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101.
Owing to its diverse sex types, the cucumber plant has been studied widely as a model for sex determination. In addition to environmental factors and plant hormones, three major genes—F/f, M/m, and A/a—regulate the sex types in the cucumber plant. By combining the bulked segregant analysis (BSA) and the sequence-related amplified polymorphism (SRAP) technology, we identified eight markers linking to the M/m locus. Among them, the two closely linked SRAP markers flanking the M/m locus were the co-dominant marker ME1EM26 and the dominant marker ME1EM23. Further, the co-dominant marker ME8SA7 co-segregated with the M/m locus. With the chromosome walking method using the cucumber genomic bacterial artificial chromosome (BAC) library, we successfully developed a co-dominant SCAR marker S_ME1EM23 from the ME1EM23 sequence. Along with the other two co-dominant SCAR markers S_ME1EM26 and S_ME8SA7 (developed from ME1EM26 and ME8SA7, respectively) in a larger segregating population (900 individuals), the M/m locus was mapped between S_ME1EM26 (5.4 cM) and S_ME1EM23 (0.7 cM), and S_ME8SA7 co-segregated with it. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Z. Li and J. Pan contribute equally to this article.  相似文献   
102.
Mitochondrial dynamics—fission and fusion—are associated with ischaemic heart disease (IHD). This study explored the protective effect of vagal nerve stimulation (VNS) against isoproterenol (ISO)‐induced myocardial ischaemia in a rat model and tested whether VNS plays a role in preventing disorders of mitochondrial dynamics and function. Isoproterenol not only caused cardiac injury but also increased the expression of mitochondrial fission proteins [dynamin‐related peptide1 (Drp1) and mitochondrial fission protein1 (Fis‐1)) and decreased the expression of fusion proteins (optic atrophy‐1 (OPA1) and mitofusins1/2 (Mfn1/2)], thereby disrupting mitochondrial dynamics and leading to increase in mitochondrial fragments. Interestingly, VNS restored mitochondrial dynamics through regulation of Drp1, Fis‐1, OPA1 and Mfn1/2; enhanced ATP content and mitochondrial membrane potential; reduced mitochondrial permeability transition pore (MPTP) opening; and improved mitochondrial ultrastructure and size. Furthermore, VNS reduced the size of the myocardial infarction and ameliorated cardiomyocyte apoptosis and cardiac dysfunction induced by ISO. Moreover, VNS activated AMP‐activated protein kinase (AMPK), which was accompanied by phosphorylation of Ca2+/calmodulin‐dependent protein kinase kinase β (CaMKKβ) during myocardial ischaemia. Treatment with subtype‐3 of muscarinic acetylcholine receptor (M3R) antagonist 4‐diphenylacetoxy‐N‐methylpiperidine methiodide or AMPK inhibitor Compound C abolished the protective effects of VNS on mitochondrial dynamics and function, suggesting that M3R/CaMKKβ/AMPK signalling are involved in mediating beneficial effects of VNS. This study demonstrates that VNS modulates mitochondrial dynamics and improves mitochondrial function, possibly through the M3R/CaMKKβ/AMPK pathway, to attenuate ISO‐induced cardiac damage in rats. Targeting mitochondrial dynamics may provide a novel therapeutic strategy in IHD.  相似文献   
103.
王润  丁圣彦  卢训令  宋博 《生态学报》2017,37(7):2225-2236
在农业景观中,传粉昆虫的生存繁衍与半自然生境的面积大小有关。集约化生产方式使半自然生境比例逐渐减少,农田比例不断增加,随着景观简化梯度的变化(农田比例逐渐增大),传粉昆虫群落多样性将会发生怎样的变化?选择黄河中下游典型农区巩义市为研究区域,采用诱捕盘法(Pan traps)进行农田、林地的传粉昆虫取样,以21个样点作为景观简化梯度(农田比例范围5%—86%)的呈现,基于每个样点的传粉昆虫多度和丰富度变化来探究景观简化对传粉昆虫多样性的影响。结果显示:区内累计捕获传粉昆虫39660头,优势类群包括双翅目(Diptera)、膜翅目(Hymenoptera)、鞘翅目(Coleoptera)等。采用逐步回归分析及线性拟合后发现景观简化程度与传粉昆虫多度和丰富度呈显著负相关(P0.05);景观简化对传粉昆虫类群间的影响也是有差异的,其中对鞘翅目多度的影响最为密切(R~2=0.27),同时对膜翅目和双翅目也有较大影响(R~2=0.14、R~2=0.11),景观简化与鳞翅目多度呈正相关;随景观简化的程度加深,农田生境中膜翅目多度呈显著下降趋势(P0.05),而林地中膜翅目多度变化不明显。在未来的景观规划中,应着重考虑传粉昆虫中鞘翅目类群的栖息地变化及食物资源状况。依据研究结果建议林地生境中应注重保护现有的自然植被群落,在人工林中可以种植一定面积的蜜粉源植物;农田生境内对杂草群落、半自然生境斑块进行合理规划的基础上,还可以种植线性景观植物作为传粉昆虫的食物源。  相似文献   
104.
1‐Phenyl‐5‐p‐tolyl‐1H‐1, 2, 3‐triazole (PPTA) was a synthesized compound. The result of acute toxicities to mice of PPTA by intragastric administration indicated that PPTA did not produce any significant acute toxic effect on Kunming strain mice. It exhibited the various potent inhibitory activities against two kinds of bananas pathogenic bacteria, black sigatoka and freckle, when compared with that of control drugs and the inhibitory rates were up to 64.14% and 43.46%, respectively, with the same concentration of 7.06 mM. The interaction of PPTA with human serum albumin (HSA) was studied using fluorescence polarization, absorption spectra, 3D fluorescence, and synchronous spectra in combination with quantum chemistry and molecular modeling. Multiple modes of interaction between PPTA and HSA were suggested to stabilize the PPTA–HSA complex, based on thermodynamic data and molecular modeling. Binding of PPTA to HSA induced perturbation in the microenvironment around HSA as well as secondary structural changes in the protein.  相似文献   
105.
Long noncoding RNAs (lncRNAs) play roles in the development and progression of many cancers; however, the contributions of lncRNAs to human gallbladder cancer (GBC) remain largely unknown. In this study, we identify a group of differentially expressed lncRNAs in human GBC tissues, including prognosis‐associated gallbladder cancer lncRNA (lncRNA‐PAGBC), which we find to be an independent prognostic marker in GBC. Functional analysis indicates that lncRNA‐PAGBC promotes tumour growth and metastasis of GBC cells. More importantly, as a competitive endogenous RNA (ceRNA), lncRNA‐PAGBC competitively binds to the tumour suppressive microRNAs miR‐133b and miR‐511. This competitive role of lncRNA‐PAGBC is required for its ability to promote tumour growth and metastasis and to activate the AKT/mTOR pathway. Moreover, lncRNA‐PAGBC interacts with polyadenylate binding protein cytoplasmic 1 (PABPC1) and is stabilized by this interaction. This work provides novel insight on the molecular pathogenesis of GBC.  相似文献   
106.
107.
山西南部脱皮榆群落生态特征及其物种多样性的研究   总被引:4,自引:0,他引:4  
选择脱皮榆群落分布较为集中的霍山、中条山等2个地段,设计7个样地,用样方法进行调查,共做样方585个。分析了脱皮榆群落的种类组成、区系特点、群落外貌、垂直结构等群落学特征,并对该群落的环境概况进行分析,计测了不同地段群落的重要值指标和不同层次上的Shannon-Wiener指数、Simpson指数和Pielou指数。结果表明,脱皮榆主要分布于海拔1100-1650m的中海拔山地。群落组成种类约156种,北温带分布属占优势,显示了脱皮榆群落具有北温带性质。高位芽和一年生植物种类多,显示了脱皮榆群落分布区域夏季水热条件良好,冬季漫长、寒冷、干旱的气候特点。乔木层平均高度约13m,多样性指数H为1.0260一1,5907;灌木层H值0.9983—2.4478;草本层H值为0.9047—3.0621。研究为脱皮榆可持续利用和保护提供了有益的参考。  相似文献   
108.
山西霍山罂粟科植物花粉形态   总被引:3,自引:0,他引:3  
杨瑞林  魏学智  毕润成 《广西植物》2003,23(3):231-232,I003,I004
利用光学显微镜和扫描电子显微镜对山西霍山罂粟科白屈菜属白屈菜、紫堇属延胡索、角茴香属角茴香、秃疮花属秃疮花 4种的花粉形态进行了观察和比较研究 ,以上 4种花粉差异大。角茴香花粉粒近球形 ,具合沟 ;延胡索花粉粒长球形 ,表面纹饰较光滑 ;白屈菜花粉粒长球形或近球形 ;秃疮花花粉粒近球形。角茴香花粉表面纹饰为刺状纹和细网状纹的复合纹 ,白屈菜花粉表面纹饰为细网状纹和颗粒状纹的复合纹 ,秃疮花花粉表面纹饰为细颗粒状纹。延胡索、白屈菜、秃疮花花粉粒的萌发沟均为三沟 ,但沟的形态均不相同  相似文献   
109.
A full-length cDNA encoding sucrose synthase was isolated from the tropical epiphytic orchid Oncidium Goldiana. The cDNA is 2829 bp in length containing an open reading frame of 2447 bp encoding 816 amino acids with a predicted molecular mass of 93.1 kDa. The deduced amino acid sequence of O . Goldiana sucrose synthase ( Osus ) shares more than 80% identity with those from other monocotyledonous plants. The sucrose synthase gene was demonstrated to encode a functional sucrose synthase protein by expression as recombinant protein in Escherichia coli . The Osus mRNA is present in all the tissues analysed, with the highest levels in strong sinks such as developing inflorescence and root tips. Incubation with sucrose or glucose resulted in a significant increase in the steady-state Osus mRNA levels in root tips and mature leaves in a similar pattern to maize Sus1 . Expression of the Osus mRNA in mature leaves was markedly enhanced by anaerobic conditions and elevated CO2. The expression pattern and regulation of the gene suggest that the sucrose synthase plays an important role in the growth and development of the tropical epiphytic orchid O . Goldiana.  相似文献   
110.
黄河三角洲盐碱土壤中AM真菌的初步调查   总被引:13,自引:0,他引:13  
2000年3月-2001年2月对黄河三角洲盐碱土壤中5种优势植物柽柳(Tamarix chinensis),芦苇(Phragmites communis),碱蓬(Suaeda glauca),獐毛(Aeluropus littralis var.sinensis) 和刺儿菜(Cirsium setosum)根围内丛枝菌根(arbuscular mycorrhiza,AM)真菌进行了长期定点调查,结果表明,AM真菌在这5种植物根围土壤内都有分布,但多样性较低,尤其在冬季,AM真菌种的丰度和孢子密度分别在夏季降低了18.0%和61.6%,不同深度土层中AM真菌的分布存在诸多差异。  相似文献   
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