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排序方式: 共有9246条查询结果,搜索用时 15 毫秒
41.
Zhang Hao Qing Zhao Xue Qiang Chen Yi Ling Zhang Ling Yu Shen Ren Fang 《Plant and Soil》2019,439(1-2):293-308
Plant and Soil - Biocrusts are important functional units in dryland ecosystems. Regarded as ecosystem engineers, cyanobacteria in biocrusts contribute several major physico-chemical and biological... 相似文献
42.
Liu T Yu H Zhang C Lu M Piao Y Ohba M Tang M Yuan X Wei S Wang K Ma A Feng X Qin S Mukai C Tsuji A Jin F 《Applied and environmental microbiology》2012,78(13):4752-4754
A novel rutin-α-L-rhamnosidase hydrolyzing α-L-rhamnoside of rutin, naringin, and hesperidin was purified and characterized from Aspergillus niger DLFCC-90, and the gene encoding this enzyme, which is highly homologous to the α-amylase gene, was cloned and expressed in Pichia pastoris GS115. The novel enzyme was classified in glycoside-hydrolase (GH) family 13. 相似文献
43.
Xiaoqin Zhang Guoqiang Chen Qingsheng Xue Buwei Yu 《Cellular and molecular neurobiology》2010,30(6):885-890
Injury to the peripheral nervous system can lead to spontaneous pain, hyperalgesia and allodynia. Previous studies have shown
sprouting of Aβ-fibres into lamina II of the spinal cord dorsal horn after nerve injury and the formation of new synapses
by these sprouts. β-Catenin and menin as synaptogenic factors are critically involved in synapse formation. However, the roles
of β-catenin and menin in neuropathic pain are still unclear. Using Western blot analysis we investigated the changes of β-catenin
and menin in the spinal dorsal horn after unilateral spared nerve injury (SNI). We demonstrated an increase in both β-catenin
and menin protein levels in the ipsilateral spinal dorsal horn at days 1 and 3 following spared nerve injury (P < 0.05). These increases were associated with changes in paw withdrawal threshold to mechanical stimuli and weight bearing
deficit suggestive of pain behavior and spontaneous ongoing pain respectively. However, the injury-associated increases in
β-catenins and menins levels returned to control levels at day 14. In conclusion, these results indicate that peripheral nerve
injury induces upregulation of β-catenins and menins in the dorsal horn of the spinal cord, which may contribute to the development
of chronic neuropathic pain. Antagonists of these molecules may serve as new therapeutic agents. 相似文献
44.
P2X7 receptor inhibition attenuated sympathetic nerve sprouting after myocardial infarction via the NLRP3/IL‐1β pathway 下载免费PDF全文
Hesheng Hu Xiaolu Li Mei Xue Wenjuan Cheng Ye Wang Xinran Li Na Yang Yugen Shi Suhua Yan 《Journal of cellular and molecular medicine》2017,21(11):2695-2710
Mounting evidence supports the hypothesis that inflammation modulates sympathetic sprouting after myocardial infarction (MI). The myeloid P2X7 signal has been shown to activate the nucleotide‐binding and oligomerization domain‐like receptor family pyrin domain‐containing 3 (NLRP3) inflammasome, a master regulator of inflammation. We investigated whether P2X7 signal participated in the pathogenesis of sympathetic reinnervation after MI, and whether NLRP3/interleukin‐1β (IL‐1β) axis is involved in the process. We explored the relationship between P2X7 receptor (P2X7R) and IL‐1β in the heart tissue of lipopolysaccharide (LPS)‐primed naive rats. 3′‐O‐(4‐benzoyl) benzoyl adenosine 5′‐triphosphate (BzATP), a P2X7R agonist, induced caspase‐1 activation and mature IL‐1β release, which was further neutralized by a NLRP3 inhibitor (16673‐34‐0). MI was induced by coronary artery ligation. Following infarction, a marked increase in P2X7R was localized within infiltrated macrophages and observed in parallel with an up‐regulation of NLRP3 inflammasome levels and the release of IL‐1β in the left ventricle. The administration of A‐740003 (a P2X7R antagonist) significantly prevented the NLRP3/IL‐1β increase. A‐740003 and/or Anakinra (an IL‐1 receptor antagonist) significantly reduced macrophage infiltration as well as macrophage‐based IL‐1β and NGF (nerve growth factor) production and eventually blunted sympathetic hyperinnervation, as assessed by the immunofluorescence of tyrosine hydroxylase (TH) and growth‐associated protein 43 (GAP 43). Moreover, the use of Anakinra partly attenuated sympathetic sprouting. This indicated that the effect of P2X7 on neural remodelling was mediated at least partially by IL‐1β. The arrhythmia score of programmed electric stimulation was in accordance with the degree of sympathetic hyperinnervation. In vitro studies showed that BzATP up‐regulated secretion of nerve growth factor (NGF) in M1 macrophages via IL‐1β. Together, these data indicate that P2X7R contributes to neural and cardiac remodelling, at least partly mediated by NLRP3/IL‐1β axis. Therapeutic interventions targeting P2X7 signal may be a novel approach to ameliorate arrhythmia following MI. 相似文献
45.
Ouyang G Chen Z Cai XJ Song BA Bhadury PS Yang S Jin LH Xue W Hu DY Zeng S 《Bioorganic & medicinal chemistry》2008,16(22):9699-9707
Fourteen title compounds, 1-substituted-5-substitutedphenylthio-4-pyrazolaldoxime ester derivatives 4a-4n, were synthesized from the starting material 1-substitutedphenyl-3-methyl-5-substitutedphenylthio-4-pyrazolaldoximes 3 by treatment with acyl chloride. The synthesized compounds were characterized by physical constants, and the structures of the title compounds were further confirmed by IR, 1H NMR, 13C NMR and elemental analysis. The bioassay results showed that title compounds possessed weak to good anti-TMV bioactivity with 4l showing significant enhancement of disease resistance in tobacco leaves with high affinity for TMV CP. 相似文献
46.
Jia Xu Fengmei Lian Linhua Zhao Yufeng Zhao Xinyan Chen Xu Zhang Yun Guo Chenhong Zhang Qiang Zhou Zhengsheng Xue Xiaoyan Pang Liping Zhao Xiaolin Tong 《The ISME journal》2015,9(3):552-562
The gut microbiota is hypothesized to have a critical role in metabolic diseases, including type 2 diabetes (T2D). A traditional Chinese herbal formula, Gegen Qinlian Decoction (GQD), can alleviate T2D. To find out whether GQD modulates the composition of the gut microbiota during T2D treatment, 187 T2D patients were randomly allocated to receive high (HD, n=44), moderate (MD, n=52), low dose GQD (LD, n=50) or the placebo (n=41) for 12 weeks in a double-blinded trial. Patients who received the HD or MD demonstrated significant reductions in adjusted mean changes from baseline of fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) compared with the placebo and LD groups. Pyrosequencing of the V3 regions of 16S rRNA genes revealed a dose-dependent deviation of gut microbiota in response to GQD treatment. This deviation occurred before significant improvement of T2D symptoms was observed. Redundancy analysis identified 47 GQD-enriched species level phylotypes, 17 of which were negatively correlated with FBG and 9 with HbA1c. Real-time quantitative PCR confirmed that GQD significantly enriched Faecalibacterium prausnitzii, which was negatively correlated with FBG, HbA1c and 2-h postprandial blood glucose levels and positively correlated with homeostasis model assessment of β-cell function. Therefore, these data indicate that structural changes of gut microbiota are induced by Chinese herbal formula GQD. Specifically, GQD treatment may enrich the amounts of beneficial bacteria, such as Faecalibacterium spp. In conclusion, changes in the gut microbiota are associated with the anti-diabetic effects of GQD. 相似文献
47.
膜翅目精子结构研究新进展 总被引:3,自引:0,他引:3
根据观察,膜翅目昆虫精子由顶体,精核,中部,尾部四个主要部分构成。顶体具顶体丝,中部具轴丝,中部与精核间具线粒体衍生物。本文同时对膜翅目,分别隶属12个科,10个总科中的2个亚目昆虫精子的顶体、精核、线粒体衍生物、轴丝等结构的研究状况进行概括,并应用精子结构特征对上述类群的系统发育状况进行讨论。 相似文献
48.
广东地区三种木本植物抗大气污染能力的比较 总被引:9,自引:1,他引:9
研究了工业污染区(佛山市小塘镇五星WX)和相对清洁区(广州华南植物园BG)生长的3种木本植物光叶山矾(Symplocos lancifolia)、银柴(Aporosa chinensis)和窿缘桉(Eucalyptus exserta)叶片对酸碱缓冲能力的差别。工业污染区3种植物的细胞液pH均比相对清洁区的低,光叶山矾与银柴对酸和碱的缓冲能力强于窿缘桉。用外源NaHSO3处理,植物叶片的光合放氧、Fv/Fm、Fv/Fo和ФPsⅡ都有不同程度的下降。其中,窿缘桉下降的幅度最大,说明其抗大气污染的能力不如光叶山矾和银柴,同时也证明了用缓冲能力作为一种评价植物抗污能力的指标具有一定的科学性。 相似文献
49.
Background
Tumor necrosis factor-α (TNF-α) 308 G/A gene polymorphism has been reported to be associated with susceptibility to silicosis. However, the relevant study results are still inconsistent.Objective and Methods
A meta-analysis was performed in order to drive a more precise estimation of the relationship between TNF-α-308 G/A gene polymorphism and susceptibility to silicosis. Electronic databases were searched and nine separate studies were included. The pooled odds ratios (ORs) and the corresponding 95% confidence internal (CI) were calculated by a fixed effect model.Results
A total of 1267 cases and 1214 controls were included. In the overall analysis, significantly increased silicosis risk was found (for GA+AA vs. GG OR=1.45, 95%CI: 1.20-1.760, P=1.58E4; for GA vs. GG: OR=1.53, 95%CI=1.25-1.86, P=3.11E5; for A allele vs. G allele: OR=1.27, 95%CI=1.08-1.50, P= 0.004). In the subgroup analysis, significantly increased silicosis risk was also found among Asians (for GA+AA vs. GG: OR=1.63, 95%CI=1.27-2.08, P=1.01E4), for GA vs. GG: OR=1.71, 95%CI=1.33-2.20, P=3.44E5), for A allele vs. G allele: OR=1.45, 95%CI=1.17-1.80, P=0.001). However, no significantly increased risk was found among non-Asians for all genetic models.Conclusions
TNF-α-308 G/A polymorphism might lead to an increased risk of silicosis susceptibility, especially for Asians. However, further studies with large sample sizes should be conducted to confirm the association. 相似文献50.