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81.
仙人掌提取物对小鼠T淋巴细胞增殖的影响   总被引:1,自引:1,他引:1  
目的探讨仙人掌提取物对小鼠T淋巴细胞增殖的影响。方法将30只小鼠随机等分为空白对照组、实验组和阳性对照组。空白对照组用生理盐水20mg·kg-1灌胃,实验组用仙人掌提取物5mg·kg-1灌胃,阳性对照组用胸腺肽5mg/只灌胃,每日1次,10d后酶染法检测外周血酸性α-醋酸萘酯(ANAE)阳性率,MTT法检测小鼠胸腺T淋巴细胞增殖。结果与空白对照组相比,实验组小鼠外周血ANAE阳性率增高、胸腺T淋巴细胞增殖明显(P<0.05),与阳性对照组比较则无显著差异(P>0.05)。结论仙人掌提取物对小鼠T淋巴细胞的增殖有促进作用。  相似文献   
82.
目的研究转染低氧诱导因子-1α突变型(hypoxiainduciblefactor-1α^mu,HIF-1α^mu)后的外源性内皮祖细胞(endothelialprogenitorcells,EPCs)中CXCL12的表达情况及对EPCs的影响。方法密度梯度离心结合差速贴壁法分离、培养EPCs并进行鉴定;以Adv—HIF-1α^mu的最佳转染指数转染EPCs,获得含有目的基因处理的EPCs细胞,设为A组。B组为单纯转染Adv的EPCs。设未转染Adv—HIF-1α^mu的EPCs为C组。WesternBlot检测转染后的EPCs中HIF-1的表达,检测转染后的EPCs培养液上清液中的CXCL12浓度及其对外源性EPCs迁移的影响。结果密度梯度离心结合差速贴壁法获得的EPCs能够结合UEA-1和摄取ac—LDL,并具有成血管作用;转染Adv—HIF-1α^mu的EPCs表达的HIF-1及CXCL12高于单纯转染Adv的EPCs及未转染Adv—HIF-1α^mu的EPCs(P〈0.05),且能诱导外源性EPCs的迁移。结论密度梯度离心结合差速贴壁法能够分离、培养符合特征的EPCs,转染Adv—HIF-1α^mu的EPCs能够在常氧条件下高表达HIF-1及CXCL12,并诱导外源性EPCs的迁移。  相似文献   
83.
目的 通过建立重力打击式小鼠外伤性视神经病变模型探讨外伤性视神经病变的发病机制.方法 选取SPF级C57BL/6J成熟小鼠48只(96眼),均取小鼠左眼为实验眼进行造模,右眼为对照眼不做处理.采用重力打击建立小鼠外伤性视神经病变模型,造模后第1、3、5、7天对小鼠进行观察,每个时间点取6只小鼠进行闪光视觉诱发电位检查、...  相似文献   
84.
《Drug metabolism reviews》2012,44(1-2):89-116
Dehydroepiandrosterone has been thought to have physiological functions other than as an androgen precursor. The previous studies performed have demonstrated a number of biological effects in rodents, such as amelioration of disease in diabetic, chemical carcinogenesis, and obesity models. To date, activation of the peroxisome proliferators activated receptor alpha, pregnane X receptor, and estrogen receptor by DHEA and its metabolites have been demonstrated. Several membrane-associated receptors have also been elucidated leading to additional mechanisms by which DHEA may exert its biological effects. This review will provide an overview of the receptor multiplicity involved in the biological activity of this sterol.  相似文献   
85.
目的 探讨三磷酸腺苷(ATP)对肌源性干细胞(MDSCs)凋亡的抑制作用及其机制.方法 采用差速贴壁法分离新生小鼠MDSCs,利用40μg/L肿瘤坏死因子(TNF)-α诱导MDSCs凋亡,100 μmol/L ATP抑制细胞凋亡.经流式细胞仪检测MDSCs的凋亡率和半胱氨酰天冬氨酸特异性蛋白酶( Caspase) -3/8的表达.结果 TNF-α诱导后,脱壁细胞明显增多,MDSCs的凋亡率由5.17%升至31.58%,增加了5倍,Caspase-3染色阳性细胞率由5.01%增至19.25%,Caspase-8染色阳性细胞率由2.97%增至8.58%.ATP作用后,MDSCs的凋亡率降至12.06%,减少了2/3,Caspase-3染色阳性细胞率降至9.86%,Caspase-8染色阳性细胞率降至6.96%,但仍高于对照组.结论 ATP能抑制MDSCs表达Caspase-3/8,减轻TNF-α诱导的MDSCs凋亡.  相似文献   
86.
The process of red sorghum malt production was monitored three times in five production units (PU) selected upon their ability to produce malt flours having a high capacity to fluidify high-energy-density gruels. Raw, germinated and degermed seeds were analysed for macronutrient, soluble sugars, phytate and cyanide contents and α-amylase activity. Know-how differences between producers lay mainly in the duration and type of equipment used for steeping and germination. Moreover, three PUs applied a maturation step before sun-drying and one PU added ashes to steeped seeds before germination. No significant difference was detected in the proximate composition of malts from the five PUs. For all PUs, traditional malting increased the protein content and decreased the lipid and ash contents, while the fibre content was not affected. Significant increases in sugar contents and in α-amylase activity were observed but in variable proportions from one PU to another. The phytate content decreased significantly in all PUs. The cyanide content increased in all PUs but more drastically or less drastically according to the PU. Finally, degerming lowered the cyanide content to an acceptable level for human consumption. The between-PU variability may be due either to the nature and origin of the raw seeds or to technological know-how differences between producers. Further investigations are needed to optimize and standardize the malting process with a view to maximizing α-amylase and phytase activities and minimizing the variability of their biochemical characteristics.  相似文献   
87.
Anthocyanins can be considered spy-substances, useful in obtaining information regarding the shelf-life of food supplements containing cranberry juice or cranberry-derived extracts. The level of total anthocyanins, as evaluated by high-performance liquid chromatography-diode-array detector and analytically expressed as cyanidin aglycone, represents a ‘quality index’ useful for routine estimation of shelf-life. The objective of this work was to study the stability of anthocyanins in a commercial cranberry (Vaccinium macrocarpon) dried extract compared with the stability of the same extract contained in a food supplement enriched with α-tocopheryl succinate and ascorbic acid. The values obtained after exposure of the samples to natural light and to alternating hot and cold temperatures show considerable sensitivity of the commercial cranberry dried extract to the agents used for the same evaluation (time, temperature and light) and emphasize a positive effect of the enrichment of the derived preparation with α-tocopheryl succinate and ascorbic acid.  相似文献   
88.
《Hemoglobin》2013,37(2):205-207
We report a case of α+-thalassemia (α+-thal) trait caused by a novel frameshift mutation in exon 2 of the α2-globin gene, specifically a deletion of a single nucleotide at amino acid codon 81 [HBA2 c.244delT]. The mutation results in a premature termination of translation at codon 83.  相似文献   
89.
Various factors have been described as phenotypic modulators of sickle cell disease, such as levels of fetal hemoglobin (Hb F), presence of α-thalassemia (thal), and haplotypes of the β-globin genes. In order to characterize and determine the frequency of the βS and βC mutations and the prevalence of ?α3.7-thal, 74 patients with sickle cell disease detected during neonatal screening in the State of Pernambuco, Brazil, were studied. The haplotypes of the β gene and ?α3.7-thal were determined using polymerase chain reaction (PCR), and specific restriction endonucleases were used to establish the polymorphic sites of the haplotypes. The results showed the high frequency of the Central African Republic (CAR) or Bantu haplotype in the State of Pernambuco, Brazil. The low frequency of the Benin haplotype recorded in this study, in comparison with other states in northeast Brazil, suggests the diversity of origins of Afro-Brazilians in this region.  相似文献   
90.
《Hemoglobin》2013,37(2):148-159
α-Thalassemia (α-thal) is usually caused by deletions on the α-globin gene cluster and the role of point mutations is less well investigated. In the present study, a total of 1048 individuals with hypochromic microcytic anemia, who did not present the most common α-thal deletions, were referred for α-globin gene DNA sequencing. The nucleotide changes were studied and a total of five new mutations was identified, of which three were located on the α2 gene [codon7 (Lys→Stop), codon 34 (Leu→Pro) and codon 83 (Leu→Arg)] and two on the α1 gene [IVS-I-116 (A>G) and codon 44 (+C)]. These novel mutations not only explain new findings by molecular analysis of the α-globin gene but also have clinical importance due to their changes in α-globin production in means of decreased hemoglobin (Hb) related values. Moreover, considerations of its role in combination with other mutations, and the possibility of causing Hb H (β4) are yet to be studied.  相似文献   
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