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关键词： General species concept   Population aggregation analysis   Tree based species delimitation   Mantel test   Museum collections   Polymorphic characters   LONG-TERM STARVATION   CRYPTIC DIVERSITY   EVOLUTIONARY PROCESSES   PHYLOGENETIC ANALYSIS   NICHE CONSERVATISM   GAMMARUS-FOSSARUM   BIODIVERSITY   DELIMITATION   SYSTEMATICS   RESPONSES  

摘要： Natural history museum collections harbour valuable information on species. The usefulness of such data critically depends on the accurate identification of species, which has been challenged by introduction of molecular techniques into taxonomy. However, most collections may suffer from DNA degradation, due to age and/or improper preservation; hence the identification of specimens depends solely on morphological features. This study explores how and to what extent morphological data can help to solve ambiguous taxonomic cases based on selected species concepts and with the use of operational criteria in a species-hypothesis testing procedure. The studied taxon, the Niphargus tatrensis species complex, comprises freshwater subterranean amphipods, distributed across Central Europe, the taxonomic status of which was debated extensively between 1930 and 1960. Using the general species concept, character- and tree-based operational criteria reveal northern and southern diagnosable and exclusive lineages identified here as N. tatrensis Wrzesniowski, 1888 and N. scopicauda sp. n., respectively. The remaining populations represent the non-exclusive N. aggtelekiensis Dudich, 1932, which occurs from the eastern Alps to Hungary. In the entire complex, altitudinal distribution is largely limited to areas above 400 m, where the mean annual temperature never exceeds 9 degrees C. Seemingly well-defined distributional ranges of N. tatrensis and N. aggtelekiensis are fragmented in an ecological sense, which raises the question whether two of the three species recognised here actually consist of several unidentified taxa. Morphological similarity between the species, numerous polymorphic features, and the association with cool temperatures lead to a hypothesis in which fragmentation of the ancestral range occurred during post-Pleistocene climate warming, reducing gene flow across lowland populations due to niche conservatism of the ancestral species and/or to invasion of competitive

关键词： Electromyography   Evoked contractions   Maximal voluntary contractions   Medial gastrocnemius   Soleus   MUSCLE STRENGTH   PEAK TORQUE   WARM-UP   POWER   ELECTROMYOGRAPHY   PERFORMANCE   FLEXIBILITY   FORCE   ANGLE  

摘要： The present study aimed to investigate the immediate effects of 15 min static or sub-maximal contract-relax stretching modalities on the neuromuscular properties of plantar flexor muscles. Ten male volunteers were tested before and immediately after 15 min static or contract-relax stretching programs of plantar flexor muscles (20 stretches). Static stretching consisted in 30 s stretches to the point of discomfort. For the contract-relax stretching modality, subjects performed 6 s sub-maximal isometric plantar flexion before 24 s static stretches. Measurements included maximal voluntary isometric torque (MVT) and the corresponding electromyogsraphic activity of soleus (SOL) and medial gastrocnemius (MG) muscles (RMS values), as well as maximal peak torque (Pt) elicited at rest by single supramaximal electrical stimulation of the tibial nerve. After 15 min stretching, significant MVT and SQL RMS decreases were obtained (-6.9 +/- 11.6% and 6.5 +/- 15.4%, respectively). No difference was obtained between stretching modalities. Pt remained unchanged after stretching. MG RMS changes were significantly different between stretching modalities (-9.4 +/- 18.3% and +3.5 +/- 11.6% after static and contract-relax stretching modalities, respectively). These findings indicated that performing 15 min static or contract-relax stretching had detrimental effects on the torque production capacity of plantar flexor muscles and should be precluded before competition. Mechanisms explaining this alteration seemed to be stretch modality dependent. (C) 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

关键词： Hydrophilic interaction chromatography   Reversed-phase chromatography   Column classification   Chromatographic fingerprint   Chemometrics   Natural product analysis   CHINESE HERBAL MEDICINES   LIQUID-CHROMATOGRAPHY   QUALITY-CONTROL   SEPARATION   RETENTION   LUCIDUM   LINGZHI   SYSTEM   HPLC  

摘要： Acetonitrile-water extracts of several Ganoderma species - a mushroom being used in Traditional Chinese Medicine-were analysed by liquid chromatography-UV detection in hydrophilic interaction chromatography (HILIC) and reversed-phase (RP) elution modes A set of six polar stationary phases was used for HILIC runs These columns had remarkably different separation properties under binary gradient conditions as evinced by hierarchical cluster analysis on retention patterns of seven test Compounds Complementary measurements of RP chromatograms were carried out on a C-18 packing Injection precision (it = 5) and intra-clay precision (it = 5) were each <2 0% RSD (HILIC) and <0 7% RSD (RP) for relative retention times of main characteristic peaks of a sample exit act while for relative peak areas RSD values were max. 6.8%. Repetitive analysis (it = 7) of a processed sample stored in the autosampler tray for 48 h was used to confirm within-sequence sample stability Eleven Ganoderma luctdum samples served as it training set for the construction of column-specific simulated mean chromatograms Validation with twelve samples comprising G. lucidum. Ganoderma sinense. Ganoderma atrum, and Ganoderma tsugac by cot relation coefficient based similarity evaluation of peak patterns showed that a discrimination of G. lucidum from other Ganoderma species by means of chromatographic fingerprints is conceptually possible on all columns. except of a bare silica packing The importance of the combined use of RP and HILIC fingerprints to Improve the rate of correct sample classification was demonstrated by the fact that each one G sinense specimen was wrongly assigned being G lucidum by all HILIC fingerprints but not the RP fingerprint and vice versa The present data revealed that (I) the analysis of complex biological materials by quasi orthogonal chromatographic modes such as HILIC and RP may deliver more discriminative information than single-mode approaches which strengthens the reliability

关键词： 肝硬化   血小板功能   血小板粘附试验   血小板聚集试验  

摘要： 本文通过对63例肝硬化患者进行的PAdT、PAgT两项血小板功能试验，就肝硬化患者肝功损害同血小板功能异常的关系作一初步的撂讨。

关键词： 医院感染控制   感染管理工作   检验科   预防   消毒隔离管理   生物安全防护   医院感染管理   医源性感染  

摘要： 检验科是医院感染控制中的重要环节，也是医院感染发生的高危区域，如果没有健全的医院预防感染制度及措施，检验人员防护意识淡薄，不加强实验室的生物安全防护和消毒隔离管理，将会发生生物危害及引起医源性感染，造成巨大的经济损失。因此加强检验科医院感染管理是预防医院感染的关键。

关键词： 造作伤   损伤   凶杀案   法医学鉴定  

摘要： 1案件资料 造作伤的鉴定并不常见，常常是侦破案件和确定案件性质的关键，在许多重大疑难案件的侦破中占有重要地位。虽然造作伤有其具体的特点及特征，但所有自己能形成的损伤他人加害或他人合作均可以形动作应手掌着地，

关键词： 智能包装   应用   分类   智能材料   包装材料   信息收集   包装系统   化管理  

摘要： 一、什么是智能包装 随着智能材料不断发展，它的应用范围拓展到了包装，于是出现了“智能包装”的概念。所谓智能包装，是指利用新型的包装材料、结构与形式对商品的质量和流通安全性进行积极干预与保障；利用信息收集、管理、控制与处理技术完成对运输包装系统的优化管理等。

关键词： 劳动合同   合同形式   录取通知书   工作职责   工作时间   社会保险   补偿  

摘要： 【案例】何某在某服装公司工作，单位提供何某录取通知书．其上明确劳动期限、薪金、工作职责、工作时间、社会保险待遇等事项。后公司解聘何某，何某要求给予相应补偿，公司认为双方没有签订正式劳动合同．不能按合同给予补偿。

关键词： 卫生检验   疾病预防控制   作用  

摘要： 卫生检验工作是疾病预防控制中心基本职能的一部分.多年来,卫生防疫的各项工作,不论是疾病预防控制工作还是卫生监督管理工作的开展都要以卫生检验所提供的科学数据为行动指导,卫生检验不仅为疾病预防及卫生监督提供最基础的数据资料,而且卫生检验技术的发展和提高更进一步促进了各项工作走向规范化与标准化.

关键词： 网络联接   校企合作   资源共享  

摘要： 基于网络理论构建了网络联接、资源共享、合作绩效概念模型,通过对252名样本的分析证实了校企之间网络联接通过促进双方之间的资源共享程度实现网络绩效关系的客观存在。