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Defects of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein affect the homeostasis of chloride, bicarbonate, sodium, and water in the airway surface liquid, influencing the mucus composition and viscosity, which induces a severe condition of infection and inflammation along the whole life of CF patients. The introduction of CFTR modulators, novel drugs directly intervening to rescue the function of CFTR protein, opens a new era of experimental research. The review summarizes the most recent advancements to understand the characteristics of the infective and inflammatory pathology of CF lungs. 相似文献
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减毒沙门菌对实体瘤具有广谱的肿瘤靶向特异性,其可通过激活机体抗肿瘤免疫应答改善肿瘤免疫微环境,从而抑 制肿瘤的发展;高度的肿瘤靶向特异性使得减毒沙门菌可作为理想的抗癌药物与影像探针的表达和递送载体,实现肿瘤诊疗一 体化。减毒沙门菌在基础或临床领域已有着广泛的研究与应用,展现了良好的应用前景,未来可期。对减毒沙门菌的抗肿瘤机 制、应用现状及目前所存在的问题展开分析,探讨如何通过遗传工程技术对减毒菌的安全性、靶向性和抗癌效果等方面进行提 升,将促进减毒沙门菌的转化应用,实现免疫学、生物技术等多学科的交叉融合,有望为临床肿瘤生物治疗提供新的研究方向。 相似文献
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《Dental materials》2022,38(12):2062-2072
ObjectivesTo investigate the effect of a protective coating on the surface characteristics, flexural properties, cytotoxicity, and microbial adhesion of vat-photopolymerization additive-manufacturing denture base polymers.MethodsThe specimens were additively manufactured using digital light processing (DLP). Specimen surfaces were coated with the same printed resin, and mechanical polishing was used for comparison. Surface topography, arithmetical mean height (Sa), and water contact angle values were measured. Furthermore, flexural strength (FS)/modulus and fractography were evaluated. Also, cytotoxicity was evaluated by an extract test. Finally, an adhesion test was used to investigate the adhesion of mixed oral bacteria to the specimens.ResultsThe Sa values in the polished (0.26 ± 0.08 µm) and coated (0.38 ± 0.14 µm) groups were significantly lower than in the untreated (2.21 ± 0.42 µm) and control (2.01 ± 0.37 µm) groups. The coating treatment resulted in a higher FS compared to the untreated surface (p = 0.0002). After the coating treatment, no significant differences were found in relative cell viability between the groups (p > 0.05). The quantitative results showed significantly higher bacterial adhesion in the untreated group than in the polished (p = 0.0047) and coated (p < 0.0001) groups.SignificanceThe surface characteristics and flexural properties were optimized by the protective coating. Also, the protective coating did not adversely affect cytocompatibility. Moreover, the coating treatment could effectively decrease oral bacteria adhering to the surfaces. Therefore, the protective coating treatment can be a less time-consuming alternative to mechanical polishing as a post-processing procedure for the digital denture. 相似文献
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Tsai-Wen Wan Lee-Jene Teng Tatsuo Yamamoto 《Journal of microbiology, immunology, and infection》2021,54(3):527-530
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) threatens human health. A local CA-MRSA with ST8/SCCmecIVl (CA-MRSA/J) has emerged in Japan, being associated with progression from bullous impetigo to potentially fatal invasive infection. We found that CA-MRSA/J has unique bacterial surface structures, spikes, spikes with a cap, and long spikes, reflecting clinical origins. 相似文献
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《Clinical neurophysiology》2021,132(4):967-974
ObjectiveChronic fatigue syndrome (CFS) and fibromyalgia (FM) are disorders of unknown etiology and unclear pathophysiology, with overlapping symptoms of – especially muscular –fatigue and pain. Studies have shown increased muscle fiber conduction velocity (CV) in the non-painful muscles of FM patients. We investigated whether CFS patients also show CV abnormalities.MethodsFemales with CFS (n = 25), with FM (n = 22), and healthy controls (n = 21) underwent surface electromyography of the biceps brachii, loaded up to 20% of maximum strength, during short static contractions. The mean CV and motor unit potential (MUP) velocities with their statistical distribution were measured.ResultsThe CV changes with force differed between CFS-group and both FM-group and controls (P = 0.01). The CV of the CFS-group increased excessively with force (P < 0.001), whereas that of the controls increased only slightly and non-significantly, and that of the FM-group did not increase at all. In the CFS-group, the number of MUPs conveying very high conduction velocities increased abundantly with force and the MUPs narrowed.ConclusionOur results suggest disturbed muscle membrane function in CFS patients, in their motor units involved in low force generation. Central neural deregulation may contribute to this disturbance.SignificanceThese findings help to detangle the underlying mechanisms of CFS. 相似文献
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Evaluation of Dosimetric Effect of Millennium and High Definition Multi Leaf Collimator Using 6 MV Photon Beams 下载免费PDF全文
Aswathi Raj D KhannaHridya VT Sathish PadmanabhanP Mohandass 《Asian Pacific journal of cancer prevention》2021,22(12):3883-3888
Purpose: The present study aims to compare different dosimetric parameters from field sizes defined by secondary and tertiary collimators. A comparison has been drawn between two types of Multi Leaf Collimator (MLC) designs. Materials and Methods: The measurements were obtained using Millennium MLC (Mi-MLC) from Varian Unique™ linear accelerator (LINAC-1) and compared with measurements from Varian Truebeam™ linear accelerator (LINAC-2) using High Definition MLC (HD-MLC). Dosimetric analysis included percentage depth dose (PDD), cross profile, dosimetric leaf gap (DLG) and scatter factor (SF) that were taken for different field sizes defined by both the MLC design and jaw. For beam data measurement PTW Radiation field analyse (RFA) was utilized. Results: When the surface dose for MLC field for linac 1 and linac 2 were compared with jaws they were found to be on the higher side that is 2.8% to 4.9% and 2.2% to 3.6% respectively. The SF was found to vary from -3.2% to 0.73% for LINAC-1 with Mi-MLC when compared with jaws. Similarly, the SF variation from -2.4% to 1.1% was observed for LINAC-2 with HD-MLC as compared with jaw. Larger field sizes gave increased SF while smaller field sizes showed the opposite for HD-MLC. The penumbra was found to be less in HD-MLC as compared to Mi-MLC. Similarly, DLG was found to reduce by 0.056 mm in Mi-MLC when compared with HD-MLC. The results of symmetry and flatness were seen within the limits for both MLC designs. Conclusion: It can be concluded from the results that both the MLC designs have merits and demerits that are based on their effectiveness and clinical use. However, higher surface dose was found in HD-MLC in contrast to Mi-MLC. 相似文献
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ObjectiveOpen injuries of the Tendoachilles present a challenge to the treating surgeon. Although, common in our setting, there is a paucity of literature regarding management of the same. The purpose of this retrospective study was to analyse the functional outcomes following debridement and primary repair of open tears of the Tendoachilles.Materials and methodsPatients with open tears of the tendoachilles, between January 2012 to January 2017. After obtaining demographic data, including mechanism of injury, all patients were managed by adequate debridement and primary repair, by Pennington’s modification of Kessler’s technique in a single sitting, paratenon closed circumferentially, plantaris reinforcement used when end to end repair couldn’t be achieved. Below knee cast for 2 months. Weight bearing started at three months. Statistical analysis using paired t-test for calf circumference, ankle range of motion comparing with uninjured limb. Functional outcome assessment by AOFAS hindfoot score and Achilles tendon rupture score.Results23 male patients, mean age 35, were analysed. Field injury was the most common mechanism, with slip in Indian lavatory pans accounting for four patients. Average time to surgery from injury was 22 hours. Plantaris reinforcement in one case. No case of wound dehiscence, scar adherence, tendon rerupture or infection. One patient had serous discharge at three weeks which settled with oral antibiotics. 21 patients performed single heel raise. There was no significant difference in calf circumference and ankle range of motion compared to uninjured limb. Mean AOFAS score was 92, mean Achilles tendon rupture score 77.ConclusionThough open injuries of the tendoachilles is fraught with complications, early debridement, adequate repair of the tendon edges with circumferential closure of the paratenon, yields adequate functional outcomes with minimal complications. 相似文献