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101.
伯乐树种子不同条件贮藏下前后生理比较 总被引:1,自引:0,他引:1
对3个不同地区(浙江省遂昌县、福建省浦城县和浙江江山市)的伯乐树种子形态指标进行了测定。并分别设置3种贮藏方式(A为室内湿沙环境下贮藏;B为低温(4℃)湿沙下贮藏;C为低温(4℃)封口袋中贮藏),对贮藏前后种子的发芽率、发芽势、含水量等生理指标进行了比较研究。结果表明,浦城县地区较另外二个地区的种子狭长而扁平,且质量较小。经130d的贮藏后,3个地区的种子内淀粉含量显著下降(P〈0.05),含水量、蛋白酶活性、淀粉酶活性、蛋白含量和可溶性糖含量则均显著升高(P〈0.05),从而使休眠得以解除。贮藏后的发芽率和发芽势显著提高(P〈0.05),以湿沙低温下的发芽率和发芽势为最高。 相似文献
102.
Keun Soo Ahn Sung-Tae Hong Yu Na Kang Jung Hyeok Kwon Mi Jeong Kim Tae Jun Park Yong Hoon Kim Tae Jin Lim Koo Jeong Kang 《The Korean journal of parasitology》2012,50(4):357-360
A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''. 相似文献
103.
本文对31例非特异性阴道炎病人和31例正常人阴道微生物群进行定性、定量分析.结果表明,阴道炎病人的阴道乳杆菌的平均浓度明显低于正常人,而肠杆菌科、葡萄球菌、棒状杆菌、类杆菌属、支原体却明显增多,阴道炎病人未发现特异性病原体,菌群失调可能是其发病因素。乳杆菌为阴道正常优势菌,对改善阴道的微环境,防止条件致病菌引起的内源性感染具有重要的生理作用。 相似文献
104.
105.
Lee BH Park SY Kang KB Park RW Kim IS 《Biochemical and biophysical research communications》2002,291(5):1218-1224
Resveratrol (RSVL), an edible polyphenolic stilbene, claims a myriad of cardiovascular benefits. However, the molecular underpinnings of such actions are poorly understood. Currently, in sheep coronary arteries (SCA), RSVL markedly (threefold) enhanced cGMP formation (t(1/2): 6.5 min; EC(50): 3 microM). This response was not abrogated by the phosphodiesterase inhibitor (IBMX, 0.5 mM), but was partly sensitive (20-30%) to either removal of the endothelium, treatment with the nitric oxide synthase-inhibitor (L-NMMA, 10 microM), or with the soluble GC (sGC)-inhibitor (ODQ, 10 microM). In membrane preparations from denuded SCA, either RSVL or the pGC agonist atrial natriuretic peptide (ANP, 0.1-1 microM) activated GC in the particulate, but not in the soluble, membrane fraction. By contrast, the nitric oxide donor, sodium nitroprusside (SNP, 1-10 microM), stimulated GC only in the soluble fraction. Further, pretreatment with RSVL partly desensitized the ANP response, but was additive to that of SNP. In arterial tension studies, RSVL relaxed PGF(2alpha)-precontracted denuded rings in a concentration-dependent manner, a response that was markedly enhanced (approximately 18 fold) in the presence of IBMX. Conversely, precontraction with phorbol ester, which also desensitizes pGC, blunted relaxations to RSVL but not to forskolin or SNP. These findings demonstrate that RSVL increases cGMP in coronary arteries, mostly by activation of pGC. This pathway triggers vasorelaxant responses that remain effective in endothelium-disrupted arteries. 相似文献
106.
9-polylysine protein transduction domain: enhanced penetration efficiency of superoxide dismutase into mammalian cells and skin 总被引:2,自引:0,他引:2
Park J Ryu J Jin LH Bahn JH Kim JA Yoon CS Kim DW Han KH Eum WS Kwon HY Kang TC Won MH Kang JH Cho SW Choi SY 《Molecules and cells》2002,13(2):202-208
Antioxidant enzymes, such as superoxide dismutase (SOD) and catalase (CAT), have been considered to have a beneficial effect against various diseases that are mediated by the reactive oxygen species (ROS). Although a variety of modified recombinant antioxidant enzymes have been generated to protect against oxidative stresses, the lack of their transduction ability into cells resulted in a limited ability to detoxify intracellular ROS. To render the SOD enzyme capable of detoxifying intracellular ROS when added extracellularly, cell-permeable recombinant SOD proteins were generated. A human Cu,Zn-superoxide dismutase (Cu,Zn-SOD) gene was fused with a gene fragment that encodes the 9 amino acids Tat protein transduction domain (RKKRRQRRR) of HIV-1 and lysine rich peptide (KKKKKKKKK) in a bacterial expression vector in order to produce a genetic in-frame Tat-SOD and 9Lys-SOD fusion protein, respectively. The expressed and purified Tat-SOD and 9Lys-SOD fusion proteins can transduce into human fibroblast cells, and they were enzymatically active and stable for 24 h. The cell viability of the fibroblast cells that were treated with paraquat, an intracellular superoxide anion generator, was increased by the transduced Tat-SOD or 9Lys-SOD. The transduction efficacy of 9Lys-SOD was more efficient than that of Tat-SOD. We evaluated the ability of the SOD fusion pmteins to transduce into animal skin. This analysis showed that Tat-SOD and 9Lys-SOD fusion proteins efficiently penetrated into the epidermis as well as the dermis of the subcutaneous layer, when sprayed on mice skin (judged by the immunohistochemistry and specific enzyme activities). The enzymatic activity of the transduced 9Lys-SOD was higher than that of Tat-SOD, indicating that the penetration of 9Lys-SOD was more efficient when put into the skin. These results suggest Tat-SOD and 9Lys-SOD fusion proteins can be used as anti-aging cosmetics, or in protein therapy, for various disorders that are related to this antioxidant enzyme and ROS. 相似文献
107.
108.
天然多糖水凝胶具有良好的生物相容性,然而其力学性能调节幅度小,无法满足组织工程应用巨大的需求。通过纤维增强法,不仅可显著提高天然多糖水凝胶的力学性能,还能调节复合水凝胶的降解性能、促进细胞粘附、增殖与分化行为及其组织沉积。常用的天然多糖组织工程水凝胶的纤维增强方法有物理共混法、化学作用法、静电驱动法与自组装法等。本文综述了纤维增强水凝胶的结构与功能特点,讨论了纤维增强对组织工程水凝胶的意义,以期对纤维增强组织工程水凝胶的发展起到促进作用。 相似文献
109.
结合基因功能分类体系Gene Ontology筛选聚类特征基因 总被引:3,自引:0,他引:3
使用两套基因表达谱数据,按各基因的表达值方差,选择表达变异基因对样本聚类,发现一般使用方差较大的前10%的基因作为特征基因,就可以较好地对疾病样本聚类。对不同的疾病,包含聚类信息的特征基因有不同的分布特点。在此基础上,结合基因功能分类体系(Gene Ontology,GO),进一步筛选聚类的特征基因。通过检验在Gene Ontology中的每个功能类中的表达变异基因是否非随机地聚集,寻找疾病相关功能类,再根据相关功能类中的表达变异基因进行聚类分析。实验结果显示:结合基因功能体系进一步筛选表达变异基因作为聚类特征基因,可以保持或提高聚类准确性,并使得聚类结果具有明确的生物学意义。另外,发现了一些可能和淋巴瘤和白血病相关的基因。 相似文献