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31.
This article presents a leadership-based intervention model designed to modify supervisory monitoring and rewarding of subordinates' safety performance. Line supervisors received weekly feedback based on repeated episodic interviews with subordinates concerning the cumulative frequency of their safety-oriented interactions. This information identified the priority of safety over competing goals such as speed or schedules. Section managers received the same information and used it to communicate (high) safety priority. They also were trained to conduct episodic interviews to provide intermittent feedback after intervention, turning safety priority into an explicit performance goal. Safety-oriented interaction increased significantly in the experimental groups but remained unchanged in the control groups. This change in safety-oriented interaction was accompanied by significant (and stable) changes in minor injury rate, earplug use, and safety climate scores during the postintervention period. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Rubinstein-Taybi syndrome (RSTS) is a rare condition with a prevalence of 1 in 125,000–720,000 births and characterized by clinical features that include facial, dental, and limb dysmorphology and growth retardation. Most cases of RSTS occur sporadically and are caused by de novo mutations. Cytogenetic or molecular abnormalities are detected in only 55% of RSTS cases. Previous genetic studies have yielded inconsistent results due to the variety of methods used for genetic analysis. The purpose of this study was to use whole exome sequencing (WES) to evaluate the genetic causes of RSTS in a young girl presenting with an Autism phenotype. We used the Autism diagnostic observation schedule (ADOS) and Autism diagnostic interview revised (ADI-R) to confirm her diagnosis of Autism. In addition, various questionnaires were used to evaluate other psychiatric features. We used WES to analyze the DNA sequences of the patient and her parents and to search for de novo variants. The patient showed all the typical features of Autism, WES revealed a de novo frameshift mutation in CREBBP and de novo sequence variants in TNC and IGFALS genes. Mutations in the CREBBP gene have been extensively reported in RSTS patients, while potential missense mutations in TNC and IGFALS genes have not previously been associated with RSTS. The TNC and IGFALS genes are involved in central nervous system development and growth. It is possible for patients with RSTS to have additional de novo variants that could account for previously unexplained phenotypes.  相似文献   
33.
Channel catfish (Ictalurus punctatus) is an important agricultural fish that has been plagued by Streptococcus iniae (S. iniae) infections in recent years, some of them severe. C5a peptidase is an important virulent factor of S. iniae. In this study, the subunit vaccine containing the truncated part of C5a peptidase (pSCPI) was mixed with aluminum hydroxide gel (AH), propolis adjuvant (PA), and Freund’s Incomplete Adjuvant (FIA). The immunogenicity of the pSCPI was detected by Western-blot in vitro. The relative percent survival (RPS), lysozyme activity, antibody titers, and the expression of the related immune genes were monitored in vivo to evaluate the immune effects of the three different adjuvants. The results showed that pSCPI exerted moderate immune protection (RPS = 46.43%), whereas each of the three adjuvants improved the immune protection of pSCPI. The immunoprotection of pSCPI + AH, pSCPI + PA, and pSCPI + FIA was characterized by RPS values of 67.86%, 75.00% and, 85.71%, respectively. Further, each of the three different adjuvanted pSCPIs stimulated higher levels of lysozyme activity and antibody titers than the unadjuvanted pSCPI and/or PBS buffer. In addition, pSCPI + FIA and pSCPI + PA induced expression of the related immune genes under investigation, which was substantially higher than the levels stimulated by PBS. pSCPI + AH significantly stimulated the induction of MHC II β, CD4-L2, and IFN-γ, while it induced slightly higher production of TNF-α and even led to a decrease in the levels of IL-1β, MHC I α, and CD8 α. Therefore, we conclude that compared with the other two adjuvants, FIA combined with pSCPI is a more promising candidate adjuvant against S. iniae in channel catfish.  相似文献   
34.
ATP合酶,又称F1F0-ATP合成酶,是位于线粒体内膜、叶绿体类囊体膜和光合菌质膜上的参与呼吸链氧化磷酸化的最后环节。其结构包含F1和F0两个亚单位,共同作用于ATP的分解和合成。ATP合酶β亚基是F1F0-ATP合成酶F1亚单位的重要组件,该亚基包含ATP合成和水解所需的催化位点,其功能好坏与疾病发生直接相关。本文就ATP合酶β亚基功能与糖尿病、肿瘤、肥胖症等疾病的关系作一综述。  相似文献   
35.
目的构建乙酰肝素酶(HPA)大亚基片段真核表达质粒,并在毕赤酵母中表达重组蛋白。方法根据GenBank中登录的HPA大亚基基因序列设计引物,PCR方法扩增肝素酶基因,构建毕赤酵母真核表达质粒pPICZαA-HPA。电击穿孔法转化感受态毕赤酵母SDM1168,斑点免疫印迹法筛选重组菌株,PCR法鉴定阳性克隆。甲醇诱导表达重组蛋白,Western blot鉴定表达产物。结果构建的重组真核表达质粒经双酶切及测序鉴定证明构建正确;斑点免疫印迹法筛选出的9个单菌落经PCR扩增,均可见1161bp的目的基因条带;表达产物经Western blot分析,具有良好的反应原性,表达量约为5μg/L。结论已成功构建了HPA大亚基片段真核表达质粒pPICZαA-HPA,并在毕赤酵母SDM1168中分泌表达了HPA大亚基。  相似文献   
36.
分析了高分子量谷蛋白亚基近等基因系的高分子量谷蛋白亚基组成,并对该近等基因系进行了品质性状的分析,结果表明:Glu-D1位点的变化比Glu-B1位点的变化对面粉品质和流变学特性影响大;并且同时具有Glu-B1 14 15和Glu-D1 5 10的近等基因系2号无论是面粉品质还是流变学特性都优于其它两个近等基因系8号(null,7 9,5 10)和近等基因系13号(null,14 15,10);而8号又优于13号,即Glu-B1 14 15的存在没有弥补Glu-D1 5亚基的缺失。  相似文献   
37.
38.
Han-Cheol Choe 《Thin solid films》2011,519(15):4652-4657
The nanotubular surface of Ti-binary and Ti-ternary alloys for biomaterials has been investigated using various methods of surface characterization. Binary Ti-xNb (x = 10, 20, 30, and 40 wt.%) and ternary Ti-30Ta-xNb (x = 3, 7 and 15 wt.%) alloys were prepared by using the high-purity sponges; Ti, Ta and Zr spheres. The nanotube on the alloy surface was formed in 1.0 M H3PO4 with small additions of NaF (0.5 and 0.8 wt.%), using a potentiostat. For cell proliferation, an MC3T3-E1 mouse osteoblast was used. The surface characteristics were investigated using field-emission scanning electron microscope, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy.Binary Ti-xZr alloys had a lamellar and a needle-like structure, whereas, ternary Ti-30Ta-xZr alloys had equiaxed grains with a lamellar martensitic α′ structure. The thickness of the needle-like laths of the α-phase increased as the Zr content increased. The nanotubes formed on the α phase and β phase showed a different size and shape appearance with Zr content. As the Zr content increased from 3 to 40 wt.%, the diameter of the nanotubes in Ti-xZr and Ti-30Ta-xZr alloy decreased from 200 nm to 50 nm. The nanotubular Ti-30Ta-15Zr alloy surface with a diameter of 50 nm provided a good osseointegration; cell proliferation, migration and differentiation.  相似文献   
39.
近液相线铸造过程中近球形α相的形成机理   总被引:2,自引:0,他引:2  
为从理论上弄清近液相线半连续铸造过程中铝合金半固态组织形成的基本规律和机制,研究了浇注温度、铸造速度和冷却强度等工艺参数对6061合金初生α相演变的影响,根据金相检测和多尺度计算机模拟结果,分析了近球形α相的形成机理.实验发现,在浇注温度为657℃、铸造速度为150 mm/min、冷却水流量为0.05 m3/min时可...  相似文献   
40.
Pyruvate carboxylase (PC) is a critical enzyme in supplying carbon for gluconeogenesis and oxaloacetate for the tricarboxylic acid cycle. The bovine PC (EC 6.4.1.1) gene contains 3 promoter sequences (P3, P2, and P1 from 5′ to 3′). Physiological stressors, including the onset of calving and feed restriction, lead to elevated nonesterified fatty acids and glucocorticoid levels that coincide with an increase in PC mRNA expression. The effects of elevated fatty acids on bovine PC mRNA expression and promoter function have not been determined. The objective of this experiment was to determine the direct effects of stearic, oleic, and linoleic acids, dexamethasone, and Wy14643 (a peroxisome proliferator-activated receptor-α agonist) on bovine PC promoter activity. Promoter-luciferase constructs, containing 1,005 bp of P1, 1,079 bp of P2, or 1,010 bp of P3, were transiently transfected into rat hepatoma (H4IIE) cells. Cells were then treated with 1 mM stearic, oleic, or linoleic acids, 1 μM dexamethasone, or 10 μM Wy14643 for 23 h. Activity of P1 was suppressed with exposure to stearic acid (1.58 vs. 6.19 ± 0.81 arbitrary units for stearic vs. control, respectively) and enhanced with exposure to Wy14643 (9.26 vs. 6.19 ± 0.81 arbitrary units for Wy14643 vs. control, respectively). Conversely, stearic acid enhanced P3 activity (2.55 vs. 0.40 ± 0.33 arbitrary units for stearic vs. control, respectively). Dexamethasone, linoleic acid, and oleic acid failed to elicit a response from any of the promoters tested. These data demonstrate the direct role of fatty acids in regulating PC expression and indicate that fatty acids provide promoter-specific regulation of PC promoters.  相似文献   
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