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41.
摘要 目的:探讨神经精神性狼疮(NPSLE)患者血清可溶性fractalkine(sFKN)、乳酸脱氢酶(LDH)水平与疾病活动程度的关系,分析NPSLE发病的危险因素。方法:选取2016年1月-2020年12月我院收治的106例系统性红斑狼疮患者,其中44例患者出现神经精神症状(NPSLE组),62例患者未出现神经精神症状(非NPSLE组)。检测血清sFKN、LDH水平,采用SLE疾病活动程度(SLEDAI)评分评估疾病活动程度,根据 SLEDAI评分将NPSLE组患者分为轻度组(17例)、中度组(15例)、重度组(12例)。Spearman秩相关分析血清sFKN、LDH水平与SLEDAI评分之间相关性,多因素Logistic回归分析NPSLE发病的影响因素。结果:NPSLE组血清sFKN、LDH水平、SLEDAI评分均高于非NPSLE组(P<0.05)。重度组血清sFKN、LDH水平高于中度组和轻度组(P<0.05),中度组血清sFKN、LDH水平高于轻度组(P<0.05)。血清sFKN、LDH水平与SLEDAI评分均呈正相关(rs=0.868、0.732,P<0.05)。多因素Logistic回归分析结果显示发病年龄较小、病程较短、未接受正规糖皮质激素治疗、高sFKN、高LDH是NPSLE发病的危险因素(P<0.05)。结论:NPSLE患者血清sFKN、LDH水平均增高,高水平sFKN、LDH与NPSLE发生和疾病活动程度增加有关,临床监测血清sFKN、LDH水平有助于早期识别NPSLE。 相似文献
42.
土壤质量是维持陆地生态系统稳定性与功能多样性的基础。放牧作为草地资源最广泛的利用方式之一,其对草地土壤质量的影响却缺乏量化标准,且两者之间的作用机理尚不明确。以祁连山高寒草原两个季节性牧场为研究对象,结合生态系统耦合与生态系统多功能性,探究了放牧对高寒草原土壤质量的影响与潜在机制。试验结果表明:基于最小数据集,不同放牧率下土壤质量指数差异显著(P<0.05),冬季牧场和春秋季牧场放牧率分别在2.45头月-1 hm-2和0.80头月-1 hm-2时土壤质量指数最高。土壤速效磷、有机碳、氮磷比和土壤pH是决定冬季牧场土壤质量的关键因子,而春秋季牧场中则是土壤有机碳、碳氮比和土壤pH;两个季节性牧场土壤质量指数与物种丰富度指数(P<0.05)和香浓维纳多样性指数(P<0.0001)呈显著正相关。高寒草原季节性牧场放牧地植物群落物种多样性与土壤因子耦合度在0.67—0.81之间,平均耦合度为0.74,属于中度协调;随着放牧率的增加,生态系统多功能性指数逐渐减低且与土壤质量指数变化趋势相似,... 相似文献
43.
Based on our previous research, four sulfated polysaccharide (sPSs) from Tremella and Condonpsis pilosula, sTPStp, sTPS70c, sCPPStp and sCPPS50c, were prepared and their effects on splenic lymphocytes proliferation in vitro and the immune response of ND vaccine in chicken were compared taking the unmodified polysaccharide (uPS) TPStp as control. The results showed that four sPSs could significantly or numerically stimulate splenic lymphocyte proliferation singly or synergistically with LPS in vitro, sTPS70c and sCPPStp demonstrated better effect; promote peripheral lymphocytes proliferation and enhance serum HI antibody titer in chickens vaccinated with ND vaccine, the actions of sPSs were stronger than that of uPS, and sTPS70c at medium dosage presented the best efficacy. These indicated that sulfation modification could improve the immune-enhancing activity of TPS and CPPS, sTPS70c possessed the strongest activity and would be expected as a component of new-type immunopotentiator. 相似文献
44.
Diana Posledovich Tenna Toftegaard Jose A. Navarro‐Cano Christer Wiklund Johan Ehrlén Karl Gotthard 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(4):981-991
Latitudinal clines in thermal reaction norms of development are a common phenomenon in temperate insects. Populations from higher latitudes often develop faster throughout the range of relevant temperatures (i.e countergradient variation) because they must be able to complete their life cycle within a shorter seasonal time window compared to populations at lower latitudes. In the present study, we experimentally demonstrate that two species of butterflies Anthocharis cardamines (L.) and Pieris napi (L.) instead show a cogradient variation in thermal reaction norms of post‐winter pupal development so that lower latitude populations develop faster than higher latitude populations. The two species share host plants but differ in the degree of phenological specialization, as well as in the patterns of voltinism. We suggest that the pattern in A. cardamines, a univoltine phenological specialist feeding exclusively on flowers and seedpods, is the result of selection for matching to the phenological pattern of its local host plants. The other species, P. napi, is a phenological generalist feeding on the leaves of the hosts and it shows a latitudinal cline in voltinism. Because the latitudinal pattern in P. napi was an effect of slow development in a fraction of the pupae from the most northern population, we hypothesize that this population may include both bivoltine and univoltine genotypes. Consequently, although the two species both showed cogradient patterns in thermal reaction norms, it appears likely that this was for different reasons. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 981–991. 相似文献
45.
46.
Optimization of sulfated modification conditions of tremella polysaccharide and effects of modifiers on cellular infectivity of NDV 总被引:2,自引:0,他引:2
Zhao X Hu Y Wang D Guo L Yang S Fan Y Zhao B Wang Y Abula S 《International journal of biological macromolecules》2011,49(1):44-49
Based on our previous research, sulfated modification conditions of Tremella polysaccharide (TPS), the chlorosulfonic acid to pyridine (CSA-Pry) ratio, reaction temperature and time, were optimized by L9 (34) orthogonal design taking the yield and degree of sulfation (DS) of modifiers as indexes. Two TPSs, TPStp and TPS70c, were modified under optimized conditions. The effects of two modifiers, sTPStp and sTPS70c, on cellular infectivity of NDV were determined by MTT method taking the non-modified TPStp, TPStc and TPS70c as controls. The results showed that the optimized modification conditions were reaction temperature of 80 °C, CSA-Pry ratio of 1:6 and reaction time of 1.5 h. Five polysaccharides at proper concentrations could significantly inhibit the infectivity of NDV to CEF. The virus inhibitory rates of sTPStp at 1.563 μg mL−1 group were the highest and significantly higher than those of other three non-modified polysaccharide groups in three sample-adding modes. This indicated that sulfated modification could significantly improve the antiviral activity of TPS. sTPStp possessed the best efficacy and would be as a component of antiviral polysaccharide drug. 相似文献
47.
目的:分析骨创伤患者的血浆D-二聚体、纤维蛋白原水平及其与创伤程度的相关性。方法:收集2015年1月至2016年1月我院收治的骨创伤患者180例作为观察组,选择同期接受体检的健康者100例作为对照组。动态监测两组受检者入院后第1、3、6、10 d的血浆D-二聚(DD)和纤维蛋白原(FIB)的水平,并分析DD和FIB水平与骨创伤程度的相关性。结果:入院后第1、3、6、10 d,观察组的FIB和DD水平均出现下降趋势,但均显著高于对照组,差异具有统计学意义(P0.05)。重度创伤组和中度创伤组患者的FIB水平显著高于轻度创伤组,且重度创伤组FIB水平显著高于中度创伤组,组间比较差异均具有统计学差异(P0.05)。从入院第1 d至10 d,3组患者的FIB水平均出现显著降低(P0.05)。轻度创伤组患者的DD水平最低,其次是中度创伤组,重度创伤组最高,组间比较差异均具有统计学差异(P0.05)。从入院第1 d至10 d,3组患者的DD水平均出现显著降低(P0.05)。此骨创伤患者创伤严重程度与FIB和DD的水平均呈现出显著正相关关系(r=0.64,P=0.003;r=0.71,P=0.002)。结论:骨创伤患者的血浆FIB和DD水平显著高于健康人,与创伤程度呈显著正相关,可能作为骨创伤患者病情程度和预后评估的生物指标。 相似文献
48.
Melinda ChuaKelvin Chan Trevor J. HockingPeter A. Williams Christopher J. PerryTimothy C. Baldwin 《Carbohydrate polymers》2012,87(3):2202-2210
Here we present a comparison of commonly used methodologies for the extraction and quantification of konjac glucomannan (KGM). Compositional analysis showed that the purified konjac flour (PKF) produced using a modified extraction procedure contained 92% glucomannan, with a weight average molecular weight (Mw), polydispersity index (PDI) and degree of acetylation (DA) of 9.5 ± 0.6 × 105 g mol−1, 1.2 and 2.8 wt.%. These data, plus Fourier-transform infrared spectral (FTIR) and zero shear viscosity analyses of the extract (PKF) were all consistent with the literature. Comparison of three existing methodologies for the quantitative analysis of the KGM content of the PKF, namely 3,5-dinitrosalicylic acid (3,5-DNS), phenol-sulphuric acid and enzymatic colorimetric assays; indicated that the 3,5-DNS colorimetric assay was the most reproducible and accurate method, with a linear correlation coefficient of 0.997 for samples ranging from 0.5 to 12.5 mg/ml, and recoveries between 97% and 103% across three spiking levels (250, 500 and 750 μg/g) of starch. These data provide the basis of improved good laboratory practice (GLP) for the commercial extraction and analysis of this multifunctional natural polymer. 相似文献
49.
Stream-dwelling insects and extremely low frequency electromagnetic fields: a ten-year study 总被引:1,自引:0,他引:1
Changes in the structure of benthic insect communities at an experimental site and at a reference site in the Ford River, Michigan were monitored over a 10-year period to determine whether extremely low frequency electromagnetic fields (ELF) affected those communities. Five of 10 biotic parameters monitored are presented: taxon evenness (J), richness (S), numerical dominance of chironomids, and total insect mass. Data were separated into three seasons because coefficient of variation values were lower in the summer than in the spring and fall. Two-way ANOVA tests for the biotic variables were often significantly different between sites and among years, but the interaction terms were less frequently significant. Biotic parameters were regressed against stream discharge, water temperatures, years, and ELF cumulative ground field exposures. At the experimental site, discharge accounted for more variation than did water temperature or years for all biotic parameters except chironomid numerical dominance in the fall. Intervention analyses, using the B.A.C.I parametric or the R.I.A non-parametric showed significant differences in three of 15 cases; namely, for the highly varying chironomid numerical dominance values in the spring and fall and for the low varying total insect mass values in the summer. For those tests, the Before Impact period spanned April 1984 through May 1986. The After Impact period (full ELF power) spanned June 1989 through August 1993. Trend analysis for total insect mass at the experimental site in the summer showed discharge to be more important than water temperatures or ELF ground field exposures. Natural physical factors appear to be more important than the anthropogenic ELF fields in accounting for seasonal and yearly changes in the community. 相似文献
50.
玉米优异地方种质资源的筛选与评价 总被引:18,自引:2,他引:18
本文对20个玉米优异地方品种资源主要农艺性状进行了研究,运用灰色系统理论的方法,分析了资源的综合性状及各性状间的关系。研究结果表明,株高影响穗粗,穗位高影响穗长,株高和穗位均低的资源不会有较高的单株粒重;叶片数对资源的筛选、利用有一定的影响,对穗长、穗粗、单株粒重有显著影响;利用生育期较短的资源可能会选出单株粒重较高的自交系和杂交种。据此结果结合育种目标评价,筛选出白头霜、高油玉米、洛阳85、白鹤、二夏、品综2号、本地黄玉米、金皇后8个玉米地方品种,综合农艺性状好,具有较高的利用价值。 相似文献