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51.
口服他莫昔芬法建立ICR小鼠子宫腺肌病模型 总被引:2,自引:0,他引:2
目的使用口服他莫昔芬法建立ICR小鼠子宫腺肌病模型,并检测其病灶特征、动情周期、血管生成、子宫炎症等变化,以介绍和评价这一动物模型。方法新生ICR小鼠(15只)连续4 d滴喂他莫昔芬,并与同龄对照小鼠(15只)分别于42、85-95、135-145日龄处死,使用苏木素-伊红染色检测子宫病理改变;阴道脱落细胞法检测动情周期变化;免疫组化补体31(CD31)染色计算子宫微血管的密度、直径及所占面积比;逆转录-聚合酶链反应(RT-PCR)检测子宫缓激肽受体、神经激肽受体的基因表达。结果使用口服他莫昔芬法建立ICR小鼠子宫腺肌病模型的造模率为100%,且疾病严重程度随病程进展。部分给药小鼠可出现动情周期紊乱。85-95及135-145日龄给药小鼠子宫肌层微血管密度和面积比均高于对照小鼠(P〈0.05)。135-145日龄给药小鼠子宫缓激肽受体、神经激肽受体的基因表达较对照组明显升高(P〈0.05)。结论口服他莫昔芬法可方便、高效的建立腺肌病小鼠模型,出现腺肌病相关的血管生成、炎症状态、疼痛相关受体表达增高等特征,是研究腺肌病发生、发展的良好模型。 相似文献
52.
Pei Jie Xiong Lin Bao Pengjia Chu Min Yan Ping Guo Xian 《Probiotics and antimicrobial proteins》2021,13(3):873-884
Probiotics and Antimicrobial Proteins - Lactoferricin (Lfcin) is a potent antibacterial peptide derived from lactoferrin by pepsin hydrolysis. It was hypothesized that structural transformation of... 相似文献
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54.
烟草叶片发育过程中光合功能衰退与H_2O_2积累的关系 总被引:1,自引:0,他引:1
以烟草(NicotianatabacumL.cvNC89)为材料,研究了叶片发育过程中H2O2积累与叶绿体光合功能衰退、抗坏血酸-谷胱甘肽(AsA-GSH)循环的关联。结果表明,光合功能衰退过程中,各光合参数均表现为先缓慢后快速的下降趋势,核酮糖-1,5-二磷酸羧化酶(RuBPCase)活性下降较电子传递活性下降迅速,H2O2含量与叶绿素含量、光合速率、RuBPCase活性、抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)活性显著负相关。H2O2的定位染色也证实光合功能衰退与H2O2积累密切相关。APX和GR在光合功能可逆衰退阶段维持较高水平,不可逆衰退阶段下降稍快。烟草叶片光合功能衰退快于AsA-GSH循环运转的下调。 相似文献
55.
Haowei Ni Xiaoyan Jing Xian Xiao Na Zhang Xiaoyue Wang Yueyu Sui Bo Sun Yuting Liang 《The ISME journal》2021,15(9):2561
Understanding the effects of changing climate and long-term human activities on soil organic carbon (SOC) and the mediating roles of microorganisms is critical to maintain soil C stability in agricultural ecosystem. Here, we took samples from a long-term soil transplantation experiment, in which large transects of Mollisol soil in a cold temperate region were translocated to warm temperate and mid-subtropical regions to simulate different climate conditions, with a fertilization treatment on top. This study aimed to understand fertilization effect on SOC and the role of soil microorganisms featured after long-term community incubation in warm climates. After 12 years of soil transplantation, fertilization led to less reduction of SOC, in which aromatic C increased and the consumption of O-alkyl C and carbonyl C decreased. Soil live microbes were analyzed using propidium monoazide to remove DNAs from dead cells, and their network modulization explained 60.4% of variations in soil labile C. Single-cell Raman spectroscopy combined with D2O isotope labeling indicated a higher metabolic activity of live microbes to use easily degradable C after soil transplantation. Compared with non-fertilization, there was a significant decrease in soil α- and β-glucosidase and delay on microbial growth with fertilization in warmer climate. Moreover, fertilization significantly increased microbial necromass as indicated by amino sugar content, and its contribution to soil resistant C reached 22.3%. This study evidentially highlights the substantial contribution of soil microbial metabolism and necromass to refractory C of SOC with addition of nutrients in the long-term.Subject terms: Microbial ecology, Biodiversity 相似文献
56.
Li BH Yang XZ Li PD Yuan Q Liu XH Yuan J Zhang WJ 《Biochemical and biophysical research communications》2008,369(2):554-560
IL-4-induced Stat6 signaling is active in a variety of cell types and plays a role in cell proliferation/growth and resistance to apoptosis. Using EMSA, we identified differential IL-4/Stat6 activities in colorectal cancer cell lines, HT-29 being active Stat6high phenotype and Caco-2 being defective Stat6null phenotype, respectively. Active Stat6high HT-29 cells exhibited resistance to apoptosis by flowcytometry and aggressive metastasis by Transwell assay compared with defective Stat6null Caco-2 cells. Comparing one another using RT-PCR, Stat6high HT-29 cells expressed more mRNA of anti-apoptotic and pro-metastatic genes Survivin, MDM2, and TMPRSS4, while Stat6null Caco-2 cells expressed more mRNA of pro-apoptotic and anti-metastatic genes BAX, CAV1, and P53, respectively. This is the first study describing correlations of IL-4/Stat6 activities with apoptosis and metastasis in colon cancer. These findings, together with the observation of constitutive Stat6 activation in many human malignancies, suggest that Stat6 activities could be a biomarker for cancer cell’s invasive/metastatic capability. 相似文献
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59.
Li N Li X Zhang Y Wang T Xiao W 《Zeitschrift für Naturforschung. C, Journal of biosciences》2008,63(1-2):66-68
Flavonoids and organic acids were recommended in the literature as the main active constituents of Camptosorus sibiricus Rupr. Assay-guided fractionation led to the isolation of 9 flavonoids and 8 phenolic acids. All compounds were tested for DPPH scavenging activity, SOD-like and aldose reductase inhibition. Among them, compounds 1, 2, 3, 5, 6, 7, 8, 9, 11, 15 showed activities. The most active free radical scavenger and antioxidant was compound 8, while compound 1 exhibited strong inhibiting activity of aldose reductase. The structure-activity relation was dicussed briefly. 相似文献
60.
Bo Xian Jie Shen Weiyang Chen Na Sun Nan Qiao Dongqing Jiang Tao Yu Yongfan Men Zhijun Han Yuhong Pang Matt Kaeberlein Yanyi Huang Jing‐Dong J. Han 《Aging cell》2013,12(3):398-409
Caenorhabditis elegans is a leading model organism for studying the basic mechanisms of aging. Progress has been limited, however, by the lack of an automated system for quantitative analysis of longevity and mean lifespan. To address this barrier, we developed ‘WormFarm’, an integrated microfluidic device for culturing nematodes. Cohorts of 30–50 animals are maintained throughout their lifespan in each of eight separate chambers on a single WormFarm polydimethylsiloxane chip. Design features allow for automated removal of progeny and efficient control of environmental conditions. In addition, we have developed computational algorithms for automated analysis of video footage to quantitate survival and other phenotypes, such as body size and motility. As proof‐of‐principle, we show here that WormFarm successfully recapitulates survival data obtained from a standard plate‐based assay for both RNAi‐mediated and dietary‐induced changes in lifespan. Further, using a fluorescent reporter in conjunction with WormFarm, we report an age‐associated decrease in fluorescent intensity of GFP in transgenic worms expressing GFP tagged with a mitochondrial import signal under the control of the myo‐3 promoter. This marker may therefore serve as a useful biomarker of biological age and aging rate. 相似文献