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51.
经近五年的调查,总结出信阳地区经常发生和危害严重的十种鸡病的发病原因及防制措施,提出了常发鸡病的综合防制对策。 相似文献
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在对日本森林疗养文献查询与阅读的基础上,通过对相关文献的分析,将日本森林疗养研究分为森林疗养效益实证研究、森林疗养基地研究及自然体验活动研究三个方面内容进行阐述,并将日本森林疗养的概念、研究内容与我国的森林康养进行比较,最后对中国森林康养产业发展做出展望。 相似文献
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AIM: To investigate the effects of chronic hypoxia on the aggressiveness of MCF-7, a human breast cancer cell line, and the underlying mechanisms.METHODS: MCF-7 cells were cultured under hypoxia (1% O2, 5% CO2 and 94% N2) or control (95% O2 and 5% CO2) condition. The viability, proliferation, and invasion and migration abilities of the MCF-7 cells were determined by MTT assay, CCK-8 assay, cell counting, and cell invasion and migration assays. Anchorage-independent growth and the alteration of cellular polarization of the MCF-7 cells were tested by soft agar colony formation assay and Matrigel-3D culture assay, respectively. The effects of chronic hypoxia on the growth and metastasis of MCF-7 cells in vivo were investigated by xenograft in nude mice. The morphological changes of the MCF-7 cells were observed under an inverted microscope. Hypoxia-induced alterations in the levels of hypoxia inducible factor-1 (HIF-1) and phosphorylated glycogen synthase kinase-3β (p-GSK-3β) as well as epithelial-mesenchymal transition (EMT) molecules, such as E-cadherin, N-cadherin, vimentin, matrix metalloproteinase (MMP)-3 and MMP-9, were determined by Western blot.RESULTS: Chronic hypoxia significantly increased the viability, proliferation, and invasion and migration abilities of MCF-7 cells in vitro, enhanced the anchorage-independent growth, facilitated cellular polarization alteration in Matrigel-3D culture, and promoted cancer metastasis in vivo. Hypoxia up-regulated HIF-1, activated GSK-3β, down-regulated E-cadherin and increased the protein levels of N-cadherin, vimentin, MMP-3 and MMP-9. CONCLUSION: Chronic hypoxia enhances the aggressiveness of breast cancer cells probably through EMT. 相似文献
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[目的]为进一步开发石斛药用资源提供基础数据。[方法]将人宫颈癌细胞HelaS3和肝癌HepG2细胞用含10%新生小牛血清的RPMI-1640培养基在37℃和5%CO2条件下培养,比较了霍山石斛、铁皮石斛、金钗石斛和马鞭石斛水提物对HelaS3和HepG2细胞的体外抑制作用。[结果]4种石斛水提物对HelaS3细胞和HepG2细胞均有不同程度的抑制作用,且在所选浓度范围内对剂量和时间有依赖性。4种石斛水提物对HelaS3细胞的IC50分别是11.63、17.71、15.11和5.89 mg/ml;对HepG2细胞的IC50分别是10.40、22.95、3.80和17.76 mg/ml。显微观察显示,处理组的活细胞多呈红色,核呈固缩状或圆珠状,有明显的染色质凝集和细胞凋亡特征。[结论]剂量效应分析表明,对HelaS3细胞而言,马鞭石斛水提物抑瘤效果较好;对HepG2细胞而言,金钗石斛水提物抑瘤效果较好。 相似文献
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旅游精准扶贫助推贫困地区乡村振兴的思考 总被引:1,自引:1,他引:1
贫困地区精准脱贫是乡村振兴的重点难点和优先任务,旅游扶贫已经成为我国贫困地区乡村振兴的重要方式。推动旅游精准扶贫与乡村振兴的有机衔接,是实现贫困地区乡村振兴的有效途径。本文立足文献述评、调研认知与研究思考,探讨旅游精准扶贫在贫困地区乡村振兴中的主要作用、现实问题和推进途径。研究表明,旅游精准扶贫可以促进贫困地区乡村振兴已成为各方共识,同时也面临利益分配机制不合理、内生增长乏力、生态环境制约等诸多挑战,乡村旅游扶贫需精准识别发展乡村旅游所具备的资源、区位、市场等条件和可行性,将乡村振兴战略的思想和原则融入具体的旅游精准扶贫计划与行动之中。具体需要准确把握好适宜区域、实施主体、主导产业、资金来源和保障机制,创新乡村旅游扶贫的商业模式、聚合乡村旅游扶贫的智力资源、夯实乡村旅游扶贫的文化底蕴、坚守乡村旅游扶贫的绿色发展底线、优化乡村旅游扶贫管理和组织机制,进而从产业振兴、人才振兴、文化振兴、生态振兴和组织振兴等五个方面全方位精准有效地助推乡村振兴。 相似文献
60.
X.J. Fang * L.R. Jiang Hainan Institute of Tropical Agricultural Resources Sanya China Life College Xiamen University Xiamen Fujian China. 《分子植物育种》2007,5(2):209-210
Rice appearance trait is mainly mean grain length (GL), grain width (GW), ratio of length and width (L/W), chalkiness (CH) and transparence (TR). Appearance is the first impression, and rice appearance traits effect significantly the value of commodity. Hybrid rice is relatively low quality, especially on rice appearance quality,which restricts partially its extend and badly export of hybrid seed and rice in China.Shanyou 63, the most famous hybrid rice combination of China, could not be also sustainable application because of its poor qualities. In this studies, We attempt to improve appearance quality of the elite rice maintainer of Zhenshan 97B by using molecular approach of genomic interval targeted introgression. Three F2 populations were constructed to study the classical and molecular genetic of rice appearance traits, at the same time, molecular marker-asisted toimprove the main maintainer line, Zhenshan 97B were performed. There some following results:Three F2 populations were constructed based on crosses of Guangluai 4×Jiafuzhan (GJ popu.), Minghui 86×Jiafuzhan (MJ popu.) and Zhenshan 97B×Jiafuzhan (ZJ popu.). ZJ popu and GJ popu were produced to reconstruct the linkage maps related with rice appearance traits based on BSA, and detect QTL of target traits based on IM.In ZJ popu, 9 QTLs of target traits were detected. The interval, RM169~RM516 on Chromosome 5, was genetic locus of GW, L/W, CH and BW, and the explained variances were 10.9%, 14.9%, 12.0% and 14.2%, respectively.RM214 on chromosome 7, RM339 on chromosome 8 were genetic loci if CH and BW, and the explained variances were 9.4%, 10.0%, 11.0% and 12.1%. besides there is a genetic locus, RM347, of G/W on chromosome 3, and the explained varance was 10.3%. In GJ popu, 5 QTLs of rice appearance traits were detected. The interval, RM169-RM516 on Chromosome 5, were also the genetic loci of GW, CH and BW, and the explained variances were 9.0%, 12.5%, and 13.6%, respectively. RM264~RM80 on chromosome 8 was the genetic loci of GW amd L/W,and the explained variances were 14.7% and 13.4%. The genotypes of all QTLs, except RM214, from Jiafuzhan contributed to improving riee appearance traits.The research was to improve the rice appearance quality of Zhenshan 97B by introgressing QTLs of rice appearance traits from Jiafuzhan, a donor parent, by means of MAS in the process of recurrent backcrossing, 4 SSR markers were used to detect the target genotypes from donor parent, and 70 SSR primers to identify the genetic background of recurrent parent. Consequently, there were 19 target individuals in BC3, in which the mean value of GL, GW, L/W, CH and BW were 6.06±0.04mm, 2.50±0.02mm, 2.43±0.02, 29.5±2.7 and 29.4±2.7%, respectively,and the mean homologous degree (HD) to recurrent parent is up to 98.22%. Compared to Zhenshan 97B, GL, CH and BW decreased 0.17 mm, 34.9% and 34.5% respectively and however L/W increased 0.19. which accounted separately for 25.37%, 54.79%, 54.57% and 10.50% of thedifference of every trait between two parents. It is very luckly to find a individual, 13BC2-3BC3 line, whose GL, GW, G/W, CH and BW were 6.04 mm, 2.43 mm, 2.49,2.5% and 2.5% separately, There is very important signification for it to be used in hybrid rice breeding improving appearance traits. In the research, MAS efficiency of 3 loci (with 4 markers ) was 5.68% and coincident degree was 73.08%. 相似文献