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971.
本试验利用蛭石作为扦插茶梅的基质,研究了营养液、插条叶面积、光与温度对插条切口愈合与发根的影响。结果表明,利用营养液扦插,有利于插条根的分化与生长,这与矿质元素促进碳水化合物的合成与提供适合的pH环境有关.插条的叶面积大小与发根存在密切的正相关。当气温在25℃左右的不同处理时,对插条切口的愈合与愈伤组织的形成,影响不明显。气温在25—30℃范围内,温度高一些,有利于根的形成,从而提高生根率与根数;气温超过30℃,根的形成速率降低,而根仍能继续生长。光强为自然太阳光强的20%以内,较高的光强对根的分化与生长均是有利的。  相似文献   
972.
Inhibition of fructose absorption may suppress adiposity and adiposity-related diseases caused by fructose ingestion. Eucalyptus leaf extract (ELE) inhibits intestinal fructose absorption (but not glucose absorption); however, its active compound has not yet been identified. Therefore, we evaluated the inhibitory activity of ELE obtained from Eucalyptus globulus using an intestinal fructose permeation assay with the human intestinal epithelial cell line Caco-2. The luminal sides of a cell monolayer model cultured on membrane filters were exposed to fructose with or without the ELE. Cellular fructose permeation was evaluated by measuring the fructose concentration in the medium on the basolateral side. ELE inhibited 65% of fructose absorption at a final concentration of 1 mg/mL. Oenothein B isolated from the ELE strongly inhibited fructose absorption; the inhibition rate was 63% at a final concentration of 5 μg/mL. Oenothein B did not affect glucose absorption. In contrast, the other major constituents (i.e., gallic acid and ellagic acid) showed little fructose-inhibitory activity. To our knowledge, this is the first report that oenothein B in ELE strongly inhibits fructose absorption in vitro. ELE containing oenothein B can prevent and ameliorate obesity and other diseases caused by dietary fructose consumption.  相似文献   
973.
Carica papaya (papaya) leaf extract has been used for a long time in a traditional medicine to treat fever in some infectious diseases such as dengue, malaria, and chikungunya. The development of science and technology has subsequently made it possible to provide evidence that this plant is not only beneficial as an informal medication, but also that it has scientifically proven pharmacological and toxicological activities, which have led to its formal usage in professional health care systems. The development of formulations for use in nutraceuticals and cosmeceuticals has caused this product to be more valuable nowadays. The use of good manufacturing practice (GMP) standards, along with the ease of registering this product facilitated by policies of the national government, will absolutely increase the value of papaya leaf extract as a vital nutraceutical and cosmeceutical products in the near future. In this article, we review the potential of papaya leaf extract to be a high-value commodity in terms of its health effects as well as its industrial benefits.  相似文献   
974.
以2010年红塔集团在云南4个烟叶生产基地内收集的中部上等烟叶样品为试验对象,其中玉溪、楚雄、昭通的烤烟品种为K326,大理的烤烟品种为红大,共计烟叶近红外光谱1 276条;应用光谱特征投影及相关分析等方法对不同烤烟生产基地之间烟叶近红外光谱的分析结果表明:将样品随机按2:1划分为分析集与验证集后,其分析集与验证集的一维、二维投影均值的相关系数都达到0.99以上,具有较好的一致性;同时,应用一种相似度计算方法得到了不同基地的烟叶样品光谱之间的相似度值,该相似度值可为烟叶的种植规划、质量管理以及烟草工业企业的原料收购和烟叶配方等提供参考。  相似文献   
975.
光谱指数的植被叶片含水量反演   总被引:1,自引:0,他引:1  
利用光谱技术监测植被水分状况是了解植被生理状况及生长趋势的重要手段之一。选择艾比湖湿地自然保护区作为靶区。采用聚类分析、变量投影重要性分析(VIP)以及敏感性分析等方法,对植被不同含水量进行分级,并针对不同等级的植被含水量进行估算及验证。结果表明: (1)基于聚类分析中的欧氏距离的方法将植被叶片相对含水量划分为高等、中等、低等三个等级,其范围分别为70.76%~80.69%,53.27%~70.76%,31.00%~53.27%。在中红外与远红外(1 350~2 500 nm)之间,反射率越低植被含水量越高;波长380~1 350 nm范围,无此现象。(2)应用VIP方法可知,所选的8种植被水分指数VIP值均超过了0.8,说明植被水分指数预测能力均较强且差别不显著。其中MSI,GVMI与植被叶片相对含水量的非线性三次拟合函数效果最佳,MSI决定系数R2为0.6575和GVMI决定系数R2为0.674 2。植被叶片相对含水量在30%~45%范围,MSI指数的NE值最低,在45%~90%范围时,GVMI指数的NE值最低。NDWI1240指数的NE值在70%左右起伏较大,说明NDWI1240 指数在植被含水量为70%左右,预测能力较差。(3)通过误差分析可知GVMI指数反演的结果误差最小,不同的植被指数对不同含水量的植被估算结果相差较为明显,因此分段估算植被含水量是有必要的。综上所述,利用高光谱遥感技术对监测艾比湖保护区植被生长及干旱环境提供基础研究。  相似文献   
976.
In this work, bionic-superhydrophobic surfaces on aluminum alloy 5083 are fabricated by reciprocatingtype high-speed wire cut electrical discharge machining based on the hydrophobic property of the rice leaf. Submillimeter-scale rectangular grooves are processed on the surfaces. The superhydrophobic surface has shown a static contact angle of 158°, which is similar to the rice leaf. The morphological features are characterized by scanning electron microscopy, showing that the craters and bumps are uniformly distributed on the surfaces of the rectangular grooves with porous nanostructures. The method proposed in this work has the advantages of using only one step,requiring no further procedure to lower the surface energy and processing a large-area surface efficiently.  相似文献   
977.
Perilla leaves contain many interfering substances; thus, it is difficult to protect the analytes during identification and integration. Furthermore, increasing the amount of sample to lower the detection limit worsens the situation. To overcome this problem, we established a new method using a combination of solid‐phase extraction and dispersive solid‐phase extraction to analyze pyraclostrobin in perilla leaves by liquid chromatography with ultraviolet absorbance detection. The target compound was quantitated by external calibration with a good determination coefficient (R2 = 0.997). The method was validated (in triplicate) with three fortification levels, and 79.06– 89.10% of the target compound was recovered with a relative standard deviation <4. The limits of detection and quantification were 0.0033 and 0.01 mg/kg, respectively. The method was successfully applied to field samples collected from two different areas at Gwangju and Muan. The decline in the resiudue concentrations was best ascribed to a first‐order kinetic model with half‐lives of 5.7 and 4.6 days. The variation between the patterns was attributed to humidity. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
978.
对粳稻"嘉花1号"经~(60)Coγ诱变处理获得的稳定遗传低温敏感叶色突变体tcm11(thermo-sensitive chloroplast mutant 11)进行了表型鉴定与遗传分析.在20℃条件下,该突变体三叶期之前幼苗均表现为黄色,光合色素含量明显下降,叶绿体发育不完整,从第4叶开始逐渐转为浅黄绿色直至最后死亡.而在32℃条件下,其表型与野生型相比没有明显差异,具有低温敏感属性.通过对培矮64S与tcm11杂交的F_2代分离群体进行遗传分析,发现该低温敏感突变体性状是受单个隐性核基因(tcm11)控制,利用图位克隆技术对tcm11进行定位,将其定位在第11号染色体的InDel分子标记ID13252与SSR分子标记MM1361之间一个约1 566 kb的区域内.这也为后续的研究奠定了基础.  相似文献   
979.
铬是植物的非必需元素,对植物的生长发育具有显著的抑制作用.采用双向电泳和质谱技术,研究了铬胁迫对西红花叶片蛋白表达的影响.通过质谱技术,成功鉴定出9个在铬胁迫后下调表达的蛋白,分别为细胞分裂循环蛋白48、ATP合成酶α亚基、核酮糖二磷酸羧化酶长链(2个)、未知蛋白、核酮糖二磷酸羧化加氧酶、蛋白酶体α亚基、铁蛋白和蛋白酶体β亚基;6个上调表达的蛋白,分别为蔗糖合酶、真核起始因子4A、α-1,4-葡聚糖蛋白合成酶、1-氨基环丙烷-1-羧酸氧化酶、异黄酮还原酶类似物IRL和未知蛋白.以上结果为研究植物响应铬胁迫的分子机制提供了参考.  相似文献   
980.
Volumetric elastic modulus (VEM) is an important parameter in biophysics and biomechanics of plants for in particular understanding cell growth. This paper proposes a new relation that can be used for precisely determining VEM. With the aid of this relation, it shows that the exponential approximation of the pressure-volume relationship adopted in most of the literatures in this field may lead to serious errors on VEM.  相似文献   
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