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排序方式: 共有2340条查询结果,搜索用时 31 毫秒
1.
Karina Polak Beata Bergler-Czop Micha Szczepanek Kamila Wojciechowska Aleksandra Frtczak Norbert Kiss 《International journal of molecular sciences》2021,22(9)
Psoriasis is a chronic, immune-mediated inflammatory disease that affects around 125 million people worldwide. Several studies concerning the gut microbiota composition and its role in disease pathogenesis recently demonstrated significant alterations among psoriatic patients. Certain parameters such as Firmicutes/Bacteroidetes ratio or Psoriasis Microbiome Index were developed in order to distinguish between psoriatic and healthy individuals. The “leaky gut syndrome” and bacterial translocation is considered by some authors as a triggering factor for the onset of the disease, as it promotes chronic systemic inflammation. The alterations were also found to resemble those in inflammatory bowel diseases, obesity and certain cardiovascular diseases. Microbiota dysbiosis, depletion in SCFAs production, increased amount of produced TMAO, dysregulation of the pathways affecting the balance between lymphocytes populations seem to be the most significant findings concerning gut physiology in psoriatic patients. The gut microbiota may serve as a potential response-to-treatment biomarker in certain cases of biological treatment. Oral probiotics administration as well as fecal microbial transplantation were most reported in bringing health benefits to psoriatic patients. However, the issue of psoriatic bacterial gut composition, its role and healing potential needs further investigation. Here we reviewed the literature on the current state of the relationship between psoriasis and gut microbiome. 相似文献
2.
Sunil K. Sinha Paul W. Fieguth & Maria A. Polak 《Computer-Aided Civil and Infrastructure Engineering》2003,18(2):95-112
Pipeline surface defects such as cracks cause major problems for asset managers, particularly when the pipe is buried under the ground. The manual inspection of surface defects in the underground pipes has a number of drawbacks, including subjectivity, varying standards, and high costs. An automatic inspection system using image processing and artificial intelligence techniques can overcome many of these disadvantages and offer asset managers an opportunity to significantly improve quality and reduce costs. This article presents a system for the application of computer vision techniques to the automatic assessment of the structural condition of underground pipes. The algorithm consists of image preprocessing, a sequence of morphological operations to accurately extract pipe joints and laterals (where smaller pipe is connected to main bigger pipe), and statistical filters for detection of surface cracks in the pipeline network. The proposed approach can be completely automated and has been tested on over 1,000 scanned images of underground pipes from major cities in North America. 相似文献
3.
Central Europe experienced catastrophic rainfalls and flooding in 2010. This paper discusses a decommissioned shaft that was flooded by surface water, which led to displacement of shaft backfill and an inrush of large amounts of water into an underground pumping station. The weather conditions for the period preceding the inrush, the hydrogeological conditions, the quantity of water that entered the mine dewatering systems, and the underground hydraulic connections are all described. Uncontrolled inflow of water as a cause of backfill saturation and the hazard for active underground infrastructure were analysed. A need to rebuild damaged infrastructure was identified. The case study highlights the need to improve underground mine closure requirements to ensure safe conditions above ground, particularly in densely populated areas. 相似文献
4.
The aim of this study was to determine whether supplemental addition of coenzyme Q10 and ascorbic acid or α-tocopherol, either alone or together, can prevent oxidative damage in chicken liver pâté, as reflected by reduced formation of cholesterol oxidation products (COPs) and by preservation of sensorial quality. Separate groups of chicken liver pâtés had no supplements (control) or were supplemented with coenzyme Q10 (0.2 g/kg) and either ascorbic acid (2 g/kg) or α-tocopherol (0.2 g/kg), or both. All products were pasteurised (82 °C) or sterilised (121 °C). Four COPs were found: 7α-, 7β-, 20α- and 25-hydroxycholesterol. The COP radical scavenger function of coenzyme Q10 (control, 5.16 mg/kg; plus Q10, 3.94 mg/kg) and the synchronous actions of coenzyme Q10 and α-tocopherol (2.6 mg/kg) were confirmed in sterilised pâtés. Generally, in pasteurised and sterilised pâtés, the most efficient scavenger function was with ascorbic acid either alone or together with α-tocopherol, where the formation of COPs was below the limit of detection. An increase of 1.9 mg/kg in COP production during heating was also seen in samples without added antioxidants. There was a weak interdependence between the content of COPs and the sensory parameters of the pâté. For addition of antioxidants, in the pasteurised pâté, colour and smell were slightly improved, but flavour deteriorated; in the sterilised pâté, colour was slightly worse, with a more tender texture. Overall, instrumentally measured colour and sensory properties (except texture) showed no significant differences between pasteurisation and sterilisation. 相似文献
5.
Yanjun Yang Maria Anna Polak Giovanni Cascante 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2010,25(6):736-744
Surface-breaking cracks affect the material and structural properties of concrete pipes. Therefore, the nondestructive evaluation of the crack depth is important to assess the serviceability of these pipes, which are commonly used in underground infrastructure and trenchless installations (micro-tunneling). This paper presents theoretical, numerical and experimental results for the depth evaluation of surface-breaking cracks. The wall of a concrete pipe is represented as a plate in the numerical and the analytical studies. In the experiments, an ultrasonic piezoelectric transmitter is used as a source. The propagation of the ultrasonic pulse is analyzed using the wavelet transform. A newly proposed wavelet transmission coefficient (WTC) is measured using an equal spacing configuration for the crack depth evaluation in concrete pipes and concrete plates. The results from laboratory and in situ tests show good potential for the practical application of the WTC for the depth evaluation of surface-breaking cracks. 相似文献
6.
AG Ziady T Ferkol DV Dawson DH Perlmutter PB Davis 《Canadian Metallurgical Quarterly》1999,274(8):4908-4916
Complexes composed of peptide ligand for the serpin enzyme complex receptor covalently coupled to poly-L-lysine condensed by charge interaction with plasmid DNA direct gene transfer into receptor bearing cells. We compared intensity and duration of reporter gene expression in vitro and in vivo from serpin-enzyme receptor-directed gene transfer complexes prepared with poly-L-lysine of different chain lengths. When substituted with linker and ligand to comparable extents, DNA complexes containing short chain poly-L-lysine were larger and gave higher peak expression but significantly shorter duration of expression than those containing long chain poly-L-lysine. Both peak expression and duration of expression exceeded that observed with Lipofectin. Neither naked DNA nor DNA complexed with unsubstituted polylysine was effective in gene transfer. For in vivo experiments, complexes containing optimal ligand and degree of substitution (based on in vitro data, peptide C105Y, 11 ligands/plasmid DNA molecule) were prepared with either short chain or long chain polylysine and a beta-galactosidase expression plasmid. Following injection into the tail veins of mice, longer chain complexes gave significantly higher expression of reporter gene in lung and spleen that lasted for a significantly longer period of time than the shorter chain complexes. The short chain poly-L-lysine-DNA complexes were larger in diameter, as assessed by electron microscopy or atomic force microscopy, and gave less protection against DNase digestion in vitro than longer chain complexes. Thus, for gene transfer complexes directed at the serpin enzyme complex receptor, longer chain poly-L-lysine gave a much longer duration of expression both in vitro and in vivo. We speculate that this may be due to protection against degradation afforded the plasmid DNA by the tighter compaction produced by long chain poly-L-lysine. 相似文献
7.
8.
Retrospective analysis of the Beijing family of Mycobacterium tuberculosis in preserved lung tissues
L Qian JD Van Embden AG Van Der Zanden EF Weltevreden H Duanmu JT Douglas 《Canadian Metallurgical Quarterly》1999,37(2):471-474
Direct repeat spoligotyping of 85 paraffin-embedded lung biopsies was used to investigated the occurrence around Beijing of the Beijing family of Mycobacterium tuberculosis. Samples ranged in time from 1956 to 1990. Hybridization patterns were found with 49 (58%) samples, and 45 (92%) produced typical Beijing family patterns extending over the 34-year period. 相似文献
9.
Yi-Chun Chen Yii-Der I. Chen Xiaohui Li Wendy Post David Herrington Joseph F. Polak Jerome I. Rotter Kent D. Taylor 《Lipids》2009,44(8):733-743
HMG-CoA reductase (HMGCR) is an enzyme involved in cholesterol synthesis. To investigate the contribution of the HMGCR gene to lipids and lipoprotein subfractions in different ethnicities, we performed an association study in the Multi-Ethnic
Study of Atherosclerosis (MESA). In total, 2,444 MESA subjects [597 African-Americans (AA), 627 Chinese-Americans (CHA), 612
European-Americans (EA), and 608 Hispanic-Americans (HA)] without statin use were included. Participants had measurements
of blood pressure, anthropometry, and fasting blood samples. Subjects were genotyped for 10 single nucleotide polymorphisms
(SNPs). After excluding SNPs with minor allele frequency <5%, a single block was constructed. The most frequent haplotype
was H1 (41–56%) in all ethnic groups except AA (H2a, 44.9%). Lower triglyceride level was associated with the H2a haplotype
in AA and H2 in HA. In HA, H4 carriers had higher levels of triglyceride and small low-density lipoprotein (s-LDL), and lower
high-density lipoprotein cholesterol (HDL-c), while carriers with H7 or H8 had associations with these traits in the opposite
direction. No significant association was discovered in both CHA and EA. The total variation for triglyceride that could be
explained by H2 alone was 2.6% in HA and 1.4% in AA. In conclusion, HMGCR gene variation is associated with multiple lipid/lipoprotein traits, especially with triglyceride, s-LDL, and HDL-c. The
impact of the genetic variance is modest and differs greatly among ethnicities. 相似文献
10.