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1.
This study aimed to evaluate a complete nutritional composition in the seeds Quercus virginiana to compare this nutritional composition with three Mediterranean Quercus species. We analyzed the seed morphometry, proximate composition, phytochemicals, and antioxidant capacity. The seed of Q. virginiana presented the smaller seed size and weight, while Q. suber presented the highest values. Moreover, Q. virginiana seeds showed the highest amounts of sugar and total lipids, digestibility, energy, palmitic acid, and stearic acid. On the other hand, Q. virginiana seeds showed the lowest values of linoleic acid. Moreover, Q. coccifera seeds presented the highest total phenolics and flavonoids contents and antioxidant activity. The clustering analysis revealed a significant similarity in seed morphometry and nutritional composition between the Mediterranean Q. ilex and Q. suber, grouping with the American Q. virginiana, but to a considerable distance; by contrast, the Mediterranean Q. coccifera was the most distant in the clustering analysis. The content of phenolics and flavonoids and digestibility value were the variables that contributed to the separation to a greater extent in the clustering of the four species. The nutritional and biological activity assessment of plant seed may be considered as an essential mission to find new sustainable sources and novel chemical agents. In this sense, Quercus seeds may be an alternative and a competitive food source for the agri-food industry.  相似文献   
2.
本文对野生状态下生活的46只四爪陆龟的背板长度、背板宽度、壳高和腹板长度测量数据的分析研究表明,在四爪陆龟形体生长中,背板长度的增长速率基本上与腹板长度的增长速率相同,并具较高的相关性,背板宽度的增长速率高于壳高的增长速率,因此四爪陆龟龟壳显得较为平坦,计算结果表明,四爪陆龟背板长度与腹板长度的形体生长方程为:y=0.93x′+0.10,背板宽度与腹板长度的形态生长方程为y′=1.08x′-0.14,壳高与腹板长度的形体生长方程为:y′=0.88x′+0.46.  相似文献   
3.
Structural neuroimaging studies are of great interest for neuroscientists, which are reflected in the rising number of papers using voxel-based morphometry (VBM). One major step in VBM is the transformation of images to a standard template, a spatial normalization necessary to ensure that homologous regions are compared while interindividual characteristics are maintained. Templates can be created in different ways, and this may affect the likelihood that differences in gray/white matter density between groups are detected. However, studies investigating the interaction of normalization template and VBM accuracy are sparse. Existing work is based on patient–control group comparisons, and the emerging results are inconclusive. The present paper therefore used simulated atrophy in a simplified one-lesion model to systematically study template effects of VBM analyses implemented in SPM. This allowed us to characterize template-specific biases in reference to a set of prespecified parameters of anatomical difference. The data suggest that the likelihood of correctly detecting the prespecified lesion is modulated by the normalization template. Thereby, the relationship between template-related VBM accuracy and specific group/study characteristics is complex, and there does not appear to be one ‘best template.’ Our data show that template effects are critical and clearly suggest that the choice of template needs careful consideration in relation to the specific research question and study constraints.  相似文献   
4.
Glaucoma is an optic neuropathy affecting the entire visual system. The understanding of the glaucoma mechanism and causes remains unresolved. Diffusion tensor imaging (DTI) has been used to analyze the optic nerve and optic radiation showing global fiber abnormalities associated with glaucoma. Nevertheless, the complex structure of the optic radiation and the limitations of DTI make the localization of the glaucoma effect a difficult task. The aim of this work is to establish a framework for the determination of the local changes of the optic radiation due to glaucoma using DTI. The proposed system utilizes a semiautomated algorithm to produce an efficient identification of the optic radiation. Segmented optic radiations are transformed to a unified space using shape-based nonrigid registration. Using the deformation fields that resulted from the registration, the maps of the diffusion tensor-derived parameters are transformed to the unified space. This allows for statistical voxel-wise analysis to produce significant abnormality maps. The proposed system is applied to a group of 13 glaucoma patients and a normal control group of 10 subjects. The groups are age matched to eliminate the age effect on the analysis. Diffusion-related parameters (axial, radial and mean diffusivities) and an anisotropy index (fractional anisotropy) are studied. The anisotropy analysis indicates that the majority of the significant voxels show decreased fractional anisotropy in the glaucoma patients compared with the control group. In addition, the significant regions are mainly distributed in the middle (in reference to anterior–posterior orientation) of the optic radiation. Glaucoma subjects have increased radial diffusivity and mean diffusivity significant voxels with a main concentration in the proximal part of the right optic radiation. The proposed analysis provides a framework to capture the significant local changes of the optic radiation due to glaucoma. The preliminary analysis suggests that the glaucomatous optic radiation may suffer from localized white matter degeneration. The framework facilitates further studies and understanding of the pathophysiology of glaucoma.  相似文献   
5.
The large-scale and label-free molecular characterization of single cells in their natural tissue habitat remains a major challenge in molecular biology. We present a method that integrates morphometric image analysis to delineate and classify individual cells with their single-cell-specific molecular profiles. This approach provides a new means to study spatial biological processes such as cancer field effects and the relationship between morphometric and molecular features.  相似文献   
6.
Deformation-based morphometry (DBM) is a widely used method for characterizing anatomical differences across groups. DBM is based on the analysis of the deformation fields generated by nonrigid registration algorithms, which warp the individual volumes to a DBM atlas. Although several studies have compared nonrigid registration algorithms for segmentation tasks, few studies have compared the effect of the registration algorithms on group differences that may be uncovered through DBM. In this study, we compared group atlas creation and DBM results obtained with five well-established nonrigid registration algorithms using 13 subjects with Williams syndrome and 13 normal control subjects. The five nonrigid registration algorithms include the following: (1) the adaptive bases algorithm, (2) the image registration toolkit, (3) The FSL nonlinear image registration tool, (4) the automatic registration tool, and (5) the normalization algorithm available in Statistical Parametric Mapping (SPM8). Results indicate that the choice of algorithm has little effect on the creation of group atlases. However, regions of differences between groups detected with DBM vary from algorithm to algorithm both qualitatively and quantitatively. Some regions are detected by several algorithms, but their extent varies. Others are detected only by a subset of the algorithms. Based on these results, we recommend using more than one algorithm when performing DBM studies.  相似文献   
7.
The purpose of this study was to determine correlations among disease progression, diffusion abnormalities in the posterior cingulum and hippocampal volume in patients with Alzheimer's disease (AD). We studied 25 AD patients by neuropsychological testing, including the Mini-Mental State Examination (MMSE), and by magnetic resonance imaging, including diffusion tensor imaging (DTI) and high-resolution three-dimensional T1-weighted imaging. The MMSE score was used as an indicator of disease progression. Diffusion tensor tractography of the posterior cingulum was generated from the DTI; mean diffusivity (MD) and fractional anisotropy (FA) were measured in co-registered voxels along the posterior cingulum. Hippocampal volume was measured using automated voxel-based morphometry. The relationships among MMSE score, hippocampal volume and MD and FA of the posterior cingulum were evaluated by bivariate correlation analysis. MD in the posterior cingulum correlated significantly with the MMSE score. No significant correlation was seen between FA and MMSE score and between hippocampal volume and MMSE score, FA or MD. Our results suggest that MD in the posterior cingulum is a more sensitive indicator of progression of AD than FA of the posterior cingulum and hippocampal volume.  相似文献   
8.
The large‐scale and label‐free molecular characterization of single cells in their natural tissue habitat remains a major challenge in molecular biology. We present a method that integrates morphometric image analysis to delineate and classify individual cells with their single‐cell‐specific molecular profiles. This approach provides a new means to study spatial biological processes such as cancer field effects and the relationship between morphometric and molecular features.  相似文献   
9.
The effect of effective microorganisms (EM) on internal organ morphology, intestinal morphometry, and serum biochemical activity in Japanese quails under Clostridium perfringens challenge was determined. After 30 days of EM addition, one group of quails was orally inoculated with Clostridium perfringens. The second group did not receive EM and was inoculated with C. perfringens. In the gut, EM supplementation reduced the number of lesions, enhanced gut health, and protected the mucosa from pathogenic bacteria. EM showed an anti-inflammatory effect and fewer necrotic lesions in villi. In the internal organs, EM showed a protective effect against a typical lesion of C. perfringens infection. Necrosis and degeneration of the hepatocytes, necrosis of bile ducts, and bile duct proliferation were more severe in the infected group without EM. Morphometric evaluation showed significantly higher villi in the jejunum after EM addition. A greater crypt depth was observed in the C. perfringens group. Biochemical analysis of the blood indicated lower cholesterol on the 12th day of the experiment and between-group differences in total protein, lactate dehydrogenase (LDH), and albumin levels in the EM group. Further studies are needed to improve EM activity against pathologic bacteria as a potential alternative to antibiotics and to develop future natural production systems.  相似文献   
10.
The heat shock protein (HSP) 70 is considered the main hallmark in preclinical studies to stain the peri-infarct region defined area penumbra in preclinical models of brain ischemia. This protein is also considered as a potential disease modifier, which may improve the outcome of ischemic damage. In fact, the molecule HSP70 acts as a chaperonine being able to impact at several level the homeostasis of neurons. Despite being used routinely to stain area penumbra in light microscopy, the subcellular placement of this protein within area penumbra neurons, to our knowledge, remains undefined. This is key mostly when considering studies aimed at deciphering the functional role of this protein as a determinant of neuronal survival. The general subcellular placement of HSP70 was grossly reported in studies using confocal microscopy, although no direct visualization of this molecule at electron microscopy was carried out. The present study aims to provide a direct evidence of HSP70 within various subcellular compartments. In detail, by using ultrastructural morphometry to quantify HSP70 stoichiometrically detected by immuno-gold within specific organelles we could compare the compartmentalization of the molecule within area penumbra compared with control brain areas. The study indicates that two cell compartments in control conditions own a high density of HSP70, cytosolic vacuoles and mitochondria. In these organelles, HSP70 is present in amount exceeding several-fold the presence in the cytosol. Remarkably, within area penumbra a loss of such a specific polarization is documented. This leads to the depletion of HSP70 from mitochondria and mostly cell vacuoles. Such an effect is expected to lead to significant variations in the ability of HSP70 to exert its physiological roles. The present findings, beyond defining the neuronal compartmentalization of HSP70 within area penumbra may lead to a better comprehension of its beneficial/detrimental role in promoting neuronal survival.  相似文献   
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