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101.
Michael Haslam 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1630)
Animals in captive or laboratory settings may outperform wild animals of the same species in both frequency and diversity of tool use, a phenomenon here termed ‘captivity bias’. Although speculative at this stage, a logical conclusion from this concept is that animals whose tool-use behaviour is observed solely under natural conditions may be judged cognitively or physically inferior than if they had also been tested or observed under controlled captive conditions. In turn, this situation creates a potential problem for studies of the behaviour of extinct members of the human family tree—the hominins—as hominin cognitive abilities are often judged on material evidence of tool-use behaviour left in the archaeological record. In this review, potential factors contributing to captivity bias in primates (including increased contact between individuals engaged in tool use, guidance or shaping of tool-use behaviour by other tool-users and increased free time and energy) are identified and assessed for their possible effects on the behaviour of the Late Pleistocene hominin Homo floresiensis. The captivity bias concept provides one way to uncouple hominin tool use from cognition, by considering hominins as subject to the same adaptive influences as other tool-using animals. 相似文献
102.
ObjectiveTo demonstrate that the use of step-and-shoot (SAS) mode in paediatric cardiac CT angiography (CCTA) is possible at heart rates (HR) greater than 65 bpm, allowing low-dose acquisition with single-source 64-slices CT.MethodsWe retrospectively included 125 paediatric patients (0–6 years). CCTA was performed with SAS at diastolic phase in 31 patients (group D, HR < 65 bpm), at systolic phase in 45 patients (group S, HR ≥ 65 bpm) and with non-gated mode in 49 patients (group NG). Effective dose (ED) and image quality using a 3-grade scoring scale (1, excellent; 2, moderate; 3, insufficient) of group S were compared with group D for coronary examinations and group NG for entire thorax vascular anatomy.ResultsFor coronary indications, median ED was 0.6 mSv in group D versus 0.9 mSv in group S (p < 0.01). For whole thorax indications, median ED was 2.7 mSv in group NG versus 1.1 mSv in group S (p < 0.001). The mean image quality score was (1.4 ± 0.6) points in group D, (1.4 ± 0.7) in group S for coronary indications (p = 0.9), (1.3 ± 0.6) in group S for whole thorax indications and (2.0 ± 0.0) in group NG (p < 0.001).ConclusionSAS mode is feasible in children with HR greater than 65 bpm allowing low-dose CCTA. It provided comparable image quality in systole, compared to diastole. SAS at the systolic phase provided better image quality with less radiation dose compared to non-gated scans for whole thorax examinations. 相似文献
103.
Christopher P. Barkway Rebecca L. Pocock Vladimir Vrba Damer P. Blake 《Journal of visualized experiments : JoVE》2015,(96)
Eimeria species parasites, protozoa which cause the enteric disease coccidiosis, pose a serious threat to the production and welfare of chickens. In the absence of effective control clinical coccidiosis can be devastating. Resistance to the chemoprophylactics frequently used to control Eimeria is common and sub-clinical infection is widespread, influencing feed conversion ratios and susceptibility to other pathogens such as Clostridium perfringens. Despite the availability of polymerase chain reaction (PCR)-based tools, diagnosis of Eimeria infection still relies almost entirely on traditional approaches such as lesion scoring and oocyst morphology, but neither is straightforward. Limitations of the existing molecular tools include the requirement for specialist equipment and difficulties accessing DNA as template. In response a simple field DNA preparation protocol and a panel of species-specific loop-mediated isothermal amplification (LAMP) assays have been developed for the seven Eimeria recognised to infect the chicken. We now provide a detailed protocol describing the preparation of genomic DNA from intestinal tissue collected post-mortem, followed by setup and readout of the LAMP assays. Eimeria species-specific LAMP can be used to monitor parasite occurrence, assessing the efficacy of a farm’s anticoccidial strategy, and to diagnose sub-clinical infection or clinical disease with particular value when expert surveillance is unavailable. 相似文献
104.
N. van Gurp L. J. M. Boonman-De Winter D. W. Meijer Timmerman Thijssen H. E. J. H. Stoffers 《Netherlands heart journal》2013,21(9):399-405
Background
Open access echocardiography has been evaluated in the United Kingdom, but hardly in the Netherlands. The echocardiography service of the SHL-Groep in Etten-Leur was set up independently from the regional hospitals. Cardiologists not involved in the direct care of the participating patients evaluated the echocardiograms taken by ultrasound technicians.Aims
We estimated the reduction in the number of referrals to regional cardiologists, the adherence of the general practitioners (GPs) to the advice of the evaluating cardiologist, GPs’ opinion on the benefit of the echocardiography service and GPs’ adherence to the diagnostic protocol advocated in the Dutch clinical guideline for heart failure.Methods
A prospective cohort study was performed. Patients were included from April 2011 to April 2012 (N = 155). Data from application forms (N = 155), echocardiography results (N = 155) and telephone interviews with GPs (N = 138) were analysed.Results
GPs referred less patients to the cardiologist than they would have done without echocardiography available (92 % vs. 34 %, p < 0.001). They treated more patients by themselves (62 % vs. 10 %, p < 0.001). Most GPs (81 %) followed the advice presented on the echocardiogram result. Most GPs (82 %) found the service had clinical benefit for the patient. Sixty two percent of echocardiography requests met the criteria of the Dutch clinical guideline for heart failure.Conclusion
Open access echocardiography saved referrals to the cardiology department, saved time, and enabled GPs to treat more patients by themselves. Adherence to diagnostic guidelines for heart failure was suboptimal. 相似文献105.
PFN与DHS治疗老年不稳定型股骨粗隆下骨折的疗效分析 总被引:1,自引:0,他引:1
目的:比较PFN与DHS内固定治疗老年不稳定型股骨粗隆下骨折的预后及评其疗效方法:2002年1月至2008年1月我科共收治老年不稳定型股骨粗隆下骨折患者129例,男59例,女70例,年龄51~86岁,平均61.7岁随机选择PFN或DHS内固定,PFN组62例,DHS组67例。比较两组的手术时间、术中出血量、术后第二天CRP值、张力侧出现骨痂时间、骨折愈合时间、Harris评分等6项指标。结果:116例获得13~48个月的随访,平均18.7月,除手术时间及Harris评分无差异外,PFN组在术中出血量、术后第二天CRP值、张力侧出现骨痂时间、骨折平均愈合时间等方面与DHS组比较有显著优势(P<0.05)结论:PFN内固定创伤小、术后并发症率较低,可以成为治疗老年不稳定型股骨粗隆下骨折的主要方法 相似文献
106.
107.
Adam Stonier David Pain Ashley Westlake Nicholas Hutchinson Nina F. Thornhill Suzanne S. Farid 《Biotechnology progress》2013,29(2):368-377
This article describes a decision‐support tool to help pinpoint the potential root causes of sub‐optimal short‐term facility fit issues in biopharmaceutical facilities. This was achieved by creating a tool that integrated stochastic simulation with advanced multivariate statistical analysis. Process fluctuations in product titers in cell culture, step yields, and chromatography eluate volumes were mimicked using Monte Carlo simulation data derived using a stochastic discrete‐event simulation model. The resulting stochastic datasets, with the computed consequences on key metrics such as product mass loss and cost of goods, were examined using advanced multivariate statistical techniques. Principal component analysis combined with clustering algorithms was used to analyze the complex datasets from complete industrial batch processes for biopharmaceuticals. The challenge of visualizing the multidimensional nature of the dataset was addressed using hierarchical and k‐means clustering as well as stacked parallel co‐ordinate plots to help identify process fingerprints and characteristics of clusters leading to sub‐optimal facility fit issues. Industrially‐relevant case studies are presented that focus on technology transfer challenges for therapeutic antibodies moving from early phase to late phase clinical trials. The case study details how sub‐optimal facility fit can be alleviated by allocating alternative product pool tanks. The impact of this operational change is then assessed by reviewing an updated process fingerprint. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 368–377, 2013 相似文献
108.
D. M. Fragaszy D. Biro Y. Eshchar T. Humle P. Izar B. Resende E. Visalberghi 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1630)
All investigated cases of habitual tool use in wild chimpanzees and capuchin monkeys include youngsters encountering durable artefacts, most often in a supportive social context. We propose that enduring artefacts associated with tool use, such as previously used tools, partly processed food items and residual material from previous activity, aid non-human primates to learn to use tools, and to develop expertise in their use, thus contributing to traditional technologies in non-humans. Therefore, social contributions to tool use can be considered as situated in the three dimensions of Euclidean space, and in the fourth dimension of time. This notion expands the contribution of social context to learning a skill beyond the immediate presence of a model nearby. We provide examples supporting this hypothesis from wild bearded capuchin monkeys and chimpanzees, and suggest avenues for future research. 相似文献
109.
Andrelly Martins-José 《Bioinformation》2013,9(14):750-751
Sliding Box Docking is a program that manages simulations of ligand docking at different defined positions of a three-dimensional
DNA structure. The procedure is similar to inverse docking, which is a method that performs docking simulations of a single
ligand in the active sites of different targets. Sliding Box Docking manages docking simulations of one ligand into a box that slides
along the DNA helix axis in regular steps. For each box position a score is calculated using the separate Autodock Vina software,
and the results are automatically plotted. The evaluation of ligand interaction at different DNA locations can highlight the
specificity of ligands for different DNA- sequences. When assessing the affinity between ligans AT base pairs, results for docking
simulations with a test set that included berenil, distamycin, hoechst 33258, and netropsin were as expected, agreeing well with
affinities previously described in the literature.
Availability
Binaries are freely available at https://sourceforge.net/projects/slidingboxdocki 相似文献110.
Jiang X Sidhu R Porter FD Yanjanin NM Speak AO te Vruchte DT Platt FM Fujiwara H Scherrer DE Zhang J Dietzen DJ Schaffer JE Ory DS 《Journal of lipid research》2011,52(7):1435-1445
Niemann-Pick type C1 (NPC1) disease is a rare, progressively fatal neurodegenerative disease for which there are no FDA-approved therapies. A major barrier to developing new therapies for this disorder has been the lack of a sensitive and noninvasive diagnostic test. Recently, we demonstrated that two cholesterol oxidation products, specifically cholestane-3β,5α,6β-triol (3β,5α,6β-triol) and 7-ketocholesterol (7-KC), were markedly increased in the plasma of human NPC1 subjects, suggesting a role for these oxysterols in diagnosis of NPC1 disease and evaluation of therapeutics in clinical trials. In the present study, we describe the development of a sensitive and specific LC-MS/MS method for quantifying 3β,5α,6β-triol and 7-KC human plasma after derivatization with N,N-dimethylglycine. We show that dimethylglycine derivatization successfully enhanced the ionization and fragmentation of 3β,5α,6β-triol and 7-KC for mass spectrometric detection of the oxysterol species in human plasma. The oxysterol dimethylglycinates were resolved with high sensitivity and selectivity, and enabled accurate quantification of 3β,5α,6β-triol and 7-KC concentrations in human plasma. The LC-MS/MS assay was able to discriminate with high sensitivity and specificity between control and NPC1 subjects, and offers for the first time a noninvasive, rapid, and highly sensitive method for diagnosis of NPC1 disease. 相似文献