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71.
以糖尿病患者为研究对象(15名为Ⅰ型糖尿病患者,15名为Ⅱ型糖尿病患者),通过对他们进行3个月的有氧运动干预,观察糖尿病患者运动前后的血栓调节蛋白、T-PA活性、PAI-1活性等指标的变化,明确运动对糖尿病患者血栓调节蛋白和纤溶系统的影响,从而反映运动对糖尿病患者血管内皮的影响,为指导糖尿病患者运动提供理论依据。实验结果:1.实验前Ⅰ型、Ⅱ型糖尿病患者的TM均高于对照组且差异显著;实验后,Ⅰ型、Ⅱ型糖尿病患者的TM均下降,与实验前相比,有显著性差异。2.Ⅰ型糖尿病患者在实验后比实验前PAI-1有明显增加;Ⅱ型糖尿病患者在实验前后PAI-1无显著性差异。结论:实验后TM的下降可能反映了糖尿病患者内皮功能的改善,可以减少心血管疾病的风险。  相似文献   
72.
Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, che-mopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinoeyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage.  相似文献   
73.
Objective: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAMNEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion: With a low toxicity, high safety, and high transfection rate, G4PAMAMNEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.  相似文献   
74.
Objective: In this paper we compared the two methods of cell sorting (magnetic cell sorting and flow cytometry sorting) for the isolation and function analysis of mouse CD4~+ CD25~+ regulatory T (Treg) cells, in order to inform further studies in Treg cell function. Methods: We separately used magnetic cell sorting and flow cytometry sorting to identify CD4~+ CD25~+ Treg cells. After magnetic cell separation, we further used flow cytometry to analyze the purity of CD4~+ CD25~+ Treg cells, trypan blue staining to detect cell viability, and propidium iodide (PI) staining to assess the cell viability. We detected the immune inhibition of CD4~+ CD25~+ Treg cells in the in vitro proliferation experiments. Results: The results showed that compared to flow cytometry sorting, magnetic cell sorting took more time and effort, but fewer live cells were obtained than with flow cytometry sorting. The CD4~+ CD25~+ Treg cells, however, obtained with both methods have similar immunosuppressive capacities. Conclusion: The result suggests that both methods can be used in isolating CD4~+ CD25~+ Treg cells, and one can select the best method according to specific needs and availability of the methodologies.  相似文献   
75.
Abstract

Exercise is recognized as a frontline therapy for the prevention and treatment of type 2 diabetes (T2D) but the optimal type of exercise is not yet determined. We compared the effects of high-intensity interval training (HIIT) with moderate-intensity continuous training (MICT) for improvement of continuous glucose monitoring (CGM)-derived markers of glycaemic variability, and biomarkers of endothelial cell damage (CD31+ and CD62+ endothelial microparticles (EMPs)) within a population at elevated risk of developing T2D. Fifteen inactive overweight or obese women were randomized to 2 weeks (10-sessions) of progressive HIIT (n?=?8, 4–10X 1-min @ 90% peak heart rate, 1-min rest periods) or MICT (n?=?7, 20–50?min of continuous activity at ~65% peak heart rate). Prior and three days post-training, fasting blood samples were collected. Both HIIT and MICT improved glycaemic variability as measured by CGM standard deviation (HIIT: 0.82?±?0.39 vs. 0.72?±?0.33?mmol/L; MICT: 0.82?±?0.19 vs. 0.62?±?0.16?mmol/L, pre vs. post) and mean amplitude of glycaemic excursions (MAGE; HIIT: 1.98?±?0.81 vs. 1.41?±?0.90; MICT; 1.98?±?0.43 vs. 1.65?±?0.48, pre vs. post) with no difference between groups. CD62+ EMPs were lower following HIIT (187.7?±?65 vs. 174.9?±?55, pre vs. post) and MICT (170?±?60 vs. 160.3?±?59, pre vs. post) with no difference between groups. There was no change in 24-h mean glucose or CD31+ EMPs. Two weeks of both HIIT or MICT similarly decreased glycaemic variability and CD62+ EMPs in overweight/obese women at elevated risk of T2D.  相似文献   
76.
运动训练对大鼠主动脉一氧化氮合酶及细胞凋亡的影响   总被引:2,自引:4,他引:2  
目的:探讨不同强度训练对大鼠主动脉一氧化氮合酶(NOS)及细胞凋亡的影响。方法:采用跑台训练方式,建立大鼠有氧运动和疲劳运动模型,运用免疫组织化学SABC法研究不同运动强度对大鼠主动脉神经型一氧化氮合酶(neuronal nitric oxide synthase,nNOS)、诱导型一氧化氮合酶(in-duced nitric oxide synthase,iNOS)、内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)和细胞凋亡蛋白(Bcl-2/Bax)表达的影响。结果:有氧训练组与对照组比较,主动脉NOS 3个亚型及Bcl-2,Bax表达差异显著(P<0.05);疲劳训练组与对照组和有氧训练组比较,主动脉iNOS、eNOS及Bcl-2,Bax表达差异显著(P<0.05),nNOS虽有增加但差异不显著。结论:运动可引起大鼠主动脉NOS 3个亚型及Bcl-2,Bax表达变化,且与运动强度关系密切。有氧训练可使主动脉NOS适度表达且抑制细胞凋亡,疲劳训练会导致大鼠主动脉iNOS过量表达,细胞发生凋亡现象。因此认为,运动训练引起NOS亚型表达变化与运动诱导的主动脉细胞凋亡关系密切。  相似文献   
77.
胃溃疡(Gu)、十二指肠溃疡(Du)和对照组(Con)各5例,取肉眼下非病变区胃窦粘膜,用免疫组织化学PAP双重染色法,在同一张切片上显示5-HT细胞和G细胞。结果5-HT细胞多散在于粘膜的中下1/3,呈棕褐色,形状多样,常见有突起的细胞。G细胞呈带状分布于粘膜的中1/3,大部分G细胞为蓝色,个别细胞为蓝黄混合色。它们多为圆形或锥体形。有时可见5-HT细胞和G细胞相毗邻。5-HT细胞数和G细胞数在Gu组分别为:4.17±1.21、7.87±3.13;Du组:5.45±1.96、9.21±5.72;Con组:3.21±1.64、6.19±1.72。5-HT细胞数和G细胞数在Gu组和Du组都增加。且都以Du组为最多,经相关分析二者呈正相关关系。Gu和Du组的5-HT细胞数和G细胞数与对照组相比均有高度显著性差异。Du组的5-HT细胞数和G细胞数与Gu组相比较,亦有高度显著性差异。提示5-HT细胞和G细胞可能参与了消化性溃疡病的调节,特别与Du的关系更为密切。5-HT细胞和G细胞之间的关系有待于进一步研究。  相似文献   
78.
用免疫组织化学 PAP 法,显示胰岛 B 细胞,观察大鼠生后发育期间全胰胰岛 B 细胞的形态、分布和数量变化。结果表明,B 细胞多呈园形或椭园形。B 细胞多位于胰岛中央,极少数 B 细胞位于胰腺外分泌部或导管上皮内。B 细胞百分数于1d 组最低,28d 组最高。结果提示,大鼠生后发育期间胰岛 B 细胞在继续发育。B 细胞具有其内胚层起源的形态学基础。  相似文献   
79.
目的探讨新生儿脐静脉血细胞的特点,为新生儿脐血细胞参考值调查及新生儿健康情况提供资料.方法用Sysmex K-4500全自动血细胞分析仪检测51例脐静脉血及50例成人静脉血,并作统计分析,性别间、组间比较采用均数的t检验.结果发现新生儿脐血细胞测定值不同于新生儿末梢血测定值,在男女间MCV、PLT差异有极显著性意义(P<0.01),RDW差异有显著性意义(P<0.05);此外,脐血细胞PDW、MPVR、及P-LCR在剖宫产组、胎吸组与顺产组的差异有极显著性意义(P<0.01).结论新生儿脐血细胞参数是一组特殊资料,反映了新生儿在宫内的发育状况,并与不同分娩方式有关.  相似文献   
80.
在EXCEL中使用VBA编程处理数据   总被引:4,自引:0,他引:4  
本文通过利用EXCEL中的VBA编写宏来自动生成全国等级考试机试安排表的实例 ,说明EXCEL中宏的应用和单元格引用的方法。  相似文献   
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