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91.
为对鼠源细胞进行鉴别检测,以鼠线粒体16S rRNA基因序列为靶位点设计特异性引物及探针,建立实时荧光定量PCR检测方法,并评价该方法的特异性及敏感性。结果显示,所建立的检测方法特异性好,针对鼠源细胞基因组荧光定量PCR扩增曲线良好,其他物种来源细胞基因组及生物制品原辅材料未出现特异性扩增曲线;敏感性高,基因拷贝数检出限度为45.3拷贝。本试验建立的荧光定量PCR检测方法能够有效地对鼠源细胞进行快速检测,为细胞质量控制提供了有效方法。 相似文献
92.
XIANG Li-jun WANG Bo-chu DUAN Chuan-ren LIU Liu WANG Qing-hongnistry of Education College of Bioengineering Chongqing University Chongqing Chin 《保鲜与加工》2004,(10):71-74
The paper researches on the degradation of LAS (Linear Alkyl benzene Sulphonate) by combining AS1.860 immobilized with low intensity ultrasonic irradiation. The paper also discusses the influence of pH, rotary velocity, LAS concentration and the condition of low intensity ultrasonic irradiation on the degradation of LAS, the degradation rate of LAS is the main index of our experiment, the results of orthogonal test shows that low ultrasonic irradiation can increase the metabolizing of microorganism cells and facilitate the biodegradation of immobilized cells to LAS, here we research the degradation condition of 50mg/L LAS simulation wastewater with low ultrasonic irradiation, and the results show that the influence is obvious, the optimization degradation rate is about 83%, nine point five percent higher than that of the immobilized cells without ultrasonic irradiation. 相似文献
93.
内毒素对肠黏膜微血管内皮细胞内分泌一氧化氮和内皮素的影响 总被引:1,自引:1,他引:1
目的是研究内毒素(lipopolysaccharide; LPS)导致肠黏膜微血管内皮细胞损伤的作用机制。将所培养的肠黏膜微血管内皮细胞分为空白对照组和LPS组,每组按时间分为4个亚组:3h、6h、9h、12h。空白对照组加维持培养液,LPS组加1μg/ml LPS培养液,在CO2培养箱内静置培养。结果表明,一氧化氮(NO)分泌明显升高,3h后达到高峰,随后逐渐降低,而内皮素(endothelin; ET)分泌急剧升高,9h后达到高峰,随后又开始逐渐降低,但一直保持在较高的水平。所以引起了NO和ET的升高可能是LPS导致肠黏膜微血管内皮细胞的损伤机制。 相似文献
94.
AIM To investigate the effects of 17β-estradiol (E2) treatment on the mesenteric lymphatic microcirculation and isolated lymphatic contractility in rats after hemorrhagic shock, and to explore the relationship between contractility and the difference between intra- and extracellular calcium ion concentrations ([Ca2+]) of lymphatic smooth muscle cells (LSMCs). METHODS Male Wistar rats were divided into sham group, shock group and shock+E2 group. The rats were subjected to hemorrhage [(40±2) mmHg for 90 min] and resuscitation with or without subcutaneous injection of E2 (2 mg/kg). After resuscitation for 3 h, the mesenteric lymphatic microcirculation in vivo was observed. Moreover, the isolated mesenteric microlymphatic rings were prepared for the observations of lymphatic contractility evaluated by the indexes including end-systolic diameter, end-diastolic diameter, contraction frequency (CF) and passive diameter. Meanwhile, the difference between intra- and extracellular [Ca2+] of LSMCs was recorded during lymphatic contraction. RESULTS Treatment with E2 significantly enhanced the CF, total contractile fraction and lymphatic dynamics index in vivo in the rats after hemorrhagic shock, and increased the CF, the fractional pump flow and the difference between intra- and extracellular [Ca2+] of LSMCs in isolated lymphatics from the shocked rats (P <0.05). CONCLUSION Estrogen treatment enhances lymphatic contractility in rats after hemorrhagic shock, which is related to enhancement of difference between intra- and extracellular [Ca2+] of LSMCs. 相似文献
95.
96.
Mast cells are important cells for the innate immunity that reside in tissues including adipose tissue and are involved in various physiological and pathological processes by producing a range of biological mediators. Adipose tissue not only acts as an energy depot and regulator of energy homeostasis that can deposit excess energy and dissipate energy through heat, but also is an active endocrine organ capable of producing hormones and adipokines. The dysfunction of adipose tissue is highly correlated with metabolic disorders, such as obesity, type 2 diabetes mellitus and so on. This review focuses on the physiological and pathological roles of mast cells in adipose tissue. 相似文献
97.
AIM To construct the mouse embryonic stem cell (ESC) line with stable pancreatic and duodenal homeobox 1 (Pdx1 ) expression by Tet-On system, which may lay a foundation for further research on the differentiation of Pdx1+ definitive endoderm cells into pancreatic cells. METHODS The Pdx1 -overexpressing lentiviral vector with green fluorescent protein marker and puromycin resistance was constructed by Tet-On system and was used to infect the mouse ESC. The cells were divided into 3 groups: blank control group (ESC group), empty lentivirus control group (PDX1- ESC group) and Pdx1 lentivirus transfection group (PDX1+ ESC group). Flow cytometry was used to detect the transfected cells after screening by doxycycline (DOX). The function of Tet-On system and the expression of Pdx1 gene were detected. The transfected cells in PDX1- ESC group and PDX1+ ESC group were sorted by flow cytometry, and constructed ESC line with stable expression of Pdx1 and negative control ESC line were verified. RESULTS (1) The positive rates of transfected cells in PDX1- ESC group and PDX1+ ESC group were 90.72% and 94.01% after screening by DOX, respectively. The positive rates of transfected cells in PDX1- ESC group and PDX1+ ESC group was 97.84% and 98.13% after sorting by flow cytometry, respectively. (2) With DOX, green fluorescence was observed in PDX1- ESC group and PDX1+ ESC group. The mRNA and protein expression of Pdx1 was significantly increased in PDX1+ ESC group (P <0.05). Without DOX, no green fluorescence was observed in the cells of the 3 groups, and no significant difference in the mRNA and protein expression of Pdx1 was observed (P >0.05). (3) After 3 months of cryopreservation, the cell lines still survived in resuscitation culture and were regulated by DOX. CONCLUSION Using Tet-On system, the mouse ESC line with inducible Pdx1 expression were successfully established and could be used as an effective cell model to research the differentiation of Pdx1+ definitive endoderm cells into pancreatic cells. 相似文献
98.
经电镜扫描寡齿新银鱼的第Ⅳ时相,第Ⅴ时相卵母细胞和受卵的卵细胞粘丝,结果表明,卵细胞表面具从受精孔发生的12根左右粘丝,此粘丝于受精孔处微弱弯曲,经侧部渐向受精孔相对处呈现很强扭曲或互相缠绕。卵细胞粘丝不仅出现在受精卵和第Ⅴ时相卵母细胞表面,而且清晰地出现在第Ⅳ时相卵母细胞的滤泡膜上。 相似文献
99.
大银鱼卵细胞粘丝扫描电镜观察 总被引:1,自引:0,他引:1
用扫描电镜观察了大银鱼的第Ⅲ时相,第Ⅳ时相,第Ⅴ时相卵母细胞和受精卵的卵细胞粘丝的外部形态特征和它们的粘性,并讨论了卵细胞粘丝的功能。 相似文献
100.
Litong Liu Xu Yang Pengfei Yuan Shanshan Cai Jing Bao Yanan Zhao Alimu Aimaier Adila Aipire Jun Lu Jinyao Li 《Marine drugs》2022,20(3)
Low molecular weight fucoidan (LMWF) has been reported to have immunomodulation effects through the increase of the activation and function of macrophages. In this study, the regulating effect of LMWF from Undaria pinnatifida grown in New Zealand on dendritic cells (DCs) was investigated. We discovered that LMWF could stimulate DCs’ maturation and migration, as well as CD4+ and CD8+ T cells’ proliferation in vitro. We proved that this immune promoting activity is activated through TLR4 and its downstream MAPK and NF–κB signaling pathways. Further in vivo (mouse model) investigation showed that LMWF has a strong immunological boosting effect, such as facilitating the proliferation of immune cells and increasing the index of immune organs. These findings suggest that LMWF has a positive immunomodulatory effect and is a promising candidate to supplement cancer immunotherapy. 相似文献