Brief Report: Eye Movements During Visual Search Tasks Indicate Enhanced Stimulus Discriminability in Subjects with PDD

Subjects with PDD excel on certain visuo-spatial tasks, amongst which visual search tasks, and this has been attributed to enhanced perceptual discrimination. However, an alternative explanation is that subjects with PDD show a different, more effective search strategy. The present study aimed to test both hypotheses, by measuring eye movements during visual search tasks in high functioning adult men with PDD and a control group. Subjects with PDD were significantly faster than controls in these tasks, replicating earlier findings in children. Eye movement data showed that subjects with PDD made fewer eye movements than controls. No evidence was found for a different search strategy between the groups. The data indicate an enhanced ability to discriminate between stimulus elements in PDD.     

Marihuana and retrieval from short-term memory

Twelve subjects received an oral dose of marihuana extract calibrated to 20 mg of ¹-tetrahydrocannibinol on Day 1 of the experiment and performed a short-term memory task before and after administration of the drug. The subjects were then split into two groups, receiving either marihuana or placebo on the evenings of Days 1 to 4 and between two memory test sessions on Day 5. Placebo subjects showed little change in performance between the two test sessions on Day 5; however, results from Day 1 for all subjects and Day 5 for the drug group showed that reaction time increased from before- to after-challenge sessions. This increase in time under marihuana was explained as a change in encoding and/or response processes, rather than processes involved in the search of the memory store.This research was supported by grants MH-03030 and MH-19918-02 from the National Institute of Mental Health and a grant from the Van Ameringen Foundation. The authors thank Pat Murphy for her assistance in collecting data.     

PubMed新的检索工具--NCBI Search Toolbar及其应用

NCBI Search Toolbar是美国国立医学图书馆（NLM）新近推出的专用搜索工具,本文介绍该工具的特点、使用方法等.     

基于Internet的生物信息资源快速查找与利用

生物信息学是现代生命科学与信息科学、计算机科学、数学、统计学、物理学、化学等学科相互渗透而高度交叉形成的一门新兴前沿学科.生命科学的所有信息均可由计算机和因特网来进行储存、分析和传输.因特网为我们提供了大量的有关生物信息相关的数据、工具、文献、软件等资源.本文根据笔者的实践经验,对因特网上生物信息资源进行了整理和分类,总结了因特网上获取生物信息资源的途径及其利用,介绍了一些快速查找方法与技巧,以便读者更迅速更准确利用因特网上生物信息资源.     

用层次分析法定量评价综合性搜索引擎

利用层次分析法计算各层指标的权重,并用相对查准率等方法对最底层评价指标进行评分,最后综合权重和最底层评价指标的得分,定量评价Google,YAHOO,Baidu,SOHU4个综合性搜索引擎。结果表明,运用层次分析法定量评价搜索引擎的综合水平具有较强的科学性。     

搜索引擎的个性化发展趋势

 

从用户需求和搜索引擎市场竞争两个方面论述了搜索引擎个性化发展的背景及个性化的内涵，重点分析近年来国内外搜索引擎推出的个性化搜索和个性化服务及其发展趋势。

     

贵州省2004年流行性乙型脑炎监测与控制策略探讨

目的通过对贵州省2004年流行性乙型脑炎(乙脑)监测及高发地区预防接种的实施,分析乙脑流行状况,并探讨控制策略。方法对疫情信息监测管理系统信息、个案调查资料、实验室结果进行分析;在4个乙脑高发地区,对≤10岁儿童接种乙脑疫苗并进行综合分析。结果2004年共报告乙脑1 230例,≤10岁病例占总病例数的86.59%(1 065/1 230)。男女性发病比例为1.58∶1;全年除1月外均有报告病例,主要集中7~9月;遵义市、毕节地区、黔东南苗族侗族自治州、黔西南布依族苗族自治州乙脑病例数占全省总病例数的65.85%(810/1 230)。有免疫史的占6.90%(26/377),无免疫史和免疫史不详的占93.10%(351/377)。实验室检测乙脑IgM抗体阳性率为74.90%(188/251),实验室诊断病例数占总病例数的15.28%。与2003年比较乙脑发病下降29.80%。结论建立并提高乙脑监测及实验室血清学诊断水平,实施乙脑疫苗预防接种为主的综合防治措施,尤其对高发地区的≤10岁儿童开展乙脑疫苗预防接种,进一步降低乙脑发病率。     

A new module for on-line manipulation and display of molecular information in the brain architecture management system

A new “Molecules” module of the Brain Architecture Management System (BAMS; http://brancusi.usc.edu/bkms) is described. With this module, BAMS becomes the first online know ledge management system to handle central nervous system (CNS) region and celltype chemoarchitectonic data in the context of axonal connections between regions and cell types, in multiple species. The “Molecules” module implements a general knowledge representation schema for data and metadata collated from published and unpublished material, and allows insertion of complex reports about the presence of molecules collated from the literature. For different CNS neural regions and cell types the module's database structure includes representation of molecule expression revealed by various techniques including in situ hybridization and immunohistochemistry, molecule coexpression and time-dependent level changes, and physiological state of subjects. The metadata representation allows online comparison and evaluation of inserted experiments, and “Molecules” structure allows rapid development of data transfer protocols enabling neuroinformatics visualization tools to display gene expression patterns residing in BAMS, in terms of levels of expressed molecules and in situ hybridization data. The module's web interface allows users to construct lists of CNS regions containing a molecule (depending on physiological state), retrieve further details about inserted records, compare time-dependent data within and across experiments, reconstruct gene expression patterns and construct complex reports from individual experiments.     

Limited search strategies were effective in finding relevant nonrandomized studies

BACKGROUND AND OBJECTIVE: Searching for nonrandomized studies in electronic databases is complicated because there is a variety of study designs and lack of standardization in the terminology. The purpose of this study was to develop and evaluate a method to limit search strategies according to study design of comparative nonrandomized studies (cNRSs). METHODS: Four updated Cochrane systematic reviews that included nonrandomized studies (cohort, case-control, and cross-sectional studies) of the effects of health care interventions were selected. Search strategies limited to study design were devised for each one of these topic areas in two electronic databases (MEDLINE and EMBASE). A progressive method (PM) and a fixed method for selecting the most appropriate search terms associated with study design of nonrandomized studies are suggested. RESULTS: The results showed that the sensitivity of search strategies (in two databases combined) limited to study design were between 90% and 100% for the PM using both controlled vocabulary (CV) and textwords (TWs) and between 95% and 100% for a fixed set of controlled vocabulary and TWs. CONCLUSIONS: It is possible and acceptable to use search strategies limited to study design of cNRSs of health care interventions.     

Roads, railways, and childhood cancers

Study OBJECTIVES: To locate geographical sources of engine exhaust emissions in Great Britain and to link them with the birth addresses of children dying from cancer. To estimate the cancer initiating roles of nearby roads and railways and to measure effective ranges. DESIGN: Birth and death addresses of all children born between 1955 and 1980 in Great Britain, and dying from leukaemia or other cancer during those years, were linked to locations of railway stations, bus stations, ferry terminals, railways, roads, canals, and rivers. Nearest distances to births and deaths were measured, and migration data relating to children who had moved house were analysed. Excesses of close to hazard birth addresses, compared with close to hazard death addresses, indicate a high prenatal or early postnatal risk of cancer initiation. SETTING AND SUBJECTS: Child cancer birth and death addresses and their map references were extracted from an earlier inquiry. Map references of putative hazards were downloaded from the Ordnance Survey national digital map of Great Britain. These data are recorded to a precision of one metre and have ground accuracies around 20 metres. MAIN RESULTS: Significant birth excesses were found within short distances of bus stations, railway stations, ferries, railways, and A,B class roads, with a relative risk of 2.1 within 100 m, tapering to neutral after 3.0 km. About 24% of child cancers were attributable to these joint birth proximities. Roads exerted the major effect. CONCLUSIONS: Child cancer initiations are strongly determined by prenatal or early postnatal exposures to engine exhaust gases, probably through maternal inhalation and accumulation of carcinogens over many months. The main active substance is probably 1,3-butadiene.