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1.
高粱蚜灰色灾变长期预测模型   总被引:2,自引:1,他引:1  
张汝霖  周安定 《昆虫知识》1994,31(6):327-329
本文应用灰色系统灾变预测理论建立了吕梁地区高粱蚜发生量预测模型.  相似文献   
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RNA干扰作用研究进展   总被引:1,自引:0,他引:1  
RNA干扰 (RNAinterference ,RNAi)是指与内源性mRNA编码区某段序列同源的双链RNA分子 (double strandedRNA ,dsRNA)导入细胞时 ,该mRNA发生特异性的降解 ,导致基因表达的沉默。本文介绍RNAi作用的发现、机制和目前使用的产生RNAi的方法  相似文献   
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Pan YX  Ren AJ  Zheng J  Rong WF  Chen H  Yan XH  Wu C  Yuan WJ  Lin L 《Life sciences》2007,81(13):1042-1049
Hypoxic preconditioning (HPC) has been well demonstrated to have potent protective effects in many cell types; however, the mechanisms responsible for this phenomenon are not fully understood. Recently, glucose-regulated protein 78 (GRP78), an inducible molecular chaperon, was indicated to be associated with ischemic preconditioning. We hypothesized that HPC protects cardiomyocytes against hypoxia by inducing GRP78 in cultured neonatal rat cardiomyocytes. HPC was induced by exposing cardiomyocytes to brief hypoxia (1% O(2), 30 min) followed by reoxygenation. GRP78 was expressed constitutively in cultured cardiomyocytes and its expression was enhanced at 12 h, peaked at 24 h (207.3+/-23.6% of the baseline), and was sustained for up to 72 h after HPC. Twenty-four hours after HPC, the myocytes were subjected to prolonged hypoxia (1% O(2), 12 h). The lactic dehydrogenase (LDH) release and malondialdehyde (MDA) content were reduced, while cell viability and superoxide dismutase (SOD) activity were increased in the preconditioned cells compared with the non-HPC cells. The GRP78 protein level was higher in cells exposed to both HPC and hypoxia than in the cells exposed to HPC alone or hypoxia alone. Heat shock protein 70 (HSP70) was induced in parallel by late HPC. Transfection of GRP78 antisense oligonucleotides blocked GRP78 expression but not HSP70, resulting in attenuated cardioprotection afforded by late HPC. Furthermore, inducing GRP78 by gene transfer protected cardiomyocytes from hypoxic injury. These findings demonstrate that the induction of GRP78 partially mediates the late HPC, suggesting that GRP78 is a novel mechanism responsible for the late cytoprotection of HPC.  相似文献   
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1植物名称百里香(Thymus serpyllum var.mongolicus Ronn.)。2材料类别顶芽和腋芽。3培养条件(1)芽诱导培养基:MS基本培养基;(2)增殖培养基:MS 6-BA 1.5 mg·L~(-1)(单位下同) IBA 0.1 0.6%琼脂 3%蔗糖;(3)生根培养基:1/2MS IBA 0.5 0.7%琼脂 2%蔗糖。以上所有培养基均为pH 5.8~6.0,培养温度(24±2)℃,光  相似文献   
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用甲基敏感扩增多态性(MSAP)技术分析光暗条件下生长的大蒜DNA甲基化水平差异。结果表明,用8对引物组合扩增出343条带,完全一致的带型240条,不一致的103条。在不一致的条带中,光照条件下相同的47条带与黑暗条件下相同的带型有差异,与黑暗相比光照下出现的去甲基化带28条,有56条差异带在2个处理内个体间也有差异。总的趋势是光照引起大蒜DNA去甲基化。  相似文献   
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Jiang  Hui-Ning  Yun  Shuai-Ting  Wang  Bao-Xun  Zhang  Ming-Jing  Ma  Yu  Zhou  Yan-Xia 《Antonie van Leeuwenhoek》2022,115(6):773-782

A Gram-stain-positive, orange-pigmented, rod-shaped and flagellated bacterial strain T12T was isolated from wetland soil in Kunyu Mountain Wetland in Yantai, China. The strain was able to grow at 15–40 °C (optimum 37 °C), at 0.0–9.0% NaCl (optimum 2%, w/v) and at pH 5.5–9.0 (optimum 8.5). A phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain T12T is a member of the family Planococcaceae, sharing 97.6% and 97.1% sequence similarity with the type strains of Jeotgalibacillus salarius and Jeotgalibacillus marinus, respectively. Genome-based analyses revealed a genome size of 3,506,682 bp and a DNA G?+?C content of 43.7%. Besides, the genome sequence led to 55.0–74.6% average amino acid identity values and 67.8–74.7% average nucleotide identity values between strain T12T and the current closest relatives. Digital DNA-DNA hybridization of strain T12T with the type strains of Jeotgalibacillus proteolyticus and J. marinus demonstrated 19.0% and 20.3% relatedness, respectively. The chemotaxonomic analysis showed that the sole quinone was MK-7. The predominant cellular fatty acids were iso-C15:0, anteiso-C15:0, C16:1ω7c alcohol and iso-C14:0. The polar lipids consisted of an unidentified aminolipid, phosphatidylglycerol, diphosphatidylglycerol and two unidentified phospholipids. Based on the polyphasic characterization, strain T12T is considered to represent a novel species, for which the name Jeotgalibacillus aurantiacus sp. nov. is proposed. The type strain is T12T (=?KCTC 43296 T?=?MCCC 1K07171T).

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Peng  Li-Yang  Yin  Rui  Gao  Shu-Kun  Jiang  Hui-Ning  Liu  Xiao-Xiao  Ma  Yu  Zhou  Yan-Xia 《Antonie van Leeuwenhoek》2022,115(1):33-40

A Gram-stain-negative, wheat, rod-shaped, non-motile, non-spore forming, and facultatively anaerobic bacterium strain, designated as PIT, was isolated from saline silt samples collected in saltern in Yantai, Shandong, China. Growth was observed within the ranges 4–45 °C (optimally at 33 °C), pH 6.0–9.0 (optimally at pH 7.0) and 1.0–11.0% NaCl (optimally at 3.0%, w/v). Strain PIT showed highest 16S rRNA gene sequence similarity to Kangiella sediminilitoris BB-Mw22T (98.3%) and Kangiella taiwanensis KT1T (98.3%). The major cellular fatty acids (>?10% of the total fatty acids) were iso-C15:0 (52.7%) and summed featured 9 (iso-C17:1ω9c/C16:0 10-methyl, 11.8%). The major polar lipids identified were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine and phosphatidylglycerol. The major respiratory isoprenoid quinone was Q-8. The G?+?C content of the genomic DNA was 45.8%. Average Nucleotide Identity values between whole genome sequences of strain PIT and next related type strains supported the novel species status. Based on physiological, biochemical, chemotaxonomic characteristics and genomic analysis, strain PIT is considered to represent a novel species within the genus Kangiella, for which the name Kangiella shandongensis sp. nov. is proposed. The type strain is PIT (=?KCTC 82509 T?=?MCCC 1K04352T).

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