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排序方式: 共有740条查询结果,搜索用时 46 毫秒
1.
Milena Jankovic Ivana Novakovic Dejan Nikolic Jasmina Mitrovic Maksic Slavko Brankovic Ivana Petronic Dragana Cirovic Sinisa Ducic Mirko Grajic Dragana Bogicevic 《International journal of molecular sciences》2021,22(9)
Diabetic neuropathy (DN), the most common chronic and progressive complication of diabetes mellitus (DM), strongly affects patients’ quality of life. DN could be present as peripheral, autonomous or, clinically also relevant, uremic neuropathy. The etiopathogenesis of DN is multifactorial, and genetic components play a role both in its occurrence and clinical course. A number of gene polymorphisms in candidate genes have been assessed as susceptibility factors for DN, and most of them are linked to mechanisms such as reactive oxygen species production, neurovascular impairments and modified protein glycosylation, as well as immunomodulation and inflammation. Different epigenomic mechanisms such as DNA methylation, histone modifications and non-coding RNA action have been studied in DN, which also underline the importance of “metabolic memory” in DN appearance and progression. In this review, we summarize most of the relevant data in the field of genetics and epigenomics of DN, hoping they will become significant for diagnosis, therapy and prevention of DN. 相似文献
2.
大庆外围盆地侏罗纪-早白垩世早期古气候研究 总被引:2,自引:0,他引:2
为扩大勘探领域,运用古生物资料对大庆外围盆地的古气候进行了研究,外围盆地株罗纪-早白垩世早期发育的地层有早侏罗世海拉尔盆地的东宫组,中侏罗世三江盆地的绥滨断陷的绥滨组,晚侏罗世三江盆地的东荣组,虎林盆地的裴德组,七虎林组,早白垩世早期鸡西盆地,三江盆地的滴道组,城子河组、穆棱组,虎林盆地的下云山组,上云山组,在这些组中除晚株罗世东荣组,裴德组,七虎林组外,其它各组都产有比较丰富的孢粉化石,未发现孢粉化石的层位,依据植物化石,得出早株罗世东营组为潮湿的暖温带气候,中侏罗世绥滨组为潮湿的北亚热带气候,晚侏罗世为潮湿的暖温带气候,早白垩世早期滴道组,下云山组为潮湿的北亚热带气候,城子河组、上云山组为潮湿的中亚热带气候,穆棱组为潮湿的南亚热带气候。 相似文献
3.
大庆长垣外围油田的开发问题 总被引:1,自引:0,他引:1
方凌云 《大庆石油地质与开发》1989,(3)
本文在对大庆长垣外围油田的地质情况、油藏类型综合分析评价的基础上,论述了开发这些油田的一系列有关问题。 相似文献
4.
较为详细地介绍AT91SAM7S64芯片的I2C接口控制器中外围数据控制器(PDC)的使用方式,并将其与AT24C04之间的通信作为实例给出完整的应用开发流程和软硬件详细描述。该方法的可行性已经为工程实践和实际产品所证实。该操作也可推广到其他AT91SAM7S系列ARM处理器与其他I2C接口器件间的通信。并对其他拥有外围数据控制器的接口开发有一定的借鉴意义。 相似文献
5.
主要论述了TMS320F240串行外设接口模块的特点,并通过与MCS5l单片机通信,实现液晶显示。 相似文献
6.
Ming-Yen Hsiao Ya-Wen Wu Wen-Shiang Chen Yu-Ling Lin Po-Ling Kuo Chueh-Hung Wu 《International journal of molecular sciences》2021,22(7)
Entrapment neuropathy (EN) is a prevalent and debilitative condition caused by a complex pathogenesis that involves a chronic compression–edema–ischemia cascade and perineural adhesion that results in excessive shear stress during motion. Despite decades of research, an easily accessible and surgery-free animal model mimicking the mixed etiology is currently lacking, thus limiting our understanding of the disease and the development of effective therapies. In this proof-of-concept study, we used ultrasound-guided perineural injection of a methoxy poly(ethylene glycol)-b-Poly(lactide-co-glycoilide) carboxylic acid (mPEG-PLGA-BOX) hydrogel near the rat’s sciatic nerve to induce EN, as confirmed sonographically, electrophysiologically, and histologically. The nerve that was injected with hydrogel appeared unevenly contoured and swollen proximally with slowed nerve conduction velocities across the injected segments, thus showing the compressive features of EN. Histology showed perineural cellular infiltration, deposition of irregular collagen fibers, and a possible early demyelination process, thus indicating the existence of adhesions. The novel method provides a surgery-free and cost-effective way to establish a small-animal model of EN that has mixed compression and adhesion features, thus facilitating the additional elucidation of the pathophysiology of EN and the search for promising treatments. 相似文献
7.
Goren Saenz-Pipaon Esther Martinez-Aguilar Josune Orbe Arantxa Gonzlez Miqueo Leopoldo Fernandez-Alonso Jose Antonio Paramo Carmen Roncal 《International journal of molecular sciences》2021,22(7)
Peripheral arterial disease (PAD) of the lower extremities is a chronic illness predominantly of atherosclerotic aetiology, associated to traditional cardiovascular (CV) risk factors. It is one of the most prevalent CV conditions worldwide in subjects >65 years, estimated to increase greatly with the aging of the population, becoming a severe socioeconomic problem in the future. The narrowing and thrombotic occlusion of the lower limb arteries impairs the walking function as the disease progresses, increasing the risk of CV events (myocardial infarction and stroke), amputation and death. Despite its poor prognosis, PAD patients are scarcely identified until the disease is advanced, highlighting the need for reliable biomarkers for PAD patient stratification, that might also contribute to define more personalized medical treatments. In this review, we will discuss the usefulness of inflammatory molecules, matrix metalloproteinases (MMPs), and cardiac damage markers, as well as novel components of the liquid biopsy, extracellular vesicles (EVs), and non-coding RNAs for lower limb PAD identification, stratification, and outcome assessment. We will also explore the potential of machine learning methods to build prediction models to refine PAD assessment. In this line, the usefulness of multimarker approaches to evaluate this complex multifactorial disease will be also discussed. 相似文献
8.
Mike Barbeck Marie-Luise Schrder Said Alkildani Ole Jung Ronald E. Unger 《International journal of molecular sciences》2021,22(9)
In addition to their chemical composition various physical properties of synthetic bone substitute materials have been shown to influence their regenerative potential and to influence the expression of cytokines produced by monocytes, the key cell-type responsible for tissue reaction to biomaterials in vivo. In the present study both the regenerative potential and the inflammatory response to five bone substitute materials all based on β-tricalcium phosphate (β-TCP), but which differed in their physical characteristics (i.e., granule size, granule shape and porosity) were analyzed for their effects on monocyte cytokine expression. To determine the effects of the physical characteristics of the different materials, the proliferation of primary human osteoblasts growing on the materials was analyzed. To determine the immunogenic effects of the different materials on human peripheral blood monocytes, cells cultured on the materials were evaluated for the expression of 14 pro- and anti-inflammatory cytokines, i.e., IL-6, IL-10, IL-1β, VEGF, RANTES, IL-12p40, I-CAM, IL-4, V-CAM, TNF-α, GM-CSF, MIP-1α, Il-8 and MCP-1 using a Bio-Plex® Multiplex System. The granular shape of bone substitutes showed a significant influence on the osteoblast proliferation. Moreover, smaller pore sizes, round granular shape and larger granule size increased the expression of GM-CSF, RANTES, IL-10 and IL-12 by monocytes, while polygonal shape and the larger pore sizes increased the expression of V-CAM. The physical characteristics of a bone biomaterial can influence the proliferation rate of osteoblasts and has an influence on the cytokine gene expression of monocytes in vitro. These results indicate that the physical structure of a biomaterial has a significant effect of how cells interact with the material. Thus, specific characteristics of a material may strongly affect the regenerative potential in vivo. 相似文献
9.
提出了一种改进的CIS电子耳蜗的脉冲刺激方案。利用听觉外周模型产生一种符合听神经发放机制的刺激脉冲序列来刺激电极,代替传统的均匀交替刺激方案,不仅可以通过包络而且可以通过脉冲间隔来传递语音信息,确保了语音的空间编码和时间编码。听觉仿真实验表明,相对于其他两种方案,方案可以有效地传递更多更丰富的语音信息,在汉语声调识别实验中至少提高19.2%识别率,在可懂度的对比实验中具有最高可懂度。 相似文献
10.
吕高峰 《浙江水利水电专科学校学报》2014,(3):18-23
面板堆石坝的应力变形,尤其是面板的应力变形及周边缝、垂直缝的变形是工程设计施工人员最为关注的部位.以响水涧抽水蓄能电站上水库主坝为例,建立三维有限元模型,计算分析各工况下坝体、面板的的应力应变以及周边缝、垂直缝的变形,为面板坝设计施工提供参考性意见. 相似文献