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1.
2021年6月12日,在甘肃省张掖市张掖国家湿地公园东侧入口附近进行鸟类调查时,于毗邻省道S301的浅水沼泽区(100°27′57.81″E,39°59′27.21″N,海拔1405 m)发现2对体色近黑色的鸥科Laridae鸟类,并拍摄到其孵卵的清晰照片(图1).  相似文献   

2.
《广西植物》1992,(4):391-401
Abies 325 faberi 15 forrestii 325 Ias‘ocorPa 327 Pi”dro即327 ‘aehal‘”e”s‘5 327 口eitehi玄327Aeaeia co”f.sa 369 riehi‘281Aeoly夕ha 205 a.‘tral‘5 205 broehy‘tochya 205 gog.epoi.i‘205 hete阳stoehyo 205 hisPiba 205 206 k口rrii 205 Iaeei 205 “ame”515 205 口ilkesia”。205 206 var.明arg亡”ota 206ACantbaCeae 374Aea”thoPo”o二 eoodiaefolfos 266Acer 111 eaPPadoe‘cum subsP.tr“”eat“m 225 Vst.51月iC”明17 eataIP‘folf‘。17 caudat“杭 var.Pratt“17 dat,fdi‘16 e阴eie”se 17 eria…  相似文献   

3.
为考察道路和道路施工对若尔盖高寒泥炭湿地野生动物的影响,我们在穿过若尔盖湿地的2条道路两侧,对距道路不同距离的小型兽类和鸟类分布进行了调查,其中小型兽类调查深度距离公路800m,鸟类调查深度距离公路400m。施工中的国道213线路两侧黑唇鼠兔(Ochotonacurzoniae)洞穴高密度区域离道路更远,在道路两侧400m处达到峰值,极显著高于距离道路10m处的密度;而在正常运营中的省道209线两侧,其洞穴密度在200m处达到最高值,与其他距离的洞穴密度没有显著性差异。无论在国道213线还是省道209线,道路对高原鼢鼠(Myospalaxbaileyi)洞穴分布的影响均未达到显著性水平。在正常运营的省道209线两侧,高原鼢鼠土堆密度最高区域为距离道路100m处;而施工的道路两侧高原鼢鼠土堆密度最高区域则出现在距离道路10m处,第二高峰出现在距离道路400m处。雀形目和隼形目鸟类的分布均呈现距离道路越远密度越高的趋势,但是只有距离道路400m处雀形目鸟类的密度显著高于50m与200m处;距离道路不同距离的样线中隼形目鸟类密度和物种丰富度没有显著性差异。由此可以看出,施工中的道路对黑唇鼠兔的影响区域比正常运营的道路更宽,其公路效应域达到400m,400m的调查深度对鸟类尤其是隼形目鸟类来说可能还略有不足。但是,根据此深度的调查可以确定施工中的国道213线雀形目和隼形目鸟类的公路效应域宽度大于400m。  相似文献   

4.
【目的】筛选亚低温条件下抗线虫和促进植物生长发育的菌株。【方法】采用线虫击倒率测定、室内耐低温测定、拮抗测试和盆栽生物测定相结合的方法进行功能菌株的筛选;采用表型特征、生理生化特征、16S r RNA基因序列测定相结合的多相分类技术对筛选的菌株进行鉴定。【结果】从根结线虫多发的设施黄瓜和番茄病土中分离出细菌和放线菌297株;经对根结线虫击倒率的初步筛选,得到校正击倒率大于70%的活性菌株9株;通过复筛获得1株在亚低温条件下同时具有防线虫、防土传病原菌病、促生特性的生防菌株S205;菌株S205被鉴定为抗生素链霉菌(Streptomyces antibioticus)。【结论】获得一株在亚低温条件下同时具有抗线虫活性和促进植物生长发育的生防菌株S205,该研究对解决亚低温条件下根结线虫的防治具有重要意义。  相似文献   

5.
同源比对黑曲霉XZ-3S木聚糖酶基因xyn ZF-2氨基酸序列,模拟构建木聚糖酶三维结构,确定能够提高酶热稳定性的最佳突变位点。在C-端引入二硫键,突变xyn ZF-2 205位点的色氨酸和52位点的丙氨酸为半胱氨酸,获取突变基因T205C-A52C,表达于大肠杆菌BL21(DE3)。酶学性质比较发现,突变酶Xyn ZFT205C-A52C的最适温度为50℃,比原酶Xyn ZF-2提高了10℃;50℃保温5 min,突变酶相对酶活性为55.36%,原酶相对酶活性为32.62%;原酶与突变酶最适p H均为5.0,但相同p H下突变酶的相对酶活性较原酶高;突变酶的p H稳定区间由原酶的5.0~9.0扩大为3.0~9.0。因此,定点突变T205C和A52C在C-端引入二硫键能提高黑曲霉木聚糖酶Xyn ZF-2热稳定性及p H稳定性。  相似文献   

6.
本研究在柯萨奇病毒B3(coxsackievirus B3,CVB3)基因组P1编码区与P2编码区之间插入一段has-miRNA-205-3p和has-miRNA-205-5p(简称miR-205)的靶序列,得到重组病毒v205T,并比较分析了它在人宫颈癌细胞系HeLa细胞(miR-205低水平表达)和非小细胞肺癌细胞系A549细胞(miR-205高水平表达)中的复制情况。结果表明,插入的miR-205靶序列不影响病毒在HeLa细胞中的复制水平,但抑制了病毒在A549细胞中的复制,病毒滴度为对照的1%以下。为探讨v205T在2株细胞中复制差异的原因,进一步加入miR-205的类似物和抑制物。miR-205类似物可抑制v205T在HeLa细胞中复制和杀伤细胞的水平,而miR-205抑制物可提高v205T在A549细胞中的复制和杀伤细胞的水平。结果表明,v205T的复制确实受miR-205的调控。本研究为开发基于CVB3载体的溶瘤病毒和针对CVB3的减毒活疫苗提供了依据。  相似文献   

7.
目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非梗死区、梗死区、正常对照心肌组织S1P1、S1P2、S1P3的m RNA相对表达。结果:心梗后心室重塑阶段,S1P1 m RNA的表达水平在非梗死区与梗死区的下降程度不一致,1周组非梗死区与正常对照组比较无统计学差异,而在梗死区2组间差异有统计学意义(P0.05),在梗死区降低趋势更为明显。S1P2 m RNA在术后各组的非梗死区与正常对照心肌之间的表达比较,变化无统计学意义,且各时间点之间无差异,而在梗死区其表达变化较为显著(P0.01)。S1P3 m RNA在心梗后1周表达显著增强(P0.01),4周表达出现降低,这种表达抑制在梗死区更为明显(P0.01和P0.05)。结论:心室重塑阶段的S1P1、S1P2、S1P3 m RNA表达在非梗死区与梗死区变化不同步且各有特点,这种差异表达可能在心肌梗死后心室重塑过程中有重要意义。  相似文献   

8.
本研究以羊草(L eym us ch inensis)与灰色赖草(L eym us cinereus)杂种F1代幼穗为外植体诱导愈伤组织,在3.0 m g/L 2,4-D M S培养基上继代1次后,转入不同浓度激素(2,4-D、IAA、KT)配比和不同浓度蔗糖的M S液体培养基进行振荡培养,建立杂种F1代细胞悬浮系和植株再生体系.结果表明,细胞悬浮培养时,M S 1.0 m g/L2,4-D 0.1 m g/L KT 4%蔗糖的液体培养基最佳;悬浮细胞分化时,1.0 m g/L 2,4-D 0.1 m g/L KT 4%蔗糖 M S和1.0 m g/L 2,4-D 4%蔗糖 M S培养的悬浮细胞在1.0 m g/L NAA 0.5 m g/L KT M S分化培养基上的绿苗分化率分别达到83%和80%.细胞悬浮系及再生体系的建立为杂种F1代育性恢复的研究奠定了基础.  相似文献   

9.
魏晓晴  吕广艳  金海威  崔颖  赵莹 《生物磁学》2011,(21):4033-4035
目的:探讨幽门螺杆菌及其热休克蛋白60(H.pylori—HSP60)感染与胃上皮细胞表面DEC205受体的关系。方法:分别用H.pylori、H.pylori-HSP60及E.coliLPS刺激胃上皮细胞KATOIII,利用免疫荧光染色技术观察KATOIII细胞表面DEC205蛋白的表达变化,再利用RT—PCR技术,观察细胞中DEC205mRNA对上述抗原刺激后的变化。结果:H.pylori、H.pylori—HSP60及E.coliLPS的刺激明显引起细胞表面DEC205蛋白的表达以及细胞内DEC205mRNA的产生。结论:H.pylori感染与胃上皮细胞表面的胞吞受体DEC205有着密切的关系。  相似文献   

10.
目的:探讨幽门螺杆菌及其热休克蛋白60(H.pylori-HSP60)感染与胃上皮细胞表面DEC205受体的关系。方法:分别用H.pylori、H.pylori-HSP60及E.coli LPS刺激胃上皮细胞KATOⅢ,利用免疫荧光染色技术观察KATOⅢ细胞表面DEC205蛋白的表达变化,再利用RT-PCR技术,观察细胞中DEC205mRNA对上述抗原刺激后的变化。结果:H.pylori、H.pylori-HSP60及E.coli LPS的刺激明显引起细胞表面DEC205蛋白的表达以及细胞内DEC205 mRNA的产生。结论:H.pylori感染与胃上皮细胞表面的胞吞受体DEC205有着密切的关系。  相似文献   

11.
Hydrobiologia - In 1988–89 a 200 m core was drilled down to granite bedrock in the Pretoria Saltpan as part of a project to ascertain the origin of this unusual feature. The top 90 m of the...  相似文献   

12.
广州街口至良口高速公路对水环境影响的评价分析   总被引:2,自引:0,他引:2  
在对区域水环境现状进行调查分析的基础上,预测了街口至良口高速公路建设工程施工期与运营期对水环境的影响,特别是对流溪河水质的影响程度进行了详细分析。评价和预测结果表明:流溪河水质现状良好,符合相应的水环境功能要求;该工程中两大桥的水下施工分别对下游100和150m范围内水质影响较大,影响属局部短暂性;运营期影响程度较小,通过采取环保措施,对水环境产生的不利影响可以得到减轻或消除。  相似文献   

13.
大型奶牛场粪便厌氧消化工程的研究   总被引:8,自引:0,他引:8  
本文报导了大型牛场粪便厌氧消化工程研究的概况。该工程针对牛粪草多、浮渣多的特点设计了除长草、除浮渣装置。以保证了厌氧消化的稳定运行。工程每天可处理奶牛粪便80余吨、鸡粪及工业发酵废渣20余吨,生产沼气供应2868户职工家庭作燃气使用,平均沼气率为1.2m^3/m^3.d。经后处理的发酵残留物被充分利用,制成肥料、绿色营养土和鱼饵,这样既免除了二次污染,又提高了工程的经济效益。该工程为我国大中型沼气  相似文献   

14.
Species turnover and mobility on a scale of 25 m2 was studied in a montane meadow, which had been transplanted to a location 200 m away from the initial site in the Harz Mountains. The transplantation was performed to preserve this grassland area, which otherwise would have been destroyed by a road construction project. The frequency of 18 endangered species was recorded annually from 1992 to 1996 in 122 quadrats, having a size of 5 × 5 m and being arranged in a coherent block with a total area of 3,000 m2. Many species showed considerable dynamics in settling in the quadrats.  相似文献   

15.
Astropecten marginatus is a sea star widely distributed in Northern and Eastern South America, found on sandy and muddy bottoms, in shallow and deep waters. To describe some of its ecological characteristics, we calculated it spatial-temporal distribution, population parameters (based on size and weight) and diet in the Orinoco Delta ecoregion (Venezuela). The ecoregion was divided in three sections: Golfo de Paria, Boca de Serpiente and Plataforma Deltana. Samples for the rainy and dry seasons came from megabenthos surveys of the "Línea Base Ambiental Plataforma Deltana (LBAPD)" and "Corocoro Fase I (CFI)" projects. The collected sea stars were measured, weighted and dissected by the oral side to extract their stomach and identify the preys consumed. A total of 570 sea stars were collected in LBAPD project and 306 in CFI one. The highest densities were found during the dry season in almost all sections. In LBAPD project the highest density was in "Plataforma Deltana" section (0.007 +/- 0.022 ind/m2 in dry season and 0.014 +/- 0.06 ind/m2 in rainy season) and in the CFI project the densities in "Golfo de Paria" section were 0.705 +/- 0.829 ind/m2 in rainy season and 1.027 +/- 1.107 ind/m2 in dry season. The most frequent size range was 3.1-4.6cm. The highest biomass was found in "Golfo de Paria" section (7.581 +/- 0.018 mg/m2 in dry season and 0.005 +/- 6.542 x 10(-06) mg/m2 in rainy season for 2004-2005 and 3.979 +/- 4.024 mg/m2 in dry season; and 3.117 +/- 3.137 mg/m2 in rainy season for 2006). A linear relationship was found between the sea star size and its weight but no relationship was observed between its size and the depth where it was collected. Mollusks are dominant in the sea star diet (47.4% in abundance). The diet in any of the sections, seasons or between projects or size class was heterogeneous, using multivariate ordinations (MDS) and SIMPER analysis and there was no difference in the prey number or food elements that a sea star can eat. Although A. marginatus has been described as a predator, in this study were also inferred scavenger and detritivorous habits.  相似文献   

16.
玛曲县草地退牧还草工程效果评价   总被引:8,自引:3,他引:5  
王静  郭铌  蔡迪花  邓振镛 《生态学报》2009,29(3):1276-1284
利用残差趋势法对玛曲县草地退牧还草工程(禁牧、休牧)效果进行了评价,即利用2000~2006年250m的MODIS16天合成NDVI产品数据及同期气象资料,建立工程区内退牧前2000~2004年两种时间尺度(年、月),3种空间尺度(县、乡镇、围栏)的NDVI值同气象要素的回归模型,并利用模型预测无该工程影响下的模拟NDVI值,分析退牧前后模拟NDVI值与实际NDVI值的残差及变化趋势,从而判断退牧还草工程对草地恢复状况的影响,及分析不同工程措施对草地恢复的作用.结果表明,退牧还草工程有利于玛曲县草地牧草生长和草地恢复,但草地恢复效果存在时空差异,退牧还草工程有助于牧草整个生育期的生长,尤其是牧草生长初期和末期效果最为显著.禁牧措施较休牧措施对于草地恢复效果更显著.整个工程区内草地总体处于恢复中,但恢复状况各有差异,一些区域草地恢复状况不理想,说明这些区域还存在较为严重的放牧或不合理放牧行为,退牧还草工程执行力度差.就各乡草地恢复状况而言,曼日玛乡草地总体恢复趋势最好,欧拉乡草地总体恢复趋势相对较差.各乡下辖各围栏区草地恢复效果显著,但个别围栏区草地仍处于恶化趋势,其中恢复效果最好的是16# 围栏区,恶化最为严重的是5#围栏区草地.  相似文献   

17.
Conclusion The peripheral membranous and extracellular layers of oocytes at the onset of yolk formation were studied by electron microscopy. It was shown that three cellular layers are present at this time. The outer or surface epithelium contains typical squamous cells. The middle or theca is the connective tissue layer which contains fibroblasts, blood vessels, and collagen fibers. The inner or follicular epithelium proper consists of compactly arrayed follicle cells that have distinct cell boundaries. Two extracellular layers were observed, a coarse granular homogeneous layer and a dense zona radiata. Macrovilli (0.2 in diameter), extensions from the follicle cells, project through the extracellular layers into the peripheral cytoplasm while more numerous microvilli (0.1 in diameter) project up to the dense matrix of the zona radiata. The plasmolemma separating the peripheral cytoplasm from the follicle cells is completely irregular; it forms microvilli. The relations of the enveloping layers as seen with both light and electron microscopes are discussed.This investigation was supported by a Public Health Service research grant (5803-C3) and research career program award (K-3-5356) from the Division of General Medical Sciences.  相似文献   

18.
土壤生物工程在河道坡岸生态修复中应用与效果   总被引:9,自引:3,他引:6  
土壤生物工程是一项采用存活植物构筑边坡结构,稳定河道(流)坡岸和生态修复的工程技术.本文简要讨论了土壤生物工程的原理和活枝扦插、柴笼、灌丛垫以及复合工程等基本种植技术;介绍了我国第一个采用土壤生物工程修复河道坡岸的示范工程,对比了工程实施后河道坡岸10个月来的坡岸土壤剪切力、生境条件和生物多样性变化.研究和示范工程表明,采用土壤生物工程方法可以稳定坡岸、改善坡岸的栖息地质量、修复河道的生态环境.土壤生物工程方法可以在我国各类岸(边)坡的生态修复中广泛运用.  相似文献   

19.
Since December 2001 we have been conducting a project to isolate and determine entire sequences of mouse KIAA cDNA clones which encode polypeptides corresponding to human KIAA proteins. The ultimate goal of this project is the elucidation of the functions of KIAA proteins. A critical step in this project is the generation of antibodies based on the cDNA sequence information. Although antibodies are the most optimal tools for biological analysis, the production and isolation of multiple recombinant proteins for an antigen is a rate-limiting step in antibody production. To address this problem, we established a system utilizing the in vitro recombination-assisted method and shotgun clones that were generated during the sequencing of mouse KIAA cDNAs (DNA Res. 2003, 10, 129-136). The authenticity of the expressed proteins was confirmed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Another critical step for antibody production is the evaluation of the antibodies. Thus, we also made efforts to develop a systematic approach for evaluation of the titer and the specificity of the antibodies. Using these systems, we have produced and evaluated more than 500 antibodies raised against mouse KIAA proteins to date. We are currently generating antibody arrays for analysis of protein expression profiles. We will verify protein-protein interactions using immunoprecipitation and tandem mass spectrometry analysis.  相似文献   

20.
A cytochrome P450 gene, Cyp9m10, is more than 200-fold overexpressed in a pyrethroid resistant strain of Culex quinquefasciatus, JPal-per. The haplotype of this strain contains two copies of Cyp9m10 resulted from recent tandem duplication. In this study, we discovered and isolated a Cyp9m10 haplotype closely related to this duplicated Cyp9m10 haplotype from JHB, a strain used for the recent genome project for this mosquito species. The isolated haplotype (JHB-NIID-B haplotype) shared the same insertion of a transposable element upstream of the coding region with JPal-per strain but not duplicated. The JHB-NIID-B haplotype was considered to have diverged from the JPal-per lineage just before the duplication event. Cyp9m10 was moderately overexpressed in larvae with the JHB-NIID-B haplotype. The overexpressions in JHB-NIID-B and JPal-per haplotypes were developmentally regulated in similar pattern indicating both haplotypes share a common cis-acting mutation responsible for the overexpressions. The isolated moderately overexpressed haplotype conferred resistance, however, its efficacy was relatively small. We hypothesized that the first cis-acting mutation modified the consequence of the subsequent duplication in JPal-per lineage to confer stronger phenotypic effect than that if it occurred before the first cis-acting mutation.  相似文献   

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