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1.
Background
Accurate parasitological diagnosis of malaria is essential for targeting treatment where more than one species coexist. In this study, three rapid diagnostic tests (RDTs) (AccessBio CareStart (CSPfPan), CareStart PfPv (CSPfPv) and Standard Diagnostics Bioline (SDBPfPv)) were evaluated for their ability to detect natural Plasmodium vivax infections in a basic clinic setting. The potential for locally made evaporative cooling boxes (ECB) to protect the tests from heat damage in high summer temperatures was also investigated.Methods
Venous blood was drawn from P. vivax positive patients in Jalalabad, Afghanistan and tested against a panel of six RDTs. The panel comprised two of each test type; one group was stored at room temperature and the other in an ECB. RDT results were evaluated against a consensus gold standard based on two double-read reference slides and PCR. The sensitivity, specificity and a measure of global performance for each test were determined and stratified by parasitaemia level and storage condition.Results
In total, 306 patients were recruited, of which 284 were positive for P. vivax, one for Plasmodium malariae and none for Plasmodium falciparum; 21 were negative. All three RDTs were specific for malaria. The sensitivity and global performance index for each test were as follows: CSPfPan [98.6%, 95.1%], CSPfPv [91.9%, 90.5%] and SDBPfPv [96.5%, 82.9%], respectively. CSPfPv was 16% less sensitive to a parasitaemia below 5,000/μL. Room temperature storage of SDBPfPv led to a high proportion of invalid results (17%), which reduced to 10% in the ECB. Throughout the testing period, the ECB maintained ~8°C reduction over ambient temperatures and never exceeded 30°C.Conclusions
Of the three RDTs, the CSPfPan test was the most consistent and reliable, rendering it appropriate for this P. vivax predominant region. The CSPfPv test proved unsuitable owing to its reduced sensitivity at a parasitaemia below 5,000/μL (affecting 43% of study samples). Although the SDBPfPv device was more sensitive than the CSPfPv test, its invalid rate was unacceptably high. ECB storage reduced the proportion of invalid results for the SDBPfPv test, but surprisingly had no impact on RDT sensitivity at low parasitaemia. 相似文献2.
Plant-based repellents have been used for generations in traditional practice as a personal protection measure against host-seeking mosquitoes. Knowledge on traditional repellent plants obtained through ethnobotanical studies is a valuable resource for the development of new natural products. Recently, commercial repellent products containing plant-based ingredients have gained increasing popularity among consumers, as these are commonly perceived as "safe" in comparison to long-established synthetic repellents although this is sometimes a misconception. To date insufficient studies have followed standard WHO Pesticide Evaluation Scheme guidelines for repellent testing. There is a need for further standardized studies in order to better evaluate repellent compounds and develop new products that offer high repellency as well as good consumer safety. This paper presents a summary of recent information on testing, efficacy and safety of plant-based repellents as well as promising new developments in the field. 相似文献
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Gregory M. Wagner 《The Botanical review》1997,63(1):1-26
TheAzolla-Anabaena symbiosis is outstanding due to its high productivity combined with its ability to fix nitrogen at high rates. Because of this, in recent decades, countless studies have been conducted on this association, but with insufficient synthesis and coordination. This paper, therefore, attempts to review and synthesize past and recent findings concerning the biology and utilization ofAzolla in hopes that this will facilitate increased future collaborative research on this “green gold mine.” It reviews the taxonomy, distribution, morphology, physiology, and reproduction ofAzolla as well as new developments in its manifold uses. Because of the growing concern about conservation of the environment and the need for deploying renewable, sustainable resources; the application ofAzolla as a biofertilizer on agricultural crops, in order to provide a natural source of the crucial nutrient nitrogen, can be very beneficial to the future of our planet. Besides the environmental appropriateness of the use ofAzolla, for multitudes of farmers in many parts of the world who cannot afford chemical fertilizers,Azolla application can enhance their economic status, increasing yields while minimizing costs. Due to the fact that rice paddy fields form an ideal environment forAzolla, one of its most suitable applications is on rice. Besides its utilization as a biofertilizer on a variety of crops,Azolla can be used as an animal feed, a human food, a medicine, and a water purifier. It may also be used for the production of hydrogen fuel, the production of biogas, the control of weeds, the control of mosquitoes, and the reduction of ammonia volatilization which accompanies the application of chemical nitrogen fertilizer. 相似文献
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A commercially available assay for aldosterone that requires no extraction was found to be valid without modification for rat serum. The assay was performed in duplicate on as little as 0.5 cc of rat serum and gave linear results from 5 ng/dl to 500 ng/dl, (i.e., the physiological range of the rat). Samples above 150 ng/dl had to be diluted in this assay. The cost per sample if performed in duplicate and in batches was approximately one dollar. We found that this assay, which was developed for and is marketed for determining aldosterone concentration in human samples, offered a cost effective assay for aldosterone determination in the rat. 相似文献
5.
Hugh S. Mason 《In vitro cellular & developmental biology. Plant》2002,38(3):237-240
Summary The use of plants for production and delivery of vaccine proteins has shown promise in research conduced during the past decade.
Genes encoding bacterial and viral antigens are faithfully expressed, processed, and assembled in plant cells to form immunogenic
proteins. Studies in animals and humans showed that ingestion of transgenic potato containing vaccine proteins caused production
of antigen-specific antibodies in serum and mucosal secretions. Future studies must aim to improve antigen expression and
to develop processes to formulate plant material for antigen stability and convenient oral delivery. Furthermore, production
methods should ensure the containment of pharmaceutical crops and prevent contamination of the food supply. 相似文献
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Estimating plant biomass: A review of techniques 总被引:1,自引:0,他引:1
Abstract Many different techniques have been used to estimate biomass for ecological, agricultural and forestry research. The most suitable technique depends on available budget, accuracy required, structure and composition of the vegetation, and whether species and component biomass are required. A survey of the methods that have been used to estimate biomass is given, and the advantages and disadvantages of direct sampling, calibrated visual estimation and double sampling techniques are discussed. The relative cost and accuracy of each technique are summarized and recommendations are made for the use of the techniques in different vegetation complexes, such as discrete shrubs or trees, patchy vegetation, homogeneous vegetation, and species-rich inhomogeneous heathland. 相似文献
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Lepor H 《Reviews in urology》2005,7(Z2):S11-S17
Since the early 20th century, radical prostatectomy has been used in the treatment of prostate cancer. However, before the widespread acceptance of prostate-specific antigen screening, the majority of cancers were clinically advanced and not amenable to cure, so relatively few men were candidates for this procedure. Modern advances have contributed dramatically to the reduction of complications and morbidity associated with radical prostatectomy. As a result, the procedure has become the most common treatment selected by men with localized prostate cancer. This article reviews several issues regarding radical prostatectomy, including surgical techniques, cancer control, intraoperative localization of the cavernous nerves, patient selection, and laparoscopic versus robotic approaches. 相似文献
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The impact of domestic and wild Caprini browsing on Quercus ilex has been examined in an area of the Sierra de Cazorla. Vegetation as a herbivore food supply, herbivore feeding regime and density in the study area during six sampling periods throughout two years, has been quantified. Wild Caprini show diets similar to the available vegetation, whereas domestic Caprini tend more towards the trophic specialities (browsing or grazing) of their genus. Nevertheless, this tendency was more pronounced in domestic goats than in sheep. A hypothetical estimate of Q. ilex intake by each species under the study conditions was carried out. It was found that domestic Caprini have a greater impact on the holm oak than wild Caprini, density and feeding-niche deviations being the main factors responsible for this situation.Abbreviations DM=
dry matter 相似文献
12.
A dialysis pretreatment to remove low molecular weight interfering compounds from potato protein water prior to measuring its lysine availability is described. After dialysis the ?-trinitrophenyl-l-lysine showed excellent correlation with the magnitude of heat treatment the protein water received. Conversely, analysis of the same sample without pretreatment yielded erratic results. 相似文献
13.
ObjectiveTo review the effectiveness of computer support for determining optimum drug dose.DesignSystematic review of comparative studies where computers gave advice to clinicians on the most appropriate drug dose. Search methods used were standard for the Cochrane Collaboration on Effective Professional Practice.SubjectsComparative studies conducted worldwide and published between 1966 and 1996.ResultsEighteen studies met the inclusion criteria. The drugs studied were theophylline, warfarin, heparin, aminoglycosides, nitroprusside, lignocaine, oxytocin, fentanyl, and midazolam. The computer programs used individualised pharmacokinetic models to calculate the most appropriate dose. Meta-analysis of data from 671 patients showed higher blood concentrations of drug with computer support (effect size 0.69, 95% confidence interval 0.36 to 1.02) and reduced time to achieve therapeutic control (0.44, 0.17 to 0.71). The total dose of drug used was unchanged, and there were fewer unwanted effects of treatment. Five of six studies measuring outcomes of care showed benefit from computer assistance.ConclusionsThis review suggests that using computers to determine the correct dose of certain drugs in acute hospital settings is beneficial. Computers may give doctors the confidence to use higher doses when necessary, adjusting the drug dose more accurately to individual patients. Further research is necessary to evaluate the benefits in general use.
Key messages
- This systematic review of studies examining computer support for determining optimum drug dose showed benefits from computer use
- Computer support led to patients having increased blood concentrations of drug, reduced time to achieve therapeutic benefits, and fewer unwanted effects of treatment
- Computer support helps doctors to tailor drug doses more closely to the needs of individual patients
- All the studies took place in hospitals, and further research is needed to determine the risks and benefits of widespread use of computer support, particularly in general practice, where most prescribing takes place
14.
Kumar Anil Thakur Avinash Panesar Parmjit Singh 《Reviews in Environmental Science and Biotechnology》2019,18(4):823-853
Reviews in Environmental Science and Bio/Technology - In this current review article, a significant number of published articles were reviewed in order to provide comprehensive literature... 相似文献
15.
Else Boken 《Plant and Soil》1970,33(1-3):645-652
Summary In pot experiments with a phosphorus-deficient soil and four barley varieties, Kenia, Maja, Bonus, and Pallas, receiving increasing
amounts of phosphorus, it was found that the order of susceptibility to phosphorus deficiency of the varieties was the same
for grain as for grain + straw, when the ranking was based on the percentage decrease in dry matter yield as a result of phosphorus
deficiency based on the maximum obtained dry matter yield. Estimations of the maximum phosphorus utilization quotients of
dry matter yield of grain + straw graduated the susceptibility to phosphorus deficiency of the varieties in the same order. 相似文献
16.
Ralph R. Maurer 《Theriogenology》1978,9(1):45-68
This article reviews the literature on freezing mammalian oocytes and embryos, with emphasis on embryos of domestic animals. Mammalian embryos must be stored in a quiescent state to retain viability for long periods. This has been accomplished by freezing and storing the embryos at ?196°C. To freeze embryos, a cryoprotectant like dimethyl sulfoxide (DMSO) or glycerol was required, slow cooling (0.1 to 2.0°C/min) and warming (1 to 50°C/min) rates were used, enucleation or seeding the freezing medium was a necessity, and stepwise addition and removal of the cryoprotectant at room temperature seemed to be beneficial. Using the above parameters embryos have been frozen and stored at ?196°C for several years and upon thawing and transfer to a suitable recipient, viable offspring have developed. Initially embryo viability was low after freezing-thawing, but with refinement of freezing-thawing techniques has increased sufficiently so that freezing embryos is no longer a laboratory technique, but is applicable to field use. 相似文献
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Muhammad Akhlaq Tarek R. Sheltami Hussein T. Mouftah 《Reviews in Environmental Science and Biotechnology》2012,11(3):305-322
Sand and dust storms (SDSs) are common phenomena in many parts of the world, which offer serious hazards to the environment, economy and health. An early warning of the approaching SDS would allow people to take precautionary measures and help minimize its terrible effects on the daily life. This requires continuous monitoring of the fugitive dust, sandstorms and movements of sandbanks in a certain area. Several technologies for monitoring of the dust and other environmental changes are available, such as lookout-tower, video-surveillance, sensory information, satellite imagery, unmanned aerial vehicle and hybrid approaches. A particular technology is suitable only for detecting the certain types of SDS, but a hybrid approach can detect many types of SDS. In this paper, we provide a quick review of the techniques and technologies for SDS monitoring. We provide an overview of the data requirements, dust modeling and techniques for SDS detection and prediction. We also summarize, classify and compare different technologies for SDS detection and prediction, and propose that a hybrid approach consisting of satellite imagery and wireless sensor networks is best suitable for detecting and predicting SDSs of all types. 相似文献
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Cluster Computing - Cloud and IoT applications have inquiring effects that can strongly influence today’s ever-growing internet life along with necessity to resolve numerous challenges for... 相似文献