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31.
目的探讨清得佳凝胶治疗烧伤创面的效果及其意义。方法采用家兔皮肤创伤模型,将每只家兔的背部烧伤区域用2种不同颜色的记号笔分成二组:A组(n=9):为实验组(6个部位):常规方法清洁、消毒创口,使用清得佳凝胶涂抹;B组(n=9):为对照组(6个部位):使用常规的无菌敷料覆盖包扎创口。实验于第3、5、7、9天分别取各组皮肤组织进行切片,作组织病理学及免疫组织化学观察。结果1.HE观察结果:烧伤后第3天,A组与B组皮肤烧伤创面结构变化不明显;烧伤后第5天,A组表皮细胞变性坏死程度减轻,成纤维细胞增生,水肿减轻,而B组表皮细胞变性坏死减轻程度不明显,结缔组织胶原纤维变性坏死程度没有得到明显的改善;烧伤后第7天,A组表皮细胞生长良好,真皮组织水肿基本消失;而B组表皮细胞变性坏死程度开始出现减轻,可见部分上皮增生;烧伤后第9天,A组上皮及结缔组织结构基本接近正常,创面愈合情况较好。而B组以上结构出现改变,但愈合状况不是很理想,真皮组织轻、中度水肿,有少量的炎性细胞浸润。2.转化生长因子β1(transforming growth factor β1,TGF-β1)的表达:烧伤后第3天和第5天,A组成纤维细胞胞浆中可见一些棕黄色颗粒,TGF-β1表达较强;B组成纤维细胞胞浆中未见或少见棕黄色颗粒,TGF-β1无表达或表达很弱。烧伤后第7天和第9天,A组成纤维细胞胞浆中可见密集分布的棕黄色颗粒,TGF-β1表达强;B组成纤维细胞胞浆中可见少量的棕黄色颗粒,TGF-β1表达弱。结论清得佳凝胶是一种烧伤创面良好的外用药,能清除创面坏死组织,有利于烧伤创面愈合。  相似文献   
32.
曾义  喻良  王曦  赵戈  黄忠 《现代生物医学进展》2019,19(20):3939-3942
目的:探讨急性缺血性脑卒中(AIS)患者血清半乳糖凝集素3(GAL3)、血清趋化因子12(CXCL12)水平与病情严重程度和预后的关系。方法:选取成都市第五人民医院于2016年2月~2018年9月期间接收的AIS患者138例为观察组,另选取同期来该院行健康体检的志愿者60例为对照组。其中观察组根据美国国立卫生研究所中风量表(NIHSS)评分分为轻症组(n=42,4分),中症组(n=61,4~15分),重症组(n=35,15分),根据改良RABKIN量表(m RS)评分分为预后良好组(n=82)和预后不良组(n=56)。比较对照组、观察组的血清GAL3、CXCL12水平,分析不同NIHSS得分、不同预后的血清GAL3、CXCL12水平,采用Pearson相关性分析血清GAL3、CXCL12水平与NIHSS评分、m RS评分的相关性。结果:观察组血清GAL3、CXCL12水平均显著高于对照组,差异有统计学意义(P0.05)。重症组、中症组AIS患者血清GAL3、CXCL12水平高于轻症组,且重症组高于中症组,差异有统计学意义(P0.05)。预后不良组的AIS患者血清GAL3、CXCL12水平均高于预后良好组,差异有统计学意义(P0.05)。Pearson相关性分析结果可知,血清GAL3、CXCL12水平与NIHSS评分、m RS评分均呈正相关(P0.05)。结论:AIS患者的血清GAL3、CXCL12水平均异常升高,且其升高程度与AIS患者病情严重程度及预后息息相关。  相似文献   
33.
N-(2-吡啶基)-N'-苯基脲(2PU),属苯基脲衍生物,具有细胞分裂素活性,有关其合成和应用的研究未见报道。作者合成了2PU并进行了生物效应试验研究。结果表明,2PU对作物种子萌发时胚根、胚芽的生长具有明显的促进作用,其根、芽生长与2PU浓度之间的关系符合Y=a+bX+eX2+的数学模型。2PU对小麦根芽和赤豆根芽生长最佳浓度分别是0.001~0.0lppm、0.005~0.05ppm,对黄豆根生长以0.001~0.06ppm最佳。  相似文献   
34.
Progesterone (P4) can participate in the development of female mammalian antral follicles through nuclear receptor (PGR). In this experiment, the differences of P4 synthesis and PGR expression in different developmental stages of sheep antral follicles (large > 5mm, medium 2-5mm, small < 2mm) were detected by enzyme-linked immunosorbent assay, immunohistochemistry, qRT-PCR and Western blotting. Secondly, sheep follicular granulosa cells were cultured in vitro. The effects of different concentrations of FSH and LH on P4 synthesis and PGR expression were studied. The results showed that acute steroid regulatory protein (StAR), cholesterol side chain lyase (P450scc) and 3β Hydroxysteroid dehydrogenase (3β-HSD) and PGR were expressed in antral follicles, and with the development of antral follicles in sheep, StAR, P450scc and the expression of 3β-HSD and PGR increased significantly. In vitro experiments showed that FSH and LH alone or together treatment could regulate P4 secretion and PGR expression in sheep follicular granulosa cells to varying degrees, hint P4 and PGR by FSH and LH, and LH was the main factor. Our results supplement the effects of FSH and LH on the regulation of P4 synthesis during follicular development, which provides new data for further study of steroid synthesis and function in follicular development.  相似文献   
35.
Inflammatory response plays an important role in ischaemia reperfusion injury (IRI) through a variety of inflammatory cells. Apart from neutrophils, macrophages and lymphocytes, the role of dendritic cells (DCs) in IRI has been noticed. The study was aimed at investigating whether the high‐mobility group protein box‐1/toll like receptor 4 (HMGB1/TLR4) signalling pathway regulate the migration, adhesion and aggregation of DCs to the myocardium, induce DCs activation and maturation, stimulate the expression of surface costimulatory molecules and participate in myocardial IRI. In vivo, migration, adhesion, and aggregation of DCs was enhanced; the expression of peripheral blood DCs CD80 and CD86, myocardial adhesion molecules were increased; and the infarct size was increased during myocardial ischaemia reperfusion injury myocardial ischemic/reperfusion injury (MI/RI). These responses induced by MI/RI were significantly inhibited by HMGB1 specific neutralizing antibody treatment. Cellular experiments confirmed that HMGB1 promoted the release of inflammatory cytokines through TLR4/MyD88/NF‐κB, upregulated CD80 and CD86 expression, mediated the damage of cardiomyocytes and accelerated the apoptosis. Our results indicate that DCs activation and maturation, stimulate the expression of surface costimulatory molecules by promoting the release of inflammatory factors through NF‐κB pathway and participate in myocardial IRI.  相似文献   
36.
37.
Beta-amyloid (Aβ) derived from amyloid precursor protein (APP) has been associated with retinal degeneration in Alzheimer’s disease (AD) and glaucoma. This study examined whether hypoxia exposure induces Aβ accumulation in RGC-5 cells. While levels of APP mRNA and protein significantly increased in the cells, elevated abundance of Aβ was also observed in cells and culture medium between 12 or 24 and 48 h after 5% O2 hypoxia treatment. Additionally, there is a close relationship between induction of APP and Aβ and intracellular accumulation of ROS along with loss of mitochondrial membrane potential followed by the death of RGC-5 cells in culture under hypoxia. These results suggest a possible involvement of APP and Aβ in the death of RGCs challenged by hypoxia.  相似文献   
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39.
N 6‐methyladenosine (m6A) is a chemical modification present in multiple RNA species and is most abundant in mRNAs. Studies on m6A reveal its comprehensive roles in almost every aspect of mRNA metabolism, as well as in a variety of physiological processes. Although some recent discoveries indicate that m6A can affect the life cycles of numerous viruses as well as the cellular antiviral immune response, the roles of m6A modification in type I interferon (IFN‐I) signaling are still largely unknown. Here, we reveal that WT1‐associated protein (WTAP), one of the m6A “writers”, is degraded via the ubiquitination‐proteasome pathway upon activation of IFN‐I signaling. With the degradation of WTAP, the m6A levels of IFN‐regulatory factor 3 (IRF3) and interferon alpha/beta receptor subunit 1 (IFNAR1) mRNAs are reduced, leading to translational suppression of IRF3 and instability of IFNAR1 mRNA. Thus, the WTAP‐IRF3/IFNAR1 axis may serve as negative feedback pathway to fine‐tune the activation of IFN‐I signaling, which highlights the roles of m6A in the antiviral response by dictating the fate of mRNAs associated with IFN‐I signaling.  相似文献   
40.
杨革  徐承水 《菌物学报》2000,19(3):366-370
利用含亚麻子油的斜面培养基连续传代和逐渐降低培养温度,诱导筛选的方法,从大量丝状真菌中选育到一株产二十碳五烯酸(all-cis-5、8、11、14、17-eicosopnthenoicacid)较高的被孢霉菌(Motierellasp.)SM481。研究得到最适培养基及最适培养条件。在最适培养及产二十碳五烯酸条件下,细胞干重和二十碳五烯酸产量分别为28.8g/L和0.127g/L。  相似文献   
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