7-甲氧基-4′-羟基-3′-二乙胺甲基异黄酮(MHDF)对大鼠血流动力学和主动脉的作用

本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3～12.8 mg/kg)能降低大鼠左心室±dp/dt_max,V_max,V_pm和LVSP,延长T-dp/dt_max,减慢心率。MHDF还能舒张大鼠胸主动脉,ED₅₀为6.5×10^-6mol/L;非竞争拮抗NA和CaCl₂致主脉收缩,pD₂′为3.11±0.21和3.73±0.07;抑制高K⁺致主动脉收缩,IC₅₀为1.76×10^-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。     

Expression of HIF-1 and ubiquitin in conventional renal cell carcinoma: relationship to mutations of the von Hippel-Lindau tumor suppressor gene

Conventional clear cell renal cell carcinomas (cRCC) have mutations of the von Hippel-Lindau (VHL) tumor suppressor gene at 3p25 in approximately 50% of cases. The VHL gene normally regulates ubiquitin-mediated proteolysis of hypoxia-inducible factor 1alpha (HIF-1alpha); in cell lines, VHL inactivation blocks HIF-1alpha proteolysis, resulting in increased HIF-1 expression. This study was undertaken to investigate the relationship between VHL mutations and the expression of ubiquitin and HIF-1alpha in cRCC. Eleven cRCC were studied with microsatellite analysis for 3p deletions and with sequencing for VHL mutations. Immunohistochemistry was performed for HIF-1alpha and ubiquitin. Deletions at 3p25 were found in 10 tumors, and VHL mutations were identified in 6 of these cases. There was staining for ubiquitin and HIF-1alpha in all tumors with VHL mutations. Among the five cases without VHL mutations, staining for ubiquitin or HIF-1alpha was not present in three cases but was present in two tumors, both of which had 3p deletions. The findings support a role for VHL mutations promoting cRCC development by an impairment of HIF-1alpha proteolysis. The findings also suggest that a 3p tumor suppressor gene other than VHL may also influence HIF-1alpha degradation and that there is an additional tumorigenic pathway for cRCC that does not involve VHL or HIF-1.     

Beckman EL-ISE电解质分析仪准确性及故障的分析判断

0 引言为了克服离子选择电极（ISE）法的微量电位信号极易受环境温度变化及电子噪声的干扰问题,该仪器采用了参考电极,把参考电极与其测定电极装在同一测量室内,保持其相同的物理环境,使干扰源对所有电极的影响相同. 以内参液作为参考电极的测量对象,测得一个参考电极电位值,再测样品的电极电位值,二者相抵就消除了所叠加的干扰信号.     

心脏直视手术围术期自体血回输335例的监护

0　引言　自体输血是采集患者体内血或回收自体失血,再输回同一患者,献血者与受血者为同一个体,既可以节约临床用血,减少患者费用,更重要是可以避免或减少同种输血传播感染性疾病.我科对335例体外循环心内直视手术患者实行自体血回输,收到较好的社会效益和经济效益.1　临床资料　1998-09/1999-02,我科心脏直视手术共445例,围术期采用自体输血335例,其中先心病226例,瓣膜手术59例,复杂心内畸形37例,冠心病、大血管13例,占同期体外循环心内直视手术75%.患者主要适应证:心脏及大血管外科手术,术前一般情况尚好,无肝、肾、呼吸功能障碍;术前检查…     

Cervical carcinoma with adenoid cystic pattern: a light and electron microscopic study.

Three cases of cervical carcinoma with an adenoid cystic pattern were studied by light and electron microscopy. All were found to be compatible with the histologic picture of adenoid cystic carcinoma in other body sites. Although there was some variability in the pattern among the tumors, areas of each exhibited a cribriform appearance characterized by small cells with sparse cytoplasm arranged around cystic gland-like lumina. Only one tumor displayed cylindromatous formations similar to those described by Billroth. Two of the tumors were associated with foci of squamous cell carcinoma while the third contained areas suggestive of such a component. Electron microscopic examination showed varied morphology of the cysts, manifested by true glandlike lumina, extracellular spaces containing replicated basement membrane or enclosed stroma. In view of the observed diversity in the light and electron microscopic morphology of adenoid cystic carcinomas of the cervix, it is apparent that this tumor is not a distinct histologic entity. Accordingly, it is recommended that the terminology "cervical carcinoma with adenoid cystic pattern" be utilized.