Heteroepitaxy of Cerium Oxide Thin Films on Cu(111)

An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO₂ (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters.     

慢性活动性肝炎中单核性细胞超微形态研究

经电镜观察,慢活肝中主要为淋巴细胞及单核巨噬细胞浸润。淋巴细胞分3型,通过4种方式与肝细胞接触,可能代表杀伤肝细胞的动态过程。与肝细胞接触的主要为起细胞毒作用的T_8~+Ⅱ型淋巴细胞及单核巨噬细胞。多数T_4~+淋巴细胞为Ⅰ型淋巴细胞,可能为T辅助细胞。在肝细胞损伤中,淋巴细胞及单核巨噬细胞均起重要作用。     

A review of the effect of pesticide formulations on male fertility

Experimental studies suggest that large numbers of chemicals, environmental and industrial pollutants affect the male reproductive system. At present, almost no information is available on the effects of these adverse agents on human reproduction. Recent reports, however, suggest that in the past 50 years male fertility has declined based on qualitative and quantitative measurements of normal sperm. This study identifies‐among the active ingredients and solvents included in pesticide formulations registered in Italy‐the chemical agents with experimental evidence of male reproductive toxicity. Documents produced by international agencies and organizations such as IARC, EPA, WHO, and original papers from the international literature were systematically reviewed. The results indicate that several pesticide products notified in the Italian Registry contain active ingredients and/or solvents severely affecting testicular function and sperm morphology in laboratory animals. Therefore, exposure to reproductive toxicants occurring among manufacturers and users of pesticide formulations registered in Italy suggest further epidemiologic surveys should be conducted in this area.     

Evaluation of the Crithidia assay to distinguish between auto-immune chronic active hepatitis and systemic lupus erythematosus

The aim of this study was to determine if the Crithidia luciliae assay for auto-antibodies to double-stranded DNA, often positive in systemic lupus erythematosus, is always negative in auto-immune chronic active hepatitis (CAH) as has recently been suggested. Twenty-five patients were identified as having auto-immune CAH. Mean duration of follow-up was 10.5 years. Antinuclear antibodies were detected in 92%, smooth muscle antibodies in 76% and antimitochondrial antibodies in 16%. Antibodies to double-stranded DNA were detected by the Crithidia assay in four patients (16%). Two of these patients had positive tests on only one occasion and no features of systemic lupus erythematosus. In the other two the assay was persistently positive. During follow-up both developed arthritis and serositis but the liver lesion remained the dominant clinical feature. It was concluded that there is significant serological overlap between auto-immune CAH and systemic lupus erythematosus making the Crithidia assay unreliable in distinguishing between them.     

放免法检测乙型慢性活动性肝炎病人红细胞C3b受体的研究

用放免法检测乙型慢性活动性肝炎病人的红细胞ｃ３ｂ受体（ＫＢＣＣＲ１）．结果：病人ＲＢＣＣＲ１明显低于献血员（Ｐ＜０．０５）；抗－ＨＢｓ特异性免疫复合物阳性病人ＲＢＣＣＲ１明显低于阴性病人（Ｐ＜０．０１），与红细胞Ｃ３ｂ受体花环试验检测结果一致。表明乙型慢性活动性肝炎病人ＲＢＣＣＲ１数量减少，活性下降。其原因可能是特异性循环免疫复合物占据了ＲＢＣＣＲ１空位，使ＣＲ１活性下降。     

Undergraduate and postgraduate dental students''reflection on learning'': a qualitative study

The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described.     

新生儿重组酵母乙肝疫苗接种免疫的研究

目的：探讨重组酵母乙肝疫苗新生儿接种后抗体应答持续时间，强化复种的必要性。方法：常规对新生儿0d(出生后当天)、1月、6月接种重组酵母乙肝疫苗后检测抗体应答情况，再随机分两组，一组为强化组，一组为常规组，并随访其5年的抗体应答情况。结果：新生儿常规接种法，于12个月后有一明显抗体应答下降期(0d、1月、6月、12月)，强化组乙肝表面抗体形成率高，持续时间均高于常规接种法。结论：新生儿乙肝疫苗0d、1月、6月、12月接种法有较好的远期保护效果，对现有的0d、1月、6月新生儿乙肝疫苗常规接种法，有强化接种的必要。     

Implantation of Active Can Implantable Defibrillators in the right Pectoral Region

Routinely the active can ICD is placed in the left side pectoral position, which theoretically gives optimal conditions for a low defibrillation threshold. Some patients, bowever, demand a right pectoral position, which possibly could result in a bigger defibrillation threshold. A right pectoral position was used in 3 of 85 active can ICDs implanted in our institution from 1994. the DFT was 12 J in two and 18 f in one patient. Thus, right pectoral implantation is feasible and offers an alternative approach in selected patients.