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991.
【目的】探索光质对‘红地球’葡萄果实品质的影响。【方法】以‘红地球’葡萄为试验材料,转熟时对果穗进行红、橙、绿、蓝、白滤光膜与避光套袋处理,测定分析了转熟至采收期间套袋对果实单果质量、糖酸积累、着色与花色素苷合成等品质特征的影响。【结果】研究表明蓝色滤光膜套袋‘红地球’葡萄果实中可溶性固形物与总糖含量增加,葡萄糖、果糖、蔗糖3种糖分含量相比白膜分别提高了7.2%、13.7%、17.2%,糖酸比提高,显著促进了花色素苷的合成,色度角h最小,果皮中主要花色素苷组分芍药素-3-O-葡萄糖苷和矢车菊素-3-O-葡萄糖苷较白膜显著增加,分别提高18.4%与12.5%,PAL活性增强,促进了葡萄积累花色素苷;而避光处理的‘红地球’果实糖酸比小,花色素苷合成显著受到抑制。【结论】在我国南方湿热地区果实部位光环境对设施葡萄品质具有重要作用,蓝色滤光膜套袋可以增加蓝紫光的比例,调控葡萄光合产物分配,诱导苯丙氨酸解氨酶(PAL)活性,促进欧亚种‘红地球’葡萄果实糖的积累和着色,改善品质。 相似文献
992.
LIU Lian YU Rong-jie DAI Yun ZENG Zhi-xing GUO Xiao-ling JI Qing-shan ZHONG Jing-xiang 《园艺学报》2015,31(1):135-140
AIM: To construct the prokaryotic expression system containing protein transduction domain (PTD) with heat shock protein 27 (HSP27) in order to prepare and purify the recombinant protein, and to verify whether the recombinant protein PTD-HSP27 has the ability to penetrate the human lens epithelial cell (HLEC) membrane and the rabbit cornea. METHODS: The plasmid pKYB-PTD-HSPB1-6His was constructed by the technique of overlap extension PCR. The plasmid was transformed and PTD-HSP27 was purified through nickel affinity chromatography column and identified by Western blotting. PTD-HSP27-6His was labeled with the fluorescein isothiocyanate (FITC). The penetrating ability of PTD-HSP27 into HLECs and rabbit cornea was tested. RESULTS: The recombinant PTD-HSP27 plasmid was successfully cloned and effectively expressed. The correctness of the recombinant protein PTD-HSP27 was demonstrated. Fluorescence microscopic examination showed that PTD-HSP27-FITC was internalized by HLECs. Fluorescent labeled PTD-HSP27 was then observed in the rabbit aqueous humor. CONCLUSION: The recombined gene PTD-HSPB1 was constructed by overlap extension PCR technique and the PTD-HSP27 fusion protein was prepared and purified by nickel affinity chromatography column. Using the technique of PTD-fusion protein, HSP27 was transduced into HLECs and passed through the cornea. 相似文献
993.
994.
AIM: To investigate the protective effect of pinacidil postconditioning on rat myocardium suffering ischemia/reperfusion injury by mitochondrial proteomics. METHODS: Langendorff apparatus was used to establish the model of myocardial ischemia/reperfusion injury. Sprague-Dawley rats were randomly divided into 2 groups: pinacidil postconditioning group (Pina group) and ischemia/reperfusion injury group (I/R group). After 20 min of perfusion with K-H solution, the perfusion was suspended for 40-min (global ischemia) follow by 60 min of reperfusion in I/R group. In Pina group at the end of 40 min global ischemia, the isolated hearts were perfused with K-H solution containing pinacidil (50 μmol/L) for 2 min followed 58-min perfusion with regular K-H solution. Total proteins extracted from the mitochondria were applied to the two-dimensional gel electrophoresis (2-DE). The differentially expressed protein spots over 2 times were evaluated by a software. Then they were subjected to in-gel digestion, and analyzed by spectrometry. RESULTS: The expression levels of NDUFA10, NDUFS2 and NDUFV2 were elevated but those of IDHA and ECH1 were decreased in Pina group compared with I/R group. Interestingly, 2 spots in the 2-DE map were identified as ATPase subunit δ. The expression levels of one spot was elevated, while the other was decreased. CONCLUSION: Pinacidil postconditioning may decrease the degree of increased expression levels of NDUFA10, NDUFS2 and NDUFV2, promote the expression of IDHA and ECH1, and induce the phosphorylation of ATPase subunit δ, which may be related to the protective mechanism of pinacidil postconditioning. 相似文献
995.
996.
‘乐亭白黄瓜’是河北乐亭县日光温室越冬茬旱黄瓜基地主栽的农家品种,由于缺乏系统选育,品种性状混杂,制约了当地旱黄瓜产业健康发展。现以‘乐亭白黄瓜’为试材,在春季日光温室栽培条件下,对该原始群体的生长势、早熟性、产量和品质等性状进行了调查分析。结果表明:‘乐亭白黄瓜’栽培群体的植株分枝少,但株高和节间长度分离较严重,变异系数分别为33.7%和20.9%。第一雌花节位集中分布在第4~11节;20节内雌花节位数集中分布在2~4个,变异系数27.4%。初步鉴定单性结实力较弱。商品瓜棒状,瓜长度集中分布在20~25cm,变异系数15.1%;瓜皮色均匀一致的占25.7%。雌花花柄长度变异系数为45.0%。该研究结果为黄瓜新品种选育提供参考依据。 相似文献
997.
998.
In this paper, the Artificial Neural Network (ANN) is applied to the internal force analysis of structure. After introducing the model and algorithm of back-propagation network, a trained BP network of three layers is used to calculate the maximum of elastic moment of middle span of two-way slab. In order to enhance the generalized capability of network, the modified value of weight should be regarded as convergence standard and in order to accelerate the learning process without vibration, the method of adding momentum coefficient is adopted. The analysis program of BP network is carried out with the software of Matlab. The result demonstrates that application of ANN in structure analysis is feasible. 相似文献
999.
The relationship between abrasive concentration, length of oscillating chamber, standoff distance and cutting depth, erosion rate as well as cutting specific energy was investigated by experiments in the submerge and surface conditions. The cutting and erosion capabilities of the pre-mixed abrasive water jet and the pulsed abrasive water jet were analyzed in contrast. It is shown that the maximum cutting depth and erosion rate of the pulsed abrasive water jet are respectively 1.67,1.72 and 1.39, 1.47 than the pre-mixed abrasive water jet in submerge and surface conditions. These results attained from the research are useful to increase the cutting efficiency, decrease the energy ratio and expand the application domains of the abrasive water jet. 相似文献
1000.