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1.
白纹伊蚊在竹林里孳生的阳性比为75.4%;而在竹林包围的居民区阳性比为15.3%。白纹伊蚊在居民区孳生密度布雷图指数为19.4,容器指数为6.2%。居民区孳生蚊虫的主要场所是泡菜坛,泡菜坛主要孳生蚊种是骚扰阿蚊,阳性比为73.7%,其次是淡色库蚊为20.2%,贪食库蚊为14.0%,白纹伊蚊最低,为9.1%。  相似文献   
2.
在竹叶及其提取物中检出了相当含量的一种羟化赖氨酸—δ-OH-Lys,主要以游离单体和小肽的形式存在。从桂竹和金毛竹叶样分别测得其含量占干叶氨基酸总量的1.33%和1.40%,约相当于其中Lys含量的1/4.醇-水提取的过程有富集δ-OH-Lys的作用,其在提取物中的含量远远高于Lys.这一特殊的非蛋白氨基酸以相当含量存在于竹叶中,可能有着特殊的生物学意义。  相似文献   
3.
竹鼠马尔尼菲青霉菌感染的病理学研究   总被引:1,自引:0,他引:1  
目的 研究马尔尼菲青霉菌感染竹鼠的组织病理学方法。方法 应用HE,Grocotte,免疫组化染色及电镜观察。结果 马尔尼菲青霉菌引起竹鼠各脏器的组织病理学改变为化脓性病变及肉芽肿性病变,病变轻微。结论 竹鼠为马尔尼菲青霉菌的天然储库,主要侵犯竹鼠的肺和单核巨噬细胞系统。  相似文献   
4.
High surface area activated carbon fibers (ACF) have been prepared from bamboo by steam activation after liquefaction and curing. The influences of activation temperature on the microstructure, surface area and porosity were investigated. The results showed that ACF from bamboo at 850 °C have the maximum iodine and methylene blue adsorption values. Aside from the graphitic carbon, phenolic and carbonyl groups were the predominant functions on the surface of activated carbon fiber from bamboo. The prepared ACF from bamboo were found to be mainly type I of isotherm, but the mesoporosity presented an increasing trend after 700 °C. The surface area and micropore volume of samples, which were determined by application of the Brunauer-Emmett-Teller (BET) and t-plot methods, were as high as 2024 m2/g and 0.569 cm3/g, respectively. It was also found that the higher activation temperature produced the more ordered microcrystalline structure of ACF from bamboo.  相似文献   
5.
目的:比较鲜竹沥不同炮制品多糖的化学特征,并评估其体外抗氧化活性,为鲜竹沥物质基础研究提供理论依据。方法:分别采用苯酚-硫酸法、改良福林-酚试剂(Lowery)法、高效分子排阻色谱联用蒸发光散射检测器分析法(HPSEC-ELSD)、高效分子排阻色谱联用多角度激光散射与示差折光仪分析法(HPSEC-MALLS-RID)、扫描电子显微镜(SEM)对不同炮制工艺鲜竹沥多糖的化学特征进行多维度比较,采用1,1-二苯基-2-苦基肼基(DPPH)自由基清除能力检测试剂盒评价体外抗氧化活性。结果:干馏、火制和水提鲜竹沥的多糖含量、多糖的糖含量及蛋白含量有明显差异,特别是干馏法鲜竹沥多糖的蛋白含量和HPSEC-ELSD指纹图谱与其他两种炮制品的差异较大;进一步HPSEC-MALLS-RID分析表明,干馏法鲜竹沥多糖色谱峰1的相对分子质量远大于其他炮制品,且相对分子质量分布较其他炮制方法更分散;SEM分析发现,干馏法鲜竹沥多糖的表面及断面较其他炮制品更光滑。体外抗氧化活性检测显示,3种炮制品多糖均有一定的抗氧化活性,其中干馏法鲜竹沥多糖具有最强的抑制活性,水提法次之,火制法最弱。结论:不同炮制工艺不仅影...  相似文献   
6.
患儿,女,4岁。患儿出生即出现全身干燥、红斑、鳞屑,伴渗液。头发、眉毛稀疏,口周皮沟加深,呈放射状,双手、双足可见片状、环状或多环状的红色斑片,其周边有小片灰白色“双边”鳞屑。光镜下见头发呈竹节状改变。血常规中嗜酸粒细胞计数增高,血清IgE增高。诊断:Netherton综合征。给予保湿剂外用。  相似文献   
7.
张锐  徐彭  吴燕红 《中草药》2009,40(12):1856-1858
目的 研究竹根的化学成分.方法 采用色谱方法 分离化学成分,根据波谱数据及理化常数分析进行结构鉴定.结果 分离鉴定了9个化合物,分别为3-(p-羟基苯)-(2,3)环氧-1-丙酸(Ⅰ),2,3-二羟基-1-(4-羟基-3,5-二甲氧基苯基)-1-丙酮(Ⅱ)、(+)-鹅掌揪树脂醇B(Ⅲ)、原儿茶醛(Ⅳ)、原儿茶酸(Ⅴ)、荭草苷(Ⅵ)、牡荆苷(Ⅶ)、异荭草苷(Ⅷ)、异牡荆苷(Ⅸ).结论 化合物Ⅰ为新化合物,命名为环氧香豆酸(epoxy coumaric acid).  相似文献   
8.
Treatment modification to improve the durability of bamboo against biotic and abiotic factors often results in adverse effects to its mechanical properties due to changes in hygroscopic characteristics. This study aims at exploring in more detail, the effect of treatment modification, in particular smoke treatment, on the hygroscopic nature of bamboo. In the first part of this study, changes to its chemical structure were investigated by Raman and Fourier-transform infrared (FTIR) spectroscopic techniques. From Raman analysis, specific bands attributed to lignin component in bamboo, namely at 1600 cm−1 and 1632 cm−1, which varied in intensities among treated and untreated specimens, could be considered to assess the extent of treatment modification. Besides, FTIR results showed that the chemical constituents of bamboo inner and outermost surfaces vary extensively with distinctive changes during treatment modification. The steam component in smoke treatment is assumed to cause a slight increase in the moisture content in the outermost surface of smoked bamboo as evidenced by FTIR results. In addition, the hydrophobic surface of smoked bamboo, which was affected during smoke treatment modification due to superior mean roughness parameter in its outermost surface, impacted its water-repelling ability. From FTIR results, an increase in lignin in bamboo was confirmed at peak 1114 cm−1, which occurred as a result of thermal effect above a temperature of 100 °C leading to poly-condensation reactions. The increase in lignin is assumed to cause an overall increase in hardness of smoked bamboo which was found to be two-fold higher when compared with the untreated ones. The approach of this research investigation, which has shown the benefit of using spectroscopic techniques to monitor and understand the changes in the hygroscopic nature of bamboo surfaces, can likewise be considered to predict the corresponding effects of treatment modification or degradation on the mechanical properties of natural materials.  相似文献   
9.
With the global escalation of the aging process, the research on aging mechanisms and anti-aging strategies has become a hot spot. As the most external organ of the human body, skin can be used as an ideal organ for the study of endogenous and exogenous aging. Bamboo leaf flavonoids (BLF) possess a variety of biological effects such as antioxidant, anti-bacterial, anti-inflammatory, lipid-lowering, anti-radiation, and anti-aging. However, it is still unclear whether they can delay skin aging. This study aimed to analyze the inhibitory effect of BLF on skin aging and explore their molecular mechanisms. We found that 10–40 μg/mL BLF significantly inhibited the senescence of HaCaT cells induced by AAPH, which might be related to their antioxidant and anti-inflammatory abilities. Further mechanism studies showed that mitogen-activated protein kinase (MAPK), especially the p38 MAPK pathway, was the key to BLF to alleviate the senescence of HaCaT cells. In addition, autophagy was also involved in the anti-senescence effect of BLF. The results were also verified in UVB-induced photoaging mice. Therefore, BLF can be used as a potential therapeutic agent to intervene skin aging in vitro and in vivo.  相似文献   
10.
In this study, tripropylene glycol was used as a reducting agent in the polyol process to reduce silver nitrate to the form of silver particles deposited onto the surface of bamboo charcoal (BC). The reduction temperature and time were critical parameters as they control the size of the silver particles formed as well as their distribution onto the surface of the BC. The reduction of silver nitrate by the tripropylene glycol occurred at a temperature of 120 °C for 3 h, and the silver particles, which had a face-centered cubic lattice structure, were distributed onto the surface of the BC. These synthesis conditions should work well with tripropylene glycol as reducing agent that can be helpful in the convenient preparation of Ag/BC particles. When Ag/BC powders were manufactured using 3 g of silver nitrate content, the prepared composites had the largest thermal conductivity at 0.2490 W/(m·K).  相似文献   
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