共查询到20条相似文献,搜索用时 15 毫秒
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Morita Y Maruyama S Kabeya H Boonmar S Nimsuphan B Nagai A Kozawa K Nakajima T Mikami T Kimura H 《Microbiology and immunology》2004,48(7):527-533
Prevalence of Arcobacter spp. in chicken meat samples and environmental water samples in Japan and Thailand was investigated. Arcobacter was isolated from 48% of chicken meat samples (20/41) and 23% of river water samples (4/17) from Japan, and 100% of chicken meat samples (10/10) and 100% of canal water samples (7/7) from Thailand. A. butzleri was among the species isolated from all positive samples. About 10% genetic diversity was seen in the rpoB-rpoC in Arcobacters, and phylogenetic trees were divided into two clusters. In both countries, the results suggested that chicken and environmental water were highly contaminated with a genetically diverse population of Arcobacter. 相似文献
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Carlos Bouza 《Biometrical journal. Biometrische Zeitschrift》1995,37(4):497-506
A superpopulation model generates the probabilities of a Bernouilli random variable. The ranks of the involved variables are considered as survey weights. The distribution f each linear rank statistic is derived under the null hypothesis for the two sample problem and for the case k2 when a simple random sampling or stratified sampling is used. The growth of a population of insects and the behavior of patients with imsomnia are studied using these procedures. 相似文献
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Declines in shark populations worldwide are of particular concern to fishery managers and conservation biologists. Molecular-based technologies provide an efficient means to collect basic life-history information and estimates of dispersal that are critical to management. A novel method for obtaining high quality mtDNA from shark jaws and teeth for shark population genetic studies is described. 相似文献
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Roberto Cesareo 《Biological trace element research》1987,13(1):371-382
An X-ray fluorescence method for in vitro analysis of trace elements is presented. The method is characterized by the use
of an X-ray tube with secondary targets as a quasimonoenergetic radiation source, and by “infinitely thin” specimens.
Different aspects have been examined in order to optimize the sensitivity of the method. It is extremely important to use
secondary targets as pure as possible and collimators internally covered by the same element as the secondary target. It is
also important to reduce the contribution at the XRF spectrum of photons scattered by the sample, by the sample support, and
by the air.
Preconcentration techniques can conveniently also be used to this purpose. In this work, biological samples are preconcentrated
by reducing them to ash.
Typical sensitivities obtained are in the order of 1–5 ng/cm2 in a counting time of 103 s for elements with atomic number ranging from 24 (chromium) to 40 (zirconium). 相似文献
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A diver-operated coring system which takes undisturbed contiguous samples has been developed. A perspex space-frame localises a number of contiguous thin-walled tubes which can be driven into the sediment and from which core samples can be extracted. The corer consists of transparent tubing and low-pressure gate valve. The system is useful for describing small-scale spatial dispersion and for sampling patchy habitats. It is light, simple, inexpensive and is flexible with respect to the size and number of contiguous cores. 相似文献
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Follador MJ Yonamine M de Moraes Moreau RL Silva OA 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,811(1):37-40
In the present work, a semi-quantitative method was developed to detect simultaneously cocaine (COC) and cocaethylene (CE) (transesterification product of the coingestion of COC with ethanol) in sweat. Sweat samples were collected by means of a non-occlusive sweat patch device supplied by PharmChek. The method was based on the dissolution of COC and CE incorporated into the patch, with 0.2 M sodium acetate buffer (pH 5.0) and the extraction of the analytes by solid-phase microextraction (SPME). Gas chromatography/mass spectrometry (GC-MS) was used to detect the analytes in selected ion monitoring mode (SIM). The method showed to be very simple, rapid and sensitive. The limits of detection were 5 ng/ml for COC and CE (12.5 ng/patch). Good inter and intra-assay precision was also observed (coefficient of variation <8%) with the use of deuterated internal standards. 相似文献
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Summary A corer is described for sampling peats to a depth of 1 m with minimum disturbance of the sample. The instrument is simple and inexpensive to construct and is suitable for routine sampling operations. 相似文献
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用白色念珠菌临床分离株免疫家兔并经纯化获得特异性抗体,建立了检测临床标本中白色念珠菌抗原的ELISA一步法,此法的敏感性为99%,特异性为983%,与其它念珠菌和临床常见细菌均无交叉反应,整个反应只需1小时即可完成,可望成为一种取代培养法的快速诊断方法 相似文献
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S. Mousavi-Yeganeh 《Biological trace element research》1987,12(1):433-433
The object of this article is to apprise physicians and chemists of nuclear analytical techniques and, in particular, of ion
beam analysis (PIXE and PIGE) for the purpose of application to the clinical diagnostic method.
The feasibility of the technique, sampling, and sample preparation for trace element analysis in biological and biomedical
samples has been described previously (1–3). Analysis data from normal human blood samples and biomedical samples by ion beam
reactions have been compared at the end.
Emphasis will be placed on the use of the analytical technique on determination of the range of trace and toxic elements in
human blood samples. 相似文献
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J. Likeš 《Biometrical journal. Biometrische Zeitschrift》1987,29(3):313-321
The sequential procedure for testing up to k upper outliers proposed by Kimber (1982) for one-parameter exponential distribution is modified to a two-parameter exponential distribution. Further null distributions of some test statistics for an upper outlier-pair in a complete or censored sample from a two-parameter exponential distribution are given. Percentage points of the statistic T1 are tabulated. 相似文献
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A new sampler for extracting undisturbed surface peat cores for growth pot experiments 总被引:1,自引:0,他引:1
The sampler extracts uncompressed cores of 13·3 cm in diameter, up to 70 cm long, from the surface layers of peat. It has two close-fitting concentric cylindrical tubes, the outer one acting as a cutter and the inner one as a collector. As the outer tube is introduced by rotation into the peat, the cut core is collected in the inner tube which is maintained in a fixed position during the rotation phase and then pushed down stepwise. This limits friction between the peat core and the wall of the corer and prevents compression or distortion of the peat. These problems are also reduced by means of three skew cutters allowing the peat to be supported during the slicing action. Air can penetrate between the tubes to the lower end of the core, suppressing any suction effect during withdrawal. The sampler has been tested and has worked satisfactorily in many different peat types. 相似文献
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Hyötyläinen T Riekkola ML 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,817(1):13-21
This review provides an overview of the on-line coupling of solid-phase extraction or liquid chromatography with gas chromatography for the analysis of biological samples. Principles relevant to techniques are briefly presented and selected applications are described. Benefits of the coupled systems are discussed. 相似文献
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A new generation of spectrophotometers able to measure a wide range of absorbance in microliter aliquots is currently used for the determination of DNA, RNA, and proteins. The object of this article is to show that these instruments could be easily adapted for routine evaluation of enzymes and metabolites in 1–2-μl volumes of biological samples. 相似文献
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基因芯片技术在环境微生物群落研究中的应用 总被引:2,自引:0,他引:2
基因芯片技术作为一种快速、敏感、高通量的检测技术,近几年来在环境微生物群落研究中的应用越来越广泛并且得到充分的发展.它不仅可以研究环境微生物群落的微生物分布、种类、功能、动力学变化,还能分析环境污染等环境因素改变对其微生物生态的影响.本文按照基因芯片探针的设计方法,将环境样品群落研究基因芯片分为系统寡核苷酸芯片、功能基因芯片、群落基因组芯片、宏基因组芯片,并简要综述了该技术在活性污泥、土壤、水等环境样品微生物群落研究上的应用,最后,本文展望了该技术的研究方向和在寻找不同环境微生物群落之间差异微生物、差异基因或差异表达基因研究中的应用前景. 相似文献
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Analysis of variance (ANOVA) and log-linear analyses of time-budget data from a study of sloth bear enclosure utilization are compared. Two sampling models that plausibly underlie such data are discussed. Either could lead to an analysis of variance, but only one to a log-linear analysis. Given an appropriate sampling model and appropriate data, there is much to recommend log-linear analysis, despite its unfamiliarity to most animal behaviorists. One need not worry whether distribution assumptions are violated. Moreover, the data analyzed are the data collected, not estimates derived from those data, and thus no power is lost through a data reduction step. No matter what analysis is used, effect size should be taken into consideration. Multiple R2 can be used for ANOVA, but no directly comparable statistic exists for log-linear analyses. One possible candidate for a log-linear R2 analog is discussed here, and appears to give sensible and interpretable results. © 1992 Wiley-Liss Inc. 相似文献