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471.
OEIS is an extremely rare constellation of malformations, which includes omphalocele, exstrophy of cloaca, imperforate anus, and spinal defect. We report here autopsy findings in a case of OEIS complex, which apart from the major anomalies of the complex had bilateral club foot that is, congenital talipes equinovarus, right hydroureter, and body stalk anomaly. The umbilical cord was absent, and the umbilical vessels were embedded in an amniotic sheet, which connected the skin margin of the anterior body wall defect to the placenta, this feature being the hallmark of limb body wall complex (LBWC). This case further supports the view that OEIS and LBWC represent a continuous spectrum of abnormalities rather than separate conditions and may share a common etiology and pathogenetic mechanism as proposed by some authors.  相似文献   
472.
Articular cartilage posesses unique material properties due to a complex depth-dependent composition of sub-components. Raman spectroscopy has proven valuable in quantifying this composition through cartilage cross-sections. However, cross-sectioning requires tissue destruction and is not practical in situ. In this work, Raman spectroscopy-based multivariate curve resolution (MCR) was employed in porcine cartilage samples (n = 12) to measure collagen, glycosaminoglycan, and water distributions through the surface for the first time; these were compared against cross-section standards. Through the surface Raman measurements proved reliable in predicting composition distribution up to a depth of approximately 0.5 mm. A fructose-based optical clearing agent (OCA) was also used in an attempt to further improve depth of resolution of this measurement method. However, it did not; mainly due to a high-spectral overlap with the Raman spectra of main cartilage sub-components. This measurement technique potentially could be used in situ, to better understand the etiology of joint diseases such as osteoarthritis (OA).  相似文献   
473.
Modellers of large-scale genome rearrangement events, in which segments of DNA are inverted, moved, swapped, or even inserted or deleted, have found a natural syntax in the language of permutations. Despite this, there has been a wide range of modelling choices, assumptions and interpretations that make navigating the literature a significant challenge. Indeed, even authors of papers that use permutations to model genome rearrangement can struggle to interpret each others’ work, because of subtle differences in basic assumptions that are often deeply ingrained (and consequently sometimes not even mentioned). In this paper, we describe the different ways in which permutations have been used to model genomes and genome rearrangement events, presenting some features and limitations of each approach, and show how the various models are related. This paper will help researchers navigate the landscape of permutation-based genome rearrangement models and make it easier for authors to present clear and consistent models.  相似文献   
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Blood is a dense suspension of soft non-Brownian cells of unique importance. Physiological blood flow involves complex interactions of blood cells with each other and with the environment due to the combined effects of varying cell concentration, cell morphology, cell rheology, and confinement. We analyze these interactions using computational morphological image analysis and machine learning algorithms to quantify the non-equilibrium fluctuations of cellular velocities in a minimal, quasi-two-dimensional microfluidic setting that enables high-resolution spatio-temporal measurements of blood cell flow. In particular, we measure the effective hydrodynamic diffusivity of blood cells and analyze its relationship to macroscopic properties such as bulk flow velocity and density. We also use the effective suspension temperature to distinguish the flow of normal red blood cells and pathological sickled red blood cells and suggest that this temperature may help to characterize the propensity for stasis in Virchow''s Triad of blood clotting and thrombosis.  相似文献   
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Effect of addition of sodium alginate (alginate) to milk on the storage modulus (G′), water holding capacity (WHC) and hardness of rennet gels was evaluated as a function of alginate (0–0.25 g/100 g) and fat (0.5–3.0 g/100 g) concentrations. There was a significant effect of alginate addition on ionic calcium in milk and whey (Ca2+), and particle size distribution in alginate added milk. Results showed a positive correlation of alginate with WHC; negative correlation of alginate and positive correlation of fat with G′; and negative correlation of interaction of fat and alginate with gel hardness of rennet gels. Hence, the rennet gels with lower fat content and higher added alginate tended to be softer due to the high water holding capacity of the alginate particles.  相似文献   
478.
Of 101Escherichia coli isolates from raw meat, food handlers and equipment 24.8% showed enterotoxigenicity, 22.7% surface hydrophobicity and there was a high incidence of resistance towards metal ions such as mercury, cadmium and silver. Only 6% of the strains were colicin producers. Significant statistical correlation was observed between enterotoxin production and cadmium and mercury ion resistance.
Résumé Center une souches d'Escherichia coli ont été, isolées de viandes crues, de manutantionneurs de nourriture et d'equipement de boucherie. Elles exhibent une enterotoxigénécité à concurrence de 24.8%, une hydrophobicité de surface à concurrence de 22.7%. Il y a une grande fréquence de résistance vis-à-vis d'ions métalliques comme le mercure, le cadmium et l'argent. A peine 6% des souches sont productrices de colicine. Il y a une corrélation significative sur le plan statistique entre la production d'enterotoxines et la résistance aux ions cadmium et mercure.
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480.
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