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31.
32.
A Yersinia enterocolitica serotype 9 was isolated from pond water; Y. enterocolitica-like bacteria were also isolated from pond water and from three species of snails (Lymnaea palustris elodes, Helisoma sp., Oxyloma retusa) from the Edwin S. George Reserve in southeastern Michigan. There was evidence for biochemical stability among some of the organisms over a period of years. There also was evidence of transmission of these organisms to snails from the water.  相似文献   
33.
Rice is a major source of cadmium(Cd) intake for Asian people. Indica rice usually accumulates more Cd in shoots and grains than Japonica rice. However, underlying genetic bases for differential Cd accumulation between Indica and Japonica rice are still unknown. In this study, we cloned a quantitative trait locus(QTL) grain Cd concentration on chromosome 7(GCC7) responsible for differential grain Cd accumulation between two rice varieties by performing QTL analysis and map-based cloning. We found that the two GCC7 alleles, GCC7~(PA64s) and GCC7~(93-11), had different promoter activity of OsHMA3,leading to different OsHMA3 expression and different shoot and grain Cd concentrations. By analyzing the distribution of different haplotypes of GCC7 among diverse rice accessions, we discovered that the high and low Cd accumulation alleles, namely GCC7~(93-11) and GCC7~(PA64s), were preferentially distributed in Indica and Japonica rice,respectively. We further showed that the GCC7~(PA64s)allele can be used to replace the GCC7~(93-11) allele in the super cultivar 93-11 to reduce grain Cd concentration without adverse effect on agronomic traits. Our results thus reveal that the QTL GCC7 with sequence variation in the OsHMA3 promoter is an important determinant controlling differential grain Cd accumulation between Indica and Japonica rice.  相似文献   
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Formononetin is a natural isoflavone compound found mainly in Chinese herbal medicines such as astragalus and red clover. It is considered to be a typical phytooestrogen. In our previous experiments, it was found that formononetin has a two‐way regulatory effect on endothelial cells (ECs): low concentrations promote the proliferation of ECs and high concentrations have an inhibitory effect. To find a specific mechanism of action and provide a better clinical effect, we performed a structural transformation of formononetin and selected better medicinal properties for formononetin modifier J1 and J2 from a variety of modified constructs. The MTT assay measured the effects of drugs on human umbilical vein endothelial cell (HUVEC) activity. Scratch and transwell experiments validated the effects of the drugs on HUVEC migration and invasion. An in vivo assessment effect of the drugs on ovariectomized rats. Long‐chain non‐coding RNA for EWSAT1, which is abnormally highly expressed in HUVEC, was screened by gene chip, and the effect of the drug on its expression was detected by PCR after the drug was applied. The downstream factors and their pathways were analysed, and the changes in the protein levels after drug treatment were evaluated by Western blot. In conclusion, the mechanism of action of formononetin, J1 and J2 on ECs may be through EWSAT1‐TRAF6 and its downstream pathways.  相似文献   
36.
In the ageing skeleton, the balance of bone reconstruction could commonly be broken by the increasing of bone resorption and decreasing of bone formation. Consequently, the bone resorption gradually occupies a dominant status. During this imbalance process, osteoclast is unique cell linage act the bone resorptive biological activity, which is a highly differentiated ultimate cell derived from monocyte/macrophage. The erosive function of osteoclasts is that they have to adhere the bone matrix and migrate along it, in which adhesive cytoskeleton recombination of osteoclast is essential. In that, the podosome is a membrane binding microdomain organelle, based on dynamic actin, which forms a cytoskeleton superstructure connected with the plasma membrane. Otherwise, as the main adhesive protein, integrin regulates the formation of podosome and cytoskeleton, which collaborates with the various molecules including: c-Cbl, p130Cas, c-Src and Pyk2, through several signalling cascades cross talking, including: M-CSF and RANKL. In our current study, we discuss the role of integrin and associated molecules in osteoclastogenesis cytoskeletal, especially podosomes, regulation and relevant signalling cascades cross talking.  相似文献   
37.
Methionine restrictive diet may alleviate ischaemia/reperfusion (I/R)‐induced myocardial injury, but its underlying mechanism remains unclear. HE staining was performed to evaluate the myocardial injury caused by I/R and the effect of methionine‐restricted diet (MRD) in I/R mice. IHC and Western blot were carried out to analyse the expression of CSE, CHOP and active caspase3 in I/R mice and hypoxia/reoxygenation (H/R) cells. TUNEL assay and flow cytometry were used to assess the apoptotic status of I/R mice and H/R cells. MTT was performed to analyse the proliferation of H/R cells. H2S assay was used to evaluate the concentration of H2S in the myocardial tissues and peripheral blood of I/R mice. I/R‐induced mediated myocardial injury and apoptosis were partially reversed by methionine‐restricted diet (MRD) via the down‐regulation of CSE expression and up‐regulation of CHOP and active caspase3 expression. The decreased H2S concentration in myocardial tissues and peripheral blood of I/R mice was increased by MRD. Accordingly, in a cellular model of I/R injury established with H9C2 cells, cell proliferation was inhibited, cell apoptosis was increased, and the expressions of CSE, CHOP and active caspase3 were dysregulated, whereas NaHS treatment alleviated the effect of I/R injury in H9C2 cells in a dose‐dependent manner. This study provided a deep insight into the mechanism underlying the role of MRD in I/R‐induced myocardial injury.  相似文献   
38.
The case‐control study was designed to investigate the genetic effects of interferon‐gamma (IFN‐γ) rs2069727 and rs1861494 polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese Han population. Blood samples were collected from 108 AS patients and 110 healthy controls. IFN‐γ polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Hardy‐Weinberg equilibrium (HWE) test was performed in control group. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using chi‐square test to evaluate the association between AS susceptibility and IFN‐γ polymorphisms, and the results were adjusted by logistic regressive analysis. The frequency of rs2069727 CC genotype was much higher in cases than that in controls, suggested its significant association with increased AS risk (adjusted OR = 5.899, 95% CI = 1.563‐22.261; P = .009). In addition, C allele also showed close association with increased risk of AS (adjusted OR = 2.052, 95% CI = 1.286‐1.704, P  = 0 .003). While the genotype and allele frequencies of IFN‐γ rs1861494 polymorphism were not significantly different between patients and controls (P  > 0.05 for all), IFN‐γ rs2069727 polymorphism is significantly associated with increased AS risk in a Chinese Han Population.  相似文献   
39.
The lithium–sulfur (Li–S) battery is a next generation high energy density battery, but its practical application is hindered by the poor cycling stability derived from the severe shuttling of lithium polysulfides (LiPSs). Catalysis is a promising way to solve this problem, but the rational design of relevant catalysts is still hard to achieve. This paper reports the WS2–WO3 heterostructures prepared by in situ sulfurization of WO3, and by controlling the sulfurization degree, the structure is controlled, which balances the trapping ability (by WO3) and catalytic activity (by WS2) toward LiPSs. As a result, the WS2–WO3 heterostructures effectively accelerate LiPS conversion and improve sulfur utilization. The Li–S battery with 5 wt% WS2–WO3 heterostructures as additives in the cathode shows an excellent rate performance and good cycling stability, revealing a 0.06% capacity decay each cycle over 500 cycles at 0.5 C. By building an interlayer with such heterostructure‐added graphenes, the battery with a high sulfur loading of 5 mg cm?2 still shows a high capacity retention of 86.1% after 300 cycles at 0.5 C. This work provides a rational way to prepare the metal oxide–sulfide heterostructures with an optimized structure to enhance the performance of Li–S batteries.  相似文献   
40.
海岸带植物叶片的化学计量学特征及其影响因素可以为改善海岸带的生态环境提供理论依据。选取海南岛沿岸12个市(县)海岸带木麻黄防护林的木麻黄和周边沙滩上的藤本植物厚藤为研究对象,通过测定木麻黄与厚藤叶片中的碳(C)、氮(N)和磷(P)含量,分析两种植物叶片C、N和P的化学计量学特征及其差异,探究不同环境因子对两种植物叶片C、N、P含量、C:N、C:P和N:P的影响,以期寻找影响海岸带植被生长的主要限制因素。结果表明:海南岛木麻黄叶片C、N和P的平均含量分别是399.06±20.29、12.56±1.04、1.04±0.35 g·kg-1,C:N、C:P和N:P分别为32.04±2.82、420.65±121.27和12.92±3.21;厚藤叶片C、N和P的平均含量分别是364.31±30.20、12.84±1.96和2.06±0.64 g·kg-1,C:N、C:P和N:P分别为29.13±4.95、185.85±63.14和6.47±2.12。相关性分析结果表明:木麻黄叶片的N含量与年平均气温和年平均降水量呈显著正相关关系,P含量与年平均降水量呈极显著正相关关系,C:P和N:P与年平均降水量呈显著负相关关系;厚藤叶片C含量与年平均气温呈显著正相关,C:N与年平均降水量呈显著负相关。木麻黄叶片的N含量与10~20 cm土层的SOC呈显著负相关关系,C:N与10~20 cm土层的SOC呈显著正相关,C:P与0~10 cm土层的C:N呈显著正相关关系;厚藤叶片的C含量与10~20 cm土层的SOC呈显著负相关关系,P含量与0~10 cm土层的TN含量,N:P和10~20 cm的SOC含量呈正相关关系,C:N与0~10 cm土层的C:N呈显著正相关关系,C:P与0~10 cm的TN含量呈显著负相关关系而与0~10 cm土层的C:N呈极显著正相关关系,N:P与0~10 cm土层的TN含量呈显著负相关关系。研究结果表明海南岛海岸带植被叶片的碳氮含量较低,N可能是影响该区域植物生长的主要因子,同时,植被生长受到年平均气温、年平均降水量的共同影响,受土壤养分含量影响低,环境因子对不同类型的植物的影响并不相同。  相似文献   
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