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41.
摘要 目的:回顾性研究成人胫骨平台骨折的流行病学特征及其变化趋势。方法:以我院2014年1月至2019年12月期间收治的1193例成人胫骨平台骨折患者为调查研究对象,根据患者收治的时间将患者分为A组(2014年1月~2015年12月收治,n=369)、B组(2016年1月~2017年12月收治,n=394)、C组(2018年1月~2019年12月收治,n=430)。对三组患者进行统一的问卷调查,并对三组患者的年龄、职业、致伤原因、骨折分型进行归纳统计,分析探讨成人胫骨平台骨折的流行病学特征及其变化趋势。结果:2014年~2019年成人胫骨平台骨折总体流行病学特征:男性患者数量多于女性患者,年龄主要在40~59岁,以从事体力劳动患者居多,骨折致伤原因中主要以交通事故和室内活动跌倒损伤为主,骨折Schatzker分型中以II型、IV型为主。三组年龄对比有差异性,年龄有逐年升高的趋势(P<0.05)。三组性别比例有显著性差异,男女性别比例差异在逐年缩小(P<0.05)。三组患者在职业类型方面也有显著性差异(P<0.05),但均以体力劳动者居多。在致伤原因中,A组患者以交通事故致伤为主,C组患者以室内活动跌倒损伤为主,组间对比有显著差异(P<0.05)。在骨折分型中,A组以IV型为主,C组以II型为主(P<0.05)。结论:2014年至2019年成人胫骨平台骨折中男性较多,年龄以40~59岁为主,体力劳动者为高发职业,交通事故和室内活动跌倒损伤是最常见的致伤原因,好发骨折分型为Schatzker II型、IV型。变化趋势表现为骨折发病人数逐年上升,发病年龄有老龄化趋势,致伤原因和骨折分型也在逐渐变化。  相似文献   
42.
温度变化和钾添加对扁秆藨草生长及繁殖的影响 人类活动导致的气候变暖和农业面源污染已被认为是影响湿地植物生长和繁殖的重要因素。为了预 测和缓解这些人类活动的影响,研究沼泽植物如何响应这些环境变化具有重要意义。本研究选取在欧亚 大陆广泛分布的莎草科球茎植物扁秆藨草(Bolboschoenus planiculmis)为研究对象,考察气温变化(恒温: 15、20、25 °C及交替温度:20/10和30/15 °C)和钾添加(0、1、3、9 和18 mmol/L)对其生长和繁殖性状 的影响。研究结果表明,高的恒温(20、25 °C)比高的交替温度(30/15 °C)更有利于扁秆藨草球茎的形成, 而地上生物量和株高一般在较高温度下(30/15、25 °C)达到最大值。扁秆藨草的繁殖和生长性状均与施钾量 呈驼峰型关系,最适施钾量在1–3 mmol/L K。高恒温效应和最适钾浓度的交互作用对繁殖性状的促进作 用最大,但是,较高的温度(30/15和25 °C)和0–9 mmol/L的钾浓度只促进了生长性状的生长。综上所述, 扁秆藨草的种群优势度可能受益于全球变暖和额外的钾添加。  相似文献   
43.
种子库和植被物种之间的差异有助于保持新热带稀树草原的功能多样性 本研究的目的是量化种子库和建立的植被对物种组成、功能组成和多样性的贡献,并讨论这些差异对冲积平原植物群落更新和稳定性的影响。我们在巴西潘塔纳尔湿地的一个周期性洪水泛滥的稀树大草原上,在旱季和雨季对分布在5个地点的25个地块(10 m × 1 m)的1.5 m高度的地面覆盖植被和种子库进行了采样。采用出苗法对土壤种子库进行了评价。研究结果表明,种子库物种具有赋予群落更新的特征,而植被则具有稳定性特征。种子库的功能丰富度高于植被,而功能均匀度则低于植被。由于种子库和植被的植物特征不同,使得具有不同功能稳定性和更新特性的物种得以共存,这将有助于维持植物的功能多样性。这可能会让植物种群在应对干旱、火灾和洪水等不同的环境选择时更具有弹性。  相似文献   
44.
高寒湿地是青藏高原地区最重要的生态水源涵养区之一, 也是局部气候的有效调节者, 其动态变化与成因亟待深入研究。该研究基于遥感图像分析、地理信息系统空间分析和景观生态指数分析结合的方法, 以黄河首曲玛曲县高寒湿地为研究对象, 对1995-2018年6期湿地的动态变化进行研究。结果表明, 研究区湿地在1995-2010年间不断退化, 1995-2010年湿地面积总共减少了18 680.31 hm2。在2010-2018年间黄河首曲高寒湿地面积有所增加, 但与20世纪90年代相比, 21世纪初开始湿地的面积普遍呈现下降趋势; 1995-2010年湿地斑块数不断增加, 斑块密度不断增大, 平均斑块面积下降, 景观的破碎度升高; 2010-2015年湿地斑块数和斑块密度减少, 2015-2018年湿地斑块数和斑块密度增加, 平均斑块面积先增大后减小, 景观的破碎度先降低后升高。1995-2010年研究区高寒湿地景观Shannon多样性指数和Shannon均匀度指数均呈现下降的趋势, 湿地的景观结构趋于简单, 景观类型分布更加集中。2010-2018年湿地景观Shannon多样性指数和Shannon均匀度指数均呈现上升趋势, 湿地的景观结构趋于复杂, 景观类型增加且分布更加分散。进一步的驱动力分析表明, 引起黄河首曲高寒湿地景观格局演变的主要因素是蒸发量和降水量, 其次是人口数量和大牲畜数量等人类活动影响。气候因子是影响黄河首曲高寒湿地面积变化的主要原因, 过度的人类经济活动在一定程度上加剧了湿地的变化。  相似文献   
45.
目的:研究对比隐匿性胫骨平台骨折(TPOF)磁共振成像(MRI)、电子计算机断层扫描(CT)检查的影像学表现及其诊断价值。方法:回顾性分析我院自2016年1月至2019年12月拟诊断为TPOF且X线检查表现为阴性的89例患者的临床资料,分别对所有受试者进行MRI、CT检查,且以手术检查为金标准,比较上述两种影像学检查手段诊断TPOF的效能。此外,比较MRI、CT检查诊断TPOF的表观扩散系数以及节段各向异性值以及对TPOF类型的检出率。结果:MRI检查诊断TPOF的灵敏度、特异度及准确度分别为98.61%、94.12%、97.75%,均高于CT检查的79.17%、64.71%、76.40%(均P<0.05)。MRI检查诊断TPOF的表观扩散系数高于CT检查,而节段各向异性值低于CT检查(均P<0.05)。MRI检查对骨皮质骨折的检出率低于CT检查,而对骨小梁骨折的检出率高于CT检查(均P<0.05)。结论:MRI检查诊断TPOF的价值高于CT检查,且在骨小梁骨折的检出率方面优于CT检查,但CT检查应用于骨皮质骨折的诊断价值更高。临床工作中可能通过联合MRI以及CT检查,继而达到提高TPOF检出率的目的。  相似文献   
46.
Modena, founded by the Romans (183 BC), has always been conditioned by water in all its urban history. In the city, numerous archaeobotanical investigations have been carried out in order to reconstruct the natural landscape and human–environment interactions over time. During these investigations, four archaeological sites (two Roman and two medieval) have revealed deposits with a marked character of palaeobiocoenosis, largely resulting from the natural environment surrounding the sites, due to natural “seed rain”. These deposits are characterized by widespread evidence of plants related to water, constituting a valuable archive to investigate habitats which currently have become very rare and threatened, if they have not completely disappeared. The present paper aims to reveal the peculiarities of the Roman/medieval archaeocarpological floristic lists (through a comparison with the flora over the last two centuries in the area of Modena) and highlight the possible causes explaining the presence or the demise of several taxa, considering also the palaeoecological reconstruction of the environment in which they have been found.  相似文献   
47.
This study aimed to establish if the Lower Río de la Plata Basin (LRPB) wetlands can be considered a biogeographic unit. The species of this area were compiled and segregated according to the habitat, selecting only 87 endemic taxa restricted to the LRPB and linked to wetlands. Distributional data of species obtained from the literature, web databases, biological collections, and field trips were georeferenced. The areas of endemism were established as those areas where the distribution of two or more taxa overlaps in groups of rivers’ sections with geographic continuity and were tested with a cluster analysis. This congruence is due to ecological, geomorphological, and historical factors. Four areas of endemism were found: a broad area that comprises the whole study area (Riverine district), which is divided into three nested smaller areas (Paraguay–Paraná Flooding Valleys, Uruguay Basin, and Paraná Delta subdistricts). Then, we analysed 170 taxa distributions to evaluate the relationship between the study area and the neighbouring biogeographic units. According to the results, the study area belongs to the Paraná biogeographic province. Some areas of endemism are hidden inside broader areas and are hardly detected with the currently used biogeographic grid-methods. We propose to combine the information about ecological requirements of each taxon with its georeferenced records to estimate their areas of distribution as a primary step for searching areas of endemism in intracontinental studies.  相似文献   
48.
We investigated the morphology, morphogenesis and small subunit rRNA gene-based phylogeny of three marine urostylids, Uncinata gigantea Bullington, 1940 Bullington, W. E. (1940). Some ciliates from Tortugas. Papers from the Tortugas Laboratory, 32, 179221. [Google Scholar], Holosticha heterofoissneri Hu & Song, 2001 Hu, X., & Song, W. (2001). Morphology and morphogenesis of Holosticha heterofoissneri n. sp. from the Yellow Sea, China (Ciliophora, Hypotrichida). Hydrobiologia, 448, 171179. doi:10.1023/A:1017553406031.[Crossref], [Web of Science ®] [Google Scholar], and Holosticha cf. heterofoissneri. The dorsal morphogenesis of Uncinata gigantea shows de novo formation of two groups of anlagen near the marginal rows. Holosticha cf. heterofoissneri demonstrates fragmentation of the first dorsal kinety anlage as in Holosticha heterofoissneri. Our population of H. heterofoissneri corresponds well with previously described populations in terms of its general morphology and ciliary pattern. Uncinata gigantea can be recognized by its large and highly contractile body, yellowish to brownish cell colour, two types of cortical granules, and 20–30 transversely oriented and densely arranged cirri in the left marginal row, which often overlie the buccal vertex. Based on the new data, especially infraciliature, the genus Uncinata is here redefined. Both the morphology and phylogenetic analyses suggest that the genus Uncinata should be classified within the family Urostylidae. In addition, both morphological and morphogenetic data suggest that Holosticha bradburyae Gong et al., 2001 Gong, J., Song, W., Hu, X., Ma, H., & Zhu, M. (2001). Morphology and infraciliature of Holosticha bradburyae n. sp. (Ciliophora, Hypotrichida) from the Yellow Sea, China. Hydrobiologia, 464, 6369. doi:10.1023/A:1013901621439.[Crossref], [Web of Science ®] [Google Scholar] should be transferred to Uncinata as U. bradburyae (Gong et al., 2001 Gong, J., Song, W., Hu, X., Ma, H., & Zhu, M. (2001). Morphology and infraciliature of Holosticha bradburyae n. sp. (Ciliophora, Hypotrichida) from the Yellow Sea, China. Hydrobiologia, 464, 6369. doi:10.1023/A:1013901621439.[Crossref], [Web of Science ®] [Google Scholar]) comb. nov., due to its possession of a characteristically prominent beak-like, leftwards curved projection and the developmental mode of the dorsal kineties. This assignment is supported by the phylogenetic analyses, which placed Uncinata gigantea in a clade with U. bradburyae (Gong et al., 2001 Gong, J., Song, W., Hu, X., Ma, H., & Zhu, M. (2001). Morphology and infraciliature of Holosticha bradburyae n. sp. (Ciliophora, Hypotrichida) from the Yellow Sea, China. Hydrobiologia, 464, 6369. doi:10.1023/A:1013901621439.[Crossref], [Web of Science ®] [Google Scholar]) comb. nov., and revealed only 1.13% (19 bp) difference in their SSU-rDNA gene sequence.  相似文献   
49.
Six wetland plants were investigated for their effect on the degradation characteristics of chlorpyrifos in nonsterile hydroponic system at constant temperature of 28°C. The results showed that the removal rates of chlorpyrifos in the water of plant systems were 1.26–5.56% higher than that in the control without plants. Scirpus validus and Typha angustifolia were better than other hygrophytes in elimination of chlorpyrifos. The removal rates of the two systems were up to 88%. Plants of acaulescent group had an advantage over caulescent group in removing chlorpyrifos. Phytoaccumulation of chlorpyrifos was observed, and the order of chlorpyrifos concentration in different plant tissues was root > stem > leaf. It was also found that chlorpyrifos and its metabolite TCP decreased rapidly at the initial step of the experiment.  相似文献   
50.
The first overview on the Auchenorrhyncha fauna of peat bogs of the Austrian Bohemian Forest is presented. Seven oligotrophic peat bog sites were studied in 2011 by suction sampler (“G-Vac”) and 93 Auchenorrhyncha species (with 7465 adult specimens) were recorded. Eleven species (about 18 % of the individuals) are tyrphobiontic or tyrphophilous. The relative species abundance plot is not very steep; the six most abundant species represent 50 % of the individuals. The most common species is Conomelus anceps (17 % of the individuals). Compared to the whole Austrian Auchenorrhyncha fauna, the fauna of peat bogs comprises distinctly more univoltine species and more species hibernating in nymphal stage. Densities of adult Auchenorrhyncha in peat bogs are low in spring (about 10–60 individuals per m²) and high in July, with up to 180 (±50) individuals per m². Disturbed peat bogs have higher species numbers and higher Auchenorrhyncha densities in total, but lower numbers and densities in peat bog specialists.  相似文献   
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