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51.
AIM:To investigate an effective and stable method to isolate myocardial microvascular endothelial cells (MMVECs) from the mouse heart and to observe their biological characteristics.METHODS:The cells from the mouse heart were isolated by collagenase II digestion followed by different speed adhesion. Then the cells were cultured on the dish coated with polylysine in endothelial cell-specific culture medium. The biological characteristics were observed by trypan blue staining. The cell growth curve and the cell proliferation were also evaluated by MTT assay at different passages. The expression of DiI-ac-LDL, FITC-UEA-1, specific markers of endothelial cells and the expression of CD31, vWF and CD34 were determined by immunofluoresence staining. To evaluate the function of the MMVECs, in vitro tube formation was evaluated under microscope.RESULTS:Two days after the enzyme digestion, the MMVECs formed small and isolated clusters. The MMVECs grew quickly in monolayer with the characteristics of endothelial cell shape at 4~5 d. The cells became confluent and cobblestone-like which were ready for passage at 7~8 d. After passage, the viability of the cells was more than 95%. The first and the third generation of the cells presented an S-shape growth curve. The cell proliferation of the first to the third generation was quick and slowed down after the fifth passage. MMVECs were highly positive for DiI-ac-LDL and FITC-UEA-1 [(89.2±3.5)%], indicating the cells were MMVECs. The other relative antigen expression (CD31, vWF and CD34) on the MMVECs was (56.7±3.7)%, (78.5±2.6)% and (67.8±4.2)%, respectively. The MMVECs formed the tubes in vitro after cultured for 6~12 h.CONCLUSION:We can obtain high-purity MMVECs using the combination of collagenase II digestion, the different speed adhesion process and the endothelial cell-specific culture medium for effective and reliable MMVECs isolation and culture.  相似文献   
52.
以氯化钙为主要原料,添加磷酸钙和羟乙基纤维素,制备了钙磷胶体复合剂,经检测含钙量为115±5mg/mL、含磷量为16.4±2mg/mL.试验小鼠n=20以0.8mL/20g(体重)的最大剂量一日灌服2次,7d后观察无中毒表现,剖检后组织器管无肉眼可见异常.试验组小鼠n=20以0.4mL/20g(体重)的剂量一日2次连续灌服7d后,无中毒及死亡现象,小鼠平均体重由20.24±1.211g增加到23.35±1.130g,体重增加情况与对照组小鼠无差异.以100mL/只灌服奶山羊(n=5)后,血钙、血磷浓度在2~3h达到峰值(P<0.05),而且可维持6h左右.  相似文献   
53.
Helicteres isora root extracts were studied for antinociceptive activity on acetic acid-induced writhing test in mice, at a dose of 250 mg/kg. Petroleum ether, chloroform and aqueous ethanol extracts have shown significant activity.  相似文献   
54.
对超数排卵的小鼠分别在注射HCG后14~16, 16~18, 18~20和20~22 h采小鼠卵母细胞用于 核移植, 观察小鼠卵母细胞的去核时间在体细胞核移植中的作用。结果显示, 在注射hCG后14~16, 16~18, 18~20和20~22 h, 小鼠卵母细胞去核效率分别为80.09 %(338/422), 73.12 %(283/387), 55.02 %(230/418)和48.74 %(193/396); 重构胚激活率分别为 66.20 %(190/287), 75.43 %(175/232), 84.78 %(156/184)和85.14 %(126/ 148); 重构胚的囊胚发育率分别为13.94 %(40/287), 7.33 %(17/232), 3.80 %(7/184)和1.35 %(2/148)。试验证实小鼠卵母细胞在注射hCG后14~16 h进行去核较为适宜。  相似文献   
55.
The ethanol extract of leaves of Derris uliginosa given by oral route at dose of 250 and 500 mg/kg produced a significant inhibition on acetic acid-induced writhing in mice.  相似文献   
56.
结果表明 ,鹿茸醇提物组 (即实验组 )小白鼠红细胞的C3b受体酵母菌花环率为( 1 3 5± 0 2 ) %,对照组为 ( 1 0 1± 0 1 ) %,两组相比较 ,差异显著 (P <0 0 5) ;试验组小白鼠红细胞的免疫复合物酵母菌花环率为 1 1 3± 0 2 %,对照组为 1 6 3± 0 3%,两组相比较 ,差异显著 (P <0 0 5)。这一试验结果提示 ,鹿茸醇提物可增强由环磷酰胺诱导的免疫功能低下的小白鼠红细胞的免疫功能 ,即鹿茸醇提物对于环磷酰胺对机体的副作用具有一定的对抗作用。  相似文献   
57.
收集了黑龙江省4个国有林区(哈尔滨、牡丹江、佳木斯和伊春林区)39个林业局11种主要害虫和1类害鼠的发生资料和气象资料。这11种害虫和1类害鼠基本代表了黑龙江林区的虫害和鼠达发生的优势种类。通过相关分析和多元线性回归。建立了21个预报模型。模型的F检验相关系数为0.85以上。回报准确率达85%以上。这些模型可用于黑龙江省国有林区主要害虫和害鼠发生量趋势预报。  相似文献   
58.
不同激素剂量对幼鼠超数排卵及超排卵质量的影响   总被引:8,自引:0,他引:8  
应用国产激素制剂对3~8周龄昆明种小白鼠进行了超数排卵处理,重点观察了不同激素剂量对幼龄小鼠的超排效果及超排卵质量的影响。实验结果表明,以PMSG与hCG各10IU剂量超排3~8周龄小鼠,5周龄小鼠的超排效果(平均获卵83.8±10.2个)极显著(P<0.01)好于4~8周龄小鼠的超排效果(平均获卵39.2~49.8个),而3周龄小鼠超排卵受精后体外培养的卵裂率(97.1%)、桑椹胚率(86.8%)和囊胚率(65.1%)与4~8周龄超排卵的(分别为85.5%~100.0%、94.9%~100.0%和63.2%~87.7%)相近;以PMSG与hCG各5IU剂量超排3~5周龄小鼠,3周龄小鼠的超排效果(平均获卵59.0±6.5个)显著(P<0.05)好于4周龄小鼠的超排效果(平均获卵31.4±4.9个),并极显著(P<0.01)好于5周龄小鼠的超排效果(平均获卵21.4±3.3个);以PMSG与hCG各15IU剂量超排3~5周龄小鼠,3周龄小鼠的超排效果(平均获卵48.6±7.3个)显著(P<0.05)好于5周龄小鼠的超排效果(平均获卵25.2±5.8个),也好于4周龄小鼠的超排效果(平均获卵40.2±5.1个  相似文献   
59.
AIM: Cystostomy is the traditionary method for detecting urodynamic indexes in mice, which destroys the continuity of the bladder, and there are significant differences between this method and the clinically used trans-urethral method. This study aims to develop an appropriate urethral catheter to investigate the advantages and application value of transurethral method for urodynamic test. METHODS: A pediatric intravenous catheter was used for urethral catheterization on 8 female mice, and linked to connect the catheter to baroreceptor and micropump. The epidural catheter was also used as manometry tube. RESULTS: Using this method, the following urodynamic indicators has been successfully captured: basal bladder pressure (BBP), bladder leak point pressure (BLPP), maximum voiding pressure (MVP), maximum bladder capacity (MBC), post-void residual urine volume (PVR), voiding volume (VV), efficiency of voiding (EV) and bladder compliance (BC). CONCLUSION: This is the first successful simulation used in human body to achieve mouse urodynamic testing through the urethra catheter, which avoids the impact of cystostomy on urodynamics in mice, and the mice are able to keep long-term survival after tests for the follow-up molecular and genetic experiments.  相似文献   
60.
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