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41.
Jonas Hafrén 《Journal of Wood Science》2007,53(2):143-146
Two methods of cytochemical staining using Coomassie dye and Cu+-bicinchoninic acid, respectively, showed that there are proteins in thermomechanical pulp (TMP) of Norway spruce. Protein
isolated from TMP was analyzed for amino acid composition. There was about twice the amount of acidic amino acid material
compared with basic amino acids, and the presence of glucosamine indicated that the isolated polypeptides also contained glycoproteins.
The presence of proteins in ray cells and fiber tracheids in TMP adds to the chemical heterogeneity of the structurally complex
high-yield pulp. 相似文献
42.
INTRoDUCTIoNAnthasbeenusedasmedicineandhealthprotectionproductsfora1ongtime-Theant(PolyrhachisvicinaRoger)ismostincommon.TheyaremainlylivinginGuangxiProvince.Theyareablack,irri-tateacidityanddelicatefragranceinsects.ThereisakindofantinWandaMountain,Daxing'anMountain,andXiaoxing'anMountain.Itisabig(aboutmorethanl-ocmlong),strongandnonpollutioninsect.alotofbigandblackantswerecollectedfromWandaMountain.Itwasappraisedbyantexpertstobeantfami1yandantcategory.ItwasnamedFormicacuniculariaLa… 相似文献
43.
干旱胁迫对白桦实生幼苗叶片蛋白质的影响 总被引:9,自引:0,他引:9
The studies on leave protein of Betula platyphylla seedlings by the methods of SDS-PAGE electrophoresis and dimensional gel electrophoresis was concerned. The result indicated that some new proteins such as 29kD pI4.3, 29kD pI4.2, 14kD pI5.3 and 11.5kD pI5.16 protein point were induced by soil drought stress, and some protein disappeared,for instance four protein between 12.4 - 11.5kD pI5.8 - 6.44 in seedlings leaves of B. platyphylla during soil drought stress. 相似文献
44.
外界生态因子对油茶品质影响的研究 总被引:1,自引:0,他引:1
对21个地区58个油茶物种(或优良品种)进行了含油率、脂肪酸组成、碘值和粗蛋白质等化学品质的分析。通过选取14个不同地区的普通油茶(Camellia oleifera Abel)的品质与19个生态因子进行多元线性逐步回归分析,揭示了不饱和脂肪酸含量与纬度成明显的正相关;种仁蛋白质含量与8、9月份的降雨量呈负相关的趋势。品质之间的相关分析表明:不饱和脂肪酸含量与蛋白质含量存在明显的负相关关系;不同物种之间,其不饱和脂肪酸含量与果实的大小成负相关。 相似文献
45.
HUANG Yong-hong SHI Hui-mian ZHOU Xiao-yan XU Hong LUO Zhi-jun XU Fang-yun 《园艺学报》2015,31(7):1340-1344
Receptor type protein tyrosine phosphatase Q (PTPRQ) is an unusual protein tyrosine phosphatase that has intrinsic dephosphorylating activity for various phosphatidylinositiol and phospho-tyrosine substrates, especially the phosphatidylinositol activity. Recent data show that PTPRQ has an important role in various biological processes and is associated with some diseases. In this article, the structure and function of PTPRQ and the relationship between PTPRQ and diseases were briefly summarized. 相似文献
46.
AIM: To observe the neuritogenic actions of botulinum neurotoxin serotype A heavy chain (BoNT/A HC) on cultured Neuro-2a cells and to investigate the related signaling mechanisms for the effect of BoNT/A HC. METHODS: Neuro-2a cells were treated with different doses of BoNT/A HC (0.01, 0.1, 1 and 10 nmol/L), and then the cells were harvested at 24 h, 48 h and 72 h of BoNT/A HC exposure for detecting the neurite length and the percen-tage of the cells with neuronal processes by immunofluorescence staining. The most efficient dose of BoNT/A HC was chosen for exposure to Neuro-2a cells as the above. Whole cell protein was harvested at different time points for detecting the protein levels of phosphorylated ERK1/2 (p-ERK1/2) and phosphorylated Akt (p-Akt) by Western blot. RESULTS: Low doses of BoNT/A HC stimulated the neurite outgrowth, and increased the percentage of the cells with neurites compared with the negative controls (P<0.05), especially in the group with 1 nmol/L of BoNT/A HC treatment. Meanwhile, the phosphorylation of ERK1/2 and Akt was increased after treated with BoNT/A HC. There was an increasing tendency for the phosphorylation of ERK1/2 after the exposure of the cells to BoNT/A HC. The obvious increase in p-ERK1/2 was seen from 60 min to 5 h with 1 nmol/L of BoNT/A HC treatment (P< 0.05), and the increased protein level of p-Akt was mainly observed at 15 min and 60 min (P<0.05). CONCLUSION: BoNT/A HC stimulates the neuritogenesis. The neuritogenic mechanism of BoNT/A HC on Neuro-2a cells might be realized by activation of the phosphorylation of ERK1/2 and Akt. 相似文献
47.
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
48.
酵母蛋白饲喂泌乳奶牛试验报告 总被引:1,自引:0,他引:1
本试验通过在荷斯坦泌乳牛日粮中添加酵母蛋白部分替代豆粕,研究其对泌乳牛干物质采食量、产奶量、乳成分及身体健康情况的影响,选取400头胎次、产奶量相近的中国荷斯坦泌乳牛分为对照组和试验组各200头,试验组每头牛每天饲喂500g酵母蛋白,通过60d的试验,结果表明试验组和对照组奶牛平均日产奶量差异不显著(P〉0.05),分别为32.54kg/d与32.34kg/d。在产奶量不变的基础上,试验组平均干物质采食量降低1.7kg(DM)/d,产奶效率提高,与对照组相比差异极显著(P〈0.01)。 相似文献
49.
50.
Impacts of chlorpyriphos (2, 4, 6 ppm) on the profiles of antioxidant (catalase) and anaerobic (lactate dehydrogenase) enzymes and other macromolecular contents (DNA, RNA, protein) of various tissues of the freshwater fish, Heteropneustes fossilis were studied. Chlorpyriphos significantly decreased the specific activity of catalase (CAT) and lactate dehydrogenase (LDH) in the brain, liver, gill and skeletal muscle of the fish. The reduction in specific activity might be due to the binding of chlorpyriphos or its metabolites with the enzyme molecules or affecting the synthesis and/or degradation of the enzymes. Like enzymes, the DNA, RNA and protein contents decreased in the brain, liver, gill and skeletal muscle of the fish as a function of increase in chlorpyriphos concentrations (2-6 ppm). The chlorpyriphos-induced reduction in these biochemical constituents might be because of alteration in their turnover (synthesis/degradation) in different tissues. The maximum effects on CAT, LDH, DNA, RNA and protein were obtained in response to 6 ppm chlorpyriphos. The present findings suggest chlorpyriphos concentration related impairment in antioxidative, anaerobic and protein synthesizing capacity of the fish. Therefore, the use of higher concentrations of chlorpyriphos should be avoided to protect the health of economically important freshwater food fish. 相似文献