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91.
92.
随机抽取306份不同白蛋白( Alb)浓度的新鲜血清标本,分别用溴甲酚绿法( BCG)、改良溴甲酚紫法( mBCP)、免疫比浊法( ITA )检测 Alb 浓度,液态酶法检测糖化白蛋白( GA) ,并计算GA值[ GA%(%) =GA/Alb × 100%]. 正常Alb浓度( Alb≥ 40 g/L )时, BCG 与 mBCP 法、BCG 与 ITA法、mBCP与ITA法检测结果比较,临床差异不明显,而且GA% BCG与GA% mBCP比较,差异无统计学意义( P=0. 537 );低Alb浓度( Alb<40 g/L)时,BCG法分别与mBCP、ITA法比较差异有统计学意义( P < 0. 01 ) , GA% BCG明显低于GA% mBCP ( P <0. 01 ). 故正常 Alb 浓度时, BCG、mBCP 与ITA 法三者结果差异无明显临床意义,各法用于GA%计算无明显差异;但低Alb浓度时,mBCP与ITA法二者一致性优于BCG与ITA法,若使用BCG法则GA%结果可能被低估. 相似文献
93.
目的观察绿色荧光蛋白( GFP)标记的兔骨髓间充质干细胞( BMSCs)成骨诱导后形态学改变和体外骨生成中矿化钙结节的形成,并结合扫描电镜和X射线能谱分析技术( SEM/EDS)对矿化钙结节元素进行定量能谱分析。方法
用携带GFP基因的腺病毒转染兔BMSCs进行示踪标记,并诱导细胞向成骨方向分化,通过倒置荧光显微镜、钙结节茜素红染色观察成骨诱导后细胞形态改变和矿化钙结节的形成,结合SEM/EDS技术观测矿化钙结节的表面微观结构及其元素构成。结果腺病毒介导GFP基因( Ad-GFP )转染兔 BMSCs后在荧光显微镜下观察到绿色荧光,经成骨诱导后细胞形态向成骨方向分化,并形成不透光的矿化钙结节,钙结节茜素红染色见红色矿化结节,SEM下见矿化钙结节散布于细胞中,细胞重叠生长,分泌基质旺盛。 EDS分析显示矿化钙结节主要组成元素与正常骨组织相同,其钙磷比(Ca/P)为1.55,接近正常骨组织钙磷比1.49。结论 Ad-GFP能成功转染并标记兔BMSCs,成骨诱导后BMSCs向成骨方向分化,具备较好的骨生成能力,BMSCs体外矿质化成骨过程与体内基本相同。 相似文献
用携带GFP基因的腺病毒转染兔BMSCs进行示踪标记,并诱导细胞向成骨方向分化,通过倒置荧光显微镜、钙结节茜素红染色观察成骨诱导后细胞形态改变和矿化钙结节的形成,结合SEM/EDS技术观测矿化钙结节的表面微观结构及其元素构成。结果腺病毒介导GFP基因( Ad-GFP )转染兔 BMSCs后在荧光显微镜下观察到绿色荧光,经成骨诱导后细胞形态向成骨方向分化,并形成不透光的矿化钙结节,钙结节茜素红染色见红色矿化结节,SEM下见矿化钙结节散布于细胞中,细胞重叠生长,分泌基质旺盛。 EDS分析显示矿化钙结节主要组成元素与正常骨组织相同,其钙磷比(Ca/P)为1.55,接近正常骨组织钙磷比1.49。结论 Ad-GFP能成功转染并标记兔BMSCs,成骨诱导后BMSCs向成骨方向分化,具备较好的骨生成能力,BMSCs体外矿质化成骨过程与体内基本相同。 相似文献
94.
Differentiation of in vitro-modified human peripheral blood monocytes into hepatocyte-like and pancreatic islet-like cells 总被引:16,自引:0,他引:16
95.
Wenfeng Li Nianwu He Lingmin Tian Xiaolong Shi Xingbin Yang 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2016,24(3):527
A polyphenol-enriched extract from selenium-enriched Ziyang green tea (ZTP) was selected to evaluate its antitumor effects against human breast cancer MCF-7 cells. In ZTP, (−)-epigallocatechin gallate (28.2%) was identified as the major catechin, followed by (−)-epigallocatechin (5.7%) and (−)-epicatechin gallate (12.6%). ZTP was shown to inhibit MCF-7 cell proliferation (half maximal inhibitory concentration, IC50 = 172.2 μg/mL) by blocking cell-cycle progression at the G0/G1 phase and inducing apoptotic death. Western blotting assay indicated that ZTP induced cell-cycle arrest by upregulation of p53 and reduced the expression of CDK2 in MCF-7 cells. ZTP-caused cell apoptosis was associated with an increase in Bax/Bcl-2 ratio, and activation of caspase-3 and -9. MCF-7 cells treated with ZTP also showed an overproduction of reactive oxygen species, suggesting that reactive oxygen species played an important role in the induction of apoptosis in MCF-7 cells. This is the first report showing that ZTP is a potential novel dietary agent for cancer chemoprevention or chemotherapy. 相似文献
96.
97.
Maria Kuraska Elbieta Malewska Krzysztof Polaczek Aleksander Prociak Joanna Kubacka 《Materials》2020,13(22)
In order to create greener polyurethane (PUR) foams, modified used cooking oils (UCO) were applied as starting resources for the synthesis of bio-polyols. The bio-polyols were produced using transesterification of UCO with diethylene glycol (UCO_DEG) and triethanolamine (UCO_TEA). Next, open-cell PUR foams were synthesized by replacing 20, 40, 60, 80 and 100% of the petrochemical polyol with the bio-polyol UCO_DEG or UCO_TEA. It was observed that an increasing bio-polyol content (up to 60%) led to an increase of the closed cell content. However, a further increase in the bio-polyol content up to 100% resulted in foam cell opening. The bio-foams obtained in the experiment had an apparent density of 13–18 kg/m3. The coefficient of thermal conductivity was determined at three different average temperatures: 10, 0 and −10 °C. The PUR bio-foams modified with bio-polyol UCO_TEA had lower values of thermal conductivity, regardless of the average temperature (35.99–39.57 mW/m·K) than the foams modified with bio-polyol UCO_DEG (36.95–43.78 mW/m·K). The compressive strength of most of the bio-foams was characterized by a higher value than the compressive strength of the reference material (without bio-polyol). Finally, it was observed that the bio-materials exhibited dimensional stability at 70 °C. 相似文献
98.
Vicente Colomer-Romero Dante Rogiest Juan Antonio García-Manrique Jose Enrique Crespo 《Materials》2020,13(24)
Bio- and green composites are mainly used in non-structural automotive elements like interior panels and vehicle underpanels. Currently, the use of biocomposites as a worthy alternative to glass fibre-reinforced plastics (GFRPs) in structural applications still needs to be fully evaluated. In the current study, the development of a suited biocomposites started with a thorough review of the available raw materials, including both reinforcement fibres and matrix materials. Based on its specific properties, hemp appeared to be a very suitable fibre. A similar analysis was conducted for the commercially available biobased matrix materials. Greenpoxy 55 (with a biocontent of 55%) and Super Sap 100 (with a biocontent of 37%) were selected and compared with a standard epoxy resin. Tensile and three-point bending tests were conducted to characterise the hemp-based biocomposite. 相似文献
99.
Chao-Lin Kuo Tung-Sheng Chen Shaw-Yih Liou 《Immunopharmacology and immunotoxicology》2014,36(5):364-370
Green tea is a widely consumed beverage known for its beneficial anti-inflammatory, anti-oxidative, anti-mutagenic, anti-carcinogenic, and cardioprotective properties. Here, we administered epigallocatechin gallate fraction of green tea extract (EGTE) to mice for 6 weeks and examined the effects on the innate and adaptive immune responses by measuring phagocytic and natural killer (NK) cell activity, as well as antigen-specific proliferation, cytolysis, cytokine secretion, and antibody production. Our data show that EGTE administration increased NK cell cytolysis and peritoneal cell phagocytosis, as well as splenocyte proliferation and secretion of IL-2 and IFN-γ. Of note, EGTE treatment decreased the production antigen-specific IgE via increased the proportion of CD4+ CD25+ regulatory T lymphocytes in the spleen, suggesting that EGTE may play a role in regulating the allergic response. 相似文献
100.
《Acta histochemica》2014,116(8):1307-1312
Peroxisomes lack their own genetic material and must therefore import proteins encoded by genes in the nucleus. Amino acids within these proteins serve as targeting signals: they direct the delivery of the proteins to the organelle. The majority of soluble proteins destined for the peroxisomal matrix utilize a type 1 peroxisomal targeting signal (PTS1): a C-terminal tripeptide that follows the pattern small/basic/hydrophobic. We have discovered two new C-terminal tripeptides that target proteins to peroxisomes in Arabidopsis thaliana. The tripeptides PSL and KRR do not fit the major PTS1 consensus but cause green fluorescent protein to accumulate in peroxisomes of stably transformed Arabidopsis. We have identified forty-one proteins in the Arabidopsis genome that also bear these tripeptides at their C-termini and may therefore be peroxisomal. 相似文献