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81.
目的:观察核心结合因子a1(Cbfa1)对兔骨髓间充质干细胞(MSCs)向成骨细胞分化的诱导作用。方法:体外分离培养兔骨髓MSCs,用AdEasy1/Cbfa1。转染MSCs,在转染后3d,1、2、3和4周时,组织化学和免疫组化等方法检测成骨标志碱性磷酸酶和骨钙素的表达。结果:AdEasy1/Cbfa1转染后的兔骨髓MSCs表现出与成骨细胞相似的形态,并且表达碱性磷酸酶和骨钙素。结论:Cbfa1可诱导兔骨髓MSCs向成骨细胞分化。 相似文献
82.
Kazuyoshi Kataoka Katsuo Furukawa Kohichi Nagao Nobuhisa Ishii Hiromichi Tsuru 《International journal of urology》2007,14(8):764-768
AIM: To investigate the participation of adenosine receptors in the adenosine 5'-triphosphate (ATP)-induced relaxation in the corpus cavernosum penis (CCP) of rabbits. METHODS: The ATP-induced relaxation was assessed on the noradrenaline precontracted CCP of rabbits in the presence and absence of 8-(3-chlorostyryl)caffeine (CSC); an adenosine A(2A) receptor antagonist; alloxazine and MRS1754; adenosine A(2B) receptor antagonists; and ARL67156, an inhibitor of ecto-nucleoside triphosphate diphosphohydrolases. RESULTS: Adenosine and ATP relaxed the noradrenaline precontracted CCP of rabbits in a concentration-dependent manner. The adenosine- and ATP-induced relaxations were suppressed by alloxazine and MRS1754, but not by 8-(3-chlorostyryl)caffeine. ARL67156 potentiated the ATP-induced relaxation but not the adenosine-induced one. MRS1754 suppressed the ATP-induced relaxation potentiated by ARL67156. CONCLUSIONS: The above results suggest that, in the CCP of rabbits, the adenosine receptor mediating adenosine-induced relaxation is of the A(2B) receptor and the ATP directly causes relaxation through the A(2B) receptor on the CCP. 相似文献
83.
84.
云南省600例0~5岁儿童维生素A缺乏调查 总被引:3,自引:3,他引:0
目的:了解云南省城乡0~5岁儿童维生素A营养状况及影响因素。方法:省、地、县随机整群抽取600例儿童,采用微量荧光光度法检测VitA含量。结果:VitA缺乏发生率16·17%,地、县明显高于省会城市;0岁儿童明显高于其他年龄组;腹泻儿童明显高于正常儿童;VitA缺乏的影响因素:近1周内进食鸡蛋、奶类制品、鱼虾类、肝类、黄绿色蔬菜、鱼肝油等食物有利于维生素A的吸收,急性呼吸道感染、发烧与维生素A缺乏发生率差异不明显。结论:维生素A缺乏发生率城市明显低于农村地、县两级,说明维生素A缺乏防治工作重点在农村,特别是0岁儿童,防治的主要措施是采取合理膳食,均衡营养,控制腹泻流行。 相似文献
85.
F Celi V Bini F Papi E Santilli M S Castellani A Ferretti M Mencacci M G Berioli G De Giorgi A Falorni 《Diabetic medicine》2006,23(6):660-665
AIM: To determine the influence of Type 1 diabetes mellitus on circulating adipocytokines in children. METHODS: The circulating concentrations of leptin, adiponectin, resistin and tumour necrosis factor (TNF)-alpha were measured in 91 children, aged 11.1 +/- 2.7 years, with Type 1 diabetes mellitus (T1DM). Ninety-one healthy children were selected as control subjects. RESULTS: Body mass index-adjusted leptin concentrations were higher in the pubertal diabetic children compared with the control children. There was a significant positive correlation between leptin and daily insulin dose in the diabetic group. Circulating adiponectin concentrations were higher in the prepubertal diabetic children and were positively associated with HbA(1c). Resistin concentrations were lower in the prepubertal non-diabetic subjects compared with the pubertal non-diabetic children, whose values were higher than those of the diabetic children. TNF-alpha concentrations were similar in non-diabetic and diabetic children. CONCLUSIONS: Circulating concentrations of adipocytokines are abnormal in Type 1 diabetic children, although the direction of change differs by cytokine. Pubertal development, in addition to insulin treatment and glycaemic control, also influences the concentrations. 相似文献
86.
87.
88.
特异性荧光偏振免疫法监测521例肾移植后环孢素A全血浓度3275次 总被引:2,自引:0,他引:2
目的通过监测肾移植后病人环孢素A(CsA)全血浓度 ,提出CsA在三联免疫抑制用药方案中的理想治疗窗。方法用特异性荧光偏振免疫法测定CsA全血浓度 ,对521例病人监测3275次 ,按术后时间及临床表现分组比较。结果肾移植后<1 ,、1~3、3~6、6~12个月、1~2和>2年的CsA全血谷浓度的理想治疗窗应分别为250~450、200~400、150~300、100~250、100~200和100~180μg/L。结论CsA全血浓度在上述范围内 ,中毒反应和排异反应明显减少 相似文献
89.
The discovery of an inducible isoform of cyclooxygenase (COX-2) requires a refinement of the theory that inhibition of cyclooxygenase
activity is responsible for both therapeutic and side-effects of nonsteroidal anti-inflammatory drugs (NSAIDs). Pharmacological
results with developmental compounds suggest that COX-2 is the relevant target for the therapeutic (i.e. anti-inflammatory)
effects of NSAIDs, whereas gastric and renal side-effects are related to inhibition of constitutive COX-1. However a role
of COX-1 in inflammation cannot be excluded. Furthermore, more research effort is needed to investigate the functional relevance
of COX-2 in normal tissue. 相似文献
90.
Sinusoids are found not only in the normal liver but also in certain liver tumours, including hepatoblastoma, the most common malignant liver tumour in childhood. In this study, sinusoids in 12 hepatoblastomas, of various subtypes, and in normal liver were investigated with UEA-1 and antibodies against von Willebrand's factor, CD31 and CD34 to detect differences of possible diagnostic significance. In the normal liver, staining of sinusoids was seen with all these markers, but it was focal and confined to a few sinusoids near the portal tracts. In hepatoblastoma, the endothelial markers reacted with the sinusoids to varying extents. UEA-1 and anti-CD34 usually stained the majority of these vessels, anti-CD34 staining greater numbers of sinusoids and with greater intensity. Immunostaining revealed that both number and spatial organization of sinusoids in hepatoblastoma are dependent on the subtype. In addition to staining of endothelium, one of the two small cell hepatoblastomas exhibited strong immunoreactivity of the tumour cells for CD34. These findings show that the marked difference in sinusoidal immunoreactivity for CD34 between normal liver and hepatoblastoma could be useful for discriminating between non-neoplastic liver tissue and highly differentiated fetal hepatoblastoma. Our findings also show that small cell hepatoblastoma, in addition to acute leukaemia, should be considered when immunoreactivity for CD34 is found in small round and blue cell tumours in childhood. 相似文献