autosomal dominant as well as an X-chromosomal dominant mode of inheritance; second, testicular determination in the absence of Y-specific sequences in familial 46,XX true hermaphrodites as well as in 46,XX males seems to be due to the varying expression of the same genetic defect; and third, there is incomplete penetrance of the defect.     

Crosstalk between the DNA damage response,histone modifications and neovascularisation

Neovascularisation is critical in several malignant and inflammatory conditions, as well as in the course of eye disorders. During new vessel formation, endothelial cell functions, such as proliferation and sprouting are very important and are regulated by a variety of growth factors. The DNA damage response machinery as well as factors regulating histone modifications, such as histone deacetylases, regulate cell fate as well as gene expression. Recent evidence has pointed to potential interactions among BRCA1, H2AX and SIRT1 in these intracellular pathways and neovascularisation, which will be reviewed here.     

异构化的淀粉水解物用于短梗霉多糖发酵

短梗霉多糖; 发酵; 水解淀粉异构化;     

孕烷X受体的研究进展

核受体是一类高度保守的配体依赖性转录因子家族,在哺乳动物发育、繁殖、免疫应答、心血管功能、组织生长、肿瘤形成、外源物清除及糖类和脂质代谢等生理过程中发挥重要作用。机体对外源物质的清除主要是由孕烷X受体等核受雄介导的。孕烷X受体最早是作为外源物感受器而被研究的,可以被大多数亲脂性药物等外源性化合物及一些内源性化合物如胆汁酸等结构差异很大的配体激活,进而与视黄醇类X受体等形成异源二聚体,结合在ER6、XREM等DNA元件上,调控下游靶基因（包括一相代谢酶、二相结合酶及药物转运体等基因）的表达。此外,孕烷X受体在能量代谢和免疫反应中也有重要作用,参与某些代谢疾病的发生发展,且已在动物模型中被证明是Ⅱ型糖尿病、血脂异常、肥胖症和动脉粥样硬化等代谢疾病治疗的有效靶标。我们主要就其发现、结构、组织分布、作用方式、自身表达的调节等方面的最新研究进行综述。