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91.
Insufficient available phosphorus in soil has become an important limiting factor for the improvement of yield and quality in soybean. The mining of QTLs and candidate genes controlling soybean phosphorus utilization related traits is a necessary strategy to solve this problem. In this study, 11 phosphorus utilization related traits of a natural population of 281 typical soybean germplasms and a recombinant inbred line(RIL) population of 270 lines were evaluated under different phosphorus condit...  相似文献   
92.
金鑫  何翠  曾旭 《农学学报》2022,12(1):65-69
通过简述魔芋生长环境需求特性,总结魔芋庭院栽培、净作栽培、大田间套作栽培、林下栽培、轮作栽培及保护地栽培等栽培模式研究进展,分析各种栽培模式的优缺点。提出了今后应从广泛开展魔芋种质资源收集、鉴定、评价与利用,构建魔芋间套作、轮作栽培新模式,提高魔芋种植全程机械化、自动化水平,扩大魔芋种植范围,创建有机栽培模式等方面改进和丰富魔芋栽培模式。  相似文献   
93.
为提高江苏河蟹主产区产量预测能力,以此为基础制定科学合理的河蟹养殖发展规划,本研究对河蟹主产区附近设立的7个观测台站2013—2017年的气象数据和该区产量数据进行了采集,利用插值法补足少量缺失值,通过主成分分析选取了最能代表江苏省河蟹主产区特点的5个主成分作为研究对象建立BP神经网络,探索其用于江苏省河蟹主产区产量随气象因子变化的规律。结果表明,通过PCA主成分分析降维处理后数据的大部分特点能被BP神经网络学习到,预测值与真实之间的相关系数为0.82267,具备一定的模拟气象因子数据与产量之间的关系的能力。  相似文献   
94.
High yields of wheat are mainly obtained through a high level of nitrogen and irrigation supplementation.However,excessive nitrogen and irrigation supplication increase the risk of lodging.The main objectives of this work were to clarify the capacity of lodging resistance of wheat in response to nitrogen and irrigation,as well as to explore the effective ways of improving lodging resistance in a high-yield wheat cultivar.In this study,field experiments were conducted in the 2015–2016 and 2016–20...  相似文献   
95.
本试验旨在研究枸芪多糖对育肥猪肠黏膜免疫调控的关键基因,阐明其对肠黏膜免疫功能的可能作用机理.选用80~90日龄的健康育肥母猪180头,随机分为2组,每组6个重复,每个重复15头猪.对照组饲喂基础饲粮,试验组在基础饲粮中添加0.1%的枸芪多糖,试验期90 d.采集育肥猪的空肠肠段,提取RNA后进行转录组测序分析差异免疫...  相似文献   
96.
为明确农田栽培人参土壤养分及综合肥力状况,为人参种植合理选地改土提供参考,对农田栽培人参14个主要县市种植区42份样品的14项土壤养分指标进行测试,采用主成分分析和模糊数学隶属度函数模型,并利用土壤肥力综合指标值(IFI)对土壤肥力状况进行综合评价.结果 表明:土壤有机质、全氮、全磷、碱解氮、速效钾及微量元素有效态铁、...  相似文献   
97.
JIN Liang  WANG Bai-ren  JU Gong 《园艺学报》2000,16(12):1327-1330
Fractalkine has been recognized as the first member of the fourth chemokine family recently and its receptor, CX3CR1, was ident ified afterwards. This pair of ligand/receptor play important roles in the migration and adhesion of peripheral leukocyte through different ways. They are also likely to be related to the embryogenesis and regeneration of several organs and may possess some functions in the central nervous system.  相似文献   
98.
AIM: Studying the mechanism of protective role of metallothionein(MT) in hypoxic preconditioning(HPC) of cultivated rat cardiomyocytes. METHODS:Using the model of hypoxia/reoxygenation of cultivated rat cardiomyocytes. Determining the contents of MT, malonyldialdehyde (MDA)-metabolism product of lipid peroxidation and the activities of Na+-K+ATPase, Ca2+-Mg2+ATPase of cardiomyocytes 24h after HPC, also determining the relevant changes after using MT antibody. RESULTS: After 24 h in HPC, the contents of MT and activities of Na+-K+ATPase, Ca2+-Mg2+ATPase were obviously higher than those in the control and hypoxia/reoxygenation(P<0.05), and the contents of MDA were decreased remarkedly (P<0.01). Then after using MT antibody, the activities of two enzyme were progressively decreased and the contents of MDA were significantly higher than those in the control and MT antibody-free groups(P<0.01). CONCLUSION: HPC may induce excessive synthesis of MT, and MT can protect myocardial reoxygenation injury by eliminating lipid peroxidation and rising the activities of Na+-K+ATPase and Ca2+-Mg2+ATPase.  相似文献   
99.
AIM:To determine the relationship between ischemia, hypoxia and the production of vascular endothelial growth factor in rat myocardium and its basic mechanism. METHODS:(1) 28 Wistar rats were randomly divided into 4 groups: group A, normal control;group B, 1 day's acute myocardial infarction;group C, 3 day's acute myocardial infarction;group D, 7 day's acute myocardial infarction. (2) Rat cardiac myocytes cultured were primarily divided into some groups, hypoxia incubated 24 hours; PMA groups, hypoxia incubated 24 hours with PKC activator (PMA), A 0 ng/mL; B 10 ng/mL; C 100 ng/mL; D 1 000 ng/mL; Chelerythrine groups, hypoxia incubated 24 hours with PKC inhibitor (chelerythrine), A 0 nmol/L; B 10 nmol/L. (3) By computer scanned and quantitated, vascular endothelial growth factor (VEGF) protein was detected with immunohistochemical technique. RESULTS:The longer time of ischemia and hypoxia was, the higher the VEGF production.The relat ionship was found between the time of ischemia or hypoxia and the production of VEGF.The product ion of VEGF protein was further promoted by PMA with different concentrat ion, decreased by chelerythrine.CONCLUSION: Ischemia or hypoxia strongly stimulated the production of VEGF in myocardium, which played an important role in autoprotecting of ischemic or hypoxic myocardium. Hypoxia-induced PKC activation is one kind of basic mechanisms in this course.  相似文献   
100.
AIM: To study the activation effects of maize pollen polysaccharides(PPM) on human thoracic cavity macrophage (hTMΦ). METHODS: Activities of lactate dehydrogenase(LDH) and acid phosphatase (ACP) in the hTMΦ were detected by automatic biochemical analyzer, and the level of tumor necrosis factor alpha(TNF-α) and interleukin-6(IL-6) in the hTMΦ was analyzed by radioimmunoassay, after hTMΦ were cultured with 0.312, 0.625, 1.250, 2.500, 5.000 mg/mL PPM-RPMI 1640 for 24 and 48 hours in vitro. RESULTS: The activities of LDH and ACP increased in the hTMΦ induced by PPM, and the levels of TNF-α and IL-6 in the hTMΦ induced by PPM increased markedly too. And the induced expression effect of TNF-α and IL-6 is associated with the concentration of PPM, and time for PPM inducing. CONCLUSION: PPM can induce cytokines secretion in hTMΦ, and activate hTMΦ in vitro.  相似文献   
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