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1.
水稻是我国主要粮食作物,每年都会因虫害造成大量的经济损失,为了挽回害虫造成的损失,必须对害虫进行防治。田间节肢动物群落调查是评价害虫防治效果的重要依据,取样方式对节肢动物群落调查的准确性具有重要的影响。另外,对转基因作物对稻田生物多样性安全性进行评价时,取样方式对多样性评价的准确性也具有重要的影响。本文采用吸虫器法、盆拍法和马氏网诱集法3种取样方式进行稻田节肢动物调查,并评估不同取样方式的采集效率。得到的结果有:1.采集到的节肢动物物种数:马氏网诱集法吸虫器法盆拍法;2.采集的节肢动物数量:盆拍法吸虫器法马氏网诱集法;3.吸虫器取样法在调查叶蝉科、秆蝇科、茧蜂科、姬蜂科、金小蜂科、缘腹细蜂科、蕈蚋科时,取样效率较高;4.盆拍取样法在调查叶蝉科、瘿蚊科、微蛛亚科、跳蛛科、狼蛛科、猫蛛科、弹尾虫目、飞虱科时,取样效率较高;5.马氏网诱集法在调查缟蝇科和毛蠓科时取样效率较高。马氏网诱集法善于采集具有飞行能力的节肢动物;吸虫器法对不同习性的节肢动物采集效果均较高;盆拍法适合采集活动于水稻基部的节肢动物。  相似文献   

2.
介绍运用微生物法测定保健食品中维生素B6的含量。GB/T5009.154—2003将微生物法规定为测定食品中维生素B6的国家标准方法Ⅲ。其原理为卡尔斯伯酵母菌需在有维生素B6存在的条件下才能生长,在一定条件下维生素B6的量与其生长量成正比关系。用分光光度仪在550nm波长下测定该菌的生长.与标准曲线相比较,从而得出该样品中维生素B6的含量。通过对国标方法作较详细的注解,并对有些地方作适当的修改,以期对需要开展此项工作的实验室及其人员会有较大的帮助。  相似文献   

3.
一种早期胚胎体外培养新方法的建立   总被引:5,自引:0,他引:5  
建立一种不依赖于液体石蜡的早期胚胎体外培养方法——套皿法,并比较了4种不同处理方法体外培养胚胎的效果。结果显示,采用套皿法进行胚胎培养,盖液体石蜡和不盖液体石蜡皿中的胚胎在各阶段的发育率差异不显著。与套皿法相比,用单皿微滴覆盖法(Brinster法)培养的胚胎在各阶段的发育率显著降低。不覆盖液体石蜡单皿中的胚胎则阻断于二细胞阶段。实验设计的套皿法是一种有效的早期胚胎体外培养方法,为早期胚胎体外培养提供了一种新方法。  相似文献   

4.
目的:探讨FISH实验中用直接涂片法、盐水制片法、TCT制片法、低渗滴片法制片法和宫颈切片组织取材方法对于FISH成功率的影响.方法:收集2008年3月至2009年3月青岛大学医学院附属医院妇科162例宫颈脱落细胞标本及2008年5月至2009年3月手术切除或活检的宫颈组织63例,用荧光原位杂交(FISH)方法检测hTERC基因.结果:直接涂片法、盐水制片法、生理盐水法、TCT制片法和石蜡包埋组织切片法hTERC基因杂交成功率分别为58.3%,65%,55%,87.1%,85.7%,TCT制片高于其它四组;低渗滴片法背景干净度、细胞形态、裸核数量满意度最高;TCT制片法细胞数量满意率最高;石蜡包埋组织切片法荧光信号满意率最高.结论:在检测hTERC基因的宫颈癌筛查中,TCT制片法明显优于其他方法,而在指导宫颈病变及宫颈癌的治疗中,石蜡包埋组织切片法的染色体破坏最小,实际意义更大.  相似文献   

5.
A method has been developed for the analysis of (14)CO(2) evolution from the mineralization of (14)C-labelled organic compounds in soil samples. The new method is less space demanding and substantially cuts down laborious manual work compared to the traditional incubation bottle method used. Furthermore, the use of scintillation cocktail is largely reduced with the new method. In the new method, (14)CO(2) is trapped in filter paper held in the lid of a 20 ml glass vial by surface tension. The trapping solution used is Ca(OH)(2), which fixates CO(2) in the filter paper and the analysis of trapped (14)CO(2) is done using the Cyclone trade mark Storage Phosphor system. The lids are placed in a 32 well holder and exposed to a phosphor screen prior to scanning in a Cyclone trade mark scanner. The new filter method has been tested and compared to results obtained using the traditional method. The results show good agreement but due to a smaller capacity for CO(2) with the filter method compared to the traditional method, the interval between sampling has to be shorter using the filter method when the CO(2) development is high. The detection limits for the filter method is higher compared to the traditional method. With the filter method, the level of radioactivity has to exceed 300 dpm before detection is possible, while the same limit for the traditional method is around 30 dpm. On the other hand, the gas trapping faster and the efficiency is higher with the filter method.  相似文献   

6.
The neighbor-joining method: a new method for reconstructing phylogenetic trees   总被引:673,自引:29,他引:673  
A new method called the neighbor-joining method is proposed for reconstructing phylogenetic trees from evolutionary distance data. The principle of this method is to find pairs of operational taxonomic units (OTUs [= neighbors]) that minimize the total branch length at each stage of clustering of OTUs starting with a starlike tree. The branch lengths as well as the topology of a parsimonious tree can quickly be obtained by using this method. Using computer simulation, we studied the efficiency of this method in obtaining the correct unrooted tree in comparison with that of five other tree-making methods: the unweighted pair group method of analysis, Farris's method, Sattath and Tversky's method, Li's method, and Tateno et al.'s modified Farris method. The new, neighbor-joining method and Sattath and Tversky's method are shown to be generally better than the other methods.   相似文献   

7.
改进的SDS-CTAB法提取濒危植物连香树总DNA   总被引:17,自引:0,他引:17  
对珍稀濒危植物连香树(Cercidiphyllum japonicum)的6种总DNA提取方法进行了对比试验,结果表明改进的SDS-CTAB法更适合于连香树总DNA提取。该方法提取的DNA经紫外消光值检测,其A260/A280为1.8532,优于CTAB法(1.4872)、SDS法(1.3552)、PVP法(1.5079)、尿素法(1.1858)和高盐低pH法(1.4534)。琼脂糖凝胶电泳和PCR扩增结果也得出同样的结论。  相似文献   

8.
Summary The p-dimethylamino-benzaldehyde method of Bomstein and Evans, the ninhydrin method of Marrelli and the new p-dimethyl-amino-benzaldehyde method of Kornfeld were evaluated for analysis of penicillin-V acylase and cephalosporin-V acylase in fermentation broths. The ninhydrin method was the method of choice for cephalosporin-V acylase, whereas the Kornfeld method had certain advantages with respect to penicillin-V acylase.  相似文献   

9.
为探索一个灵敏、简便、快速的定量检测A/C群脑膜炎球菌多糖疫苗中乳糖含量的方法,对两种化学法进行了分析和比较。两种化学方法分别采用间苯二酚显色法和苦味酸显色法。间苯二酚显色法为套用唾液酸测定法,苦味酸显色法是对乳制品中乳糖含量检测方法的改良。两种方法的相关系数均大于0.99,线性良好。用间苯二酚法测定样品的回收试验检测结果平均值和变异系数分别为100.4%和3.09%,用苦味酸法测定样品的回收试验检测平均值和变异系数分别为99.9%和1.43%。这两种方法可以初步应用于疫苗中乳糖含量检测。  相似文献   

10.
Zhang X  Shi L  Shu S  Wang Y  Zhao K  Xu N  Liu S  Roepstorff P 《Proteomics》2007,7(14):2340-2349
An improved method for sample preparation for MALDI-MS and MS/MS using AnchorChip targets is presented. The method, termed the SMW method (sample, matrix wash), results in better sensitivity for peptide mass fingerprinting as well as for sequencing by MS/MS than previously published methods. The method allows up-concentration and desalting directly on the mass spectrometric target and should be amenable for automation. A draw back caused by extensive oxidation of methionine and tryptophan in the SMW method can be alleviated by the addition of n-octyl glucopyranoside and DTT to the sample solution. The method was validated for protein identification from a 2-DE based liver proteome study. The SMW method resulted in identification of many more proteins and in most cases with a better score than the previously published methods.  相似文献   

11.
A simplified method for the treatment of tattoos is described. The method is based on an older method called the "French method" known to tattoo artists. The treatment consists of superficial dermabrasion of the skin followed by application of a tannic acid solution which is then "rubbed" into the skin by the dermabrasion wheel. The treatment site is then "painted" with a silver nitrate stick. A heavy eschar forms which separates in approximately 2 to 3 weeks. The method incorporates the use of equipment that is present in the usual plastic surgical office. The method has produced excellent improvement in tattoos, with obliteration of the tattoo in the majority of cases. This report covers 85 patients with 207 tattoos treated over an 11-year period. The method is presented as a treatment of tattoos that are too large for simple excision. Details of the treatment are presented.  相似文献   

12.
Ginther OJ 《Theriogenology》1993,39(2):363-371
A method was developed for ultrasonically characterizing follicular waves in heifers without the necessity of maintaining day-to-day identities of individual follicles (nonidentity method). Results were compared to a method in which the identities of individual follicles were maintained from day to day (identity method). Data collected daily during 5 estrous cycles were processed by each method, independently, by different operators. The nonidentity method involved grouping and then profiling follicles in order of decreasing diameters without regard to day-to-day identities. The profiling scheme distinguished between follicles of the left versus the right ovary. The dominant and subordinate follicles were readily distinguishable in the nonidentity profiles. When successive dominant follicles developed in the opposite ovary, the follicles were profiled directly. When two successive dominant follicles developed on the same ovary, size information was obscured for a few days where the profiles for each follicle crossed, but continuity of the profiles on each side of the area of ambiguity was maintained. The nonidentity method seemed equivalent to the identity method in determining characteristics of the dominant follicle (e.g., maximal diameter, growth rate, regression rate). Day of emergence of a wave and day of divergence in diameters between dominant and subordinate follicles were readily determined by inspection of the nonidentity profiles. A greater number of subordinate follicles per wave was detected by the nonidentity method due to the inability to individually identify all detected follicles by the identity method. Regression of follicles from a previous wave into the subordinate follicles of a succeeding wave was apparent by either method. The nonidentity method seemed suitable for most needs, was less tedious, and required less skill than the identity method.  相似文献   

13.
A simple and sensitive spectrophotometric method for measuring lipid peroxides and peroxides in general is described. The method was developed by modifying an existing method based on the peroxidase activity of hemoglobin with tetramethylbenzidine as the electron donor. The modifications resulted in much improved sensitivity and reproducibility. With the modified method lipid peroxides as low as 2 nmol can be measured, a high sensitivity compared with other spectrophotometric methods. The absorbance is linear over a wide range of concentrations. It is suggested that this modified method in combination with the commonly used thiobarbituric acid method will give a better quantitation of lipid peroxidation.  相似文献   

14.
演化极端结合分支分类方法   总被引:1,自引:1,他引:0  
从生物演化的逆方向考虑,提出一种聚合的分支分类运算方法,称为演化极端结合分支分类法。文章阐明其设计思路、演算步骤,并以实例具体说明其演算过程。最后以演化长度系数、合理解与合理方法等概念,对演化极端结合法进行评价。  相似文献   

15.
Measurement of DNA with an automatic spectrophotometer   总被引:2,自引:0,他引:2  
A method that uses an automated spectrophotometer to read microtiter plates in a modification of the diphenylamine method of DNA determination in tissue extracts, is presented. The micromethod saves technician time, and reduces exposure to acetic acid fumes. The reproducibility of the method is superior to the manual method. Fewer pipetting steps are required, and the method is suited to large batches of samples.  相似文献   

16.
啮齿动物的巢区面积估算法   总被引:10,自引:5,他引:5  
巢区(Home range)是动物在其巢附近进行取食、生殖、育幼等日常活动的区域(Burt 1940)。标志流放法是应用最广的调查啮齿动物巢区的方法,尤其是按方格式布笼。但对同一野外调查结果,由于估算方法不同,巢区估算值相差很大,并且至今尚无学者提出一致公认的估算法。1980年5-10月,我们在青海省门源县的高寒草甸生态系统定位站调查根田鼠的巢区,按多种估算法对同一批实际调查结果估计了巢区面积,并对结果进行了分析比较,检查其特点和优缺点,并提出修正平均值法,作为我们今后讨论根田鼠巢区动态的基础。 对方格式布笼的调查结果进行巢区的估算方法,基本上分二大类,图形法和概率性模型法。图形法是按照捕点分布划出巢区,并直接求出巢区面积,如最小面积法,包括或不包括周边地带法,最大距离法和复合散布图法。  相似文献   

17.
大尺度估算森林生物量一直是人们关注的焦点,而构建林分水平的生物量模型是一种估算森林乔木层生物量的方法。本研究基于聚合法1、聚合法2、平差法、分解法构建红松人工林林分生物量模型,并对比分析4种可加性方法的预测精度,为黑龙江省红松人工林的生物量预测提供科学依据。各模型均使用权函数来消除各模型的异方差,并以留一交叉验证法(LOOCV)作为各模型的检验方法。结果表明: 平差法的整体预测能力略优于聚合法1、聚合法2和分解法,预测精度排序为平差法>聚合法1>聚合法2>分解法;分别对比不同林分断面积的预测能力时,4种可加性方法的预测精度不一致。当红松人工林的林分断面积分布于0~10或50~60 m2·hm-2区间时,建议采用分解法的参数估计值,而林分断面积分布于其他区间时,建议采用平差法的参数估计值。  相似文献   

18.
The enzymatic method for the determination of ammonia with glutamate dehydrogenase has been adapted to the AutoAnalyzer. The automated method was applicable for NH3 measurement in sheep rumen samples, swine gut fluid samples, and bovine plasma. Results were compared with those of the Conway diffusion method and the manual enzymatic method. The automated method allows 30 samples per h to be analyzed routinely. Values were comparable with those with the manual method, but lower than those with the Conway diffusion method.  相似文献   

19.
Feenstra B  Skovgaard IM  Broman KW 《Genetics》2006,173(4):2269-2282
The Haley-Knott (HK) regression method continues to be a popular approximation to standard interval mapping (IM) of quantitative trait loci (QTL) in experimental crosses. The HK method is favored for its dramatic reduction in computation time compared to the IM method, something that is particularly important in simultaneous searches for multiple interacting QTL. While the HK method often approximates the IM method well in estimating QTL effects and in power to detect QTL, it may perform poorly if, for example, there is strong epistasis between QTL or if QTL are linked. Also, it is well known that the estimation of the residual variance by the HK method is biased. Here, we present an extension of the HK method that uses estimating equations based on both means and variances. For normally distributed phenotypes this estimating equation (EE) method is more efficient than the HK method. Furthermore, computer simulations show that the EE method performs well for very different genetic models and data set structures, including nonnormal phenotype distributions, nonrandom missing data patterns, varying degrees of epistasis, and varying degrees of linkage between QTL. The EE method retains key qualities of the HK method such as computational speed and robustness against nonnormal phenotype distributions, while approximating the IM method better in terms of accuracy and precision of parameter estimates and power to detect QTL.  相似文献   

20.
Upon plotting of areas against optical densities in immunocytochemically stained tissue sections, hyperbolic curves were obtained which could be reduced to two straight lines, one representing variations in stained structures, and the other variations in background. The slopes of the stained structure lines reflected staining intensity independently of total area of stained structure in a section. The ratio of slopes of the stained structure and background lines reflected immunocytochemical sensitivity. A comparison of the peroxidase-antiperoxidase (PAP) method with the avidin-biotin complex (ABC) method showed that at usual antibody dilutions the PAP method was much more sensitive than the ABC method, while at impractically high antibody dilutions it was moderately more sensitive. Once sufficient dilutions of antibodies were reached, staining intensities dropped sharply with the PAP method. On the other hand, the dilution curves were flat with the ABC method. The ABC method consequently appeared unsuitable for estimating variations in concentration of antigen or for distinguishing high or low concentrations of antigen. The ABC method provided a stain for myelin even in the absence of any antibodies.  相似文献   

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