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91.
齿龈内阿米巴的致病作用与致病机制的研究   总被引:1,自引:0,他引:1  
在注射免疫抑制剂 1周后的大白鼠龈缘涂抹齿龈内阿米巴 (Emtamoebagingivalis ,E .g .) ,5天后 ,牙龈组织出现溃疡、牙周脓肿形成、脓液查见活E .g .、牙槽骨吸收等牙周炎病症。电镜术与生化分析发现 :E .g .伪足活跃、有丰富的溶酶体 ,所含水解酶与ACP显著较健康组高 (P <0 0 1) ,可使牙周组织溶解与受损。SOD较健康组显著性低 (P <0 0 1) ,MDA显著性增高 (P <0 0 1) ,说明E .g .感染产生较多氧自由基可使细胞膜受损 ,加上口腔共生菌的协同作用使免疫力低下的宿主发生牙周炎。  相似文献   
92.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N o 10, pp. 391–393, October, 1993  相似文献   
93.
BACKGROUND: Blood flow restriction training is a new resistance training. Blood flow restriction training can not only influence muscle strength, mass and physical ability, but also induce and activate related signaling pathways such as neural plasticity and cognitive function. However, current studies have not systematically evaluated the effects of blood flow restriction training on the cognitive ability of different populations, and the neurobiological mechanism by which blood flow restriction training improves cognitive function is not fully understood. Moreover, the application solutions of blood flow restriction training are still not fully understood. OBJECTIVE: To review the existing experimental studies on the influence of blood flow restriction training on cognitive function of different populations, deeply analyze the potential neurobiological mechanisms, and summarize the previous rational programs of blood flow restriction training that improve cognitive function, in order to provide theoretical support and practical guidance for the safe and effective application of this technology. METHODS: PubMed, Web of Science, and CNKI databases were retrieved using “blood flow restriction training, pressure training, blood flow restriction therapy, blood flow restriction, pressure blood block training, blood block, cognitive function, cognitive ability” as Chinese keywords and “blood flow restriction therapy, KAATSU training, KAATSU volume, resistance training, BFR therapy, BFRT, blood flow restriction exercise, cognition, cognitive function” as English keywords. The search deadline was October 2022. Relevant inclusion criteria were established according to the research needs and finally 84 articles were included for further review. RESULTS AND CONCLUSION: The experimental studies regarding the influence of blood flow restriction training on cognitive ability mainly select healthy people as subjects in an attempt to explore its application value in healthy elderly populations. However, in general, there are few studies on elderly people and patients with cognitive dysfunction. Blood flow restriction training can be used as a key factor to trigger positive neural adaptation to a certain extent by applying hypoxic stimulation to the extremity to induce transient brain oxygen deficiency. Blood flow restriction training can significantly improve the levels of bioactive molecules related to the improvement of cognitive function, mainly including insulin-like growth factor 1, growth hormone, vascular endothelial growth factor, brain-derived neurotrophic factor, lactic acid, hypoxia-inducible factor 1α, peroxisome proliferator-activated receptor-γ coactivation factor 1α and norepinephrine. The formulation of blood flow restriction training application programs involves the selection of training participants, the determination of exercise factors and the setting of cuff pressure and its width. Future studies should pay attention to the comparison of the application effects of different blood flow restriction training methods in different populations, so as to make the clinical application of blood flow restriction training more perfect and reasonable, providing more theoretical basis for blood flow restriction training to improve cognitive function in patients with cognitive dysfunction. © 2023, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.  相似文献   
94.
The possibility of involvement of a Na–Ca exchange mechanism in the contractile responses induced by a reduction of external Na concentration ([Na]0) has been studied in isolated guinea-pig aorta. Low-Na (11.9 mM) solution (Lisubstituted) produced a contraction in ouabain-treated muscles in the presence of phentolamine (10–6 M). The magnitude of the contraction was dependent on the duration of the pretreatment with ouabain (2×10–5 M). Ca-free solution, but not verapamil (10–6 M), abolished the contraction induced by low-Na solution. The muscles were loaded with various amounts of Na by incubating the tissue with ouabain and varying [Na]0 (11.9–148.7 mM) in the absence of Ca. The magnitude of the contractions induced in these muscles by low-Na solution containing Ca (2.5 mM) was dependent on the cellular Na content. Loss of cellular Na into low-Na solution followed a single exponential time course and the rate coefficient of Na-loss in the presence of external Ca was about twice as great as in the absence of Ca. Cellular45Ca uptake in low-Na solution was significantly greater in Na-loaded tissues (pretreated with ouabain for 3 h) than in normal tissues. The45Ca uptake in low-Na solution was not inhibited by verapamil. These results suggest that the contraction induced by low-Na solution is caused by a Ca influx which is dependent on internal Na (a Na–Ca exchange mechanism).  相似文献   
95.
TNF inhibits malaria hepatic stages in vitro via synthesis of IL-6   总被引:5,自引:0,他引:5  
We examined the capacity of murine recombinant tumor necrosis factor (rmTNF) to induce an inhibitory effect at the hepatic stage on malaria induced by Plasmodium yoelii sporozoites. When injected three times, 1.0 micrograms of rmTNF was found to protect 78% of mice against a sporozoite challenge. In contrast, whatever the dose and the schedule of administration, no inhibition was observed when purified hepatocyte cultures were infected with P. yoelii. The addition of non-parenchymal hepatic cells to hepatocyte cultures restored the capacity of TNF to modulate hepatic stage development, leading to up to 44% inhibition. Antibodies to interleukin 6 reversed the anti-parasite activity in the co-culture system.  相似文献   
96.
黄倩  张娜  方云 《现代预防医学》2022,(14):2683-2688
目的 探索和构建公共卫生本科生实践能力培养长效机制的模型。方法 查阅文献、问卷调查和访谈以构建模型,通过对照组和干预组统计学分析和开展问卷满意度调查来分析模型的可行性,数据分析采用t检验、秩和检验,统计分析使用Stata 14软件。结果 干预组和对照组实践能力总计分数差异有统计学意义(t = 2.660,P = 0.002),综合实践能力分数差异有统计学意义(t = 6.656,P<0.001)。学生满意度,就业机构或升学学校满意度分析均提示模型能够提升学生的实践能力。结论 模型具有可行性,为进一步提升公共卫生本科生实践能力提供了方法实践。  相似文献   
97.
【目的】 分析国际顶级综合类科技期刊公众传播模式及特点,为我国科技期刊公众传播能力建设提供建议。【方法】 以Altmetric Top 100入选论文数量最多的NatureScience和PNAS三刊为研究对象,剖析其在公众传播产品、媒体传播体系和新闻媒体人才支撑等方面的模式和特征。对照分析我国最有影响力的综合类科技期刊《国家科学评论》和《科学通报》的公众传播特点。【结果】 以《国家科学评论》和《科学通报》为代表的我国综合类科技期刊的公众传播能力提升迅速,但仍存在新闻传媒人才短缺、期刊集约化程度不高、公众传播机制尚未建立等问题。【结论】 我国综合类科技期刊需要着力增强传媒人才培育、集约化品牌发展、公众传播机制建设,以促进我国科技期刊公众传播能力提升。  相似文献   
98.
【目的】 提出期刊出版界、科技界和期刊评价方普遍认同的编委会运行机制优化指标体系,为期刊编委会创建、换届或优化提供参考。【方法】 采用德尔菲法和层次分析法,构建我国科技学术期刊编委会运行机制优化指标体系,并确定权重。【结果】 构建由 “编委会组织优化指标体系(宏观)”和 “编委办刊贡献考核指标体系(微观)”组成的“我国科技学术期刊编委会运行机制优化指标体系”。【结论】 本研究集期刊出版界、科技界和期刊评价方的智慧,构建了“我国科技学术期刊编委会运行机制优化指标体系”,将宏观层面优化和微观层面考核相结合,为我国科技学术期刊编委会创建、换届或优化提供指南或参考,以期真正实现我国科技学术期刊的“专家办刊”,进而推动我国科技学术期刊的高质量发展。  相似文献   
99.
胚胎植入是生殖过程中最关键的步骤之一,植入失败的胚胎无法继续发育,是导致不孕的重要原因之一。胚胎植入的成功依赖于子宫内膜的高容受性和具有植入能力的胚胎。自噬是细胞质、细胞器和内含物被双膜囊泡吸收并运输到溶酶体进行降解和再循环的过程,是一种维持内环境稳态的方式。大量证据表明,自噬在胚胎植入的各个环节有着重要的作用。基于此探讨了自噬与子宫内膜容受性和胚胎植入能力的关系,并根据最新的研究进展,梳理了大黄素、梓醇、芍药苷、白藜芦醇、叶酸、玉米赤霉烯酮、姜黄素、汉黄芩素、槲皮素、白杨素、小檗碱、芹菜素、菲西汀、山柰酚在内的14种中药单体调控自噬干预胚胎植入的不同环节的5个机制,包括促进子宫内膜基质细胞蜕膜化、促进细胞凋亡、调节激素水平、协调炎症、促进排卵,希望对今后中药单体提高胚胎植入的成功率提供参考及思路。  相似文献   
100.
2型糖尿病(T2DM)是一种以胰岛素抵抗、高胰岛素血症、糖脂代谢紊乱为特征,临床以血糖升高为主要表现的慢性代谢性系统疾病。其病因及发病机制复杂,目前尚无完全治愈的手段,严重威胁着人类的健康,给社会和家庭带来了沉重的负担。皂苷是一类结构比较复杂的苷类化合物,具有来源广、安全性高、不良反应低等优点。中药皂苷作为中药重要的活性成分,具有降血糖、降血脂、抗炎、抗氧化、抗肿瘤、调节免疫等多种生物活性。近年来,众多研究表明中药皂苷类成分可有效地防治糖尿病。虽然中药皂苷类成分降糖作用及机制研究众多,但目前尚缺乏对中药皂苷类成分治疗T2DM作用及机制研究的系统综述。故该文围绕中药皂苷类成分改善胰岛β细胞功能、改善胰岛素抵抗、抑制糖苷酶活性、降低炎症反应、抗氧化应激、调节肠道菌群等降糖机制进行系统归纳,并分析目前研究存在的问题及发展趋势,以期为深入研究中药皂苷类成分的降糖作用提供理论基础,为药物的开发与临床应用提供科学依据。  相似文献   
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