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951.
Bryan F. J. Manly 《Population Ecology》1987,29(1):119-127
A linear regression method that allows survival rates to vary from stage to stage is described for the analysis of stage-frequency data. It has advantages over previously suggested methods since the calculations are not iterative, and it is not necessary to have independent estimates of stage durations, numbers entering stages, or the rate of entry to stage 1. Simulation is proposed to determine standard errors for estimates of population parameters, and to assess the goodness of fit of models. 相似文献
952.
Leukemia inhibitory factor (LIF) is a pleiotropic cytokine with several functions in health and disease ranging from inflammation to cancer. LIF is also a potential target and/or therapeutic agent for diseases such as multiple sclerosis, stroke and even psychological disorders, where the function of LIF as a neurotrophic factor has only recently been explored. In recent years, a limited number of LIF clinical trials have been completed, which partially explains the shortage of effective applications as a therapeutic agent. With the increasing interest from biotechnology companies producing recombinant LIF, this status quo will certainly change, and the potential impact of LIF in terms of disease diagnosis, treatment and management will be realized. 相似文献
953.
The discovery of a new exotic insect herbivore triggers responses from biosecurity agencies, one of which is the decision of whether or not to attempt eradication. Rapid determination of the host range of the new invader is necessary, but when sap‐sucking insects are first collected from plants, the lack of visible signs of feeding damage makes it difficult to determine their host status. We investigated the Electrical Penetration Graph (EPG‐DC) technique as tool to assess host range of a xylem sap‐feeding invader, using Carystoterpa fingens (Hemiptera: Aphrophoridae), a New Zealand endemic xylem feeder, as a model insect. Real‐time probing and feeding events over a 12‐h recording period were compared for adult C. fingens on 18 plant species. Hebe azure, a known host, was designated the ‘reference plant species’ against which events on all other plants were statistically compared. EPG waveforms were categorized on their amplitude, frequency, voltage and electrical origin, and six parameters (time taken to first probe, time to first xylem ingestion from first probe, total probing time, number of xylem‐ingesting events, duration of the longest xylem‐ingesting event and total xylem ingestion time) were measured. The total xylem ingestion period (i.e. the actual feeding period) on each plant species expressed as a percentage of total probing time was considered the best parameter for comparing the host status of plants with H. azure. Although the EPG data overestimated the actual host range of C. fingens, we consider that they provided a reasonable first guide to the potential host status of the unknown plants, and so might usefully be used to rapidly assess whether a plant from which a new invader was collected was a host, or whether the association was merely incidental. 相似文献
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Alex van Belkum Sonia Chatellier Victoria Girard David Pincus Parampal Deol Wm Michael Dunne Jr 《Expert review of proteomics》2015,12(6):595-605
Although classical proteomic approaches are still used regularly in routine clinical diagnostic procedures, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) MS has recently moved into diagnostic microbiology laboratories. MALDI-TOF MS is currently replacing phenotypic microbial identification. Many laboratories now use MALDI-TOF MS for its high efficiency, both from a diagnostic and a cost-per-analysis point of view. The US FDA has now cleared two of the commercially available systems for in vitro diagnostics. This will further spark development of MS applications in antimicrobial susceptibility testing and epidemiology. This review summarizes the state of affairs of MALDI-TOF MS in clinical microbiology; however, this is an active field of research subject to rapid evolution. We emphasize assessment of the clinical relevance and studies focusing on data obtained through comparative analyses of different MALDI-TOF MS instrumentation and multicenter validation studies. The future of MALDI-TOF MS, including antimicrobial susceptibility testing and epidemiological typing, is also highlighted. 相似文献
959.
Review: domestic animal forensic genetics – biological evidence,genetic markers,analytical approaches and challenges
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S. Kanthaswamy 《Animal genetics》2015,46(5):473-484
This review highlights the importance of domestic animal genetic evidence sources, genetic testing, markers and analytical approaches as well as the challenges this field is facing in view of the de facto ‘gold standard’ human DNA identification. Because of the genetic similarity between humans and domestic animals, genetic analysis of domestic animal hair, saliva, urine, blood and other biological material has generated vital investigative leads that have been admitted into a variety of court proceedings, including criminal and civil litigation. Information on validated short tandem repeat, single nucleotide polymorphism and mitochondrial DNA markers and public access to genetic databases for forensic DNA analysis is becoming readily available. Although the fundamental aspects of animal forensic genetic testing may be reliable and acceptable, animal forensic testing still lacks the standardized testing protocols that human genetic profiling requires, probably because of the absence of monetary support from government agencies and the difficulty in promoting cooperation among competing laboratories. Moreover, there is a lack in consensus about how to best present the results and expert opinion to comply with court standards and bear judicial scrutiny. This has been the single most persistent challenge ever since the earliest use of domestic animal forensic genetic testing in a criminal case in the mid‐1990s. Crime laboratory accreditation ensures that genetic test results have the courts’ confidence. Because accreditation requires significant commitments of effort, time and resources, the vast majority of animal forensic genetic laboratories are not accredited nor are their analysts certified forensic examiners. The relevance of domestic animal forensic genetics in the criminal justice system is undeniable. However, further improvements are needed in a wide range of supporting resources, including standardized quality assurance and control protocols for sample handling, evidence testing, statistical analysis and reporting that meet the rules of scientific acceptance, reliability and human forensic identification standards. 相似文献
960.
目的:PAD方案已成为目前多发性骨髓瘤(MM)治疗的一线方案,国内外就其疗效和不良反应发生均有报道,本实验旨在观察并探讨PAD方案治疗我中心初诊多发性骨髓瘤患者的疗效和不良反应,为临床工作提供参考。方法:我科75例初诊多发性骨髓瘤患者给予PAD方案4-6疗程,评估疗效及不良反应。结果:75例患者接受PAD方案化疗,四疗程后总有效率(CR+VGPR+PR)为73.3%,其中CR 5例,占6.7%,VGPR 12例,占16%,PR 38例,占50.7%;无效例数为20例,占26.7%,其中SD 17例,占22.7%,PD 3例,占4%;1年总生存率为75%,2年总生存率为62.7%。血液学不良反应有白细胞降低34例(45.3%),血小板降低10例(13.3%);非血液学不良反应有周围神经系统症状25例(33.3%),疱疹病毒感染7例(9.3%),消化系统症状15例(20%),乏力14例(18.7%),呼吸系统症状29例(38.7%),激素相关症状3例(4%)。绝大部分患者可以耐受且完成相应化疗疗程。结论:我中心PAD方案疗效令人满意,不良反应可耐受,同国内外报道的疗效反应率相近,不良反应发生率更低,是治疗多发性骨髓瘤的首选方案。 相似文献