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排序方式: 共有172条查询结果,搜索用时 17 毫秒
1.
目的建立一种灵敏度高、特异性强、检测速度快的方法检测解脲支原体。方法基于环介导恒温扩增技术(LAMP),根据解脲支原体序列特征设计3对引物进行解脲支原体DNA切口酶核酸恒温扩增,扩增过程在一对引物中标记生物素,随着扩增的进行生物素直接引入扩增片段中,扩增结束后产物在密闭装置中进行免疫试纸条显色反应,根据显色卡的颜色判定结果的阴阳性。结果该技术检测解脲支原体较实时荧光PCR技术灵敏度要高10倍以上,其它病原体检测均阴性该方法特异性与实时荧光PCR技术相当。结论恒温扩增联合试纸条技术检测解脲支原体具有较高的敏感性和特异性,检测速度快,适合各医院开展。  相似文献   
2.
试纸条技术在转基因农作物检测中的应用   总被引:4,自引:0,他引:4  
简述了试纸条技术的基本原理及试纸条技术在转基因农作物检测中的优势与不足 ,并对试纸条技术对转基因农作物检测的应用进行了展望。  相似文献   
3.
Abstract: Identifying and managing Sitka black-tailed deer (Odocoileus hemionus sitkensis) habitat has been an important wildlife issue for many years on the Tongass National Forest of southeastern Alaska, USA. We evaluated habitat selection of Sitka black-tailed deer in the central portion of the region during a winter with snowfall 43% above average using telemetry relocations from 30 individuals that survived the winter. Ivlev indices for habitat selection within home ranges indicated that deer used less than expected, based on availability, north, east, and west aspects, areas >244-m elevation, noncommercial forests, and the low-timber volume stratum while selecting south aspects, areas <153-m elevation, and areas within 305 m of saltwater. Deer used less than expected moderately coarse-canopied forests in the medium- and high-timber volume strata typically found on north slopes while selecting moderately fine-canopied forest in the high-timber volume stratum on south slopes. The lower than expected use of higher volume gap-phase old growth was likely because these were on north aspects where snow accumulated and persisted due to protection from maritime storms. Point relocations suggested less use than expected in clearcuts <41 years of age, while data from 7.2-ha error polygons showed deer were neutral to clearcuts. This suggests that if deer do avoid clearcuts they remain close to the forest-clearcut edge. Of 4 habitat-mapping methods evaluated, the method that incorporated timber volume strata and a wind disturbance-related aspect had greatest utility in identifying areas selected for or used disproportionately little by deer during the deep snow winter. We found that deer exhibited marked changes in habitat use during deep snow conditions compared to a low snow winter, and we agree with previous researchers that providing habitats selected by deer during deep snowfall is an important consideration in Sitka black-tailed deer habitat management.  相似文献   
4.
Secondary forests constitute a growing portion of forested areas worldwide. They might have a substantial role for the conservation of biodiversity in tropical areas, but there is little information on their potential to support forest species and the recovery of faunal communities. We studied two forest frogs (Eleutherodactylus diastema and E. fitzingeri) in an area of Costa Rica composed of a mosaic of primary forest, young secondary forest and pasture, and we compared the density of calling males in areas with different forest alteration. Autoregressive models were used to compensate for potentially undesired effects of spatial autocorrelation and pseudoreplication. Both species were most abundant in riparian, primary forest. However, E. fitzingeri was also abundant in riparian secondary forests, and its density far from the river was similar in primary and secondary forest, suggesting that river proximity can influence the recovery of secondary forest for amphibians. Conversely, the density of E. diastema was similar in secondary forest and pasture, stressing interspecific differences for recovery rate. These frogs have a keystone role in nutrient cycling and food webs, and their prompt recovery might represent an important step for the functional recovery of forests. Nevertheless, the strong interspecific differences stress the complexity of these processes.  相似文献   
5.
犬脑11只,经生理盐水冲洗脑血管后,注入20%钡胶液,切成0.2~1.0厘米的厚片,用显微X线法研究犬脑内各级动脉的构筑,其结果:1.皮质动脉的管径平均为25.9±0.005微米,平均长度为888.0±0.241微米。其形态与发出部位有关,分别呈栅状和瓶刷状。2.髓质动脉的管径平均为49.9±0.007微米。呈直线或孤形向心走行。3.皮质下动脉的管径平均为38.7±0.009微米。呈新月形或蟹钳状分布。4.豆纹动脉和内囊动脉的平均管径为70.0±0.021微米。呈锐角、反血流方向发自母干,再呈“S”形上升。5.丘脑动脉的平均管径为63.7±0.019微米,主要从下方进丘脑,呈树枝状分支。  相似文献   
6.
Recovery of headwater streams following the cessation of mining and the application of terrestrial (vegetative) reclamation techniques was assessed by comparison of water quality and aquatic biota in two such systems (reclaimed four to seven years) with that of an unimpacted stream and of streams draining mine areas which were abandoned without reclamation. Alkalinity, hardness, sulfate, and conductivity were elevated in the reclaimed mine streams as were fine-particle suspended solids and sediment. Overall water quality was comparable to streams draining unreclaimed lands. Benthic invertebrate and fish populations were significantly lower in abundance in the reclaimed mine streams than in the reference stream and showed less taxonomic richness and stability; they were similar in these respects to the biota of the unreclaimed mine streams. Continued sedimentation from mined areas and haul roads affected stream habitat and appeared to be the major factor limiting biotic recovery. These findings emphasize that terrestrial reclamation does not assure lotic restoration. Water quality criteria merit consideration in the refinement of reclamation procedures for mined lands.  相似文献   
7.
麻黄碱对兔主动脉和心房作用机制的研究   总被引:4,自引:0,他引:4  
麻黄碱(E,×10~(-4)—3.3×10~(-3)M)和去甲肾上腺素(NA,6×10~(-8)—6×10~(-5)M)均能引起离体兔主动脉条浓度依赖性收缩。可卡因能明显地增强 NA 的作用,但明显地减弱麻黄碱的作用,用可卡因后麻黄碱的作用为用可卡因前的10—92.6%。利血平处理后,麻黄碱和 NA的作用都明显增强,但利血平对前者的增强作用比后者更甚。在利血平处理及未处理肌条上,麻黄碱的作用均可被酚妥拉明阻断。麻黄碱(3.3×10~(-6)—3.3×10~(-5)M)和异丙肾上腺素(ISP,10~(-9)—10~(-5)M)均能引起离体兔心房率的增加。可卡因明显地减弱麻黄碱的这一作用,即为对照组的8.8—29.1%,但不影响 ISP 的作用。利血平处理后,麻黄碱对兔心房的作用也明显减弱,为对照纽的15.4—28.4%;而 ISP 作用则略增加。3×10~(-4)麻黄碱可明显增加[3~H]NA 从兔主动脉条的流出量,此作用在给药后5min内即开始,可持续30 min 以上。上述结果提示,对于兔主动脉和心房,麻黄碱兼具直接作用于效应器细胞和通过释放末梢中 NA 的间接作用;直接作用在主动脉占优势,间接作用在心房占优势。  相似文献   
8.
Closure of stomata by abscisic acid (ABA) was studied by floating leaf epidermal strips of Commelina communis L. in PIPES buffer (pH 6.8) containing a range of KCl concentrations. Control apertures were greatest at high concentrations of the salt, and the effects of ABA, in terms of closure, were most pronounced below 100 mol m-3 KCl. Stomata opened on strips floated on buffer plus 50 mol m-3 KCl and closed within 10 min when transferred to the same medium plus 0.1 mol m-3 ABA. [2-14C]ABA was used to study uptake and distribution of the hormone by the epidermal strips. It was calculated that no more than 6 fmol ABA were present per stomatal complex at the time of closure, although uptake continued thereafter. Microautoradiography indicated that radioactivity from [2-14C]ABA accumulated in the stomatal complex at or near the guard cells within 20 min. TLC was used to examine the state of the label after 1 h incubation. Efflux of label from preincubated tissue appeared to occur in three phases (t1/2=7.2 s, 4.0 min, 35.2 min). Efflux was correlated with stomatal re-opening. The results confirm that ABA can accumulate in the epidermis of C. communis.Abbreviation ABA Abscisic acid  相似文献   
9.
宠物疫病特别是人兽共患病严重危害着宠物健康和公共卫生安全。通过对我国宠物疫苗研发和应用现状进行分析,提出关于开展疫苗质量监控技术和免疫抗体检测技术研究,以建立宠物疫苗质量监控体系和免疫抗体监测体系的建议。免疫试纸快速检测技术是一种敏感、快捷的一步法检测技术,适用于多种分析物的快速、低成本即时检测。本实验室建立了抗原、抗体和半抗原3类靶标物的免疫试纸快速检测技术体系,研制成功动物疫病抗原、抗体快速检测试纸系列产品,真正实现了长期以来人们在检测技术领域所追求的"特异、敏感、快速、简便"的目标,为实现动物疫病快速诊断和实时监测提供技术支撑。  相似文献   
10.
The object of this study was to develop a simple, rapid, specific, and highly sensitive method to detect HCV core antigen. A nucleic acid aptamer was designed with the high specificity and sensitivity in a nucleic acid lateral flow strip to compete with HCV core antigen and DNA probes. The lower detection limit of the test strip was calculated to be 10 pg/mL with the scanner and 100 pg/mL with naked eyes. Results showed that there were no cross-interactions with other proteins such as HCV NS3, E1/E2 antigens, HIV p24 antigens, or BSA proteins (HCV unrelated protein). When the viral load exceeded 104 copies/mL, the positive coincidence rates of ELISA and strip detection, when compared with the HCV RNA assay, were 98.44% and 97.28%, respectively. The results indicated that the ELISA detection and strip assay were in good agreement with the measured value. The results indicated that a nucleic acid lateral flow strip was a simple, rapid, specific, highly sensitive, and cost-effective field-based method for detecting HCV core antigen. The strip assay is an acceptable alternative to diagnose HCV core antigen and to investigate its epidemiology in clinical laboratories lacking specialized equipment and skills.  相似文献   
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