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61.
本项目采用人体测量法,测量了976名(男性528人,女性448人)湖南土家族成人的身高、体质量以及肱三头肌、肩胛下、髂前上和小腿内侧皮褶的厚度,并根据公式计算体密度、体脂率、脂肪质量、脂肪质量指数、瘦体质量和瘦体质量指数。结果显示随年龄增长,小腿内侧皮褶厚度值逐渐减小,肱三头肌、肩胛下和髂前上棘皮褶以及体脂率、脂肪质量、瘦体质量、体质量指数、脂肪质量指数和瘦体质量指数值先增大后减小,体密度值先减小后增大;各年龄组中体密度、瘦体质量及其指数值女性明显低于男性,4项皮褶厚度值以及体脂率、脂肪质量及其指数值女性高于男性;与布朗族等24个族群比较,湖南土家族成人皮褶厚度处于中等水平,与门巴族、珞巴族、僜人、彝族等族群的亲缘关系较近。  相似文献   
62.
目的:研究早期糖尿病视网膜病变患者黄斑区视网膜厚度与相关生化指标糖化血红蛋白(HbA1C)的关系。方法:糖尿病组20例40眼,男12例,女8例;糖尿病病程为5~10年;对照组20例40眼,男14例,女6例,应用光学相干断层扫描(OCT)测量黄斑区视网膜厚度,应用相关生化仪检测糖尿病组的糖化血红蛋白比(HbA1C)。比较两组黄斑区视网膜的厚度,包括黄斑中央厚度(CPT),黄斑中心凹下厚度(SCMT),黄斑容积(TMV),分析糖尿病组黄斑区厚度与相关生化指标的HbA1C关系。结果:糖尿病组所选患者黄斑区厚度比正常组大t=4.0772(P0.01),黄斑区视网膜厚度与糖化血红蛋白(HbA1C)比呈正相关t=3.927(P0.05)。结论:对于糖尿病视网膜病变的患者,检测糖化血红蛋白(HbA1C)变化,有利于预测早期糖尿病视网膜病变并发症的发生。  相似文献   
63.
为探究喀斯特次生林地上生物量与环境因子的关系,该文以黔中普定县喀斯特天龙山典型次生林样地为研究对象,采取单物种及不同径级组地上生物量模型计算优势种及群落生物量,采用空间分布图描述环境因子与群落地上生物量空间分布状况,利用相关性检验(Pearson)、一般线性模型(GLM)以及冗余分析(RDA)讨论群落、生活型、物种地上生物量与环境因子的关系。结果表明:(1)喀斯特次生林群落地上生物量总量为106.94 t·hm-2,优势种地上生物量占整个样地的91.77%,其中常绿植物高于落叶,窄叶柯(Lithocarpus confinis)与化香树(Platycarya strobilacea)地上生物量在群落中占比最高,分别为34.23%和34.37%。(2)岩石裸露率空间分布呈现明显的上下梯度差异,上坡显著大于下坡,坡度与土壤厚度空间分布不连续,无明显规律。(3)群落地上生物量与土壤厚度呈显著正相关,二者空间分布趋于一致,土壤厚度是群落地上生物量的主要影响因子,岩石裸露率与坡度对群落地上生物量的影响较低。(4)对于不同生活型,岩石裸露率对地上生物量的影响程度最高,土壤厚度...  相似文献   
64.
摘要 目的:探讨与研究加减黄芪丹参饮联合优思悦治疗多囊卵巢综合征的效果及对外周血Th17/Treg免疫失衡的影响。方法:选择2018年7月到2022年1月在本院诊治的多囊卵巢综合征患者66例作为研究对象,根据1:1简单分配原则把患者分为中药组与对照组各33例。对照组给予优思悦治疗,中药组在对照组治疗的基础上给予加减黄芪丹参饮治疗,所有患者都治疗观察3个月经周期,测定与计算外周血Th17/Treg免疫失衡情况。结果:治疗后中药组的总有效率为100.0%,与对照组的81.8%相比明显增高(P<0.05)。两组治疗后的Th17/Treg值都明显低于治疗前(P<0.05),中药组与对照组相比也明显降低(P<0.05)。两组治疗后的子宫内膜厚度与最大卵泡直径都明显高于治疗前(P<0.05),治疗后中药组与对照组相比也明显提高(P<0.05)。两组治疗后的血清雌二醇(E2)含量明显高于治疗前(P<0.05),血清催乳素(PRL)含量明显低于治疗前(P<0.05),治疗后中药组与对照组都有明显差异差异(P<0.05)。结论:加减黄芪丹参饮联合优思悦治疗多囊卵巢综合征能有效调节外周血Th17/Treg免疫失衡,促进性激素分泌正常,提高患者的子宫内膜厚度与最大卵泡直径,提高患者的总体治疗效果。  相似文献   
65.
薏苡种子的糊粉层及亚糊粉层细胞的组织化学和超微结构   总被引:1,自引:0,他引:1  
薏苡(Coixlacryma-jobi)种子的糊粉层为1层细胞,径向细胞壁内含有胞间连丝,有细胞核,冰箱内浸泡的材料,未见细胞器,室温浸泡的,则观察到很多核糖体及一些嵴不明显的线粒体。细胞内充 了大量糊粉粒及脂体,糊粉粒含蛋白质,不溶性多糖,可被TBOpH4.4染成绿色,基质内通常有1个球状体,球状体含有脂肪,但不被ABB和PAS及TBOpH4.4染色。脂体大小悬殊,随机分布。亚糊粉层细胞含有许多复合淀粉粒及小形蛋白质体。蛋白质体呈弱的PAS正反应,亦可被TBOpH4.4染成绿色,并具有同心圆坏结构,中央具核心或不具,边缘具裂隙或否。内部胚乳具很多大的简单淀粉粒,蛋白质体同心圆环结构不甚明显。对薏苡与其他禾本科植物的糊粉层细胞,糊粉粒及胚乳蛋白质体的结构进行了比较。  相似文献   
66.
醋酸酐分解作用与花粉形状体积的变化   总被引:1,自引:0,他引:1  
本文利用作者研究的26科56属63种现代花粉的测量统计资料,对醋酸酐的分解作用与花粉形状体积变化的相互关系作了一些初步的探讨,应用小样本的t检验方法,对醋酸酐分解前后花粉粒的大小形状差异进行了分析,发现:形状变化有趋长倾向,即P/E值增加;体积变化符合伍德豪斯效应(Wodchouse effect)。即本身俱本小的花粉粒体积变化小,个体大的花粒粒体积变化大,球形具散孔花粉,超长球形个体很的花粉一般不发生明显的形状和体积的变化,具沟花粉极轴增长明显,扁球形花粉较长球形花粉变化显著,外壁厚的,纹饰粗的花粉变化较大,花粉粒形体变化是醋酸酐分解破坏花粉粒内含物引起外壁张力变化的结果。  相似文献   
67.
《植物生态学报》2016,40(8):775
Aims In the cold life zones, snow cover is a comprehensive environmental factor that directly influences soil temperature, soil water content, light and nutrient availability. Plants in these zones develop a series of unique mechanisms involving phenological characteristics, reproductive strategies, physiology and morphology to adapt to environmental changes. This paper is focused on the responses of plant leaf traits, height and biomass partitioning to variations in snow cover thickness, in order to better understand the responses of plant functional traits and specific adaptation strategies under global climate change scenarios. Methods Three transects were established along a gradient of snow cover in an alpine meadow of Mt. Kaka, in the eastern Qinghai-Xizang Plateau. Primula purdomii, Pedicularis kansuensis and Ranunculus tanguticus, which are three widely distributed and dominant ephemerals, were sampled and studied, particularly at their blooming stages. Plant height, specific leaf area (SLA) and biomass partitioning were measured accordingly. Important findings The values of SLA in Pedicularis kansuensis and R. tanguticus were relatively greater under better soil conditions; it was smaller in Primula purdomii with thick snow cover. The relationship between aboveground biomass and belowground biomass in Primula purdomii was allometric at sites with both thick and thin snow cover. No significant relationships were found between aboveground biomass and belowground biomass in Pedicularis kansuensis and R. tanguticus at some individual sites. However, when samples of the three species were pooled, the relationships between aboveground biomass and belowground biomass were allometric at all sites, which did not support isometric scaling hypothesis. In addition, on sites with either thick or thin snow cover, aboveground biomass had greater rate of accumulation than belowground biomass; whereas on sites with medium snow cover, the rate of biomass accumulation was greater for belowground component than aboveground component. Functional traits and biomass variables were better correlated in Primula purdomii and Pedicularis kansuensis than in R. tanguticus.  相似文献   
68.
目的探索性别对小鼠皮肤屏障功能的影响。方法用丙酮-乙醚法和胶带粘贴法复制皮肤屏障功能障碍模型、观察性别对皮肤屏障障碍模型小鼠的表皮厚度和丝聚合蛋白(FLG)表达的影响。结果与正常对照组相比,丙酮-乙醚组和胶带粘贴组小鼠表皮厚度增宽(P0.05);正常对照组雄鼠与雌鼠相比,表皮厚度无差异;而丙酮-乙醚组和胶带粘贴组雌鼠表皮厚度均较同组雄鼠增加(P0.05)。丙酮-乙醚组和胶带粘贴组与正常对照组相比,FLG蛋白表达水平降低(P0.05),同组雄鼠表达水平均低于雌鼠(P0.05)。结论皮肤机械屏障功能被破坏后,小鼠的表皮厚度变化存在性别差异,而FLG蛋白表达在正常或是皮肤屏障障碍小鼠中的性别差异均有统计学意义,提示在研究小鼠皮肤屏障障碍相关疾病的发病机制和治疗措施时应重视性别差异。  相似文献   
69.
《植物生态学报》2017,41(5):529
Aims The correlations between leaf thickness and vein traits influenced the leaf hydraulic dynamic balance, and there were important meanings to reveal ecophysiological mechanisms of plant leaves water transport and growth rate. Our objective was to study the changes in the relationship between leaf thickness and vein traits (vein diameter, vein density) of Achnatherum splendenspopulations by using standardized major axis estimation (SMA) method under different soil moisture conditions located in flood plain wetland of Zhangye.Methods The study site was located at flood plains wetland of Zhangye, Gansu Province, China. Selecting a starting point along the vertical direction of the river, in turn, along the soil moisture gradient, four plots were set up at intervals of 40 m, plot I (50.07%), plot II (38.77%), plot III (31.5%) and plot IV (20.4%). From each of the four sample plots, seven samples were collected, resulting in (5 m × 5 m) a total of 28 samples. Community traits (height, density) and soil physical and chemical properties were investigated. Six individual samplings of A. splendens from each plot were used to measure the leaf thickness, vein density and vein diameter in laboratory. In addition, the photosynthetically active radiation (PAR), leaf net photosynthetic rate (Pn) and transpiration rate (Tr) of A. splendens were measured in natural environment. The 28 plots were categorized into groups I, II, III and IV, and SMA estimation method was then used to examine the allometric relationship among leaf thickness, vein density and vein diameter. Important findings With a decreased soil moisture, the plant density and height displayed a pattern of steadily declining, while the soil electrical conductivity increased, In addition, the vein density, leaf thickness, water use efficiency (WUE), PAR and twig number of A. splendens displayed a pattern of initial decrease, whereas the vein diameter and Tr increase gradually, Pn and plant high displayed changing trends of increasing-decreasing. The leaf thickness was negatively associated with the vein density, vein diameter, and the relationship varied with the soil moisture conditions (p< 0.05). There was a significant positive relationship (p < 0.05) between the leaf thickness and vein density. The SMA slope of the regression equation gradually decreased and was significantly different from 1.0 (p < 0.05) on plot I and IV. In addition, along decreased soil moisture, the standardized major axis slope of regression equation in the scaling relationships between the leaf thickness and vein diameter gradually increased and was significantly different from -1.0 (p < 0.05) on plot I and IV.  相似文献   
70.
目的:通过研究颈动脉内-中膜厚度(carotid Intimal medial thickness cIMT)及踝肱指数(ankle-brachial index,ABI)与冠心痛患者的相关性,探讨动脉硬化和动脉粥样硬化之间的相关性.方法:本研究入选264例在本院行冠脉造影的患者,按冠脉造影的结果分为对照组和冠心痛组,冠心痛组根据冠脉病变程度进一步分为单支、双支、多支病变组.所有入选者在冠脉造影前用日本ALOKAα 7超声检测cIMT,用日本科林无创动脉硬化测定仪测量两侧ABI.结果:冠心痛组cIMT明显高于对照组,踝臂指数明显低于对照组,差异有统计学意义(P<0.05);冠状动脉病变程度分析中:cIMT随着冠脉病变程度加重均有增高趋势,其中多支病变、双支病变组cIMT和颈动脉斑块积分均高于单支病变组、对照组,单支病变组cIMT和颈动脉斑块积分也明显高于对照组:ABI却随着冠脉病变程度加重均有降低趋势,多支病变组ABI均低于双支、单支痛变组和对照组,双支、单支痛变组ABI也明显低于对照组,差异有统计学意义(P<0.05).结论:cIMT和ABI与冠心痛密切相关,在一定程度上可以预测冠心痛冠脉病变程度.  相似文献   
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