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991.
我国新型职业农民培训模式评价研究--基于AHP-Fuzzy模型 总被引:1,自引:0,他引:1
我国现有新型职业农民培训模式可以分为企业培训、专业机构培训、示范教育和学校教育4种模式。农村实际情况不同,选择的农民培训模式也应不同。该文在对4种培训模式进行比较的基础上,运用AHP-Fuzzy建立了新型职业农民培训模式评价指标模型,较好的解决了农民培训模式选择困境。 相似文献
992.
青枯菌潜伏浸染对花生的影响 总被引:2,自引:0,他引:2
用青枯菌对20个花生品种进行人工接种,研究了青枯菌潜伏侵染对花生根系、根瘤数、生物产量及结实性状的影响。结果表明,青枯菌潜伏侵染对花生生长发育有普遍的抑制作用,不同花生品种对潜伏浸染的反应存在广泛差异。 相似文献
993.
994.
对南海北部沿岸及东海南部9个不同地理群体的长鳍篮子鱼(Siganus canaliculatus)进行遗传多样性及遗传结构分析。484条DNA D-loop 序列分析结果显示:序列长度约 828bp,包含57个变异位点,92个单倍型;所有群体总的单倍型多样性指数(Hd)和核苷酸多样性指数(π)分别为0.80798和0.00405;群体内的遗传距离 0.00386~0.00532,群体间的遗传距离 0.00383~0.00482,群体间的分化指数为-0.01935~0.00759,各种分组的AMOVA分析均显示群体内变异比例超过100%;Fu"s Fs检验值为显著负值(-25.53678,p<0.01),核苷酸错配分布图呈单峰,吻合度检验数值较小且不显著,这些结果均提示长鳍篮子鱼可能经历过种群扩张事件,推测扩张时间约在4.74万年~1.18万年前。综上,南海北部沿岸及东海南部9个长鳍篮子鱼群体间不存在显著的地理结构和谱系结构,可划归一个管理单元进行种质资源保护。 相似文献
995.
Xiongjun Liu Xue Yang David T. Zanatta Manuel Lopes‐Lima Arthur E. Bogan Alexandra Zieritz Shan Ouyang Xiaoping Wu 《水产资源保护:海洋与淡水生态系统》2020,30(5):1000-1011
- The freshwater mussel (Unionida) fauna of the Yangtze River is among the most diverse on Earth. In recent decades, human activities have caused habitat degradation in the river, and previous studies estimated that up to 80% of the mussel species in the Yangtze River are Threatened or Near Threatened with extinction. However, a comprehensive and systematic evaluation of the conservation status of this fauna has yet to be completed.
- This study evaluated the conservation status of the 69 recognized freshwater mussel species in the middle and lower reaches of the Yangtze River, using the criteria published by the International Union for Conservation of Nature (IUCN). A new method for prioritizing species for conservation was then developed and applied termed Quantitative Assessment of Species for Conservation Prioritization (QASCP), which prioritizes species according to quantifiable data on their distribution and population status, life history, and recovery importance and potential.
- IUCN assessments showed that 35 (51%) species in the study region are Threatened or Near Threatened (11 Endangered, 20 Vulnerable, 4 Near Threatened). In addition, 16 species (23%) could not be assessed owing to data deficiency. Key threats to the freshwater mussel biodiversity of the Yangtze River include pollution, habitat loss and fragmentation, loss of access to host fish, and overharvesting of mussels and their host fish. The genera Aculamprotula, Gibbosula, Lamprotula, Pseudodon, Ptychorhynchus, and Solenaia were identified as particularly threatened.
- Data availability allowed QASCP assessment of 44 species. Only Solenaia carinata, regionally Endangered under IUCN criteria, achieved the highest QASCP rank, i.e. First Priority. The five species assessed as Second Priority were considered either regionally Endangered (one), Vulnerable (three), or Data Deficient (one) under IUCN criteria. The 23 Third Priority species were assessed as regionally Endangered (two), Vulnerable (15), Near Threatened (two), or Least Concern (four).
996.
Shuang–Huang–Lian (SHL), a traditional Chinese formula containing Lonicerae japonicae flos (LJF), Scutellariae radix (SR) and Forsythiae fructus (FF), is commonly used to treat acute upper respiratory tract infection, acute bronchitis and light pneumonia. Forsythoside A is one of the main active ingredients in Forsythiae fructus, a key herb in SHL. In the present study, effects of different compositions in SHL on the in vitro metabolism in Sprague–Dawley rat liver microsomes of forsythoside A were investigated. The observations from Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA that forsythoside A may be the substrates of CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3, UGT1A1 and UGT1A9; Chlorogenic acid may be the substrates of CYP3A4, CYP2C9, CYP1A2, CYP2C19, UGT1A6, UGT1A3 and UGT1A1; Baicalin may be the substrates of CYP3A4, CYP2C19, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; Baicalein may be the substrates of CYP3A4, CYP2E1 and UGT1A6. It was also found that the residue of forsythoside A in SHL, FF + LJF and FF + SR was greatly increased compared with that in FF in Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA, which indicated that the metabolism of forsythoside A in SHL may be influenced by chlorogenic acid in LJF acting on the CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3 and UGT1A1; baicalin in SR acting on the CYP3A4, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; baicalein acting on the CYP3A4 and UGT1A6 respectively. 相似文献
997.
Triptolide ameliorates Crohn's colitis is associated with inhibition of TLRs/NF-κB signaling pathway
Growing evidence suggests that TLRs/NF-κB signaling pathway plays a critical role in the pathogenesis of Crohn's disease (CD). We have reported that triptolide, an active component from Tripterygium wilfordii Hook, showed therapeutic activity in IL-10-deficeint (IL-10−/−) mice, a murine CD model. However the full mechanisms of action of this agent in CD remain largely unknown. We hypothesized that triptolide would ameliorate the experimental colitis by inhibiting TLRs/NF-κB signaling pathway. We found TLR2 and TLR4 were upregulated in IL-10−/− mice, triptolide inhibited the TLRs/NF-κB signaling pathway in vivo. In addition, triptolide in vitro was able to downregulate the TLRs/NF-κB pathway in cultured colonic explants from CD patients. Our results confirm the therapeutic effect of triptolide in experimental colitis, and suggest it as a promising compound for CD treatment. These findings also support the possibility that targeted inhibition of TLR signaling pathway is an approach deserving further investigation as a therapeutic strategy for CD. 相似文献
998.
春小麦籽粒蛋白质含量与农艺性状的相关性研究 总被引:2,自引:0,他引:2
为了给专用小麦的相关研究提供依据,从疆内外引入了26个春小麦的品种,田间观察测定各品种的农艺性状以及籽粒蛋白质含量,对各个农艺性状以及籽粒蛋白质含量进行了相关分析和通径分析.结果表明:穗长与单株粒数呈显著正相关,穗叶距与单株粒数、穗长与穗叶距、芒长与穗长呈显著负相关,单株粒数与单株穗数、株高与穗叶距、容重与千粒重、籽粒蛋白质含量与千粒重呈极显著正相关,籽粒蛋白质含量与单株穗数、单株粒数呈极显著负相关.对籽粒蛋白质含量贡献最大的为千粒重,穗叶距、容重、株高与籽粒蛋白质含量的直接通径系数为正相关,对籽粒蛋白质含量有一定的贡献.而芒长、穗长、单株穗数、单株粒数与籽粒蛋白质含量的相关系数和通径系数均为负数,它们之间的增长是异向的. 相似文献
999.
Haifeng Chen Zhihui Shan Aihua Sha Baoduo Wu Zhonglu Yang Shuilian Chen Rong Zhou Xinan Zhou 《Euphytica》2011,179(3):485-497
Stem strength is one of the major influencing factors of lodging in soybean [Glycine max (L.) Merr.] as well as other crops. To identify quantitative trait loci (QTL) associated with stem strength and related traits
in soybean, a recombinant inbred line (RIL) population consisting of 165 lines derived from Zhongdou No. 29 × Zhongdou No.
32 was used in 3 years. Significant positive correlations were found among the four traits (stem strength, stem diameter,
number of nodes, root dry weight). A linkage map spanning 1,240.7 cM was constructed using 245 SSR (simple sequence repeat)
markers and a phenotypic marker (leaflet shape). By composite interval mapping and two-round strategy of QTL meta-analysis,
32 consensus QTL and 19 unique QTL were identified, respectively. Of eight pleiotropic unique QTL, two QTL (uq.A2-2 and uq.A2-3) located at the intervals of 23.2–26.8 and 38.5–42.4 cM on linkage group A2, respectively, were associated with all the four
traits. Additive × environment (ae) interaction effects, epistasis (aa) and epistasis × environment (aae) interaction effects
of QTL were detected as well. The results provide useful information for further genetic studies on stem strength of soybean. 相似文献
1000.