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131.
132.
Myocardial infarction still remains the main cause of death in western countries, despite considerable progress in the stent development area in the last decades. For clarification of the underlying mechanisms and the development of new therapeutic strategies, the availability of valid animal models are mandatory. Since we need new insights into pathomechanisms of cardiovascular diseases under in vivo conditions to combat myocardial infarction, the validity of the animal model is a crucial aspect. However, protection of animals are highly relevant in this context. Therefore, we establish a minimally invasive and simple model of myocardial infarction in mice, which assures a high reproducibility and survival rate of animals. Thus, this models fulfils the requirements of the 3R principle (Replacement, Refinement and Reduction) for animal experiments and assure the scientific information needed for further developing of therapeutical strategies for cardiovascular diseases.  相似文献   
133.
Fragment QRS (fQRS) complex is a myocardial conduction abnormality that indicates myocardial scar. It is defined as additional notches in the QRS complex. Though initially fQRS was defined in the setting of normal QRS duration (<120 m s), later it has been expanded to include conditions with wide QRS complexes as in bundle branch block, ventricular ectopy and paced rhythm, when more than 2 notches are present. It is an important, yet often overlooked marker of mortality and arrhythmic events in many cardiac diseases. The significance of fQRS lies in the fact that it just requires a surface ECG for its recording and the value of information about the condition of the heart it dispenses based on the clinical setting. We review the role of fQRS in predicting adverse cardiac events in various conditions.  相似文献   
134.
Poor recovery of neuronal functions is one of the most common healthcare challenges for patients with different types of brain injuries and/or neurodegenerative diseases. Therapeutic interventions face two major challenges: (1) How to generate neurons de novo to replenish the neuronal loss caused by injuries or neurodegeneration (restorative neurogenesis) and (2) How to prevent or limit the secondary tissue damage caused by long-term accumulation of glial cells, including microglia, at injury site (glial scar). In contrast to mammals, zebrafish have extensive regenerative capacity in numerous vital organs, including the brain, thus making them a valuable model to improve the existing therapeutic approaches for human brain repair. In response to injuries to the central nervous system (CNS), zebrafish have developed specific mechanisms to promote the recovery of the lost tissue architecture and functionality of the damaged CNS. These mechanisms include the activation of a restorative neurogenic program in a specific set of glial cells (ependymoglia) and the resolution of both the glial scar and inflammation, thus enabling proper neuronal specification and survival. In this review, we discuss the cellular and molecular mechanisms underlying the regenerative ability in the adult zebrafish brain and conclude with the potential applicability of these mechanisms in repair of the mammalian CNS.  相似文献   
135.
Growing evidence indicates that the melanocortin 1 receptor (MC1R) and its ligand α–melanocyte-stimulating hormone (α-MSH) have other functions in the skin in addition to pigment production. Activation of the MC1R/α-MSH signaling pathway has been implicated in the regulation of both inflammation and extracellular matrix homeostasis. However, little is known about the role of MC1R/α-MSH signaling in the regulation of inflammatory and fibroproliferative responses to cutaneous injury. Although MC1R and α-MSH localization has been described in uninjured skin, their spatial and temporal expression during cutaneous wound repair has not been investigated. In this study, the authors report the localization of MC1R and α-MSH in murine cutaneous wounds, human acute burns, and hypertrophic scars. During murine wound repair, MC1R and α-MSH were detected in inflammatory cells and suprabasal keratinocytes at the leading edge of the migrating epithelial tongue. MC1R and α-MSH protein levels were upregulated in human burn wounds and hypertrophic scars compared to uninjured human skin, where receptor and ligand were absent. In burn wounds and hypertrophic scars, MC1R and α-MSH localized to epidermal keratinocytes and dermal fibroblasts. This spatiotemporal localization of MC1R and α-MSH in cutaneous wounds warrants future investigation into the role of MC1R/α-MSH signaling in the inflammatory and fibroproliferative responses to cutaneous injury. This article contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.  相似文献   
136.
目的:探讨CO_2点阵激光联合湿润烧伤膏治疗创伤性瘢痕的临床疗效。方法:选取73例创伤性瘢痕患者,年龄21-35岁,对照组(35例)给予CO_2点阵激光术治疗,术后涂抹莫匹罗星软膏护理,观察组(38例)采用CO_2点阵激光术联合湿润烧伤膏治疗。通过对患者治疗后3个月的体征、疗效及3个月内不良反应的发生情况评价CO_2点阵激光术联合湿润烧伤膏对创伤性瘢痕的疗效。结果:与治疗前相比,两组治疗后3个月的VSS评分均明显提高(P0.05),但两组间VSS评分相比差异没有统计学意义(P0.05)。治疗后3个月,观察组的治疗有效率明显高于对照组(P0.05),治疗后3个月期间,观察组的不良反应发生率明显低于对照组(P0.05),色素沉积和创面感染是主要的不良反应症状。结论:CO_2点阵激光技术联合润湿烧伤膏对于创伤性瘢痕具有良好的治疗效果,且安全性高。  相似文献   
137.
目的:探讨剖宫产瘢痕妊娠(CSP)患者经子宫动脉栓塞术(UAE)后并发下肢深静脉血栓(DVT)的临床病例的诊断治疗要点。方法:回顾性分析2014年-2016年我院收治的剖宫产瘢痕妊娠患者经子宫动脉栓塞术后并发下肢深静脉血栓(DVT)5例患者的临床特点及诊断、治疗方法。结果:2014年-2016年,我院CSP患者经UAE治疗后发生DVT的发病率为1.63%,患者平均年龄35.2岁。DVT临床症状出现于UAE术后3-6天,多表现为下肢的疼痛及酸胀,深静脉血栓均出现在介入穿刺处肢体。用彩色多普勒血流显像诊断深静脉血栓安全可靠。采用低分子肝素皮下注射抗凝治疗均取得较好效果。结论:剖宫产瘢痕妊娠患者经子宫动脉栓塞术治疗后有发生下肢深静脉血栓风险,DVT发生与穿刺处肢体制动,血管受压,血液回流障碍有关。手术前后应采取预防措施,低分子肝素钠抗凝对DVT治疗有效。  相似文献   
138.
The Menispermaceae family contains ca. 72 genera with 450 species that are almost entirely tropical. Its phylogeny at the tribal level has never been examined using molecular data. Here we used DNA sequences of the chloroplast matK gene and trnL-F regions, and the nuclear ITS region to study the delimitation and position of the tribe Menispermeae within the family and its subtribal monophyletic groups. Family-wide phylogenetic analyses of the chloroplast data produced two strongly supported clades. The first clade contains two subclades: Coscinieae including Arcangelisia and Anamirta, and Tinosporeae sensu lato including Fibraureae, supported by morphological characters, such as traits of the cotyledon, stylar scar and embryo. The second clade consists of the tribes Menispermeae sensu DC. and Tiliacoreae Miers. All our analyses surprisingly recognized that tribe Menispermeae is not monophyletic unless tribe Tiliacoreae is included, suggesting that characters of cotyledon and stylar scar are very important for the infrafamilial classification, and that endosperm presence vs. absence was over-emphasized in traditionally tribal division of the family. Our topologies indicate a secondary loss of endosperm. The monophyly of two subtribes of the tribe Menispermeae, Stephaniinae and Cissampelinae, is supported by the cpDNA and ITS data, as well as by morphological characters, including aperture types and shapes, and colpal membrane features of pollen grains, and sepal number of male flowers. The Cocculinae was recognized as a paraphyletic group containing the remaining genera of the tribe Menispermeae.  相似文献   
139.
The heterogeneity of savanna ecosystems is guaranteed by disturbance events like fires, droughts, floods and browsing and grazing by herbivores. For conservation areas with limited space to preserve biodiversity, fire monitoring is crucial. Long periods of satellite remotely sensed data provide an alternative solution to estimate the distribution of different vegetation types and fire-affected patches over time. This study focusses on the application of MODIS data to detect, identify and delineate fire-affected areas in Kruger National Park (KNP), South Africa, for the period 2001–2003. Fire scars on KNP’s savanna were identified using threshold and supervised classification methods on moderate-resolution imaging spectroradiometer (MODIS) with 500-m resolution and 32-day global composites using a combination of band 1 (red), 2 (NIR, near infrared), 4 (green) and 6 (SWIR, short wave infrared). On identified fire scars, the spectral indexes of albedo, normalised difference infrared index (NDII) and normalised difference vegetation index (NDVI) were extracted. The following four broad habitat types were used for this analysis: riparian woodland, dense woodland, mixed woodland and open-tree savanna. The values of albedo, NDII and NDVI during the dry season (June to October) for different years are lower on fire-affected patches. Mixed woodland is the largest habitat burned with 21%, 43% and 2% of the KNP area affected by fire in 2001, 2002 and 2003, respectively. Riparian woodland is the least affected by fire. The supervised classification method has a greater accuracy for fire scars detection in KNP savannas during the dry season. We conclude that MODIS data can be used successfully for fire monitoring in savanna ecosystems.  相似文献   
140.
目的:探讨可调脉宽倍频Nd:YAG激光对兔耳增生性瘢痕的治疗作用.方法:制作兔耳增生性瘢痕模型,术后30天对兔耳增生性瘢痕进行可调脉宽倍频Nd:YAG激光干预,观察兔耳瘢痕大体形态和组织病理改变,并采用免疫组化的方法检测兔耳瘢痕治疗前后血管内皮生长因子(vascular endothelial growth factor,VEGF)的表达情况.结果:可调脉宽倍频Nd:YAG激光干预后,兔耳增生性瘢痕出现明显的萎缩,免疫组化检查VEGF表达减弱.结论:可调脉宽倍频Nd:YAG激光可能通过损伤瘢痕组织内的微血管促进兔耳增生性瘢痕萎缩,对早期增生性瘢痕具有治疗作用.  相似文献   
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