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Summary It has been suggested that the immune system might figure prominently in the regulation of forelimb regeneration. However, neither the nature of this influence nor the aspect(s) of regeneration influenced are clearly known. The determination of which components of the immune system are indispensable for regeneration would be a logical first step in attempting to address such questions. This investigation, therefore, examined the effects of removing the spleen, a major lymphoid organ in the newt, upon the progress of regeneration. Splenectomies performed concomitantly with or after forelimb amputation failed to alter the time course of regeneration. Splenectomies, but not sham-splenectomies, performed prior to amputation reduced the time required to achieve successive stages of regeneration under some, but not all conditions, i.e., when performed 10–20 days before amputation, during the late fall and winter. Up until 35 days after amputation, no gross morphological distortions were observed as a result of splenectomy. It was concluded that the spleen is not required for regeneration to occur.Portions of this work constitute part of the thesis submitted by M.E. Fini in partial fulfillment of the requirements for the M.S. degree in Biology at Boston College  相似文献   
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A model of the humoral immune response, proposed by Dibrov, Livshits and Volkenstein (1977b), in which the antibody production by a constant target cell population depends on the antigenic stimulation at earlier times, is considered from an analytic standpoint. A method of approximation based on a consideration of the asymptotic limit of large delay in the antibody response is shown to be applicable, and to give results similar to those obtained numerically by the above authors. The relevance of this type of approximation to other systems exhibiting outbreak phenomena is discussed.  相似文献   
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With the world-wide increase of patients with renal failure, the development of functional renal replacement therapies have gained significant interest and novel technologies are rapidly evolving. Currently used renal replacement therapies insufficiently remove accumulating waste products, resulting in the uremic syndrome. A more preferred treatment option is kidney transplantation, but the shortage of donor organs and the increasing number of patients waiting for a transplant warrant the development of novel technologies. The bioartificial kidney (BAK) is such promising biotechnological approach to replace essential renal functions together with the active secretion of waste products. The development of the BAK requires a multidisciplinary approach and evolves at the intersection of regenerative medicine and renal replacement therapy. Here we provide a concise review embracing a compact historical overview of bioartificial kidney development and highlighting the current state-of-the-art, including implementation of living-membranes and the relevance of extracellular matrices. We focus further on the choice of relevant renal epithelial cell lines versus the use of stem cells and co-cultures that need to be implemented in a suitable device. Moreover, the future of the BAK in regenerative nephrology is discussed.  相似文献   
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摘要 目的:基于炎症免疫调节探讨艾拉莫德联合硫酸羟氯喹治疗类风湿关节炎(RA)的疗效及作用机制。方法:选择2021年4月~2023年3月期间武汉科技大学附属天佑医院和武汉市第四医院收治的120例RA患者。根据随机数字表法将患者分为对照组和研究组,每组各为60例。对照组接受硫酸羟氯喹治疗,研究组接受艾拉莫德联合硫酸羟氯喹治疗。对比两组疗效、临床症状缓解时间、炎症因子[肿瘤坏死因子α(TNF-α)、白细胞介素-6(IL-6)、干扰素α(IFN-α)、干扰素-γ(IFN-γ)]、视觉疼痛模拟评分(VAS)和简易健康生活质量评分(SF-36)、免疫因子[T淋巴细胞亚群(CD4+、CD8+、CD4+/CD8+)、免疫球蛋白(Ig)G、IgM、IgA]。同时观察两组用药安全性。结果:与对照组相比,研究组的临床总有效率更高(P<0.05)。研究组的关节疼痛、关节肿胀、关节晨僵缓解时间均短于对照组(P<0.05)。治疗6个月后,两组TNF-α、IL-6、IFN-γ、IFN-α下降,且研究组低于对照组(P<0.05)。治疗6个月后,两组CD8+升高,且研究组高于对照组;CD4+、CD4+/CD8+降低,且研究组低于对照组(P<0.05)。治疗6个月后,两组IgG、IgM、IgA下降,且研究组低于对照组(P<0.05)。治疗6个月后,两组VAS评分下降,且研究组低于对照组;SF-36评分升高,且研究组高于对照组(P<0.05)。两组不良反应发生率组间对比未见差异(P>0.05)。结论:艾拉莫德联合硫酸羟氯喹治疗RA,疗效确切,能缩短临床症状缓解时间,缓解关节疼痛和提高患者生活质量,且用药安全、副作用少,其作用机制可能与调节炎症反应、免疫反应有关。  相似文献   
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摘要 目的:本研究旨在探讨对比分析IPS e.max Press铸瓷高嵌体与普兰梅卡CADCAM系统制作的高嵌体修复后牙牙体缺损的效果。方法:以2021年8月-2022年8月我院诊治的60例(86颗)后牙牙体缺损患者为研究对象,采用随机数字表法将其分为研究组(给予普兰梅卡CADCAM系统制作的高嵌体修复)和对照组(给予IPS e.max Press铸瓷高嵌体修复)各30例,对比两组修复前及修复1年后咀嚼功能、牙龈情况、RANK、CXCL16水平、IL-6、IL-8水平,统计修复结果及美牙效果满意度。结果:(1)修复前,两组咀嚼功能比较无差异(P>0.05);修复1年后,研究组咀嚼功能优于对照组(P<0.05);(2)修复前,两组牙龈指数、菌斑指数评分比较无差异(P>0.05);修复1年后,研究组牙龈指数、菌斑指数评分优于对照组(P<0.05);(3)修复前,两组RANK、CXCL16水平比较无差异(P>0.05);修复1年后,研究组RANK、CXCL16水平低于对照组(P<0.05);(4)修复前,两组IL-6、IL-8水平比较无差异(P>0.05);修复1年后,研究组IL-6、IL-8水平与对照组比较(P>0.05);(5)修复1年后,研究组修复体边缘适合性、修复体邻面解剖形态优于对照组(P<0.05);两组修复体表面及边缘着色、修复体折裂与固位比较,差异不显著(P>0.05);(6)修复1年后,研究组美牙效果满意度优于对照组(P<0.05)。结论:与IPS e.max Press铸瓷高嵌体相比,普兰梅卡CADCAM系统制作的高嵌体修复后牙牙体缺损的效果更佳,能够提高咀嚼功能,改善牙龈指数,提高美牙效果满意度。  相似文献   
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摘要 目的:探讨卡瑞利珠单抗联合化疗对晚期非鳞非小细胞肺癌(NSCLC)患者免疫功能和中性粒细胞与淋巴细胞比值(NLR)、C-反应蛋白与白蛋白比值(CAR)的影响。方法:采用回顾性分析,选取2020年1月到2022年12月期间安徽医科大学第一附属医院北区收治的晚期非鳞NSCLC患者100例,按照治疗方法将患者分为对照组(n=48)和观察组(n=52)。对照组接受注射用培美曲塞二钠联合顺铂注射液或注射用奈达铂化疗,观察组在对照组基础上接受卡瑞利珠单抗治疗。对比两组疗效、免疫功能、肿瘤标志物、NLR、CAR,同时观察两组治疗期间不良反应发生率。结果:与对照组相比,观察组的临床总有效率更高(P<0.05)。治疗4个周期后,与对照组相比,观察组癌胚抗原(CEA)、细胞角蛋白19片段抗原21-1(CYFRA21-1)、糖类抗原125(CA125)、NLR、CAR、CD8+更低,CD3+、CD4+、CD4+/CD8+更高(P<0.05)。两组不良反应发生率对比未见差异(P>0.05)。结论:晚期非鳞NSCLC患者在化疗的基础上结合卡瑞利珠单抗治疗,有助于控制疾病进展,提高临床疗效,降低肿瘤标志物水平,提高免疫功能,降低NLR、CAR。  相似文献   
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COVID-19 is a kind of SARS-CoV-2 viral infectious pneumonia. This research aims to perform a bibliometric analysis of the published studies of vitamins and trace elements in the Scopus database with a special focus on COVID-19 disease. To achieve the goal of the study, network and density visualizations were used to introduce an overall picture of the published literature. Following the bibliometric analysis, we discuss the potential benefits of vitamins and trace elements on immune system function and COVID-19, supporting the discussion with evidence from published clinical studies. The previous studies show that D and A vitamins demonstrated a higher potential benefit, while Selenium, Copper, and Zinc were found to have favorable effects on immune modulation in viral respiratory infections among trace elements. The principles of nutrition from the findings of this research could be useful in preventing and treating COVID-19.  相似文献   
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Circadian rhythms in physiology and behavior are ultimately regulated at the hypothalamic level by the suprachiasmatic nuclei (SCN). This central oscillator transduces photic information to the cellular clocks in the periphery through the autonomic nervous system and the neuroendocrine system. The fact that these two systems have been shown to modulate leukocyte physiology supports the concept that the circadian component is an important aspect of hypothalamic-immune communication. Circadian disruption has been linked to immune dysregulation, and recent reports suggest that several circadian clock genes, in addition to their time-keeping role, are involved in the immune response. In this overview, we summarize the findings demonstrating that Natural Killer (NK) cell function is under circadian control. Special issue article in honor of George Fink.  相似文献   
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