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941.
以提高金针菇单瓶产量为目的,以常规生产为对照,通过单因素试验、Plackett-Burman试验、响应面优化法、验证试验分析培养基装瓶量、灭菌前pH、接种量、搔菌深度、搔菌补水量对金针菇单瓶平均产量的影响。单因素试验结果表明,单瓶平均产量分别在装瓶量1 000 g、灭菌前pH值 6.80、接种量35 mL、搔菌深度10 mm、搔菌补水量10 mL时达到最大值;Plackett-Burman试验表明装瓶量、灭菌前pH和搔菌补水量是影响金针菇单瓶平均产量的关键因素;响应面优化法预测的最优化条件为培养基装瓶量1 004.05 g、灭菌前pH值6.83、搔菌补水量11.41 mL,金针菇单瓶平均产量为473.81 g;结合单因素试验及响应面预测,将验证试验设置为培养基装瓶量(1 000±5) g、灭菌前pH值(6.80±0.10)、搔菌补水量(11±1) mL、搔菌深度(10±2) mm、接种量(35±5) mL,金针菇单瓶平均产量为466.36 g,比对照组提高11.63 g,与预测值接近,相对误差为1.57%,试验设计符合生产需求。  相似文献   
942.
韦春强  唐赛春  李象钦  潘玉梅 《广西植物》2022,42(12):2056-2063
为了探讨大狼耙草的入侵风险,该文通过同质种植园实验,研究了不同养分水平下大狼耙草河北、江苏、江西和广西4个入侵种群在单种和各种群与近缘本地植物金盏银盘混种时的生长和竞争响应。结果表明:(1)单种时4个种群的株高、分枝数和总生物量在高养分下显著高于低养分下,繁殖比在低养分下显著高于高养分下(江苏种群除外); 混种时4个种群各生长参数的竞争响应在高养分下小于低养分下的。(2)各养分下,广西和江西种群的株高和总生物量显著高于河北种群,广西种群的分枝数最多[低、中和高养分下分别为(12±0.86)、(16.83±0.95)和(21.83±1.14)]; 河北种群的繁殖比在低养分 [(47.33±3.29)%]和高养分 [(25.74±2.82)%]下最高,且显著高于同养分下的广西种群 [低养分为(30.92±1.78)%和高养分为(19.77±1.22)%]。中养分下,河北种群总生物量的竞争响应(-0.51±0.04)显著大于广西种群(-0.35±0.06),繁殖生物量的竞争响应(-0.46±0.03)也显著大于广西种群(-0.28±0.07)。综上表明,高养分提高大狼耙草的生长和竞争能力,生长和竞争能力在种群间有差异,养分增加和入侵种群间基因流可能会潜在地提高大狼耙草的入侵风险,该研究结果有助于预测入侵植物的入侵风险。  相似文献   
943.
丛枝菌根(arbuscular mycorrhizal, AM)真菌是一类能够与绝大多数陆地植物形成共生关系的土壤真菌, 其根外菌丝可以侵染不同植物根系且可以进行菌丝融合, 从而形成丛枝菌根网络(arbuscular mycorrhizal networks, AMNs)。AMNs可以在植物之间转运水分及营养元素如碳(C)、氮(N)、磷(P)等, 最近研究表明AMNs还可以在植物遭受环境胁迫时向邻近植物传递防御信号, 对周围植物起到“预警”作用。目前, 关于环境胁迫条件下AMNs介导的信号物质传递研究仍处于起步阶段, 许多问题亟待回答。该文首先回顾了目前有关AMNs介导的信号物质传递研究进展, 继而梳理了这一研究领域值得进一步探究的科学问题, 包括AMNs在植物间传递防御信号的可能途径及相关机制, AMNs介导的信号传递对菌根共生体系的可能影响, 以及AMNs研究中常用的技术及其发展, 最后讨论了AMNs介导的信号物质传递在作物保护等方面的可能应用。  相似文献   
944.
摘要 目的:探讨外周血单核细胞(PBMC)中CCAAT/增强子结合蛋白同源蛋白(CHOP)、核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)、S100A8/A9 信使核糖核酸(mRNA)表达水平与脓毒症患者炎症反应和预后的关系。方法:选取2020年1月~2022年1月新疆维吾尔自治区人民医院收治的170例脓毒症患者为脓毒症组,另选取同期68名健康体检者为对照组。采用酶联免疫吸附法检测血清白介素(IL)-6、IL-10、IL-17、IL-23、转化生长因子-β(TGF-β)水平,实时荧光定量PCR(qRT-PCR)法检测PBMC中CHOP、NLRP3、S100A8/A9 mRNA表达水平,比较脓毒症组与对照组上述指标差异。采用Pearson/Spearman相关系数分析脓毒症患者PBMC中CHOP、NLRP3、S100A8/A9 mRNA表达水平与炎症因子水平的相关性。脓毒症患者根据28d预后差异分为死亡组和存活组,收集临床资料,采用多因素Logistic回归分析脓毒症患者预后的影响因素。结果:脓毒症组PBMC中CHOP、NLRP3、S100A8/A9 mRNA相对表达量和血清IL-6、IL-10、IL-17、IL-23、TGF-β水平均明显高于对照组(P<0.05)。Pearson/Spearman相关性分析显示,脓毒症患者PBMC中CHOP、NLRP3、S100A8/A9 mRNA表达水平与血清IL-6、IL-10、IL-17、IL-23、TGF-β水平均呈正相关(P<0.05)。不同预后脓毒症患者比较,死亡组年龄大于存活组,脓毒性休克、多器官功能障碍综合征(MODS)、ICU住院时间≥10 d、机械通气时间≥3 d患者比例、脓毒症相关器官衰竭评估(SOFA)评分、血乳酸、血清IL-6、IL-10、IL-17、IL-23、TGF-β水平以及PBMC中CHOP、NLRP3、S100A8/A9 mRNA相对表达量均高于存活组,而氧合指数低于存活组(P<0.05)。多因素Logistic回归分析显示,校正其他因素后,PBMC中CHOP mRNA、NLRP3 mRNA、S100A8/A9 mRNA表达水平升高是脓毒症患者预后不良的危险因素(P<0.05)。结论:脓毒症患者PBMC中CHOP、NLRP3、S100A8/A9 mRNA呈高表达,且表达水平与炎症反应及患者预后密切相关。  相似文献   
945.
《遗传学报》2022,49(8):704-714
The phytohormone jasmonate plays a pivotal role in various aspects of plant life, including developmental programs and defense against pests and pathogens. A large body of knowledge on jasmonate biosynthesis, signal transduction as well as its functions in diverse plant processes has been gained in the past two decades. In addition, there exists extensive crosstalk between jasmonate pathway and other phytohormone pathways, such as salicylic acid (SA) and gibberellin (GA), in co-regulation of plant immune status, fine-tuning the balance of plant growth and defense, and so on, which were mostly learned from studies in the dicotyledonous model plants Arabidopsis thaliana and tomato but much less in monocot. Interestingly, existing evidence suggests both conservation and functional divergence in terms of core components of jasmonate pathway, its biological functions and signal integration with other phytohormones, between monocot and dicot. In this review, we summarize the current understanding on JA signal initiation, perception and regulation, and highlight the distinctive characteristics in different lineages of plants.  相似文献   
946.
947.
As a result of field tests in Bulgaria and Hungary, cis‐2‐isopropenyl‐l‐methylcyclobutane ethanol (racemic grandisol) is reported for the first time as an attractant for Bothynoderes affinis (Schrank) (Coleoptera: Curculionidae, Lixinae), a member of the pest weevil complex of sugar beet. Dose–response experiments in the field using Csalomon TAL (modified pitfall) traps (Plant Protection Institute, CAR HAS, Budapest, Hungary) showed that catches of B. affinis adults increased with increasing attractant dose. In a subsequent experiment studying the effect of trap color (white, blue, yellow, fluorescent yellow, and transparent) all traps with the lure caught more than non‐baited control traps, and the highest number of adults was recorded in transparent and yellow baited traps. Trap color had a significant effect on the number of B. affinis females captured. Transparent TAL traps baited with 1–10 mg grandisol applied on rubber dispensers are recommended for the detection and monitoring of B. affinis. In addition to the target species, 17 other Lixinae species were captured during the field experiments, demonstrating for the first time the possible role of grandisol in the chemical communication systems of some of these species. A second locality of Lixus punctiventris Boheman (Lixinae, Lixini) in Bulgaria is reported. TAL traps baited with grandisol might be a useful tool for surveying Lixinae diversity in different biotopes.  相似文献   
948.
The presence of multiple foot types has been used to explain the variability of foot structure observed among healthy adults. These foot types were determined by specific static morphologic features and included rectus (well aligned hindfoot/forefoot), planus (low arched), and cavus (high arched) foot types. Unique biomechanical characteristics of these foot types have been identified but reported differences in segmental foot kinematics among them has been inconsistent due to differences in neutral referencing and evaluation of only select discrete variables. This study used the radiographically-indexed Milwaukee Foot Model to evaluate differences in segmental foot kinematics among healthy adults with rectus, planus, and cavus feet based on the true bony alignment between segments. Based on the definitions of the individual foot types and due to conflicting results in previous literature, the primary study outcome was peak coronal hindfoot position during stance phase. Additionally, locally weighted regression smoothing with alpha-adjusted serial t-test analysis (LAAST) was used to compare these foot types across the entire gait cycle. Average peak hindfoot inversion was −1.6° ± 5.1°, 6.7° ± 3.5°, and 13.6° ± 4.6°, for the Planus, Rectus, and Cavus Groups, respectively. There were significant differences among all comparisons. Differences were observed between the Rectus and Planus Groups and Cavus and Planus Groups throughout the gait cycle. Additionally, the Planus Group had a premature peak velocity toward coronal varus and early transition toward valgus, likely due to a deficient windlass mechanism. This assessment of kinematic data across the gait cycle can help understand differences in dynamic foot function among foot types.  相似文献   
949.
Mansonic schistosomiasis is a neglected disease transmitted by Biomphalaria spp. snails. Understanding what happens inside the intermediate host is important to develop more efficient ways of reducing schistosomiasis prevalence. Our purpose was to characterize metabolic and immunological changes in Biomphalaria glabrata 24 h after exposure to Schistosoma mansoni. For this purpose, proteins were extracted from snails’ whole tissue with Tris-Urea buffer and digested with tripsin. Mass spectrometry was performed and analyzed with MaxQuant and Perseus software. Also, the hemolymph of five snails 24 h post exposure was collected, and the numbers of hemocytes, levels of urea, uric acid, nitric oxide, calcium, glycogen and alanine and aspartate aminotransferases activities were assessed. Snails were also dissected for measurement of glycogen content in the cephalopodal region and gonoda-digestive gland complex. Globin domain proteins were found to be up-regulated; also the number of circulating hemocytes was significantly higher after 24 h of exposure to the parasite. NO levels were higher 24 h post exposure. Several proteins associated with energy metabolism were found to be up-regulated. Glycogen analysis showed a significant decrease in the gonad-digestive gland complex glycogen content. We found several proteins which seem to be associated with the host immune response, most of which were up-regulated, however some were down-regulated, which may represent an important clue in understanding B. glabrata – S. mansoni compatibility.  相似文献   
950.
The objective of this non-randomized trial was comparison of two-year changes in dynamic corneal response (DCR) between 18 mW/cm2 (5- min) and 9 mW/cm2 (10-min) cross-linking (CXL) protocols, using novel stiffness parameters and correlating them to clinical indices. The two groups were evaluated before and 2 years after the procedure using Corvis ST (Oculus Optikgeräte GmbH, Germany) and DCR parameters such as deformation amplitude ratio at 1 mm and 2 mm (DA ratio-1 mm and DA ratio-2 mm) and integrated radius and stiffness parameters at A1 (SP-A1). Two-year follow-up was completed for 16 of the 30 eyes in the 5-min group and 21 of the 25 eyes in the 10-min group; data from those who were lost to follow-up was not included in the analyses. Mean age at baseline was 21.7 ± 4.9 and 21.5 ± 5.2 years in the 5- and 10-min groups, respectively (P = 0.895). At 2 years after CXL, in the 5-min group, the reduction in integrated radius (−1.12 ± 1.27 mm, P = 0.003) was significant, and the increase in SP-A1 (7.11 ± 14.86 mmHg/mm, P = 0.075) was borderline, while in the 10-min group, the decrease in DA ratio-2 mm (−0.43 ± 0.58, P = 0.003) and integrated radius (−1.89 ± 1.72 mm, P < 0.001), and increase in SP-A1 (7.67 ± 10.92 mmHg/mm, P = 0.004) were significant. In both groups, the strongest and significant correlation was observed between DCR parameters and changes in radius of curvature. In conclusion, results indicated corneal strengthening with both protocols especially with the 9 mW/cm2. Corvis ST indices can provide “in vivo” biomechanical evidence on the efficacy of CXL that may occur prior to clinical indices.  相似文献   
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