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排序方式: 共有1806条查询结果,搜索用时 15 毫秒
21.
Zhen Lu Angelica Ortiz Ioannis I. Verginadis Amy R. Peck Farima Zahedi Christina Cho Pengfei Yu Rachel M. DeRita Hongru Zhang Ryan Kubanoff Yunguang Sun Andrew T. Yaspan Elise Krespan Daniel P. Beiting Enrico Radaelli Sandra W. Ryeom J. Alan Diehl Hallgeir Rui Constantinos Koumenis Serge Y. Fuchs 《The Journal of clinical investigation》2021,131(10)
Intercellular biomolecule transfer (ICBT) between malignant and benign cells is a major driver of tumor growth, resistance to anticancer therapies, and therapy-triggered metastatic disease. Here we characterized cholesterol 25-hydroxylase (CH25H) as a key genetic suppressor of ICBT between malignant and endothelial cells (ECs) and of ICBT-driven angiopoietin-2–dependent activation of ECs, stimulation of intratumoral angiogenesis, and tumor growth. Human CH25H was downregulated in the ECs from patients with colorectal cancer and the low levels of stromal CH25H were associated with a poor disease outcome. Knockout of endothelial CH25H stimulated angiogenesis and tumor growth in mice. Pharmacologic inhibition of ICBT by reserpine compensated for CH25H loss, elicited angiostatic effects (alone or combined with sunitinib), augmented the therapeutic effect of radio-/chemotherapy, and prevented metastatic disease induced by these regimens. We propose inhibiting ICBT to improve the overall efficacy of anticancer therapies and limit their prometastatic side effects. 相似文献
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A. Marijke Keestra Marcel R. de ZoeteLieneke I. Bouwman Mahdi M. VaeziradJos P.M. van Putten 《Developmental and comparative immunology》2013
Toll-like receptors (TLRs) are a major class of innate immune pattern recognition receptors that have a key role in immune homeostasis and the defense against infections. The research explosion that followed the discovery of TLRs more than a decade ago has boosted fundamental knowledge on the function of the immune system and the resistance against disease, providing a rational for clinical modulation of the immune response. In addition, the conserved nature of the ancient TLR system throughout the animal kingdom has enabled a comparative biology approach to understand the evolution, structural architecture, and function of TLRs. In the present review we focus on TLR biology in the avian species, and, especially, on the unique functional properties of the chicken TLR repertoire. 相似文献
23.
Omar K. Khalique Mahdi Veillet-Chowdhury Andrew D. Choi Gudrun Feuchtner Juan Lopez-Mattei 《Journal of Cardiovascular Computed Tomography》2021,15(4):304-312
Increasing data have accumulated on the role of Cardiac Computed Tomography (CCT) in infective endocarditis (IE) with high accuracy for large vegetations, perivalvular complications and for exclusion of coronary artery disease to avoid invasive angiography. CCT can further help to clarify the etiology of infective prosthetic valve dysfunction (e.g. malposition, abscess, leak, vegetation or mass). Structural interventions have increased the relevance of CCT in valvular heart disease and have amplified its use. CCT may be ideally integrated into a multimodality approach that incorporates a central role of transesophageal echocardiography (TEE) with 18-FDG PET and/or cardiac magnetic resonance in individually selected cases, guided by the Heart Team. The coronavirus-19 (COVID-19) pandemic has resulted in renewed attention to CCT as a safe alternative or adjunct to TEE in selected patients. This review article provides a comprehensive, contemporary review on CCT in IE to include scan optimization, characteristics of common IE findings on CCT, published data on the diagnostic accuracy of CCT, multimodality imaging comparison, limitations and future technical advancements. 相似文献
24.
Reza Barati rashvanlou Abbas Rezaee Mahdi Farzadkia Mitra Gholami Majid Kermani 《RSC advances》2020,10(59):35718
Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. 相似文献
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S. J. Aldavood R. Zahedi I. Sohrabi Haghdoost M. Rezaie Kanooy A. Veshkini 《Comparative clinical pathology》2013,22(4):585-589
Ocular ultrasonography is a valid and non-invasive diagnostic method used to evaluate ocular and retrobulbar structures, especially when opacity of the anterior segments precludes ophthalmic examination of deeper structures of the eye or when exophthalmos is present. This study describes the B-mode ultrasonographic findings of the globe in 10 rabbits with experimental glaucoma. Ultrasonography of the eyes, using Titan TM machine and 7 MHz linear array transducer, was performed transpalpebrally. Ocular ultrasonographic findings revealed two cases of increased corneal thickness, seven cases of change in the anterior chamber depth, one case of increased echogenicity in the anterior chamber, three cases of retinal detachment, one case of increased iris and ciliary body thickness and six cases of change in axial globe length. Increased echogenicity of the capsule, cortex and nucleus was found in two cases. Six cases showed change in lens diameter. Increased echogenicity and altered lens diameter are typical of cataract. Two cases of point-like lesions, mass and/or linear echodensities in mild extent were observed within the vitreous representing haemorrhage, vitreous degeneration or detachment. The B-mode ultrasonographic imaging technique has become an essential diagnostic tool in most ocular disease. This method provides additional information allowing the clinician to offer more accurate diagnosis, treatment and prognosis in glaucoma. 相似文献
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While trauma registries provide the mechanisms to collect comprehensive, timely and accurate data related to the injuries and evaluate trauma care systems, they have not been established in most developing countries. On the other hand, in complex projects that have large aims, a logical framework approach (LFA) can help summarize and describe the multiple branches of the project systematically, and elucidate the main goals, extensive objectives, activities and expected outcomes. Therefore a LFA can be used to design and guide trauma registry project management, to integrate the cultural, clinical and capacity variations among countries; and to ensure early alignment of the project's design and evaluation. 相似文献
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