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1.
To collect information regarding Paya plant use practices, especially ethnomedical applications, an ethnobotanical study was conducted at the Santa Maria del Carbon community in north-central Honduras. Scientific and Paya names have been provided for 68 plants used for medicine, 40 used for food, 23 used as sources of wood, 8 used for beverages, 7 used in artifact manufacture and 10 used in other ways. Also, a list of 25 species is included for which the Paya have a name but no known use.  相似文献   

2.
An ethnobotanical study was conducted among the Jicaque Indians of the Montana de la Flor reservation in central Honduras to collect information regarding their plant-use practices. The data, including vernacular names, ecological settings, and uses, were recorded during collecting forays with Jicaque informants. Scientific and Jicaque names have been provided for 23 plant species used for food, 11 used for medicine, 4 used for beverages, 3 used as sources of wood, 5 in artifact manufacturing, and 3 used in other ways. Also, a list of 43 species is included for which the Jicaques have a name but no known use.  相似文献   

3.
Enucleation of a recipient oocyte is a crucially important process for nuclear transfer efficiency. Several procedures have been developed and used in the production of nuclear transfer embryos. Although the use of excitable fluorochromes and ultraviolet (UV) light are commonly used for complete enucleation, they also pose the risk of damaging the maternal cytoplast. Telophase and chemically assisted enucleation have also been used for cloning, but the quality and quantity of the recipient cytoplasm varies with the procedure used. This paper reviews various methods used for enucleation, and discusses their benefits and limitations with respect to cloning efficiency.  相似文献   

4.
Mutant analysis by polymerase chain reaction and restriction enzyme cleavage (MAPREC) has been developed for poliovirus to determine quantitatively for the presence of genomic changes in particular nucleotide sequences correlate with the characteristic of neurovirulence for monkeys. Currently the MAPREC is scheduled to be used as a routine safety test for oral poliomyelitis vaccine (OPV). Radioisotopes (RI) are used in MAPREC for quantitative determinations, a circumstance likely to limit its use. We investigated the possibility of developing a modified MAPREC, which did not require the use of radioisotopes, and developed a procedure designated NON-RI MAPREC. Conventional MAPREC and NON-RI MAPREC were then used in a series of studies in which analyses were performed on Sabin type 1 and Sabin type 3 attenuated vaccine polioviruses prepared under various conditions. Under the experimental conditions used, the stability of the genome of type 1 virus was shown to be markedly greater than that of the type 3 virus, and the frequency of mutants was observed to vary in relation to both the virus strain and the virus inoculum used. The results of the studies relating to the two analytical procedures used indicated that the reproducibility of both methods was of a similarly high order, but that MAPREC had a somewhat broader range of sensitivity than NON-RI MAPREC. As the quantity of genomic changes in OPV relating to neurovirulent properties are within the range of detection by NON-RI MAPREC, this procedure can be used as a quality control test for OPV.  相似文献   

5.
High-throughput screening of enzyme libraries   总被引:8,自引:0,他引:8  
Directed evolution is becoming a widely used technique for modifying or enhancing protein performance. Ultimately, the success of directed protein evolution experiments hinges on the efficiency of the methods used to screen libraries for mutants with properties of interest. Although there is still a paucity of general methods for enzyme library screening, in recent years a number of promising strategies have emerged and are increasingly being used to explore challenging issues in protein engineering.  相似文献   

6.
This paper presents a procedure for characterising the mechanical properties of skin using stochastic inverse identification. It is based on the minimisation of a cost function relative to the comparison between experimental suction experiments and their corresponding finite element models. Two different models are compared: a classical single-layer approach and a dual-layer medium which account for both the dermis and the hypodermis. Finite element results are used to construct the pre-optimisation database which is required for the inverse analysis. To compare the calculations, the entire identification is based on a dual-parameter optimisation procedure: for the single-layer approach a quadratic hyperelastic constitutive equation is used, whereas for the dual-layer medium a simple neo-Hookean potential is used. Theoretical conclusions, which are developed first, are then compared with actual case studies.  相似文献   

7.
To evaluate the activity of antiseptics and the sensitivity-resistance of bacteria to antiseptics, a number of characteristics has been used, including the minimum inhibiting concentration for different strains, the frequency of statistical and clinical resistance, the antiseptic activity index. A wide spread of S. aureus strains isolated from patients with hospital infections has been revealed. Differences in the resistance of bacterial strains have been established, depending on the type of the antiseptic and the ecovar of bacteria: among hospital ecovars, resistant strains occur more frequently and can resist a wider range of antibiotics. In staphylococcal hospital ecovars the occurrence and level of resistance to a number of widely used antiseptics increase with time. In connection with a wide spread of staphylococcal hospital strains resistant to antiseptics, measures on the control of the circulation of such strains should be introduced into hospitals, and the data thus obtained should be used for the periodic reevaluation of antiseptics used in medical practice and for the choice of preparations to be used for individual therapeutic and prophylactic antisepsis.  相似文献   

8.
1. Glucose oxidase (EC 1.1.3.4), amyloglucosidase (EC 3.2.1.3), invertase (EC 3.2.1.26) and beta-galactosidase (EC 3.2.1.23) were covalently attached via glutaraldehyde to the inside surface of nylon tube. 2. The linked enzyme system, comprising invertase immobilized within a nylon tube acting in series with glucose oxidase immobilized in a similar way, was used for the automated determination of sucrose. 3. The linked enzyme system, comprising beta-galactosidase immobilized within a nylon tube acting in series with glucose oxidase immobilized in a similar way, was used for the automated determination of lactose. 4. The linked enzyme system, comprising amyloglucosidase immobilized within a nylon tube acting in series with glucose oxidase immobilized in a similar way, was used for the automated determination of maltose. 5. Mixtures of glucose oxidase and amyloglucosidase were immobilized within the same piece of nylon tube and used for the automated determination of maltose. 6. Mixtures of glucose oxidase and invertase were immobilized within the same piece of nylon tube and used for the automated determination of sucrose.  相似文献   

9.
A consensus of expert opinion was used to provide both face and consensual validity to a list of potential indicators of sheep welfare. This approach was used as a first step in the identification of valid welfare indicators for sheep. The consensus methodology of the National Institute of Health, using pre-meeting consultation and focus group discussions, was used to ascertain the consensus opinion of a panel of sheep welfare experts. The Farm Animal Welfare Council's five freedoms were used as a framework to organise a list of current on-farm welfare issues for sheep. The five freedoms were also the welfare criterion used to identify potential on-farm welfare indicators for sheep. As a result, experts identified 193 welfare issues for sheep and lambs managed on farms across England and Wales. Subsequently, a combination of animal- (n = 26), resource- (n = 13) and management- (n = 22) based indicators was suggested for (i) adult rams, (ii) adult ewes (male and female sheep, over 1 year old), (iii) growing lambs (male and female sheep, over 6 weeks to 1 year old) and (iv) young lambs (male and female lambs, 6 weeks old and under). The results from this study could therefore be used to inform the further development of valid methods of assessing the on-farm welfare of sheep.  相似文献   

10.
Fundamentals of flow cytometry   总被引:4,自引:0,他引:4  
Flow cytomelers arc instruments that arc used primarily to measure the physical and biochemical characteristics of biological particles. This technology is used to perform measurements on whole cells as well as prepared cellular constituents, such as nuclei and organelles. Flow cytomcters are investigative tools for a broad range of scientific disciplines because they make measurements on thousands of individual cells/ particles in a matter of seconds. This is a unique advantage relative to other detection instruments that provide bulk particle measurements. Flow cytomety is a complex and highly technical field; therefore, a basic understanding of the technology is essential for all users. The purpose of this article is to provide fundamental information about the instrumentation used for flow cytometry as well as the methods used to analyze and interpret data. This information will provide a foundation to use flow cytometry effectively as a research tool.  相似文献   

11.
R. F. Irvine 《CMAJ》1964,90(24):1369-1371
Underexposed or underdeveloped radiographs which could have been used for teaching or publication were treated prior to photographing with a technique similar to that used for photographic negative retouching. This method enables these radiographs to be used for diagnostic demonstration, where before they would have been condemned as unsuitable for reproduction. The method is simple and requires very little experience or equipment.  相似文献   

12.
Cometabolic degradation of trichloroethylene in a bubble column bioscrubber   总被引:1,自引:0,他引:1  
A bubble column bioreactor was used as bioscrubber to carry out a feasibility study for the cometabolic degradation of trichloroethylene (TCE). Phenol was used as cosubstrate and inducer. The bioreactor was operated like a conventional chemostat with regard to the cosubstrate and low dilution rates were used to minimize the liquid outflow. TCE degradation measurements were carried out using superficial gas velocities between 0.47and 4.07 cm s(-1) and TCE gas phase loads between 0.07 and 0.40 mg L(-1) Depending on the superficial gas velocity used, degrees of conversion between 30% and 80% were obtained. A simplified reactor model using plug flow for the gas phase, mixed flow for the liquid phase, and pseudo first order reaction kinetics for the conversionof TCE was established. The model is able to give a reasonable approximation of the experimental data. TCE degradation at the used experimental conditions is mainly limited by reaction rate rather than by mass transfer rate. The model can be used to calculate the reactor volume and the biomass concentration for a required conversion. (c) 1995 John Wiley & Sons Inc.  相似文献   

13.
Linear regression equations are commonly used in conjunction with experimental data to provide linear relationships between quantities which are dimensionally distinct. In many cases theoretical relationships between such quantities are known and can be used as a basis for non-linear regression equations. This study compares linear and non-linear approaches for estimating the segmental moments of inertia from anthropometric measurements using the data of Chandler et al. [Chandler et al. (1975) Investigation of inertial properties of the human body. AMRL Technical Report 74-137, Wright Patterson Air Force Base. OH.] Right limb data were used to derive the equations while left limb data were used as a cross-validation sample to evaluate the inertia estimates calculated from the equations. For the limb segments the standard error estimates had average values of 21% for the linear equations and 13% for the non-linear equations. Data on a 10 yr-old boy was used to compare the two approaches outside the sample range. The mean percentage residuals were 286% for the linear equations and 20% for the non-linear equations. A set of non-linear equations is provided.  相似文献   

14.
Biting and chewing by horses on crossties can result in injury to the handler and damage to equipment. Operant-conditioning techniques have been used to train horses and could be used to reduce or eliminate undesirable biting and chewing. Presently, a differential-reinforcement-of-other-behavior (DRO) schedule, in the context of a reversal design, was effective in reducing biting and chewing in two horses. In DRO schedules, a reinforcer is delivered contingent on the absence of a target behavior for a specified interval. Positive-reinforcement procedures offer an alternative to aversive-control techniques typically used in equine training and may provide for better equine welfare and horse-human interaction.  相似文献   

15.
Lymphedema of the eyelids is a relatively rare condition whose main effect is to obstruct vision, and it is unsightly. We present 3 cases in which the edema was treated by excision and skin grafting of the eyelid, with satisfactory functional and cosmetic results. It is suggested that a split-skin graft be used for the upper eyelid and a full-thickenss graft for the lower eyelid. The lower eyelid skin can be "de-fatted" and used as a graft, but in the more severe cases we suggest a postauricular skin graft be used.  相似文献   

16.
- Preamble. In this series of two papers, a methodology to calculate the average number of times a material is used in a society from cradle to grave is presented and applied to allocation of environmental impact of virgin material. Part 1 focuses on methodology development and shows how the methodology works with hypothetical examples of material flows. Part 2 presents case studies for steel recycling in Japan, in which the methodology is applied and allocation of environmental impact of virgin steel is conducted. - Abstract Goal, Scope and Background. It has been recognized that LCA has a limitation in assessing open cycle recycling of materials because of inevitable subjective judgments in setting system boundary. According with the enforcement of recycling laws, there has been a rapid increase in recycling ratio of materials at the end-of-life of products in many industrialized countries. So, materials' life cycle is getting more complicated, which makes it difficult to quantify the environmental impacts of materials used in a product in an appropriate way. The purpose of this paper is to develop a methodology to calculate the average number of times a material is used in a society from cradle to grave. The method developed in this paper derives the average number of times material is used; this value could be used for allocation of environmental burdens of virgin material as well as an indicator for assessing the state of material use in a certain year, based on material flow of material in that year. Main Features Our methodology is based on Markov chain model using matrix-based numerical analysis. A major feature of this method is that it creates transition probability matrices for a material from the way in which the material is produced, consumed, and recycled, making it possible to simply elicit indicators that assess the status of material use in products in society. Our methodology could be an alternative method to derive the average number of times material is used, which could be used for allocation of environmental burdens of virgin material. Results and Discussions The methodology was applied to hypothetical examples of material flows, in which a virgin material was produced and used in products, recycled and finally landfilled. In some cases, closed loop and open loop recycling of materials existed. The transition probability matrix was created for each material flow, and how many times a virgin material is used in products until all of the elements are ultimately landfilled. Conclusions This methodology is applicable to a complicated material flow if the status of residence of a material and its flow in a society can be figured out. All the necessary data are the amount of virgin material production, amount of the material used in products, recycling rate of the material at the end of life of each product, the amount of scrap of the material that are used for products. In Part 2 of this paper, case studies for steel were conducted.  相似文献   

17.
1,3-propanediol (1,3-PD) is a chemical compound of immense importance primarily used as a raw material for fiber and textile industry. It can be produced by the fermentation of glycerol available abundantly as a by-product from the biodiesel plant. The present study was aimed at determination of key kinetic parameters of 1,3-PD fermentation by Clostridium diolis. Initial experiments on microbial growth inhibition were followed by optimization of nutrient medium recipe by statistical means. Batch kinetic data from studies in bioreactor using optimum concentration of variables obtained from statistical medium design was used for estimation of kinetic parameters of 1,3-PD production. Direct use of raw glycerol from biodiesel plant without any pre-treatment for 1,3-PD production using this strain investigated for the first time in this work gave results comparable to commercial glycerol. The parameter values obtained in this study would be used to develop a mathematical model for 1,3-PD to be used as a guide for designing various reactor operating strategies for further improving 1,3-PD production. An outline of protocol for model development has been discussed in the present work.  相似文献   

18.
Statistical and genetic programming techniques have been used to predict the software development effort of large software projects. In this paper, a genetic programming model was used for predicting the effort required in individually developed projects. Accuracy obtained from a genetic programming model was compared against one generated from the application of a statistical regression model. A sample of 219 projects developed by 71 practitioners was used for generating the two models, whereas another sample of 130 projects developed by 38 practitioners was used for validating them. The models used two kinds of lines of code as well as programming language experience as independent variables. Accuracy results from the model obtained with genetic programming suggest that it could be used to predict the software development effort of individual projects when these projects have been developed in a disciplined manner within a development-controlled environment.  相似文献   

19.
Enzymatic synthesis of novel glutathione analogs   总被引:2,自引:0,他引:2  
A strain of Escherichia coli enriched in its content of gamma-glutamylcysteine synthetase and glutathione synthetase by recombinant DNA techniques has been immobilized in a carrageenan matrix and used for the synthesis of various types of isotopically labeled glutathione (L-gamma-glutamyl-L-cysteinyl-glycine) (K. Murata, W. A. Abbott, R. J. Bridges, and A. Meister (1985) Anal. Biochem. 150, 235-237). In the present work, this E. coli matrix was used as the basis of a method for the synthesis of glutathione analogs. Thus, amino acid analogs were used in place of the corresponding amino acid constituents of glutathione (e.g., 4-fluoroglutamate was substituted for glutamate) in the reaction mixtures. Using this method we have synthesized several analogs of glutathione including L-gamma-glutamyl-(beta-chloro)-L-alanyl-glycine, (R,S)-4-fluoro-DL-gamma-glutamyl-L-cysteinyl-glycine, D-gamma-glutamyl-L-cysteinyl-glycine, and L-gamma-glutamyl-L-homocysteinyl-glycine. This method may also be used for the synthesis of a number of L- and D-gamma-glutamyl amino acids. The analogs are purified by gel-filtration and ion-exchange chromatography. The analogs are used to examine the substrate specificity and mechanisms of action of glutathione-utilizing enzymes and for studies on glutathione metabolism and function. Fluorine-containing analogs may be used for NMR studies. The enzymatically prepared compounds may also be used as intermediates in the chemical synthesis of other analogs of glutathione and glutathione disulfide.  相似文献   

20.
AIMS: Development of a simple, specific, rapid and inexpensive Dot-ELISA test for diagnosis of rotaviral antigen in stool samples. METHODS AND RESULTS: Hyperimmune rabbit antisera raised against SA-11 (Simian Agent-11) strain was used as primary antibody. The secondary antibody conjugate used was the goat anti-rabbit IgG alkaline phosphatase, and BCIP/NBT solution was used as substrate. Faecal extracts were diluted 10-fold and used for the detection of rotavirus antigen. RNA-PAGE was performed to compare the specificity and sensitivity of the diagnostic tests. Dot-ELISA positive samples were further confirmed by Western blot analysis. CONCLUSIONS: This Dot-ELISA test could be used as an alternative method for diagnosing rotaviral samples in the field. SIGNIFICANCE AND IMPACT OF THE STUDY: The Dot-ELISA test is simple, specific, rapid and cost effective. It is suitable for identifying a large number of samples obtained from epidemiological studies and hence, reducing the death rate of rotavirus-infected patients.  相似文献   

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