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21.
Design, Validation, and Application of a Seven-Strain Staphylococcus aureus PCR Product Microarray for Comparative Genomics 下载免费PDF全文
22.
Elinor McKone Sacha Stokes Jia Liu Sarah Cohan Chiara Fiorentini Madeleine Pidcock Galit Yovel Mary Broughton Michel Pelleg 《PloS one》2012,7(10)
Other-race and other-ethnicity effects on face memory have remained a topic of consistent research interest over several decades, across fields including face perception, social psychology, and forensic psychology (eyewitness testimony). Here we demonstrate that the Cambridge Face Memory Test format provides a robust method for measuring these effects. Testing the Cambridge Face Memory Test original version (CFMT-original; European-ancestry faces from Boston USA) and a new Cambridge Face Memory Test Chinese (CFMT-Chinese), with European and Asian observers, we report a race-of-face by race-of-observer interaction that was highly significant despite modest sample size and despite observers who had quite high exposure to the other race. We attribute this to high statistical power arising from the very high internal reliability of the tasks. This power also allows us to demonstrate a much smaller within-race other ethnicity effect, based on differences in European physiognomy between Boston faces/observers and Australian faces/observers (using the CFMT-Australian). 相似文献
23.
Sarah A. Nowak 《Biophysical journal》2009,96(7):2624-2636
Enveloped viruses enter host cells either through endocytosis, or by direct fusion of the viral envelope and the membrane of the host cell. However, some viruses, such as HIV-1, HSV-1, and Epstein-Barr can enter a cell through either mechanism, with the choice of pathway often a function of the ambient physical chemical conditions, such as temperature and pH. We develop a stochastic model that describes the entry process at the level of binding of viral glycoprotein spikes to cell membrane receptors and coreceptors. In our model, receptors attach the cell membrane to the viral membrane, while subsequent binding of coreceptors enables fusion. The model quantifies the competition between fusion and endocytotic entry pathways. Relative probabilities for each pathway are computed numerically, as well as analytically in the high viral spike density limit. We delineate parameter regimes in which fusion or endocytosis is dominant. These parameters are related to measurable and potentially controllable quantities such as membrane bending rigidity and receptor, coreceptor, and viral spike densities. Experimental implications of our mechanistic hypotheses are proposed and discussed. 相似文献
24.
Problem Infrequent presentation of patients with eclampsia, leading to staff inexperienced in the condition and untested emergency systems.Design “Fire drill” programme using on-site simulation of patients with eclampsia.Setting Tertiary referral obstetric unit.Key measures for improvement Successful implementation of measures to optimise management of eclampsia.Strategies for change Rapid activation of emergency team after one call, development and dissemination of evidence based protocol for eclampsia, strategically placed “eclampsia boxes,” individual staff feedback and education.Effects of change Efficient and appropriate management of subsequent simulated patients.Lessons learnt On-site simulation can identify and correct potential deficiencies in the care of patients with eclampsia. 相似文献
25.
Sarah L. Appleby Michaelia P. Cockshell Jyotsna B. Pippal Emma J. Thompson Jeffrey M. Barrett Katie Tooley Shaundeep Sen Wai Yan Sun Randall Grose Ian Nicholson Vitalina Levina Ira Cooke Gert Talbo Angel F. Lopez Claudine S. Bonder 《PloS one》2012,7(11)
Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133+ population of non-adherent endothelial forming cells (naEFCs) which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38) together with mature endothelial cell markers (VEGFR2, CD144 and CD31). These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8) or myeloid markers (CD11b and CD14) which distinguishes them from ‘early’ endothelial progenitor cells (EPCs). Functional studies demonstrated that these naEFCs (i) bound Ulex europaeus lectin, (ii) demonstrated acetylated-low density lipoprotein uptake, (iii) increased vascular cell adhesion molecule (VCAM-1) surface expression in response to tumor necrosis factor and (iv) in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs). Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM)-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis. 相似文献
26.
Harbor seal ( Phoca vitulina ) haul-out site use may be affected by natural or anthropogenic factors. Here, we use an 11-yr (1997–2007) study of a seal colony located near a mariculture operation in Drakes Estero, California, to test for natural (El Niño-Southern Oscillation (ENSO), density-dependence, long-term trends) and anthropogenic (disturbance or displacement related to oyster production activities) factors that may influence the use of haul-out subsites. Annual mariculture related seal disturbance rates increased significantly with increases in oyster harvest ( r s = 0.55). Using generalized linear models (GLMs) ranked by best fit and Akaike's Information Criteria, ENSO and oyster production (as a proxy for disturbance/displacement) best explained the patterns of seal use at all three subsites near the mariculture operations, with effects being stronger at the two subsites closest to operations. Conversely, density-dependence and linear trend effects poorly explained the counts at these subsites. We conclude that a combination of ENSO and mariculture activities best explain the patterns of seal haul-out use during the breeding/pupping season at the seal haul-out sites closest to oyster activities. 相似文献
27.
28.
Sarah O. Makled Amira M. Hamdan Abdel-Fattah M. El-Sayed 《Probiotics and antimicrobial proteins》2020,12(2):365-374
A 50-day feeding trial was conducted to evaluate the effects of dietary supplementation of a novel marine psychrotrophic bacterium, Psychrobacter maritimus 相似文献
29.
Although seedling herbivory is an important selective filter in many plant communities, how and why seedlings are selected
is poorly understood. Here, we examined the putative role of herbivore olfaction in dictating seedling selection. Using a
Y-tube olfactometer we compared snail (Helix aspersa) preference for pellets derived from 14-day-old macerated seedlings of nine European grassland (‘Test’) species against standard
(‘Control’) pellets derived from lettuce. Snail movement towards ‘Test’ pellets was strongly correlated with seedling acceptability
(Pearson’s r
2 = 0.86, P > 0.01) and where snails exhibited a positive choice for the ‘Test’ species, the choice was made more quickly for highly
acceptable species (r
2 = 0.86, P > 0.01). In elucidating a link between seedling acceptability and olfactory response to macerated seedlings, our study suggests
that even from an early ontogenetic stage plant selection by snails may be governed by olfactory cues. This finding highlights
the need for research on the role of plant volatiles in plant–herbivore interactions to consider more fully interactions operating
at the seedling stage. 相似文献
30.
Spliceosome-targeted therapies trigger an antiviral immune response in triple-negative breast cancer
Elizabeth A. Bowling Jarey H. Wang Fade Gong William Wu Nicholas J. Neill Ik Sun Kim Siddhartha Tyagi Mayra Orellana Sarah J. Kurley Rocio Dominguez-Vidaña Hsiang-Ching Chung Tiffany Y.-T. Hsu Julien Dubrulle Alexander B. Saltzman Heyuan Li Jitendra K. Meena Gino M. Canlas Srinivas Chamakuri Thomas F. Westbrook 《Cell》2021,184(2):384-403.e21