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1.
《Forensic science》1978,11(1):115-121
A rapid, simple, reproducible and relatively inexpensive electrophoretic technique for displaying the structural proteins of hair is described. Hairs from a large number of individuals were examined and a number of distinct differences are presented.The possibility of using these individual differences as a means of individual identification is discussed.  相似文献   

2.
Eumelanins are brown-black pigments present in the hair and in the epidermis which are acknowledged as protection factors against cell damage caused by ultraviolet radiation. The quantity of eumelanin present in hair has recently been put forward as a means of identifying subjects with a higher risk of skin tumours. For epidemiological studies, chromatographic methods of determining pyrrole-2,3,5-tricarboxylic acid (PTCA; the principal marker of eumelanin) are long, laborious and unsuitable for screening large populations. We suggest near infrared (NIR) spectroscopy as an alternative method of analysing eumelanin in hair samples. PCTA was determined on 93 samples of hair by means of oxidizing with hydrogen peroxide in a basic environment followed by chromatographic separation. The same 93 samples were then subjected to NIR spectrophotometric analysis. The spectra were obtained in reflectance mode on hair samples which had not undergone any preliminary treatment, but had simply been pressed and placed on the measuring window of the spectrophotometer. The PTCA values obtained by means of HPLC were correlated with the near infrared spectrum of the respective samples. A correlation between the PTCA values obtained by means of HPLC and the PTCA values obtained from an analysis of the spectra was obtained using the principal component regression (PCR) algorithm. The correlation obtained has a coefficient of regression (R(2)) of 0.89 and a standard error of prediction (SEP) of 13.8 for a mean value of 108.6 ng PTCA/mg hair. Some considerations about the accuracy of the obtained correlation and the main sources of error are made and some validation results are shown.  相似文献   

3.
The basis of genetic monitoring is the knowledge of laws of the spontaneous mutation process. These laws are determined for human chromosome and genome mutations by cytogenetic examination of newborns, infants with congenital defects, and the material of spontaneous abortions. Confidence intervals and all the necessary sample sizes were calculated when registering the mutagenic effects of different intensity in the general population as well as to the groups of closer contact with mutagens. Such calculations were made for controlling the spontaneous mutation process in lymphocytes of human peripheral blood on the basis of registering chromosome aberrations.  相似文献   

4.
The extent of environmental pollution and resulting human exposure to hazardous toxic chemicals in the environment is often difficult to assess. One of the possible alternative approaches to this problem is the use of the biological indicators to demonstrate environmental pollution. This approach appears to be particularly suitable for demonstrating exposure to potentially toxic trace elements. In addition to analyses of plant and animal specimens the element content of human hair as an indicator of exposures to arsenic, mercury, cadmium, lead, antimony, manganese, nickel and cobalt has been repeatedly confirmed as reliable, provided the analyses were carried out and evaluated on group diagnostic basis and were done in groups of individuals occupationally not exposed to these metals. Preferably groups of 10-year-old children are to be used when only environmental pollution is to be taken into account. Hair samples are incomparably easier to collect, transport and store than the alternative biological material such as blood and urine used commonly to demonstrate exposure to various toxic agents. Biological monitoring of environmental pollution cannot replace the standard procedures of measuring air, water and soil pollution; however, the technique appears to have the potential of being an effective tool search for the extent of environmental pollution and for delimitation of territorial boundaries of areas affected most by hazardous emissions containing potentially toxic trace elements.  相似文献   

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6.
Summary Surveying the chemical pollution status of a given area is increasingly becoming the task of biological indicators, ie animal and plant organisms capable of providing us with the necessary data. For example, in the wake of certain contaminations, they may increase or decrease in number, vary population proportions in relation to given traits, become vectors of certain toxic molecules or heavy metals, or accumulate them in their bodies or in their «products». The advantage of bioindicators over chemical or physical detectors is their ability to supply extensive — both spatially and temporally —rather than limited and instantaneous data, thus making such information more representative. In many instances the bioindicator takes samples for us-a service that is undoubtedly valuable even though it must be linked to a sound knowledge of the organism's ethogram and biology so as to arrive at a scientifically legitimate interpretation of the data provided.  相似文献   

7.
Efficient tools for on-line and in situ monitoring of environmental pollutants are required to provide early warning systems. In addition, such tools can contribute important information on the progress of various remediation treatments. One of the recently developed monitoring technologies involves the use of whole-cell biosensors. Such biosensors could be constructed to detect general toxicity or specific toxicity caused by one or more pollutants. Currently, a large spectrum of microbial biosensors have been developed that enable the monitoring of pollutants by measuring light, fluorescence, color or electric current. Electrochemical monitoring is of special interest for in situ measurements as it can be performed using simple, compact and mobile equipment and is easily adaptable for on-line measurements. Here we survey the potential application of electrochemical biosensors in monitoring of general toxicity as well as hydrocarbons and heavy metals.  相似文献   

8.
新型吡唑类化合物DL-1的硝化抑制效应初探   总被引:22,自引:0,他引:22  
安丽  曹同  俞鹰浩 《生态学杂志》2006,25(2):201-204
以国内外应用较为广泛的硝化抑制剂双氰胺(DCD)为参比对象,采用室内培养方法,对新型吡唑类化合物DL-1的硝化抑制效应进行初步探讨.结果表明,DL-1对土壤中铵的氧化过程具有显著的抑制效应,前3周的硝化抑制率可达70%以上,且硝化抑制能力在第14天至28天最强.与等量DCD相比,施用量为(NH4)2SO4氮量1.0%的DL-1在14、21和28 d使土壤中的NO3--N含量分别下降 26.23%、33.27%和23.31%;与不加抑制剂的对照处理相比,土壤NO3--N含量则分别下降了71.12%、69.10%和55.14%.当DL-1用量为(NH4)2SO4氮量的2。0%时,土壤的硝化作用受到了更强烈的抑制,到培养第90天试验结束,土壤中的NO3--N含量始终维持在较低水平.  相似文献   

9.
A novel application of distance-based topological indices : Wiener (W)-, Szeged (Sz)-, Padmakar-Ivan (PI)-, and Sadhana (Sd)-indices in modeling electronic absorption bands of arene absorption spectra has been described. It is demonstrated that all these indices correlate linearly with the logarithm of beta and para electronic absorption bands in several series of arene systems. The results have shown that our methodology is best suited for the estimation--lnlambda(beta), while comparatively less significant results are obtained in case of the estimation of lnlambda(p). The statistical analysis of the data have shown that PI index gives better results for modeling lnlambda(beta); while Sz index proved better for modeling lnlambda(p). The results are critically discussed on the basis of regression parameters and quality of correlation. Such a study will be useful as a tool for modeling toxicity of arene system as well as their environmental pollution.  相似文献   

10.
In response to ever-increasing anthropogenic changes to natural ecosystems, regional, national and international organizations have established guidelines for monitoring biological diversity. Most monitoring programs, however, do not take full advantage of the potential afforded by molecular genetic markers, which can provide information relevant to both ecological and evolutionary time frames, while costing less and being more sensitive and reliable than traditional monitoring approaches. As several molecular and computational approaches are relatively new, many technical and theoretical issues remain to be resolved. Here, we illustrate how DNA and population genetic data can provide valuable information, often unattainable via other approaches, for monitoring species of management, conservation and ecological interest.  相似文献   

11.
Both acute nephritis and chronic nephritis account for substantial morbidity and mortality worldwide, partly due to the lack of reliable tools for detecting disease early and monitoring its progression non‐invasively. In this work, Raman spectroscopy coupled with multivariate analysis are employed for the first time to study the accelerated progression of nephritis in anti‐GBM mouse model. Preliminary results show up to 98% discriminant accuracy for the severe and midly diseased and the healthy among two strains of mice with different susceptibility to acute glomerulonephritis. This technique has the potential for non‐invasive or minimally‐invasive early diagnosis, prognosis, and monitoring of renal disease progression.

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12.
Microbial biosensors are compact, portable, cost effective, and simple to use, making them seem eminently suitable for the in situ monitoring of environmental pollution. One promising approach for such applications is the fusion of reporter genes with regulatory genes that are dose-dependently responsive to the target chemicals or physiological signals. Their biosensor capabilities, such as target range and sensitivity, could be improved by modification of regulatory genes. Recent uses of such genetically engineered microbial biosensors include the development of portable biosensor kits and high-throughput cell arrays on chips, optic fibers, or other platforms for on-site and on-line monitoring of environmental pollution. This mini-review discusses recent advances in microbial biosensors and their future prospects, with a focus on the development and application of genetically modified microbial biosensors for in situ environmental monitoring.  相似文献   

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14.
Efforts to follow tumor-specific immune responses in patients are often thwarted by lack of knowledge of the appropriate tumor antigens and the CTL epitopes of those antigens. There is, therefore, a growing need for techniques to monitor tumor-specific immune responses in settings where tumor antigens, and antigenic epitopes, remain unidentified. Here we describe a novel system to follow tumor-specific CTL immune responses. A truncated, soluble murine class I MHC (H-2Db) molecule was fused with a rat IgG2a Fc, in order to allow secretion of the complex. Tumor-specific CTL could then be detected as a result of the complex fastening to specific T cell receptors (TCR). These constructs were inserted into the genome of a recombinant adenovirus vector. Infection of tumor cells with these adenovirus constructs results in the secretion of the complexes into the culture supernatant. These soluble divalent class I MHC molecules were used to detect and activate specific CTL populations.  相似文献   

15.

Background

Human African trypanosomiasis (HAT) or sleeping sickness leads to a complex neuropsychiatric syndrome with characteristic sleep alterations. Current division into a first, hemolymphatic stage and second, meningoencephalitic stage is primarily based on the detection of white blood cells and/or trypanosomes in the cerebrospinal fluid. The validity of this criterion is, however, debated, and novel laboratory biomarkers are under study. Objective clinical HAT evaluation and monitoring is therefore needed. Polysomnography has effectively documented sleep-wake disturbances during HAT, but could be difficult to apply as routine technology in field work. The non-invasive, cost-effective technique of actigraphy has been widely validated as a tool for the ambulatory evaluation of sleep disturbances. In this pilot study, actigraphy was applied to the clinical assessment of HAT patients.

Methods/Principal Findings

Actigraphy was recorded in patients infected by Trypanosoma brucei gambiense, and age- and sex-matched control subjects. Simultaneous nocturnal polysomnography was also performed in the patients. Nine patients, including one child, were analyzed at admission and two of them also during specific treatment. Parameters, analyzed with user-friendly software, included sleep time evaluated from rest-activity signals, rest-activity rhythm waveform and characteristics. The findings showed sleep-wake alterations of various degrees of severity, which in some patients did not parallel white blood cell counts in the cerebrospinal fluid. Actigraphic recording also showed improvement of the analyzed parameters after treatment initiation. Nocturnal polysomnography showed alterations of sleep time closely corresponding to those derived from actigraphy.

Conclusions/Significance

The data indicate that actigraphy can be an interesting tool for HAT evaluation, providing valuable clinical information through simple technology, well suited also for long-term follow-up. Actigraphy could therefore objectively contribute to the clinical assessment of HAT patients. This method could be incorporated into a clinical scoring system adapted to HAT to be used in the evaluation of novel treatments and laboratory biomarkers.  相似文献   

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17.
Generalized Procrustes analysis (GPA) is a multivariate technique that involves transformations of data matrices to provide optimal comparability. We propose GPA to quantify the concordance among sets of variables that characterize natural, human and productive subsystems. When the land use fits in with the physical support of agricultural production, people's well-being should be evident in a high concordance between the land use and the social conditions. In a situation of instability each set of variables operates in diverse directions resulting in lower resilience and sustainability. Two GPA were performed, between physical support and land use data sets (concordance = 67.4%), and between land use and social conditions data sets (concordance = 65.3%). The interplay between the pair of concordance values constitutes a bi-dimensional index which serves as an ecological indicator. Based on bootstrap confidence interval, the 49 counties of the Pampa Ecoregion, Argentina, were classified in medium, high or low concordance. The lack of concordance is an indicator of imbalances which may contribute to guide environmental management.  相似文献   

18.
With high sensitivity and reproducibility, selected reaction monitoring (SRM) has become increasingly popular in proteome research for targeted quantification of low abundance proteins and post translational modification. SRM is also well accepted in other mass-spectrometry based research areas such as lipidomics and metabolomics, which necessitates the development of easy-to-use software for both post-acquisition SRM data analysis and quantification result validation. Here, we introduce a software tool SRMBuilder, which can automatically parse SRM data in multiple file formats, assign transitions to compounds, match light/heavy transition/compound pairs and provide a user-friendly graphic interface to manually validate the quantification result at transition/compound/sample level. SRMBuilder will greatly facilitate processing of the post-acquisition data files and validation of quantification result for SRM. The software can be downloaded for free from http://www.proteomics.ac.cn/software/proteomicstools/index.htm as part of the software suite ProteomicsTools.  相似文献   

19.
Environmental enrichment is an important tool utilized to improve animal welfare in zoological institutions through opportunity for mental and physical stimulation. Many past studies have focused on the impact enrichment has on animal behavior; however, none have conducted preference assessments on enrichment items to examine the relationship between animals' preferences and interaction with enrichment over a 24-hr period. Ten-minute free operant, paired-choice preference assessments were implemented in Study 1 to determine the enrichment preferences of African lions (N = 3). Following Study 1, Study 2 was conducted, which examined the behavior of African lions with enrichment items over the course of 30, 24-hr trials to evaluate the relationship between preferences established in Study 1 and long-term interaction with the enrichment. Generalized estimating equations revealed a statistically significant relationship between the percentage of time the enrichment was approached first and the average duration of interaction in Study 1 to the total duration of interaction and the percent of hours interacted with the item in Study 2. Additionally, the first 2 min of the preference data resulted in comparable statistically significant findings, demonstrating shorter preference assessments can produce similar results. The results support our prediction that preference assessments can be used to estimate the amount of interaction with enrichment over the course of time, with preferred items being interacted with more frequently and in longer duration. Information gained from this study suggests preference assessments can be a time and cost-effective tool to evaluate enrichment preference and predicted efficacy.  相似文献   

20.
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