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991.
从脾论治磺脲类降糖药继发性失效   总被引:2,自引:0,他引:2  
对 64例 2型糖尿病继发磺脲类降糖药失效患者 ,在继续口服磺脲类药的基础上加用健脾中药 ,结果显效 1 5例 ,有效 3 6例 ,无效 1 3例 ,总有效率 85 .2 4% ;治疗前后血糖明显下降 ,有显著性差异 ( P<0 .0 0 1 )  相似文献   
992.
在体外试验中研究了azimexon对小鼠脾细胞增殖以及白细胞介素2(IL-2)的影响。IL-2活性采用小鼠胸腺细胞增殖法和CTLL细胞增殖法测定。结果表明:azimexon单独不能增加脾细胞增殖和产生IL-2,但对亚适量ConA或LPS诱导的脾细胞增殖和产生IL-2有明显协同作用。  相似文献   
993.
During myogenesis in Drosophila embryos, a prominent adhesive structure is formed between precursor cells and fusion-competent myoblasts (fcms). Here, we show that Duf/Kirre and its interaction partners Rols7 (found in founder myoblasts and growing myotubes) and Sns (found in fcms) are organized in a ring-structure at the contact points of fcms with precursor cells, while cytoskeletal components like F-actin and Titin are centered in this ring in both cell types. The cytoplasmic protein Blow colocalizes with the actin plugs in fcms after cell adhesion. Furthermore, the requirement of additional as yet unidentified components was demonstrated by using mammalian C2C12 myoblasts. In this study, we propose that the fusion-restricted myogenic-adhesive structure (FuRMAS) is pivotal in linking cell adhesion as well as local F-actin assembly and dynamics to downstream events that ultimately lead to plasma membrane fusion. Moreover, we suggest that the FuRMAS may restrict the area of membrane breakdown.  相似文献   
994.
目的 :探讨大鼠局灶性脑缺血再灌注损伤中bcl- 2及bcl-xl蛋白的表达。方法 :采用健康雄性大鼠大脑中动脉阻断 (MCAO)模型 ,阻断大脑中动脉 (MCA)血流 2h后再灌注 ,再灌注 0 .5h ,3h ,6h ,12h ,2 4h和 4 8h断头取脑后 ,进行bcl- 2、bcl-xl蛋白免疫组化染色。结果 :①Bcl- 2、Bcl-xl蛋白在脑缺血再灌注早期表达较强 ,3h - 6h达到高峰 ,2 4h~ 4 8h逐渐转阴。②bcl- 2及bcl-xl蛋白均分布在脑缺血梗死灶的周边 ,梗死中心区及正常区无表达。结论 :局灶性脑缺血再灌注损伤时 ,bcl- 2及bcl-xl表达对神经细胞的凋亡可能起着抑制作用  相似文献   
995.
丹参抗大鼠乙酸性十二指肠溃疡作用机制的探讨   总被引:2,自引:0,他引:2  
目的 探讨丹参抗大鼠乙酸性十二指肠溃疡的作用及机制。方法 按Okabe方法复制大鼠乙酸十二指肠溃疡模型 ,按传统方法测定溃疡指数、溃疡抑制率 ;用放射免疫法测定十二指肠溃疡部位的前列腺环素 (PGI2 )含量。结果 丹参组的溃疡指数显著低于对照组 (P <0 .0 1) ,其溃疡抑制率高于对照组 ,PGI2 的含量亦显著高于对照组 (P <0 .0 1)。结论 丹参具有抗大鼠十二指肠溃疡的作用 ,其机制可能是丹参提高了十二指肠粘膜的防御能力  相似文献   
996.
AIMS: Scarcity of resources, expertise and evidence-based models have so far limited delivery of patient-centred diabetes education. We have developed and validated a group care approach that is applicable to everyday clinical practice and cost-effective in improving metabolic control, knowledge of diabetes, health behaviours, and quality of life in Type 2 diabetes. A clinical trial (ROMEO) was planned to evaluate applicability and reproducibility of group care in other outpatients facilities and assess its impact on a larger patient population. METHODS: Multicentre, randomized, controlled clinical trial of group vs. individual care in the routine management of Type 2 diabetes. Nine hundred patient aged < 80, with diabetes of > or =1 year known duration, treated by either diet alone or diet and oral agents, will be recruited in 15 centres and followed for 4 years. Training of physicians, nurses and dietitians included preparation of operating manual and videos, interactive sessions, and evaluation of local facilities and resources. RESULTS: Primary measurements: 3-monthly HbA1c, fasting blood glucose, body weight, waist-hip ratio, yearly blood lipids, and bi-yearly assessment of knowledge of diabetes, health behaviours and quality of life. Secondary outcomes: systolic and diastolic blood pressure, evaluation of ECG for ischaemia and QT interval, hypoglycaemic and anti-hypertensive medication and cardiovascular events. Analysis will be by intention-to-treat. DISCUSSION: If ROMEO confirms that group care can be successfully implemented in different clinics, a novel clinico-pedagogic tool will have been acquired to support patient-centred education, improve lifestyle and outcomes, support team work, enhance providers' attitudes and competencies and ameliorate diabetes care organization.  相似文献   
997.
目的:观察三氧化二砷(As2O3)和全反式维甲酸(ATRA)联合作用对NB4,MR2不同亚型急性早幼粒白血病细胞株,诱导分化、增殖、凋亡的影响。方法:以NB4,MR2为体外模型,利用细胞生长曲线、台盼蓝拒染法、MTT法、NBT、细胞形态Wrigh‘s-Gimesa染色,观察细胞增殖、分化、凋亡的相互作用。结果:NB4细胞株:0.5μmol/L As2O3与10^-6mol/L ATRA对细胞增殖、分化、凋亡呈现拮抗,而0.5μmol/L As2O3与(10^-7--10^-8mol/L)ATRA呈现协同;MR2细胞株:0.5μmol/L As2O3与10^-6mol/L ATRA对细胞增殖、分化、凋亡呈现协同。结论:As2O3与全反式维甲酸协同效应呈现不同细胞、剂量的特异性,MR2细胞株协同效应明显强于NB4细胞株。  相似文献   
998.
心肌缺血再灌注损伤时细胞核被膜钙泵活性特征的研究   总被引:1,自引:0,他引:1  
目的 研究心肌缺血再灌注损伤时Ca2 + 、ATP、ADP和AMP对细胞核被膜钙泵 (Ca2 + ATPase)活性的调节。方法 采用大鼠心肌缺血再灌注模型 ,密度梯度分离纯化细胞核 ,定磷法测定Ca2 + ATPase活性。结果 与正常大鼠相比 ,缺血再灌注损伤动物血浆MDA和FFA显著升高 (P <0 0 1) ;细胞核Ca2 + ATPase活性下降 ,对Ca2 + 亲和力降低 ;ADP、AMP对核Ca2 + ATPase活性的影响明显减弱 ;ATP对Ca2 + ATPase的作用在 [ATP]小于 1 0mmol L时 ,与正常细胞Ca2 + AT Pase活性无显著差异 ,浓度增至 2 0mmol L时 ,活性低于正常细胞 ,ATP浓度继续增加 ,核Ca2 + ATPase活性快速增加。结论 心肌缺血再灌注损伤时Ca2 + 、ATP、ADP、AMP对心肌细胞核Ca2 + ATPase活性的影响发生了明显改变 ,其病理生理意义值得进一步探讨。  相似文献   
999.
BACKGROUND: Asymmetrical dimethylarginine (ADMA) is capable of inhibiting nitric oxide synthase enzymes, whereas symmetrical dimethylarginine (SDMA) competes with arginine transport. The potential role of inflammation in the metabolism of ADMA has been elucidated in an in vitro model using tumour necrosis factor-alpha, resulting in a decreased activity of the ADMA-degrading enzyme dimethylarginine dimethylaminohydrolase (DDAH). The kidney probably plays a crucial role in the metabolism of ADMA by both urinary excretion and degradation by DDAH. We aimed to further elucidate the role of the kidney in a rat model under basal conditions and during endotoxaemia. METHODS: Twenty-five male Wistar rats weighing 275-300 g were used for this study. The combination of arteriovenous concentration differences and kidney blood flow allowed calculation of net organ fluxes. Blood flow was measured using radiolabelled microspheres according to the reference sample method. Concentrations of ADMA, SDMA and arginine were measured by high-performance liquid chromatography. RESULTS: The kidney showed net uptake of both ADMA and SDMA and fractional extraction rates were 35% and 31%, respectively. Endotoxaemia resulted in a lower systemic ADMA concentration (P = 0.01), which was not explained by an increased net renal uptake. Systemic SDMA concentrations increased during endotoxaemia (P = 0.007), which was accompanied by increased creatinine concentrations. CONCLUSIONS: The rat kidney plays a crucial role in the regulation of concentrations of dimethylarginines, as both ADMA and SDMA were eliminated from the systemic circulation in substantial amounts. Furthermore, evidence for the role of endotoxaemia in the metabolism of dimethylarginines was obtained as plasma levels of ADMA were significantly lower in endotoxaemic rats.  相似文献   
1000.
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