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981.
Bao  G. Z.  Tang  W. Y.  Zhou  S. J.  Liu  B. J.  Wu  Z. Z.  Jin  D. X.  Bian  W. J.  Zhu  S. N. 《Russian Journal of Plant Physiology》2020,67(3):529-537
Russian Journal of Plant Physiology - To explore the physiological response characteristics of plant photosynthesis under acid precipitation stress (A stress), snow-melting agent stress (S stress),...  相似文献   
982.
Sun  Fan  Yang  WanChun  Du  ChaoLing  Chen  YangXi  FU  TianYi  Shi  DaNing 《Plasmonics (Norwell, Mass.)》2020,15(4):949-955
Plasmonics - Both the excitation wavelength and aspect ratio AR are key parameters controlling the refractive index sensitivity performances of plasmonic sensors of individual Au nanoplate dimmers....  相似文献   
983.
Association with arbuscular mycorrhizal fungi (AMF) can impact on plant water relations; mycorrhizal plants can exhibit increased stomatal conductance (gs) and root hydraulic conductance (normalized to root dry weight, Lo), and altered expression of aquaporins (AQP). Many factors regulate such responses; however, plant intraspecific diversity effects have yet to be explored. Twenty geographically diverse accessions of Medicago truncatula were inoculated with the AMF Funneliformis mosseae or mock‐inoculated, and grown under well‐watered conditions. Biomass, gs, shoot nutrient concentrations and mycorrhizal colonization were measured in all accessions, and Lo and gene expression in five accessions. The diverse accessions varied in physiology and gene expression; some accessions were also larger or had higher gs when colonized by F. mosseae. In the five accessions, Lo was higher in two accessions when colonized by AMF and also maintained within a much smaller range than the mock‐inoculated plants. Expression of MtPIP1 correlated with both gs and Lo, and when plants were more than 3% colonized, mycorrhizal colonization correlated with Lo. Accession and AMF treatments had profound effects on M. truncatula, including several measures of plant water relations. Correlations between response variables, especially between molecular and physiological variables, across genotypes, highlight the findings of this study.  相似文献   
984.
Conifers possess chemical and anatomical defences against tree‐killing bark beetles that feed in their phloem. Resins accumulating at attack sites can delay and entomb beetles while toxins reach lethal levels. Trees with high concentrations of metabolites active against bark beetle‐microbial complexes, and more extensive resin ducts, achieve greater survival. It is unknown if and how conifers integrate chemical and anatomical components of defence or how these capabilities vary with historical exposure. We compared linkages between phloem chemistry and tree ring anatomy of two mountain pine beetle hosts. Lodgepole pine, a mid‐elevation species, has had extensive, continual contact with this herbivore, whereas high‐elevation whitebark pines have historically had intermittent exposure that is increasing with warming climate. Lodgepole pine had more and larger resin ducts. In both species, anatomical defences were positively related to tree growth and nutrients. Within‐tree constitutive and induced concentrations of compounds bioactive against bark beetles and symbionts were largely unrelated to resin duct abundance and size. Fewer anatomical defences in the semi‐naïve compared with the continually exposed host concurs with directional differences in chemical defences. Partially uncoupling chemical and morphological antiherbivore traits may enable trees to confront beetles with more diverse defence permutations that interact to resist attack.  相似文献   
985.
Yang  Shih-Jyun  Ng  Chau-Yee  Wu  Ting-Shu  Huang  Po-Yen  Wu  Yen-Mu  Sun  Pei-Lun 《Mycopathologia》2019,184(1):169-176
Mycopathologia - Phaeohyphomycosis is a term used to describe a heterogenous group of cutaneous and systemic mycotic infections caused by melanized fungi. Many fungi have been reported as pathogens...  相似文献   
986.
Zheng  Yafei  Wu  Yuyun  Liu  Ying  Guo  Zhirui  Bai  Tingting  Zhou  Ping  Wu  Jin  Yang  Qin  Liu  Zhengxia  Lu  Xiang 《Neurochemical research》2019,44(7):1549-1566

This study aimed to investigate the potential effects of gold nanoparticles (Au-NPs) on rat cortical neurons exposed to oxygen–glucose deprivation/reperfusion (OGD/R) and to elucidate the corresponding mechanisms. Primary rat cortical neurons were exposed to OGD/R, which is commonly used in vitro to mimic ischemic injury, and then treated with 5- or 20-nm Au-NPs. We then evaluated cell viability, apoptosis, oxidative stress, and mitochondrial respiration in these neurons. We found that 20-nm Au-NPs increased cell viability, alleviated neuronal apoptosis and oxidative stress, and improved mitochondrial respiration after OGD/R injury, while opposite effects were observed for 5-nm Au-NPs. In terms of the underlying mechanisms, we found that Au-NPs could regulate Akt signaling. Taken together, these results show that 20-nm Au-NPs can protect primary cortical neurons against OGD/R injury, possibly by decreasing apoptosis and oxidative stress, while activating Akt signaling and mitochondrial pathways. Our results suggest that Au-NPs may be potential therapeutic agents for ischemic stroke.

  相似文献   
987.
Xiao  Na  Zhang  Jun  Chen  Chao  Wan  Yanfang  Wang  Ning  Yang  Jing 《Mammalian genome》2019,30(9-10):276-288
Mammalian Genome - Increasing evidence shows that miRNAs play pivotal roles in cardiovascular diseases, including heart failure (HF). The aim of this study was to investigate the role of miR-129-5p...  相似文献   
988.
The axolotl, Ambystoma mexicanum, is used extensively for research in developmental biology, particularly for its ability to regenerate and restore lost organs, including in the nervous system, to full functionality. Regeneration in mammals typically depends on the healing process and scar formation with limited replacement of lost tissue. Other organisms, such as spiny mice (Acomys cahirinus), salamanders, and zebrafish, are able to regenerate some damaged body components. Blastema is a tissue that is formed after tissue injury in such organisms and is composed of progenitor cells or dedifferentiated cells that differentiate into various cell types during regeneration. Thus, identifying the molecules responsible for initiation of blastema formation is an important aspect for understanding regeneration. Introns, a major source of noncoding RNAs (ncRNAs), have characteristic sizes in the axolotl, particularly in genes associated with development. These ncRNAs, particularly microRNAs (miRNAs), exhibit dynamic regulation during regeneration. These miRNAs play an essential role in timing and control of gene expression to order and organize processes necessary for blastema creation. Master keys or molecules that underlie the remarkable regenerative abilities of the axolotl remain to be fully explored and exploited. Further and ongoing research on regeneration promises new knowledge that may allow improved repair and renewal of human tissues.  相似文献   
989.
For many taxa, including isomorphic haplodiplontic macroalgae, determining sex and ploidy is challenging, thereby limiting the scope of some population demographic and genetic studies. Here, we used double‐digest restriction site‐associated DNA sequencing (ddRAD‐seq) to identify sex‐linked molecular markers in the widespread red alga Agarophyton vermiculophyllum. In the ddRAD‐seq library, we included 10 female gametophytes, 10 male gametophytes, and 16 tetrasporophytes from one native and one non‐native site (N = 40 gametophytes and N = 32 tetrasporophytes total). We identified seven putatively female‐linked and 19 putatively male‐linked sequences. Four female‐ and eight male‐linked markers amplified in all three life cycle stages. Using one female‐ and one male‐linked marker that were sex‐specific, we developed a duplex PCR and tested the efficacy of this assay on a subset of thalli sampled at two sites in the non‐native range. We confirmed ploidy based on the visual observation of reproductive structures and previous microsatellite genotyping at 10 polymorphic loci. For 32 vegetative thalli, we were able to assign sex and confirm ploidy in these previously genotyped thalli. These markers will be integral to ongoing studies of A. vermiculophyllum invasion. We discuss the utility of RAD‐seq over other approaches previously used, such as RAPDs (random amplified polymorphic DNA), for future work designing sex‐linked markers in other haplodiplontic macroalgae for which genomes are lacking.  相似文献   
990.
Melatonin has been reported to have tumor-suppressive effects via comprehensive molecular mechanisms, and long non-coding RNAs (lncRNAs) may participate in this process. However, the mechanism by which melatonin affects the function of lncRNAs in triple-negative breast cancer (TNBC), the most aggressive subtype of breast cancer, is still unknown. Therefore, we aimed to investigate the differentially expressed mRNAs and lncRNAs in melatonin-treated TNBC cells and the interaction mechanisms. Microarray analyses were performed to identify differentially expressed mRNAs and lncRNAs in TNBC cell lines after melatonin treatment. To explore the functions and underlying mechanisms of the mRNAs and lncRNAs candidates, a series of in vitro experiments were conducted, including CCK-8, Transwell, colony formation, luciferase reporter gene, and RNA immunoprecipitation (RIP) assays, and mouse xenograft models were established. We found that after melatonin treatment, FUNDC1 and lnc049808 downregulated in TNBC cell lines. Knockdown of FUNDC1 and lnc049808 inhibited TNBC cell proliferation, invasion, and metastasis. Moreover, lnc049808 and FUNDC1 acted as competing endogenous RNAs (ceRNAs) for binding to miR-101. These findings indicated that melatonin inhibited TNBC progression through the lnc049808-FUNDC1 pathway and melatonin could be used as a potential therapeutic agent for TNBC.Subject terms: Breast cancer, Non-coding RNAs  相似文献   
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