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161.
Michiel?M?Zandbelt Judith?Vogelzangs Leo?BA?van de Putte Walther?J?van Venrooij Frank?HJ?van den HoogenEmail author 《Arthritis research & therapy》2003,6(1):R33
The presence of anti-α-fodrin autoantibodies has been reported to be a highly specific and sensitive test for the diagnosis of Sjögren's syndrome (SjS). We looked (in Nijmegen) for anti-α-fodrin, anti-Ro60, and anti-La autoantibodies in a cohort of 51 patients with rheumatic diseases (primary SjS [21], secondary SjS [6], rheumatoid arthritis [RA] [12], systemic lupus erythematosus [SLE] [6], and scleroderma [6]) and in 28 healthy subjects, using ELISA, immunoblotting, and immunoprecipitation. The same samples were analyzed with an alternative anti-α-fodrin ELISA in Hanover. The Nijmegen ELISA of the sera from primary SjS showed sensitivities of 43% and 48% for IgA- and IgG-type anti-α-fodrin antibodies, respectively. The Hanover ELISA showed sensitivities of 38% and 10% for IgA- and IgG-type anti-α-fodrin antibodies, respectively. The ELISAs for α-fodrin showed six (Nijmegen) and four (Hanover) anti-α-fodrin-positive RA sera. IgA and IgG anti-fodrin antibodies were also present in four patients with secondary SjS. The sensitivities of Ro60 and La-antibodies in the Nijmegen ELISA were 67% and 62%, respectively. Unlike anti-α-fodrin antibodies, all anti-Ro60 and anti-La positive sera could be confirmed by immunoblotting or RNA immunoprecipitation. Thus, anti-Ro and anti-La autoantibodies were more sensitive than anti-α-fodrin autoantibodies in ELISA and were more frequently confirmed by other techniques. Anti-La antibodies appear to be more disease-specific than anti-α-fodrin antibodies, which are also found in RA sera. Therefore, the measurement of anti-α-fodrin autoantibodies does not add much to the diagnosis of Sjögren's syndrome. 相似文献
162.
目的:在教育理论的指导下,通过问卷调查的形式对一年级学生的生活、学习、心理健康状况等方面的适应性问题进行调研。方法:采用随机抽样的原则,以抽到的班级所有符合条件的大学新生作为调查对象。采用自制的一般人口学特征问卷、高考志愿填报情况调查表、教学软硬件建设满意度调查表、目前学习状况及未来就业去向调查表、症状自评量表对46名大学新生进行调查。结果:调查班级学生中,多数学生来自农村家庭;与"70版、80后"相比,"90后"学生在职业选择方面具有更多的自主选择权;对学校在软硬条件方面亦提出更高的要求;受限于近期个人目标,缺乏长远人生目标,可持续发展能力差。心理问题阳性检出率为24%,排名在前4位的心理健康问题依次是:强迫、抑郁、焦虑、躯体化,男女生表现个有不同。结论:传统教育思维仍试图在极短时间里完成适应性教育工作,致使抽象理论与学生现实需求相脱节。陌生的环境、迥然不同的学习方式、全方位转变的人际关系使得新生心理问题出现叠加性、多重性的特点。相关部门应改变适应教育模式,建立新生适应教育活动的长期反馈机制和评估体系,才能更好的服务于新生教育工作。 相似文献
163.
对中国宽漠甲属Sternoplax Frivaldszky进行了分类整理,共计4亚属10种,含2新种:双脊宽漠甲Sternoplax bicarinata sp.nov.和隆脊宽漠甲Sternoplax lineola sp.nov.;给出中国已知种检索表及其名录,绘制了新种的形态特征图.模式标本保存于河北大学博物馆. 相似文献
164.
Cleland Elsa E. Lind Eric M. DeCrappeo Nicole M. DeLorenze Elizabeth Wilkins Rachel Abbott Adler Peter B. Bakker Jonathan D. Brown Cynthia S. Davies Kendi F. Esch Ellen Firn Jennifer Gressard Scott Gruner Daniel S. Hagenah Nicole Harpole W. Stanley Hautier Yann Hobbie Sarah E. Hofmockel Kirsten S. Kirkman Kevin Knops Johannes Kopp Christopher W. La Pierre Kimberly J. MacDougall Andrew McCulley Rebecca L. Melbourne Brett A. Moore Joslin L. Prober Suzanne M. Riggs Charlotte Risch Anita C. Schuetz Martin Stevens Carly Wragg Peter D. Wright Justin Borer Elizabeth T. Seabloom Eric W. 《Ecosystems》2019,22(7):1466-1477
Ecosystems - Anthropogenic activities are increasing nutrient inputs to ecosystems worldwide, with consequences for global carbon and nutrient cycles. Recent meta-analyses show that aboveground... 相似文献
165.
Brad J. Farmilo Brett A. Melbourne James S. Camac John W. Morgan 《Austral ecology》2014,39(4):416-423
The establishment of commercial tree plantations is a common cause of habitat fragmentation globally, yet the influence of this land use on plant species density in fragmented native forests requires further understanding. Theory predicts species density will be highest in large areas of habitat, and should decline as area is reduced, but whether these effects are scale‐dependent is largely unknown. We assessed plant species density (total, common and uncommon species) in experimentally fragmented eucalypt forest remnants (0.25, 0.88, 3.06 ha) surrounded by a pine plantation, at three spatial scales using nested quadrats. Specifically, we consider how plant species density varies across three different sized fragments, and whether the response of species density is magnified in common or uncommon species. Species density in small fragments was higher than continuous forest for all species groupings at the smallest spatial scale (1 m2), and for total and common species at the next smallest spatial scale (16 m2). No species groupings responded to reductions in habitat area at the largest spatial scale (144 m2). We suggest that pine plantations may cause higher species density in small fragments via two mechanisms, either by allowing species to infill unoccupied areas within small fragments, or by buffering small fragments from species losses during a severe and prolonged drought. In both cases we suspect reduced moisture stress (e.g. increased soil moisture, higher shading and reduced temperature) in small fragments has led to the observed changes in species density. 相似文献
166.
中国洞穴蜘蛛多样性及其对洞穴环境的适应 总被引:1,自引:0,他引:1
对中国洞穴蜘蛛的多样性、地理分布信息进行了详细的闸述.初步探讨了洞穴蜘蛛对洞穴环境的适应性特征及其进化机制.我国洞穴蜘蛛目前已知16科27属80种,其巾暗蛛科、弱蛛科、泰莱蛛科和巨蟹蛛科物种最多;在属级阶元上,以弱蛛属Leptoneta14种、泰莱蛛属Telema lO种、龙角蛛属Draamar如和巾遁蛛属Sinopoda各9种,宽隙蛛属Platocoelotes 8种居多.我国洞穴蜘蛛主要集中分布在贵卅、海南、云南、北京、浙江、广西等喀斯特洞穴较为密集地区,在河北、河南、湖北和湖南也有部分报道.在不同地区分布的洞穴蜘蛛类群或优势类群及区系成分等都存在较大差异.洞穴蜘蛛中约有20%~30%的种类凶为长期生活在黑暗无光、食物匮乏以及缺乏温度和光周期的季节调节等特殊环境,出现了一些地表生境蜘蛛类群中所没有的刘洞穴环境的适应性特征,如缺乏体色素、眼退化共至无眼、附肢延长、全身牛有很多具较敏锐触觉和嗅觉功能的感觉毛、繁殖无季节性、耗氧量降低而新陈代谢缓慢、代谢率降低、产牛的后代少、单个卵粒包含更多的营养等. 相似文献
167.
Statistical models of invertebrate distribution on Macquarie Island: a tool to assess climate change and local human impacts 总被引:2,自引:2,他引:0
Sub-Antarctic islands are good model systems in which to study the ecological effects of human impacts, particularly global
climate change and alien species. Invertebrates form a central component of these ecosystems. We conducted a stratified survey
of 69 sites on sub-Antarctic Macquarie Island and used logistic regression models to describe the distribution of 14 abundant
invertebrate species. We also developed a statistical model of windspeed based on topography. The distributions of individual
species were described by different combinations of aspect, altitude and vegetation type. Ordination of sites based on species
composition showed strong effects of altitude and vegetation on invertebrate assemblages. The species distribution models
provide a tool for detecting, monitoring and predicting effects of climate change and alien species on biota and ecosystem
processes.
Accepted: 30 August 1998 相似文献
168.
169.
170.
Two populations of Anadara senilis were sampled periodicallyin a lagoon of Senegal. Spatfall occurs in summer during therainy season. Population density decreases from about 50, 000.m2,two months after spatfall, down to 6, 750 one year later and750 after 28 months. The average growth, measured on the surfaceof the shell, following the umbo rim axis is 0.8 mm per month.The main reduction in growth rate occurs in winter and endsby the deposition of a growth ring. A second growth reductiontakes place during the rainy season and sometimes ends by aweak growth ring. The microgrowth increments are conspicuousand widest during spring equinox. They are not directly relatedto the tidal cycle, but it was impossible to determine if theyhave a tidal or a daily periodicity. (Received 11 February 1990; accepted 16 July 1993) 相似文献