中国大陆肺炎发病率与死亡率:1985-2008年中英文文献的系统分析

目的 肺炎是全球传染性疾病最主要的死因之一,但中国的肺炎疾病负担还知之甚少,因为很多数据资料都是以非英文文献的形式发表的.方法 系统回顾了中国大陆关于肺炎发病率与死亡率的中文和英文文献,这些研究都是具有第一手数据的研究,1985-2008年有37篇论文符合纳入标准.结果 各项研究的质量差异较大.5岁以下儿童肺炎发病率为(0.06～0.27)次/人年,肺炎死亡率为184/10万～1 223/10万人口.肺炎的发病率与死亡率随着时间稳定不变或者呈下降趋势,且农村高于城市.结论 肺炎仍然是中国儿童的主要公共卫生问题之一.肺炎发病率与死亡率估计的变化差异大.继续降低发病率与死亡率需要可靠的监测数据和新的预防措施的实施,特别是在农村等高发地区.     

Small Molecule Inhibitors of AI-2 Signaling in Bacteria: State-of-the-Art and Future Perspectives for Anti-Quorum Sensing Agents

Bacteria respond to different small molecules that are produced by other neighboring bacteria. These molecules, called autoinducers, are classified as intraspecies (i.e., molecules produced and perceived by the same bacterial species) or interspecies (molecules that are produced and sensed between different bacterial species). AI-2 has been proposed as an interspecies autoinducer and has been shown to regulate different bacterial physiology as well as affect virulence factor production and biofilm formation in some bacteria, including bacteria of clinical relevance. Several groups have embarked on the development of small molecules that could be used to perturb AI-2 signaling in bacteria, with the ultimate goal that these molecules could be used to inhibit bacterial virulence and biofilm formation. Additionally, these molecules have the potential to be used in synthetic biology applications whereby these small molecules are used as inputs to switch on and off AI-2 receptors. In this review, we highlight the state-of-the-art in the development of small molecules that perturb AI-2 signaling in bacteria and offer our perspective on the future development and applications of these classes of molecules.     

Core‐Brominated Tetraazaperopyrenes as n‐Channel Semiconductors for Organic Complementary Circuits on Flexible Substrates

Organic thin‐film transistors (TFTs) are prepared by vacuum deposition and solution shearing of 2,9‐bis(perfluoroalkyl)‐substituted tetraazaperopyrenes (TAPPs) with bromine substituents at the aromatic core. The TAPP derivatives are synthesized by reacting known unsubstituted TAPPs with bromine in fuming sulphuric acid, and their electrochemical properties are studied in detail by cyclic voltammetry and modelled with density functional theory (DFT) methods. Lowest unoccupied molecular orbital (LUMO) energies and electron affinities indicate that the core‐brominated TAPPs should exhibit n‐channel semiconducting properties. Current‐voltage characteristics of the TFTs established electron mobilities of up to μ_n = 0.032 cm² V^?1 s^?1 for a derivative which was subsequently processed in the fabrication of a complementary ring oscillator on a flexible plastic substrate (PEN).     

The influence of the microstructure of high noble gold-platinum dental alloys on their corrosion and biocompatibility in vitro

The aim of this work was to compare the microstructures of two high noble experimental Au-Pt alloys with similar composition with their corrosion and biocompatibility in vitro. We showed that Au-Pt II alloy, composed of 87.3 wt.% Au, 9.9 wt.% Pt, 1.7 wt.% Zn and 0.5 wt.% Ir + Rh + In, although possessing better mechanical properties than the Au-Pt I alloy (86.9 wt.% Au, 10.4 wt.% Pt, 1.5 wt.% Zn and 0.5 wt.% Ir + Rh + In), exerted higher adverse effects on the viability of L929 cells and the suppression of rat thymocyte functions, such as proliferation activity, the production of Interleukin-2 (IL-2), expression of IL-2 receptor and activation — induced apoptosis after stimulation of the cells with Concanavalin-A. These results correlated with the higher release of Zn ions in the culture medium. As Zn²⁺, at the concentrations which were detected in the alloy’s culture media, showed a lesser cytotoxic effect than the Au-Pt conditioning media, we concluded that Zn is probably not the only element responsible for alloy cytotoxicity. Microstructural characterization of the alloys, performed by means of scanning electron microscopy in addition to energy dispersive X-ray and X-ray diffraction analyses, showed that Au-Pt I is a two-phase alloy containing a dominant Au-rich α₁ phase and a minor Pt-rich α₂ phase. On the other hand, the Au-Pt II alloy additionally contained three minor phases: AuZn3, Pt₃Zn and Au_1.4Zn_0.52. The highest content of Zn was identified in the Pt₃Zn phase. After conditioning, the Pt₃Zn and AuZn₃ phases disappeared, suggesting that they are predominantly responsible for Zn loss, lower corrosion stability and subsequent lower biocompatibility of the Au-Pt II alloy.     

Attachment, separation, and women's vocational development: A longitudinal analysis.

This study tested a proposed model investigating the relations among attachment to and separation from parents, career self-efficacy, and career aspiration over a 5-year period with a sample of 207 young women. Results suggested that being attached to parents may lead to the development of confidence in pursuing career-related tasks, which in turn influences career aspiration. Separation from parents did not have direct effects on career self-efficacy. Results also indicated that women's career plans changed over a 5-year period with young women selecting more traditional and less prestigious careers than those to which they aspired in their senior year of high school. In addition, these women chose careers that underutilized their abilities. Finally, this sample of young women intended to have both careers and families, and the majority of these women ranked family as more important than career. (PsycINFO Database Record (c) 2010 APA, all rights reserved)