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1.
Slope failure and soil erosion due to increased development activity in hilly areas can be catastrophic and affect the environment and humans’ well-being. This article investigates the parameters that contribute to environmental risk. Nine contributing parameters were identified. Rating the risk was proposed based on the prediction of occurrences of environmental issues and were categorized from very high (5) to very low (1) with high, medium, and low in between. The assessments were reviewed and evaluated based on rating for the chosen parameters. Maps quantifying risks were developed identifying areas of environmental risk. The overall result shows that development areas PD3 of Tanjung Bungah, and PD3, PD8, and PD9 of Paya Terubong have high rating of environmental risk. No development area is classified as very high risk or very low risk. The rating can be used to develop zones of potential high risk, and from this zoning guideline the viability can be measured for any proposed development.  相似文献   

2.
Histamine is an important mediator of immediate hypersensitivity for both animals and humans. The action of histamine on target tissues is believed to be mediated by specific cell surface receptors, especially H1 and H2 receptors for hypersensitivity and inflammatory reactions, which involve stimulation of smooth muscle contractility, alterations in vascular permeability, and modifications in the activities of macrophages and lymphocytes. Although the nature of histamine receptors in the brain and peripheral tissues has been studied extensively by many laboratories, the molecular mechanism of histamine receptor-mediated reactions is not fully understood, mainly because histamine receptors are incompletely characterized from the biochemical point of view. In previous studies, we have found that the cultured smooth muscle cell line DDT1MF-2, derived from hamster vas deferens, expresses low-affinity histamine H1 receptors and responds biochemically and functionally to H1-specific stimulation (Mitsuhashi and Payan, J Cell Physiol 134:367, 1988). This cell line provides a model for analyzing the biochemical responses of H1 receptor-mediated reactions in peripheral tissues. In this review, we summarized our recent progress in the study of low-affinity H1 receptors on DDT1MF-2 cells.  相似文献   

3.
ABSTRACT: BACKGROUND: Sabang Municipality, in Aceh Province, Indonesia, plans to initiate a malaria elimination programme in 2013. A baseline survey of the distribution of malaria in the municipality was conducted to lay the foundations for an evidence-based programme and to assess the island's readiness to begin the elimination process. METHODS: The entire population of the municipality was screened for malaria infection and G6PD deficiency. Specimens collected included blood slides, blots and tubes for selected households. Results and Discussion Samples were collected from 16,229 residents. Microscopic examination of the blood smears revealed 12 malaria infections; 10 with Plasmodium falciparum and 2 with Plasmodium vivax. To confirm the parasite prevalence, polymerase chain reaction (PCR) diagnosis was performed on the entire positive cases by microscopy and randomized 10% of the microscopically negative blood samples. PCR revealed an additional 11 subjects with malaria; one P. falciparum infection from the village of Paya Keunekai, and nine P. vivax infections and one mixed P. falciparum/P. vivax infection from the village of Batee Shok. The overall slide positivity rate was 0.074% (CI 95%: 0.070 - 0.078) and PCR corrected prevalence 0,590% (CI 95%: 0.582 - 0.597). Analysis of 937 blood samples for G6PD deficiency revealed two subjects (0.2%) of deficient G6PD. Analysis of several genes of the parasite, such as Pfdhfr, Pfdhps, Pfmdr1, Pfcrt, Pfmsp1, Pfmsp2, Pvdhfr, Pvdhps, Pvmdr1 and host gene, such as G6PD gene revealed that both P. falciparum and P. vivax carried the mutation associated with chloroquine resistance. CONCLUSION: Malariometric and host genetic analysis indicated that there is a low prevalence of both malaria and G6PD deficiency in the population of Sabang Municipality. Nevertheless, malaria cases were clustered in three rural villages and efforts for malaria elimination in Sabang should be particularly focused on those three villages.  相似文献   

4.
Chemical biodiversity of essential oils of natural populations of Aloysia citrodora Palau (“lemon verbena”, “cedrón”) in Northwestern Argentina was assessed by collecting in the same sites through different years. A total of 36 samples were collected in the Provinces of Salta (El Maray, La Paya, El Sunchal, El Alisal, Chorrillos), Jujuy (Chilcayo, San Roque), Catamarca (Mutquin, Colana) and Tucumán (Amaicha del Valle) in Argentina.Essential oils were obtained by hydrodistillation (Clevenger) of naturally air-dried plant material. Yields ranged from 0.16% to 1.93% (v/w), being the highest those of the collections of Mutquin. More than 65 compounds were identified by CG-FID-MS. Only 19 of these constituents, accounting from 77.3 to 98.9% of the total oil, present in more than 4.0% in at least one sample, were considered as variables for statistical analysis. Agglomerative Hierarchical Cluster analysis was conducted, showing at 65% of similarity, five groups. This grouping was in direct accordance to the biosynthetic pathways of main compounds (chemotypes).In the two sites of Jujuy, 21 collections evidenced four different chemotypes, named after the dominant component as follows: thujones, citronellal, carvone, and citral (neral + geranial). In the populations of Salta and Catamarca, linalool appeared as a new different chemotype.Though cedron is considered as a citral-bearing plant, curiously, in the 36 samples collected in the NW of Argentina, only two samples contained citral as main constituent. On the other hand, a dominance of citronellal and thujones compositions were found in the bulk of the samples collected, while others had very high content of linalool or carvone and its derivatives. Northwestern Argentina has repeatedly been mentioned as the center of biodiversity of this species.The new evidences found on the chemical biodiversity of essential oils of Aloysia citrodora in natural populations in this region, reinforce firmly this idea.  相似文献   

5.
Monoclonal antibodies (MoAbs) have had a major impact on many areas of biomedical research and almost since their advent have been used in the characterisation and identification of diagnostically important antigens of fungal pathogens. Their main significance lies in three, often inter-related areas: a) the definition and characterisation of antigens for use in detection of antibody responses, b) their direct use in the detection of diagnostically useful antigen in body fluids c) their application in immunohistochemical diagnosis. The degree to which MoAbs have been applied varies between fungal pathogens, and they have now been used, for example, in the serodiagnosis of Aspergillus spp., Cryptococcus neoformans, Histoplasma capsulatum and Paracoccidioides brasiliensis. Their use in producing diagnostic tests for other fungi such as Sporothrix schenckii and Penicillium marneffei has been more restricted but considerable potential exists for further development.  相似文献   

6.
We have developed a laser-aligned measuring device to facilitate the measurement of linear hand dimensions. Our objective has been to make a simple, clinically applicable device for anthropometry of the hands in patients with arthritis in order to gauge the progression of hand deformities. The system provides an alternative to the use of rules, tapes, photogrammetry and least-squares devices which have previously been applied to hand measurements. The system delivers results which are not significantly different from those measured with rules and callipers and has a similar level of accuracy. The use of laser pointers for alignment facilitates measurements which necessitate picking the highest point of the hand. The device is portable and simple to use in the clinic. We have used it to measure hand dimensions in normal subjects and patients with arthritis. However, the system could equally well be used to facilitate measurement of other objects with an irregular surface profile.  相似文献   

7.
The yeast Saccharomyces cerevisiae has been widely used for the implementation of DNA chip technologies. For this reason and due to the extensive use of this organism for basic and applied studies, yeast DNA chips are being used by many laboratories for expression or genomic analyses. While membrane arrays (macroarrays) offer several advantages, for many laboratories they are not affordable. Here we report that a cluster of four Spanish molecular-biology yeast laboratories, with relatively small budgets, have developed a complete set of probes for the genome of S. cerevisiae. These have been used to produce a new type of macroarray on a nylon surface. The macroarrays have been evaluated and protocols for their use have been optimized.  相似文献   

8.
Conventional assays for quantifying the virulence of microbial pathogens and mutants have traditionally relied upon the use of a range of mammalian species. A number of workers have demonstrated that insects can be used for evaluating microbial pathogenicity and provide results comparable to those that can be obtained with mammals since one component of the vertebrate immune system, the innate immune response, remains similar to that found in insects. Larvae of the Greater Wax Moth Galleria mellonella have been used to evaluate the virulence of a range of bacterial and fungal pathogens and a correlation with the virulence of these microbes in mice has been established. This review highlights the similarities of the vertebrate and insect innate immune responses to infection and identifies the potential use of insects for the in vivo evaluation of the microbial pathogenicity.  相似文献   

9.
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   

10.
Monoclonal antibodies (MAbs) for fish viruses have been used increasingly in fish health management programs and as tools in research. The initial and most widespread use has been in the development of improved diagnostic and virus identification assays. MAbs with broad reactivity that provide standardized reagents for use in general screening assays for particular groups of fish viruses have been developed, whereas MAbs with more restricted specificities permit the rapid serotyping of fish viruses and, in some cases, the identification of specific virus strains. The large number and variety of MAbs now available for some fish viruses, such as the aquatic birnaviruses and rhabdoviruses, present an ideal opportunity to select appropriate MAbs to construct standardized virus identification assays for use by all fish pathologists worldwide. Furthermore, these MAbs have been used to identify specific epitopes that stimulate a protective immune response to many fish viruses, and to investigate the mechanisms of antibody-mediated neutralization of fish viruses. They also have been used to study the epidemiology of specific viruses as well as antigenic variation and the mechanisms by which new strains arise. Such information is important for the development of reliable diagnostic assays for short-term control methods as well as the development of effective vaccines for long-term control of virus diseases in fish. This article presents a brief overview of MAb production and a review of some current applications of MAbs in the identification and characterization of viruses of fish.  相似文献   

11.
Few studies have focused on the significance of ras protein levels in human malignancy, in part because of the inherent difficulty in quantitation of the ras gene product. We have developed a method for the enzymatic determination of the ras gene product and have used this method for the quantitation of ras gene product levels in 19 patients with acute leukemia. This technique provides a practical means to assess p21 expression in leukemic cells ex vivo while avoiding the use of radioactive reagents. In addition, the mobility of the ras species of interest is determined. This assay should be easily modified for the use of other antibodies such as those reported to be specific for various ras species (i.e., H-, K- and N-ras), for specific ras mutations or for other nonras proteins. Because of the use of electrophoresis prior to quantitation of protein, the antibody used does not need to possess high specificity for the protein of interest.  相似文献   

12.
Impact of land use changes on mountain vegetation   总被引:1,自引:0,他引:1  
Abstract. In this study the impact of land use changes on vegetation in the sub‐alpine‐alpine belt is analysed. The study sites (4.7 km2) are located in the Passeier Valley (South Tyrol, Italy), at an elevation of 1500–2300 m a.s.l. The whole study area was used for hay‐making ca. 60 yr ago. Today, part of the meadows are more intensively used, while other parts have been converted to pasture or have been abandoned. We analysed the reasons for these land use changes and the effects on vegetation with a Geographical Information System and geostatistical analysis. The result of these analyses are: (1) Current land use is mainly controlled by the degree of accessibility for vehicles. Accessible areas are being used more and more intensively, while poorly accessible areas are being abandoned or used as pasture. (2) Current vegetation is highly determined by current land use. Particular vegetation units can be assigned to each form of land use. (3) Succession starts immediately after abandonment. Depending on altitude, succession proceeds at different speeds and with different numbers of stages. Hence the type of vegetation indicates the time passed since abandonment. (4) Land use changes lead to characteristic changes in vegetation; they are considered to be the most important driving force for vegetation change. (5) Measures of intensification and abandonment of extensively used areas both lead to a decrease in the number of species.  相似文献   

13.
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   

14.
Endovascular stents have revolutionised the field of interventional cardiology. Despite their excellent clinical outcome complications associated with percutaneous stent implantation following the procedure have remained a major drawback in their widespread use. To overcome such limitations, a number of novel endovascular stents have emerged including a covered stent wrapped in a thin membrane sleeve. As well as prevention of complications associated with stenting, covered stents owing to their physical barrier are used as the treatment option of choice for trauma devices during emergency situations and to treat a number of pathological disease states. The aim of this review is to provide the reader with an overall objective outlook in the use of covered stents as a treatment option in a number of vascular complications and addresses their design and materials used in the manufacturing process. In addition, new strategies are highlighted and future prospects with the emergence of novel smart alloys for 3D scaffolds and the use of nanotechnology in the development of nanocomposite materials.  相似文献   

15.
Microbubbles have been used in a variety of fields and have unique properties, for example shrinking collapse, long lifetime, efficient gas solubility, a negatively charged surface, and the ability to produce free radicals. In medicine, microbubbles have been used mainly as diagnostic aids to scan various organs of the body, and they have recently been investigated for use in drug and gene delivery. However, there have been no reports of blood oxygenation by use of oxygen microbubble fluids without shell reagents. In this study, we demonstrated that nano or microbubbles can achieve oxygen supersaturation of fluids, and may be sufficiently small and safe for infusion into blood vessels. Although Po(2) increases in fluids resulting from use of microbubbles were inhibited by polar solvents, normal saline solution (NSS) was little affected. Thus, NSS is suitable for production of oxygen-rich fluid. In addition, oxygen microbubble NSS effectively improved hypoxic conditions in blood. Thus, use of oxygen microbubble (nanobubble) fluids is a potentially effective novel method for oxygenation of hypoxic tissues, for infection control, and for anticancer treatment.  相似文献   

16.
Feucht A  Lewis PJ 《Gene》2001,264(2):289-297
The intrinsically fluorescent green fluorescent protein has been used in many laboratories as a cytological marker to monitor protein localisation in live cells. Multiple spectrally modified mutant versions and novel fluorescent proteins from other species have subsequently been reported and used for labelling cells with multiple fluorescent protein fusions. In this work we report the design and use of vectors containing some of these spectral variants of GFP for use in the Gram positive bacterium Bacillus subtilis. These vectors complement those previously described (Lewis and Marston, 1999. Gene 227, 101-109) to provide a large suite of plasmid vectors for use in this and other related Gram positive organisms. Using these vectors we have been able to directly demonstrate the sequential assembly/disassembly of proteins involved in the generation of cellular asymmetry during development.  相似文献   

17.
A Wright  K Maundrell  W D Heyer  D Beach  P Nurse 《Plasmid》1986,15(2):156-158
We have constructed a variety of vectors for use in both budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe). Four of these, pDB262, pWH4, pWH5, and pMAK262, have positive selection for the insertion of cloned DNA, making them convenient for the construction of gene banks. pDB262, pWH4 and pWH5 contain the 2 mu ARS and the LEU2 gene from S. cerevisiae and can be used for gene isolation. They can also be converted into integration vectors for use in the genetic mapping of cloned sequences. pMAK262 contains only the LEU2 gene from budding yeast and can be used to screen for ARS elements or for gene integration. We also describe two other integration vectors, pDAM3 and pDAM6, which have a variety of restriction sites suitable for subcloning.  相似文献   

18.
Satellite telemetry using ARGOS platform transmitter terminals (PTTs) is widely used to track the movements of animals, but little is known of the accuracy of these systems when used on active terrestrial mammals. An accurate estimate of the error, and therefore the limitations of the data, is critical when assessing the level of confidence in results. ARGOS provides published 68th percentile error estimates for the three most accurate location classes (LCs), but studies have shown that the errors can be far greater when the devices are attached to free‐living animals. Here we use data from a study looking at the habitat use of the spectacled flying‐fox in the wet tropics of Queensland to calculate these errors for all LCs in free‐living terrestrial mammals, and use these results to assess what level of confidence we would have in habitat use assignment in the study area. The results showed that our calculated 68th percentile errors were larger than the published ARGOS errors for all LCs, and that for all classes the error frequency had a very long tail. Habitat use results showed that the size of the error compared with the scale of the habitat the study was conducted in makes it unlikely that our data can be used to assess habitat use with great confidence. Overall, our results show that while satellite telemetry results are useful for assessing large scale movements of animals, in complex landscapes they may not be accurate enough to be used for finer scale analysis including habitat use assessment.  相似文献   

19.
Occupational radiation doses from interventional procedures have the potential to be relatively high. The requirement to optimise these doses encourages the use of electronic or active personal dosimeters (APDs) which are now increasingly used in hospitals. They are typically used in tandem with a routine passive dosimetry monitoring programme, with APDs used for real-time readings, for training purposes and when new imaging technology is introduced. However, there are limitations when using APDs. A survey in hospitals to identify issues related to the use of APDs was recently completed, along with an extensive series of APD tests by the EURADOS Working Group 12 on Dosimetry for Medical Imaging. The aim of this review paper is to summarise the state of the art regarding the use of APDs. We also used the results of our survey and our tests to develop a set of recommendations for the use of APDs in the clinical interventional radiology/cardiology settings, and draw attention to some of the current challenges.  相似文献   

20.
Objective To determine whether failure to adequately adjust for a reported 40% misclassification of use of in vitro fertilisation (IVF) as reported in a Swedish study could have led to a false finding that folic acid increases dizygotic twinning.Design Modelling with population based data.Setting Swedish vital records for 1995-9.Main outcome measures Rates of twinning calculated according to whether women used IVF to become pregnant. Estimated unadjusted and adjusted odds ratios of the association between use of folic acid and twinning by use of IVF.Results In 1995-9, Swedish women who used IVF had an almost 20 times the chance of having twins than women who did not use IVF (rate ratio 19.7, 95% confidence interval 18.7 to 20.6). In the absence of a true effect of folic acid, the use of a 40% misclassified surrogate variable to adjust for use of IVF would have resulted in a false finding that folic acid was associated with a more than twofold increase in twinning.Conclusion Use of IVF is a strong confounder because it is associated with both use of folic acid and twinning. Even when misclassification of IVF was reduced to 5%, this bias persisted in the adjusted model. Using a 40% misclassified surrogate to adjust for IVF, as reported in the Swedish study, probably led to a false finding that folic acid increased dizygotic twinning.  相似文献   

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