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991.
992.
Antimicrobial peptides (AMP) are highly diverse and dynamic molecules that are expressed by specific intestinal epithelial cells, Paneth cells, as well as immune cells in the gastrointestinal (GI) tract. They play critical roles in maintaining tolerance to gut microbiota and protecting against enteric infections. Given that disruptions in tolerance to commensal microbiota and loss of barrier function play major roles in the pathogenesis of inflammatory bowel disease (IBD) and converge on the function of AMP, the significance of AMP as potential biomarkers and novel therapeutic targets in IBD have been increasingly recognized in recent years. In this frontier article, we discuss the function and mechanisms of AMP in the GI tract, examine the interaction of AMP with the gut microbiome, explore the role of AMP in the pathogenesis of IBD, and review translational applications of AMP in patients with IBD.  相似文献   
993.
FRA3B at 3p14.2 is the most active of the common fragile sites in the human genome and is expressed when cells are exposed to the DNA replication inhibitor, aphidicolin. Several lines of evidence suggest that fragile sites are regions of late replication. To elucidate the relationship between the timing of replication across the FRA3B region and its corresponding fragility, we labeled cells with 5-bromo-2'- deoxyuridine (BrdU) and adopted an immunofluorescent procedure to visualize late replicating DNA (BrdU-substituted DNA) in metaphase chromosomes. We also chose 21 markers along the FRA3B region and analyzed the timing of replication using BrdU-labeled DNA from different stages of the cell cycle sorted by flow cytometry. Our results show that there are two distinct alleles that replicate at different stages in the cell cycle and that breaks/gaps preferentially occurred on the chromosome 3 with the late replication allele. These results provide direct evidence that allele-specific late replication is involved in the fragility of the most active common fragile site, FRA3B.   相似文献   
994.
The mRNA vaccine Comirnaty and the inactivated vaccine CoronaVac are both available in Hong Kong’s COVID-19 vaccination programme. We observed waning antibody levels in 850 fully vaccinated (at least 14 days passed after second dose) blood donors using ELISA and surrogate virus neutralisation test. The Comirnaty-vaccinated group’s (n = 593) antibody levels remained over the ELISA and sVNT positive cut-offs within the first 6 months. The CoronaVac-vaccinated group’s (n = 257) median antibody levels began to fall below the cut-offs 4 months after vaccination.  相似文献   
995.
左半结肠癌梗阻外科治疗   总被引:9,自引:0,他引:9  
左半结肠癌梗阻是常见的急腹症,手术治疗方式有多种[1-3],本文简要综述可切除的左半结肠癌梗阻外科治疗方式,着重介绍了支架技术临床应用情况.1左半结肠癌梗阻的手术治疗1.1盲肠造口术(cecostomy)盲肠造口安全简单,可在局麻下进行,一般应用于急...  相似文献   
996.
997.
Ultrasound-guided surgical cholecystostomy with local infiltration anesthesia was combined with radiologic removal of gallstones in 36 elderly patients with acute calculous gallbladder disease who were considered to be at high risk due to multiple coexisting diseases. At cholecystostomy, the fundus of the gallbladder was sutured to the anterior abdominal wall resulting in a short surgical track to the gallbladder. This permitted early percutaneous stone removal through the cholecystostomy track under fluoroscopic guidance. All gallstones were removed in 31 of 36 patients, for an overall success rate of 86%. The success rate was 97% for gallbladder stones, 86% for cystic duct stones, and 63% for common bile duct stones that were removed by traversing the cystic duct. The treatment in the five patients in whom radiologic stone removal was incomplete or unsuccessful consisted of elective cholecystectomy in three, with common bile duct exploration in two of these; endoscopic sphincterotomy and stone extraction in one; and expectant management in one. There were no deaths or serious complications. This technique has thus proved safe and effective in these 36 high-risk patients.  相似文献   
998.
999.
Enhancing the capabilities of the dismounted combatant has been an enduring goal of international military research communities. Emerging developments in exoskeleton technology offers the potential to augment the dismounted combatant’s capabilities. However, the ability to determine the value proposition of an exoskeleton in a military context is difficult due to the variety of methods and metrics used to evaluate previous devices. The aim of this paper was to present a standard framework for the evaluation and assessment of exoskeletons for use in the military. A structured and systematic methodology was developed from the end-user perspective and progresses from controlled laboratory conditions (Stage A), to simulated movements specific to the dismounted combatant (Stage B), and real-world military specific tasks (Stage C). A standard set of objective and subjective metrics were described to ensure a holistic assessment on the human response to wearing the exoskeleton and the device’s mechanical performance during each stage. A standardised methodology will ensure further advancement of exoskeleton technology and support improved international collaboration across research and industry groups. In doing so, this better enables international military groups to evaluate a system’s potential, with the hope of accelerating the maturity and ultimately the fielding of devices to augment the dismounted close combatant and small team capability.  相似文献   
1000.
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