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白喉毒素类免疫毒素研究进展 总被引:8,自引:0,他引:8
白喉毒素类免疫毒素是将缺失天然受体结合活性的白喉毒素片段或突变体与抗体或细胞因子偶联而得到的一类新型导向药物,它可特异性识别并结合靶细胞,通过发挥其ADP核糖基化活性而抑制细胞蛋白合成,引发细胞凋亡。由于白喉毒素类免疫毒素能高效、特异地杀伤特定靶细胞,而使其在肿瘤等疾病的药物开发中暂露头角。综述了基于白喉毒素的免疫毒素的研制现状与应用前景 。 相似文献
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Bacterial surface layers (S-layers) are cell envelope structures ubiquitously found in gram-negative and gram-positive bacteria, including Lactobacillus. S-layers play a role in the determination and maintenance of cell shape as virulence factors, mediate cell adhesion, and regulate immature dendritic and T cells. In this study, we sought to understand the involvement of MAPK serine/threonine kinases in alterations in Endometrial epithelial cells (ESC) growth induced by Lactobacillus crispatus (L. crispatus) slpA, an S-layer protein. We applied various concentrations of L. crispatus to cultured ESCs and observed growth and changes in the phosphorylation status of ERK1/2, JNK, and p38. Similar experiments were conducted using L. crispatus lacking and overexpressing slpA. We found that ESC growth was altered by slpA primarily via ERK1/2. Our findings suggest that L. crispatus slpA promotes ESC growth mainly through an ERK1/2-dependent pathway. 相似文献
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Permafrost degradation affects soil properties and vegetation, but little is known about its consequent effects on the soil bacterial community. In this study, we analyzed the bacterial community structure of 12 permafrost-affected soil samples from four principal permafrost types, sub-stable permafrost (SSP), transition permafrost (TP), unstable permafrost (UP) and extremely unstable permafrost (EUP), to investigate the effects of vegetation characteristics and soil properties on bacterial community structure during the process of permafrost degradation. Proteobacteria, Acidobacteria, Actinobacteria and Bacteroidetes were the predominant phyla in all four permafrost soil types. The relative abundance of Proteobacteria decreased in the order SSP > TP> UP > EUP, whereas the abundance of Actinobacteria increased in the order SSP < TP < UP < EUP. Moreover, the Actinobacteria/Proteobacteria ratio increased significantly in the order SSP < TP < UP < EUP along with permafrost degradation, which may be useful as a sign of permafrost degradation. Redundancy analysis (RDA) showed that bacterial communities could be clustered by permafrost types. Analysis of single factors revealed that soil moisture (SM) was the most important factor affecting the bacterial community structure and diversity, followed by soil total nitrogen (STN) and vegetation cover (VC). Partial RDA analysis showed that the soil properties and vegetation characteristics jointly shaped the bacterial community structure. Hence, we can conclude that permafrost degradation, caused by global warming, affects vegetation and soil properties and consequently drives changes in the soil bacterial community structure. 相似文献
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Scale-up cultivation enhanced arachidonic acid accumulation by red microalgae Porphyridium purpureum
Chang Jingyu Le Kai Song Xiaoqiang Jiao Kailin Zeng Xianhai Ling Xueping Shi Tuo Tang Xing Sun Yong Lin Lu 《Bioprocess and biosystems engineering》2017,40(12):1763-1773
Bioprocess and Biosystems Engineering - The present study attempts to cultivate Porphyridium purpureum under different scale-up conditions for further development and commercialization of... 相似文献
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Cascade transduction and production of the light-nitric oxide signal from shoots to roots in maize seedlings exposed to enhanced UV-B radiation 总被引:1,自引:0,他引:1
Manxiao?Zhang Guangxiu?Liu Tuo?Chen Lizhe?AnEmail author Xunling?Wang 《Acta Physiologiae Plantarum》2009,31(1):175-185
The biomasses, rate of apparent nitric oxide (NO)-release, nitric oxide synthase (NOS) activity as well as β-d-endo and exo-glucanase activity of the cell wall were analyzed and determined in the roots of maize seedlings. It was found
that rhizospheric treatments of 2-phenyl-4,4,5,5-tetramethlimida-zoline-l-oxyl-3-oxide (PTIO), a NO scavenger, and radiation
of enhanced ultraviolet-B (UV-B) to aerial parts of the seedling markedly inhibited the rate of NO release in roots, raised
the activity of β-d-endo and exo-glucanase, and increased the biomasses of roots. The patent inhibitor, N-nitro-l-arginine (LNNA), of NOS was unable to inhibit NOS activity and NO generation. Inversely, reactive oxygen species (ROS) eliminator,
N-acetyl-cysteine (NAC), stimulated the rate of NO release. There is no relationship between NOS activity and the rate of NO
release. The latter showed a positive correlation with nitrate reductase (NR) activity, whereas it showed a negative correlation
with the bio-masses and the activity of β-d-endo and exo-glucanase. All results implicated that NO was a by-product generated by NR catalysis, whereas NR activity was
sensitively repressed by the systemic signal network (involved in ROS) induced by enhanced UV-B. It indicated that the downstream
signal molecule of enhanced UV-B light is probably ROS which decreased NO generation through inhibiting NR activity. The endogenous
NO generated by NR catalysis is perhaps such a messenger for restraining β-d-endo and exo-glucanase activity that the root growth was retarded. 相似文献
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男性泌尿生殖道支原体感染及药敏分析 总被引:1,自引:0,他引:1
探讨男性尿道炎患者支原体感染率及其敏感性,为临床治疗支原体感染导致的疾病提供合理用药的参考依据。采用海泰生物的史原体分离鉴定试剂盒,取前列腺液或尿道分泌物,对1116份疑为泌尿生殖系统感染的男性患者进行了支原体检测和抗生素敏感性检测。1116份男性患者标本中共分离出274株支原体,242株Uu对美满霉素、强力霉素、环雨沙星、司帕沙星、氧氟沙星、阿齐霉素、罗红霉素、交沙霉素、克拉霉素、壮观霉素的敏感率分别为95.1%、94.6%、17%、70.3%、31.1%、76%、77.7%、92.6%、83.5%、43.8%。30椿Uu+Mh对美满霉素、强力霉素、环丙沙星、司帕沙星、氧氟沙星、阿齐霉素、罗红霉素、交沙霉素、克拉霉素、壮观霉素的敏感率分别为70%、66.7%、20%、40.1%、26.8%、23.4%、23.4%、50%、23.3%、20%。泌尿生殖道支原体的耐药性监测对指导临床治疗具有重要意义,可以根据药敏结果指导临床合理使用抗菌药物。 相似文献
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