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101.
102.
Previous studies have shown that the maintenance and proliferation of undifferentiated rhesus monkey embryonic stem (rES) cells requires medium supplemented with fetal bovine serum (FBS). Due to the uncharacterized composition and variation in serum nature, the present study aimed to replace the serum-containing medium with a serum-free medium in the rES cell culture. The results showed that after the initial 48-h culture in the routinely used serum-containing medium, rES cells can grow and proliferate for a prolonged period in the serum-free medium composed of DMEM supplemented with a cocktail of BSA, IGF-1, TGF- f, bFGF, aFGF, estradiol, and progesterone. rES cells cultured in the serum-free medium maintained high level of alkaline phosphatase activity and OCT4 level. There was no indication of differentiation as judged by the marker gene expression of all three embryonic germ layers and trophoblast. In addition, serum-free culture would not affect the passage capacity and differentiation potential of rES cells. This work will facilitate the future study of induced differentiation of rES cells and other applications. 相似文献
103.
携Sialyl Lewis^X超声微泡靶向探查缺血心肌的炎症分子“印记” 总被引:1,自引:1,他引:1
目的探讨应用靶向超声分子成像探查心肌缺血再灌注损伤炎症“印记”的可行性。方法采用“亲和素-生物素”桥接法构建携唾液酸化路易斯(Sibyl Lewis^X)靶向超声微泡(MBsLex)和同型对照微泡(MBc)。10只心肌缺血再灌注小鼠随机先后注入MBsLex和MBc(间隔30min),分别于注入5min后行心肌对比超声检查,测量心肌缺血区和非缺血区的声强度(Ⅵ)。结果对比超声图像显示MBsLex组缺血区心肌造影见显著增强,Ⅵ值高达23.52±1.08,而在MBc组缺血区心肌造影仅见轻度增强,Ⅵ缸为9.81±0.41,两者之间差异有统计学意义(P〈0.05)。但无论MBsLex组还是MBc组,缺血区心肌Ⅵ值均明显高于非缺血区心肌Ⅵ值(P〈0.05)。两组非缺血区心肌之间Ⅵ值未见明显差异。结论应用携sLex超声微泡行对比超声能够靶向探查心肌缺血再灌注损伤的炎症“印记”。 相似文献
104.
〔摘 要〕 目的:探讨来那度胺联合 VAD 方案治疗多发性骨髓瘤患者的临床疗效及安全性。方法:选取 2018 年 5 月 至 2020 年 5 月期间于南阳市第二人民医院治疗的 86 例多发性骨髓瘤患者为研究对象,随机分为观察组和对照组,
各 43 例,对照组采用 VAD 方案进行治疗,观察组在对照组的基础上加用来那度胺胶囊。比较两组患者的临床疗效、
治疗前后的血红蛋白(HGB)及白蛋白(Alb)以及骨髓浆细胞比率、不良反应发生率。结果:观察组患者的治疗总
有效率为 81.40 %,较对照组的 60.47 % 更高,差异具有统计学意义(P < 0.05);治疗 4 个月后,与治疗前相比,
两组患者的骨髓浆细胞比率均明显下降,HGB 及 Alb 均明显上升,而观察组骨髓浆细胞比率低于对照组,HGB 及
Alb 高于对照组,差异均具有统计学意义(P < 0.05);两组患者治疗期间的不良反应总发生率比较,差异无统计学
意义(P > 0.05)。结论:来那度胺联合 VAD 方案治疗多发性骨髓瘤患者的临床效果较单一 VAD 方案治疗更佳,且
安全性较高。 相似文献
105.
106.
Rapid method for isolation of normal human peripheral blood eosinophils on discontinuous Percoll gradients and comparison with neutrophils 总被引:10,自引:0,他引:10
Previous studies on human eosinophils often have used cells from patients with hypereosinophilia syndrome or parasitosis owing to the difficulty in isolating pure populations of eosinophils from normal individuals. In the present study, human eosinophils were isolated with a purity of 97%, with 70% recovery from normal individuals with blood eosinophil counts of less than 3%. Human eosinophils are denser than neutrophils, but the range of densities of the two cell types overlap, making purification of eosinophils by density-gradient centrifugation difficult. However, if neutrophils were exposed to the chemotactic peptide (f-Met-Leu-Phe), which did not stimulate eosinophils, the neutrophils' density decreased, shifting them away from the density of eosinophils. Whole normal blood anticoagulated with EDTA was incubated at 37 degrees C for 15 minutes with 10(-6) mol/L f-Met-Leu-Phe and then layered over a discontinuous Percoll gradient (65% and 75% in diluted phosphate-buffered saline) and centrifuged at 400 g for 25 minutes at 22 degrees C. The cell layer between the 65% and 75% Percoll was collected and washed, and hypotonic lysis was used to remove erythrocytes. This cell layer contained 97.3 +/- 0.7% eosinophils (N = 8) with a yield of 4.9 X 10(4) eosinophils per milliliter of whole blood, or 70% of the total eosinophil count. The isolated eosinophils were in a quiescent state but responded to Escherichia coli endotoxin- activated serum with shape change and chemotaxis, membrane depolarization, and reduced nitroblue tetrazolium (96.0 +/- 1.0%), when stimulated with phorbol myristate acetate. In phagocytic assays, 89.3 +/- 1.3% of the eosinophils ingested Candida albicans v 96.0% +/- 1.0% of neutrophils. In contrast, the eosinophils did not respond chemotactically, alter membrane potential, or reduce nitroblue tetrazolium when treated with f-Met-Leu-Phe, and studies with f-Met-Leu- [3H]Phe showed that normal eosinophils lacked expression of receptors for f-Met-Leu-Phe. In control studies, normal eosinophils that were not exposed to f-Met-Leu-Phe during purification also failed to respond to f-Met-Leu-Phe, indicating intrinsic differences between normal eosinophils and neutrophils. Thus, exposure of whole blood to f-Met-Leu- Phe, followed by separation on Percoll is a simple method for rapid isolation of normal human eosinophils. 相似文献
107.
Gerhard Adam Jrg Neuerburg Elmar Spüntrup Andreas Mühler Kira Scherer Vet Surg Rolf W. Günther 《Journal of magnetic resonance imaging : JMRI》1994,4(3):462-466
Gadolinium-DTPA (diethylenetriaminepentaacetic acid)-cascade-polymer, a potential new blood pool contrast agent for magnetic resonance (MR) imaging, was compared with a known blood pool agent, Gd-DTPA-polylysine, in an animal model. The relative signal intensities of liver, renal cortex, pancreas, and trunk muscle were assessed in 12 pigs between 4 seconds and 120 minutes after injection of a 20 μmol/kg dose of each contrast agent, by using a FLASH (fast low-angle shot) sequence. Except for muscle, all tissues showed visible enhancement after injection of either contrast agent. After injection of Gd-DTPA-polymer, enhancement patterns in the liver, renal cortex, and pancreas were similar to those seen after injection of Gd-DTPA-polylysine. No statistically significant differences in enhancement between the two contrast agents were found at any time point. The authors conclude that the contrast kinetics of Gd-DTPA-cascade-polymer are similar to those of Gd-DTPA-polylysine and that this agent may also be used as a blood pool contrast agent for MR imaging. 相似文献
108.
目的为特异性地将病毒性白细胞介素10(vIL10)基因转移到肾脏提供一种手段。方法应用逆转录病毒载体介导的基因转移技术将外源性基因vIL10转移到大鼠肾脏系膜细胞,应用RTPCR、ELISA方法检测其表达,并通过对混合淋巴细胞反应(MLR)的影响对其活性进行分析。结果vIL10在转染的系膜细胞表达20000pg·(106细胞)-1/24h,应用3HTdR掺入法检测vIL10对MLR的影响,实验组明显低于对照组(P<005)。结论外源性基因在系膜细胞有效地转录和表达,并对MLR有抑制作用。 相似文献
109.
对一株从土壤中筛选出来的产蓝色素的放线菌进行了初步鉴定, 命名为天蓝色链霉菌-100(Streptom yces coelicolor-100 ),并对蓝色素的性质进行了研究.结果表明此色素无臭无味,水溶性较强.酸性条件下,溶解度随pH 降低而减小.pH< 8 时为红色,pH≥8 时为蓝色,颜色随pH 增大而加深.于100 ℃短时间处理,比较稳定.在pH 中性的条件下对光(包括紫外光)较稳定.大多数金属离子如Ba2+ 、K+ 等对此色素无影响,Mg2+ 使色素增色.Fe2+ 在5×10-4 m ol/L时,使色素变性,但在5×10-5 m ol/L时,对色素没有多大影响.Pb2+ 可以络合色素,使之沉淀;加入0.25% 盐酸乙醇后,色素再溶解.该蓝色素可作为天然色素或天然pH 指示剂开发. 相似文献
110.
血小板激活因子对急性重型胰腺炎肺损伤作用的实验研究 总被引:2,自引:0,他引:2
目的 探讨血小板激活因子( Platelet Activating Factor, P A F) 在急性胰腺炎肺损伤发生发展中的作用。 方法 17 只纯种 Beagle 狗分成三组:(1) 胰腺炎组( P 组) ,用牛磺胆酸钠加胰蛋白酶主胰管逆行注射,复制急性胰腺炎模型;(2) 治疗组( T 组) ,模型复制后5 分钟,3 小时分别静脉注射苦杏内酯 B( B N52021) ;(3) 对照组( C 组) 。分别测定平均肺动脉压值,肺湿重系数,支气管肺泡灌洗液( Bronchial Alveolar Lavage Fluid , B A L F) 内细胞总数和蛋白含量,肺血管外水量/ 无血干肺重( Extra Vascular Lung Water / Blood Free Dry Lung , E V L W/ B F D L) ,肺组织内 P A F含量。 结果 平均肺动脉压值 P组明显升高,在4 小时与 C组、 T组差异均有显著意义( P< 005) 。 P组肺系数〔(112 ±006) % ,珋x ±s ,以下同)〕, E V L W/ B F D L(559 ±053) 及 B A L F中细胞总数〔(203 ±002) ×109/ L〕和蛋白含量〔(447 ± 相似文献