燕麦β-葡聚糖降血糖性能研究进展

本文从三个方面综述了燕麦β-葡聚糖降血糖性能研究进展。首先从食品血糖生成指数(glycemic index,GI)、餐后血糖、空腹血糖和α-淀粉酶活性等方面阐述了燕麦β-葡聚糖降血糖的功效,进而介绍了燕麦β-葡聚糖的结构因素——分子量和含量,以及食品加工过程对其降血糖功效的影响,最后综述了燕麦β-葡聚糖几种可能的降血糖机制,以期对后续研究提供参考。     

离子交换纤维对麦田土壤铅污染的修复效果

为探讨土壤Pb污染的治理方法,通过盆栽试验,比较了离子交换纤维的两种不同放置方式(分层放置与混匀放置)对麦田土壤Pb污染的修复效果。结果表明,在土壤1 000 mg·kg~(-1) Pb污染水平下,Pb污染处理(T1:Pb胁迫;T2:Pb+在土壤中分三层放置纤维;T3:Pb+在土壤中混匀剪碎的纤维)的土壤pH值、总有机碳含量较对照(CK:未添加Pb和离子交换纤维)有所降低。在小麦成熟期,T2、T3处理下土壤和植株各部位的Pb含量均低于T1处理,其中T3处理变化显著;T2、T3处理中纤维吸附的Pb含量则分别达到115.01和128.26 mg·kg~(-1)。T2、T3处理的Pb富集系数低于T1处理及CK。由此说明,离子交换纤维能够有效吸附土壤中的Pb,降低Pb从土壤向植株的转运能力,且离子交换纤维混匀放置方式的修复效果较好。     

Effects of platelet-rich plasma on chondrocyte apoptosis and NLRP3/IL-1β signaling pathway in rabbits with osteoarthritis

AIM To explore the effect of platelet-rich plasma (PRP) on rabbit osteoarthritis and its possible mechanism. METHODS The rabbits with knee osteoarthritis were prepared and then divided into model group, sodium hyaluronate (SH) group and PRP group, and another sham operation group was set up, with 6 rabbits in each group. The gross morphological changes of rabbit cartilage were observed. HE staining was used to evaluate the pathomorphological changes of the cartilage. TUNEL staining was used to detect the apoptosis of chondrocytes. The expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/interleukin-1β （IL-1β） signaling pathway-related molecules was observed by immunohistochemical staining, and the protein levels of caspase-3, Bcl-2 and Bax were determined by Western blot. Chondrocytes were isolated and processed according to grouping, and the NLRP3 and IL-1β levels of the cells were measured by ELISA. RESULTS Compared with sham operation group, Pelletier score, Mankin score, chondrocyte apoptotic rate, the positive protein expression rates of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in model group were increased significantly (P<0.05), while the protein expression of Bcl-2 was decreased significantly (P<0.05). Compared with model group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in SH group and PRP group were decreased significantly (P<0.05), while the protein expression of Bcl-2 was increased significantly (P<0.05). In PRP group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax were lower than those in SH group, while the protein expression of Bcl-2 was higher than that in SH group (P<0.05). Compared with control group, the expression of NL?RP3 and IL-1β in MCC950 (NLRP3 ihibitor) group were significantly reduced (P<0.05), the expression of NLRP3 in eucalyptol (IL-1β inhibitor) group was not significantly changed (P>0.05), and the expression of IL-1β was significantly reduced (P<0.05). CONCLUSION Platelet-rich plasma promotes the repair of cartilage in osteoarthritis rabbits, which has better effect than SH. The mechanism may be related to the inhibition of NLRP3/IL-1β pathway and the reduction of chondrocyte apoptosis.     

柠檬新品种‘黄绣球’

‘黄绣球’是从沃尔卡姆柠檬芽变培育而来的柠檬新品种。树姿呈开张状,春梢刺少且刺长度适中;嫩叶中间绿色,外缘淡红色;部分成熟叶外缘黄色,中间绿色。果实圆形且表面光滑,幼果果面呈黄绿相间带状条纹,转色期绿色部分变为橙色,果面橙黄相间,完全成熟后果面以黄色为主,留红色斑点。具有较高的观赏价值,适合制作盆景。     

重庆市不同规模灌区农灌水有效利用系数测算与对比研究

通过对重庆市不同规模灌区农田灌溉用水有效利用系数计算结果的比较研究,对出现的中型灌区农田灌溉用水有效利用系数大于小型灌区的结果进行合理性分析,并为重庆市农田灌溉用水有效利用系数的进一步提高,提出相关建议,为政府相关部门的科学决策提供参考.综合考虑重庆的地形、气候、土壤等因素.根据选定灌区的实测数据,采用首尾测算法计算2017年重庆市不同规模灌溉农田灌溉水的有效利用系数,采用单因素和主成分分析法,分析影响农田灌溉水有效灌溉系数的主要因素. 1)通过测算, 2017年重庆市中型灌区农田灌溉水有效利用系数为0.499,小型灌区为0.487,推算全市为0.495; 2)在影响农田灌溉水有效利用系数的主要因素中,当地的节水工程和管理状况所占的比例大于自然因素; 3)中型灌区在节水工程的投资、管理和维护等方面均优于小型灌区; 4)自然因素中,降水量对农田灌溉水有效利用系数具有一定的负面影响.     

家兔中microRNA的研究进展

microRNA(miRNA)是一类内源性非编码单链RNA分子,通过与靶基因mRNA配对以指导其功能表达,在动物中扮演着重要的基因调节作用。研究表明,miRNA广泛参与调节动物的生长发育、生殖调控、新陈代谢和疾病发生等生命过程。本文综述了miRNA在家兔中的研究,例如促进肌肉细胞增殖分化、调节脂肪代谢和影响疾病发生等,探讨miRNA在家兔中的研究现状和发展方向,旨在为家兔遗传育种与繁殖提供理论依据。     

田园综合体建设初期土地利用效益综合评价——以鲁家村为例

以鲁家村田园综合体项目为例,构建田园综合体土地利用效益评价指标体系,综合运用层次分析法和变异系数法组合确定指标权重,并从社会效益、经济效益、生态效益3方面对其土地利用效益进行综合分析,以期为田园综合体建设提供借鉴。结果显示:鲁家村田园综合体建设初期土地利用效益评价中,社会效益、经济效益、生态效益所占比重依次减小。鲁家村土地利用效益在田园综合体规划实施后有较大提升,社会效益、经济效益于2016—2017年增幅较大,2017—2018年增幅较小;生态效益在2016—2018年总体呈现稳定小幅增长。总的来看,鲁家村田园综合体建设对当地社会发展、经济提升、生态保护等均有正向影响,且在短期内社会效益、经济效益显著,而生态效应提升不明显。