希—内学习能力测验在中国聋儿中使用的信度和效度

采用经部分修改的希－内学习能力测验（Ｈ－ＮＴＬＡ）量表对全国２１个省、市、自治区１７５８名３－１７岁聋儿逐人测试。样本人群地区分布、家长职业构成与１９９０年全国人口普查资料一致。１７５８名聋儿智商呈现正态分布（ｇ１＝０．０１１Ｐ＞０．０５，ｇ２＝０．０５８Ｐ＞０．０５）。测试员间信度系数０．９８１（Ｎ＝２４），复测信度０．８４１（Ｎ＝１３６），分半信度０．９２７（３－８岁）及０．８５４（９－１７岁）。各分测验得分随年龄增加而增加，小年龄组增加明显，大年龄组增加缓慢。各分测验之间、各分测验和总离差智商之间大多数相关系数有显著统计学意义。智商与学习成绩（语文及数学）相关系数０．２０８（Ｐ＜０．０１Ｎ＝２２４），与教师评语等级相关系数０．４４（Ｐ＜０．０５ｄｆ＝１６），表明经修订的Ｈ－ＮＴＬＡ量表适用于中国听力语言障碍人群进行智力评定。     

A computer-controlled whole-body inhalation exposure system for the oil dispersant COREXIT EC9500A

An automated whole-body inhalation exposure system capable of exposing 12 individually housed rats was designed to examine the potential adverse health effects of the oil dispersant COREXIT EC9500A, used extensively during the Deepwater Horizon oil spill. A computer-controlled syringe pump injected the COREXIT EC9500A into an atomizer where droplets and vapor were formed and mixed with diluent air. The aerosolized COREXIT EC9500A was passed into a customized exposure chamber where a calibrated light-scattering instrument estimated the real-time particle mass concentration of the aerosol in the chamber. Software feedback loops controlled the chamber aerosol concentration and pressure throughout each exposure. The particle size distribution of the dispersant aerosol was measured and shown to have a count median aerodynamic diameter of 285 nm with a geometric standard deviation of 1.7. The total chamber concentration (particulate + vapor) was determined using a modification of the acidified methylene blue spectrophotometric assay for anionic surfactants. Tests were conducted to show the effectiveness of closed loop control of chamber concentration and to verify chamber concentration homogeneity. Five automated 5-h animal exposures were performed that produced controlled and consistent COREXIT EC9500A concentrations (27.1 ± 2.9 mg/m(3), mean ± SD).     

ZAK is required for doxorubicin,a novel ribotoxic stressor,to induce SAPK activation and apoptosis in HaCaT cells

Doxorubicin is an anthracycline drug that is one of the most effective and widely used anticancer agents for the treatment of both hematologic and solid tumors. The stress-activated protein kinases (SAPKs) are frequently activated by a number of cancer chemotherapeutics. When phosphorylated, the SAPKs initiate a cascade that leads to the production of proinflammatory cytokines. Some inhibitors of protein synthesis, known as ribotoxic stressors, coordinately activate SAPKs and lead to apoptotic cell death. We demonstrate that doxorubicin effectively inhibits protein synthesis, activates SAPKs, and causes apoptosis. Ribotoxic stressors share a common mechanism in that they require ZAK, an upstream MAP3K, to activate the pro-apoptotic and proinflammatory signaling pathways that lie downstream of SAPKs. By employing siRNA mediated knockdown of ZAK or administration of sorafenib and nilotinib, kinase inhibitors that have a high affinity for ZAK, we provide evidence that ZAK is required for doxorubicin-induced proinflammatory and apoptotic responses in HaCaT cells, a pseudo-normal keratinocyte cell line, but not in HeLa cells, a cancerous cell line. ZAK has two different isoforms, ZAK-α (91 kDa) and ZAK-β (51 kDa). HaCaT or HeLa cells treated with doxorubicin and immunoblotted for ZAK displayed a progressive decrease in the ZAK-α band and the appearance of ZAK-β bands of larger size. Abrogation of these changes after exposure of cells to sorafenib and nilotinib suggests that these alterations occur following stimulation of ZAK. We suggest that ZAK inhibitors such as sorafenib or nilotinib may be effective when combined with doxorubicin to treat cancer patients.Key words: doxorubicin, ZAK, ribotoxic stressor, SAPKs, apoptosis     

The change in capacity and service delivery at public and private hospitals in Turkey: A closer look at regional differences

Background  

Substantial regional health inequalities have been shown to exist in Turkey for major health indicators. Turkish data on hospitals deserves a closer examination with a special emphasis on the regional differences in the context of the rapid privatization of the secondary or tertiary level health services.