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1.
The paper reviews general cognitive ability (g), the ways of its measurement, and genetic and behavioural aspects of its investigations. The criteria for assessment of cognitive abilities in animals are also suggested and described. Based on these criteria the new behavioural methods and procedures are developed for investigation of general cognitive ability.  相似文献   

2.
Different procedures have been developed to assess the functions of spermatozoa in terms of their motility as well as their fertilizing potential. The procedures for assessment of motility are either qualitative or quantitative, subjective or objective, while the procedures for assessment of fertilizing potential are either direct or indirect. In this review, the information available on the procedures are compiled and analysed including the procedures forin vitro penetration of zona-free hamster eggs by human or non-human primate spermatozoa.  相似文献   

3.
A specific assay method for radiolabelled digoxin and its known apolar metabolites in plasma, urine and saliva was developed. The assay permits the delineation of the pharmacokinetics of digoxin and its metabolites after single-dose administration of the drug to humans. Column chromatographic and solvent extraction procedures were used for the separation of apolar and polar compounds. Thin-layer chromatography was applied for the individual and specific assessment of digoxin and its apolar metabolites. Apolar and polar standards were used for quantitative assessments of all the procedures used. Accuracy and precision of the assay developed were evaluated in plasma, urine and saliva using biological samples spiked with known amounts of standards and by measuring replicates of biological samples obtained from pharmacokinetic studies with digoxin administration to humans.  相似文献   

4.
Inadequate tissue perfusion is a key contributor to early complications following reconstructive procedures. Accurate and reliable intraoperative evaluation of tissue perfusion is critical to reduce complications and improve clinical outcomes. Clinical judgment is the most commonly used method for evaluating blood supply, but when used alone, is not always completely reliable. A variety of other methodologies have been evaluated, including Doppler devices, tissue oximetry, and fluorescein, among others. However, none have achieved widespread acceptance. Recently, intraoperative laser angiography using indocyanine green was introduced to reconstructive surgery. This vascular imaging technology provides real-time assessment of tissue perfusion that correlates with clinical outcomes and can be used to guide surgical decision making. Although this technology has been used for decades in other areas, surgeons may not be aware of its utility for perfusion assessment in reconstructive surgery. A group of experts with extensive experience with intraoperative laser angiography convened to identify key issues in perfusion assessment, review available methodologies, and produce initial recommendations for the use of this technology in reconstructive procedures.  相似文献   

5.
Explicit, quantitative procedures for identifying biodiversity priority areas are replacing the often ad hoc procedures used in the past to design networks of reserves to conserve biodiversity. This change facilitates more informed choices by policy makers, and thereby makes possible greater satisfaction of conservation goals with increased efficiency. A key feature of these procedures is the use of the principle of complementarity, which ensures that areas chosen for inclusion in a reserve network complement those already selected. This paper sketches the historical development of the principle of complementarity and its applications in practical policy decisions. In the first section a brief account is given of the circumstances out of which concerns for more explicit systematic methods for the assessment of the conservation value of different areas arose. The second section details the emergence of the principle of complementarity in four independent contexts. The third section consists of case studies of the use of the principle of complementarity to make practical policy decisions in Australasia, Africa, and America. In the last section, an assessment is made of the extent to which the principle of complementarity transformed the practice of conservation biology by introducing new standards of rigor and explicitness.  相似文献   

6.
This essay is to provide my personal view of lipidomics for precision medicine and lipid metabolism on its experimental procedures, inherent limitations, assessment of cross-platform reproducibility, available resource, and future challenges. This article is part of a Special Issue entitled: BBALIP_Lipidomics Opinion Articles edited by Sepp Kohlwein.  相似文献   

7.
Over the past decade, risk assessment has become increasingly relied upon for helping to make environmental management decisions. This trend has been accompanied by research and refinements in basic risk assessment methodologies to improve our ability to understand and evaluate the human health risks associated with chemical exposures.Despite this progress, significant uncertainties continue to be associated with the risk assessment process. These uncertainties typically derive from gaps in available data regarding chemical toxicity, and from difficulties in reliably estimating the magnitude of chemical exposures. Given these limitations, risk assessment is generally most valuable in evaluating relative risk; for example, when comparing alternatives to achieving a specified goal, setting priorities for protecting human health, or establishing procedures for properly allocating resources. Risk assessment can also be useful for developing regulatory benchmarks such as permit limits for air or water. In many cases, however, the limitations of the risk assessment process make it difficult (if not impossible) to reliably estimate an absolute level of risk, especially for a specific individual in an exposed population. In such cases, risk assessment can be seriously misapplied, and its results misinterpreted.This paper discusses some of the challenges that have been faced by the field of risk assessment during the 1990s. Current trends in risk assessment, and its use by regulatory agencies in making risk management decisions, are also described.  相似文献   

8.
A brief overview of the design of the Women's Health Initiative (WHI) clinical trial and observational study is provided along with a summary of results from the postmenopausal hormone therapy clinical trial components. Since its inception in 1992, the WHI has encountered a number of statistical issues where further methodology developments are needed. These include measurement error modeling and analysis procedures for dietary and physical activity assessment; clinical trial monitoring methods when treatments may affect multiple clinical outcomes, either beneficially or adversely; study design and analysis procedures for high-dimensional genomic and proteomic data; and failure time data analysis procedures when treatment group hazard ratios are time dependent. This final topic seems important in resolving the discrepancy between WHI clinical trial and observational study results on postmenopausal hormone therapy and cardiovascular disease.  相似文献   

9.
Risk assessment models commonly used in contaminated sites employ a simple integration procedure by only partially combining exposure pathways from surface soil with vapor pathways from subsurface soil being excluded in the combination. The simplified approach can approximate the integrated generic assessment criteria only when there is a dominant exposure pathway. But these models are often based on a simple partitioning of a chemical in soil between the sorbed, dissolved, and vapor phases without consideration of the presence of non-aqueous phase liquid, and critically fail to consider non-soil background exposure for non-carcinogenic compounds. As a result, the generic assessment criteria derived may not be considered protective of human health. This article describes analytical integration procedures for the derivation of the generic assessment criteria that consider non-soil background exposure while limiting the average daily exposure for vapor pathways calculated from soil saturation limits. Significance of consideration of soil saturation limits for the derivation of the generic assessment criteria using an integrated approach is illustrated for organic compounds having varied levels of background exposure and soil saturations. The analytical integration procedures for the derivation of the soil generic assessment criteria under the linear chemical partition approach are also reviewed aiming to provide a single source of complete integration procedures for the derivation of the integrated generic assessment criteria.  相似文献   

10.
11.
The study of the biotransformation of a new synthetic drug 2,5-dimethoxy-4-bromamphetamine (DOB) and identification of its metabolites in urine of a poisoned person is described using gas chromatography mass spectrometry (GC-MS) with various ways of derivatization. It has been confirmed that one of its metabolic pathways leads to the corresponding 2-O-desmethyl and 5-O-desmethyl metabolites when the latter is prevailing. It is important to know the metabolism of this neurotoxic and hallucinogenic substance as it is a prerequisite for developing reliable toxicological diagnostic procedures and for assessment of toxicological risks.  相似文献   

12.
Ferreira MC 《Plastic and reconstructive surgery》2000,106(7):1630-5; discussion 1636-9
Aesthetic plastic surgery has received wide public attention in the past few years. Expectations of patients regarding results have been exaggerated; the real place and medical importance of the procedures are still not clear because of a lack of more objective evidence. This study discusses the difficulties encountered related to the scientific evaluation of the aesthetic operations and proposes alternatives for assessment. A frequently performed procedure, reduction mammaplasty, is presented as an example, with its specific evaluation.  相似文献   

13.
The assessment of the hazard associated with the introduction of chemical substances into the environment is receiving considerable attention in current ecological, political, and public forums. The purpose of this paper is to identify and evaluate the basic concepts involved in assessing the hazard of chemical substances to aquatic life. A conceptual framework for conducting a hazard assessment is elaborated. In addition, several proposed procedures for conducting aquatic hazard assessment are compared and contrasted. A discussion of the decision criteria currently utilized in hazard assessment procedures is included. The use of safety factors or uncertainty factors as a central concept in a sequential testing approach is presented. An assessment of the state-of-the-art in aquatic hazard assessment and recommendations for suceeding stpes in the development of procedures constitute the conclusion of the paper.  相似文献   

14.
The evidence regarding specific cardiac perception and discrimination, and its relationship to voluntary cardiac control, is critically reviewed. Studies are considered in three sections, depending on the method used to assess cardiac perception: questionnaire assessment, discrimination procedures, and heartbeat tracking. The heartbeat tracking procedure would appear to suffer least from interpretative difficulties. Recommendations are made regarding the style of analysis used to assess heartbeat perception in such tracking tasks.  相似文献   

15.
建立科学的绩效考核模式是医院提高员工积极性和创造性,提高医院运营效率和市场竞争力的重要手段。文章以医院绩效考核实践为基础,探讨如何建立以工作量核算为基础的绩效考核模式,包括绩效考核制定原则、核算体系、核算过程、分配形式、实践成效、工作体会等,为医院持续改进绩效考核工作提供参考。  相似文献   

16.
The evidence regarding specific cardiac perception and discrimination, and its relationship to voluntary cardiac control, is critically reviewed. Studies are considered in three sections, depending on the method used to assess cardiac perception: questionnaire assessment, discrimination procedures, and heartbeat tracking. The heartbeat tracking procedure would appear to suffer least from interpretative difficulties. Recommendations are made regarding the style of analysis used to assess heartbeat perception in such tracking tasks.  相似文献   

17.
18.
This article describes specific procedures for conducting quality assessment of Affymetrix GeneChip(R) soybean genome data and for performing analyses to determine differential gene expression using the open-source R programming environment in conjunction with the open-source Bioconductor software. We describe procedures for extracting those Affymetrix probe set IDs related specifically to the soybean genome on the Affymetrix soybean chip and demonstrate the use of exploratory plots including images of raw probe-level data, boxplots, density plots and M versus A plots. RNA degradation and recommended procedures from Affymetrix for quality control are discussed. An appropriate probe-level model provides an excellent quality assessment tool. To demonstrate this, we discuss and display chip pseudo-images of weights, residuals and signed residuals and additional probe-level modeling plots that may be used to identify aberrant chips. The Robust Multichip Averaging (RMA) procedure was used for background correction, normalization and summarization of the AffyBatch probe-level data to obtain expression level data and to discover differentially expressed genes. Examples of boxplots and MA plots are presented for the expression level data. Volcano plots and heatmaps are used to demonstrate the use of (log) fold changes in conjunction with ordinary and moderated t-statistics for determining interesting genes. We show, with real data, how implementation of functions in R and Bioconductor successfully identified differentially expressed genes that may play a role in soybean resistance to a fungal pathogen, Phakopsora pachyrhizi. Complete source code for performing all quality assessment and statistical procedures may be downloaded from our web source: http://css.ncifcrf.gov/services/download/MicroarraySoybean.zip.  相似文献   

19.
The implementation of sustainability in higher education has been advanced over at least the last two decades and brought sustainability assessment on the research agenda of Education for Sustainable Development (ESD) and sustainability science. Participatory approaches have gained increasing attention in these endeavours, but remain often vague and less addressed in sustainability assessment procedures. To fill in this gap, an indicator-based model, INDICARE, was developed that can assist in assessing participatory processes within higher education's sustainability initiatives. The objective of this paper is to introduce and discuss the model's theoretical background, its structure, applicability, and how it can broaden the perspectives on participation and sustainability assessment in the university context.Embedded in a cross-sectional qualitative research design, the model was developed in iterative stages and was presented and adjusted along six feedback loops, having been presented to 98 persons during conferences, workshops and university meetings. Inspired by biophilic ideas, transformative learning theories and participatory evaluation, INDICARE follows an ecocentric and integrative perspective that places the earth and its community at the centre of attention. A preliminary set of thirty indicators and practices, grouped in three categories of context, process, and transformation, is proposed. The assessment process itself is considered as a thought-provoking exercise rather than as a control tool and emphasizes the interplay of personal reflection and action-oriented outreach. INDICARE intends to invigorate the sustainability debate in higher education, in particular by proposing a more holistic approach to assessment that underlines experiencing the interconnectedness of human–nature relationships, combined with reflective exercises that can respond better to the call for transformation on individual and institutional level.  相似文献   

20.
Maintaining accurate laboratory measurements over time is crucial for assuring appropriate patient care and disease management. Accurate results over time and location are achieved by standardising measurements and establishing traceability to a reference system. Reference materials are key components of such reference systems and for establishing traceability. Commutability of reference materials is a critical property to ensure they are fit for use.Commutability is defined as the equivalence of the mathematical relationships between the results of different measurement procedures for a reference material and for representative samples from healthy and diseased individuals. This material characteristic is of special importance for measurement procedures that are optimised for measuring analytes directly in patient samples. The commutability of a reference material is measurement procedure specific and its assessment requires special experimental designs.This review explains the importance of commutability and summarises different experimental approaches described in the literature that have been used to assess the commutability of reference materials in clinical chemistry.  相似文献   

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