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991.
葡萄是新疆生产建设兵团林果业的主导产业之一,兵团葡萄在新疆和全国占有重要地位。本研究在基于层次分析法的鲜食葡萄生态适宜性评价、综合比较优势指数的鲜食葡萄比较优势分析和成本收益的市场需求分析基础上,开展的兵团鲜食葡萄种植布局综合评价,研究结果表明:鲜食葡萄优良种植区域集中在天山北麓、伊犁河谷与吐哈盆地的农四师、农六师、农八师、农十三师等为鲜食葡萄重点生产地区,评价结果与生产实际总体相一致,为兵团鲜食葡萄种植布局优化提供可量化的参考依据。  相似文献   
992.
“食品微生物学”是一门综合性的学科,涉及到基础微生物学,食品微生物学,工业微生物学和医学微生物学等领域,知识涉及面广,课程综合性强,对人们的日常生活影响大。将食品微生物学打造成课程思政教育的前沿阵地尤为重要。因此,本文首先系统性的介绍了将专业课程与思政教育相结合的重要性和必要性。接着笔者重点对食品微生物学中所蕴含的思政元素进行了深入解析,将一些典型案例与课程中的知识点有机融合。最后从改革教学方法,创新教学理念和提高教师队伍的思政意识等方面来阐述了如何才能实现课程思政建设的高效性。本文能够为后续的专业课程如何进行思政建设提供参考,更重要的是能够为教师如何从专业课的知识点中挖掘思政元素提供借鉴和启发。  相似文献   
993.
The aim of present study was to evaluate whether diets supplemented with dihydroartemisinin (DHA) could alleviate intestinal inflammatory injury in weaned piglets with intrauterine growth retardation (IUGR). Twelve normal birth weight (NBW) piglets and 12 piglets with IUGR were fed a basal diet (NBW-CON and IUCR-CON groups), and another 12 piglets with IUGR were fed the basal diet supplemented with DHA at 80 mg/kg (IUGR-DHA group) from 21 to 49 d of age. At 49 d of age, 8 piglets with similar body weight in each group were sacrificed. The jejunal and ileal samples were collected for further analysis. The results showed that IUGR impaired intestinal morphology, increased intestinal inflammatory response, raised enterocyte apoptosis and reduced enterocyte proliferation and activated transmembrane toll-like receptor 4 (TLR4)/nucleotide-binding and oligomerization domain (NOD)/nuclear factor-κB (NF-κB) signaling pathway. Dihydroartemisinin inclusion ameliorated intestinal morphology, indicated by increased villus height, villus height-to-crypt depth ratio, villus surface area and decreased villus width of piglets with IUGR (P < 0.05). Compared with NBW piglets, IUGR piglets supplemented with DHA exhibited higher apoptosis index and caspase-3 expression, and lower proliferation index and proliferating cell nuclear antigen expression in the intestine (P < 0.05). Dihydroartemisinin supplementation attenuated the intestinal inflammation of piglets with IUGR, indicated by increased concentrations of intestinal inflammatory cytokines and lipopolysaccharides (P < 0.05). In addition, DHA supplementation down-regulated the related mRNA expressions of TLR4/NOD/NF-κB signaling pathway and upregulated mRNA expressions of negative regulators of TLR4 and NOD signaling pathway in the intestine of piglets with IUGR (P < 0.05). Piglets in the IUGR-DHA group showed lower protein expressions of TLR4, phosphorylated NF-κB (pNF-κB) inhibitor α, nuclear pNF-κB, and higher protein expression of cytoplasmic pNF-κB in the intestine than those in the IUGR-CON group (P < 0.05). In conclusion, DHA supplementation could improve intestinal morphology, regulate enterocyte proliferation and apoptosis, and alleviate intestinal inflammation through TLR4/NOD/NF-κB signaling pathway in weaned piglets with IUGR.  相似文献   
994.
Our previous studies demonstrated that dietary daidzein improves egg production in ducks during the late period of the laying cycle. The present study was aimed to investigate the effect of daidzein in laying hens, with more focus on eggshell quality. The expression of ER-alpha, GH-R, and IGF-IR mRNA in shell glands was determined to identify the target genes of daidzein action and to reveal the relationship between shell quality and profiles of gene expression in shell glands of laying hens. 1000 ISA hens, at 445 days of age, were allotted at random to two groups and given the basal diet with or without 10 mg of daidzein per kg diet for 9 weeks. Daidzein supplement significantly increased the egg laying rate and the feed conversion ratio. The eggshell thickness increased, while the percentage of cracked eggs decreased in daidzein-treated hens. Serum E2 and phosphate concentrations were not altered, but the level of serum Ca2+ and the tibia bone mineral density were significantly increased in the daidzein-treated group compared with their control counterparts. In parallel with the significant increase of oviduct weight, significant down-regulation of GH-R and IGF-IR mRNA and a trend of decrease in ERalpha mRNA expression in shell glands were observed in daidzein-treated hens. The results indicate that dietary daidzein improves egg laying performance and eggshell quality during the late (postpeak) laying stage of hens, which is associated with modulations in gene expression in the shell gland.  相似文献   
995.
This study analyzed 11 Chinese cultivars of marigold to determine their major phytochemical contents and antioxidant activities. Dried marigold flowers were extracted with ethanol, ethyl acetate, and n-hexane and the extracts were analyzed by high-performance liquid chromatography-mass spectrometry and chemical methods to determine their lutein esters, phenolic and flavonoid contents, and antioxidant activity, respectively. The different cultivars of marigold showed considerable variations in their lutein ester contents, ranging from 161.0 to 611.0 mg/100 g of flower (dry basis). The lutein esters in marigolds consisted predominantly of six all trans-diesters, but small amounts of cis isomers of the respective diesters were also present. The different cultivars of marigold also showed marked variations in total phenols and flavonoids, as well as antioxidant and radical-scavenging activities. Ethanol was confirmed to be the best solvent for extracting both phenols and flavonoids from marigold flowers, while n-hexane was the worst. The ethanolic extracts also exhibited the highest antioxidant and radical-scavenging activities. The cultivar Xinhong had the highest phenolic and flavonoid contents and radical-scavenging activity, as well as one of the highest lutein contents and antioxidant activities.  相似文献   
996.
AIMS: To document infant feeding methods in the first six months of life in Xinjiang Uygur Autonomous Region, People's Republic of China, 2003-2004. Some problems with breast-feeding in the area are explained. METHODS: A longitudinal study of infant feeding practices was undertaken. A total of 1219 mothers who delivered babies during 2003 and 2004 were interviewed in five hospitals or institutes, and after discharge were contacted in person or by telephone at approximately monthly intervals to obtain details of infant feeding practices. Multivariate logistic regression analysis was used to explore factors associated with breast-feeding initiation. RESULTS: 'Any breast-feeding' rates at discharge and at 0.5, 1.5, 2.5, 3.5, 4.5 and 6 months were 92.2, 91.3, 89.9, 88.8, 87.7, 86.0 and 73.0%, respectively. 'Exclusive breast-feeding' rates at discharge and at 0.5, 1.5, 2.5, 3.5, 4.5 and 6 months were 66.2, 47.6, 30.1, 25.8, 22.1, 13.0 and 6.2%, respectively. The main problem of breast-feeding in Xinjiang was the early introduction of formula or water. The average duration of 'exclusive breast-feeding' was 1.8 months (95% confidence interval (CI) 1.7-2.0), of 'full breast-feeding' 2.8 months (95% CI 2.7-2.9) and of 'any breast-feeding' 5.3 months (95% CI 5.2-5.4). CONCLUSIONS: Infant feeding methods in Xinjiang were documented in this study and the main problems with infant feeding in Xinjiang are discussed. Further studies are needed to identify factors associated with 'exclusive breast-feeding' and duration.  相似文献   
997.
Ginsenoside bioactive compounds, namely, compound K (C-K), compound Mx (C-Mx), and ginsenoside Mc (G-Mc), were the metabolites of ginsenosides Rb 1, Rb 2, Rb 3, and Rc by intestinal microflora of humans or rats, microorganisms, and enzymes, and C-K showed beneficial effects in vitro and in vivo as an antitumoral agent. The objective of this work was to explore an efficient procedure for biotransformation of these bioactive compounds. Thus, a filamentous fungus, Fusarium sacchari, was first obtained from the soil-cultivated ginseng, which was verified to possess a potent capacity of transformation of C-K, C-Mx, and G-Mc. The optimal biotransformation conditions of F. sacchari with C-K, C-Mx, and G-Mc were obtained as follows: transforming temperature, 30 degrees C; transforming time, 6 days; rotary speed, 160 rpm; pH of the medium, 5.5. HPLC analysis indicated that these three bioactive compounds were key metabolites and their structures were confirmed by (1)H and (13)C NMR analysis. Moreover, the in vitro antitumor activities of C-K, C-Mx, and G-Mc and the in vivo antitumor activities of the transformed product mainly containing these compounds were also evaluated. Among C-K, C-Mx, and G-Mc, C-K exhibited the most potent antitumor activities. The in vivo study showed that the transformed products by F. sacchari had much more antitumor activity than those of commonly used ginsenoside Rg3 and Paclitaxel.  相似文献   
998.
不同年限毛竹-灵芝复合系统土壤质量评价   总被引:1,自引:1,他引:0  
研究以不同年限(0 a、1 a和2 a)毛竹—灵芝复合系统为对象,对比分析灵芝不同种植年限的毛竹林土壤理化性质、酶活性等17个土壤质量指标的差异,并基于主成分分析对其土壤质量进行评价,旨在为毛竹林下种植灵芝提供参考。结果表明:随着灵芝种植年限的延长,毛竹林土壤含水率、孔隙度和通气度呈先升高后降低的变化趋势,而土壤容重呈先降低后升高的变化趋势;土壤pH值随种植年限的延长逐渐升高,有利于缓解土壤酸化;土壤有机质、全氮、全磷、全钾、速效养分含量和土壤酶活性均随种植年限的延长呈逐渐升高的变化趋势,且种植2 a显著高于0 a (P<0.05)。综合分析土壤理化性质以及酶活性等指标,毛竹林下种植灵芝后,其土壤质量指数均显著高于未种植的毛竹林地,且随种植年限的延长逐渐升高,说明灵芝种植有利于提高毛竹林地土壤质量。  相似文献   
999.
重点国有林区是我国最重要的森林生态功能区之一,在维护国家生态安全、应对气候变化、保障国家木材供给等方面发挥了重要作用,而森林旅游是重点国有林区转型发展的重要方向。文中基于重点国有林区森林旅游发展现状,对5个森工(林业)集团,以及100个国家级森林公园、湿地公园和自然保护区森林旅游发展情况进行了调查研究。结果表明,重点国有林区森林旅游发展的主要问题体现在自身投入能力弱、可游季短、林地审批困难、专业人才匮乏、资源同质性严重等多个方面;此外,区域发展水平不平衡不充分仍然突出,优势与短板长期共存,顶层设计和政策缺位。研究提出了推动重点国有林区森林旅游发展的政策建议,包括优化重点国有林区森林旅游空间布局、扩大森林旅游产品供给能力、拓展森林旅游客源市场、提升森林旅游人才培养能力、做好森林旅游发展政策支撑,以期为新时代重点国有林区森林旅游高质量发展提供参考。  相似文献   
1000.
划定生态保护红线是践行"两山"理念的时代任务与优先行动,推动生态产品价值实现则是新时代中国特色社会主义生态文明建设与"后脱贫时代"共同富裕协同推进的重要举措。文中首先在解释生态保护红线内涵的基础上,梳理东北国有林区生态保护红线政策的演进脉络,并以黑龙江省为例结合实际情况理清生态保护红线政策对林业产业发展的约束范围及程度;其次分别针对不同类型的生态产业,阐述生态保护红线对于生态产品价值实现的作用机理;最后从3个方面提出在生态保护红线政策下促进生态产品价值实现的建议:以森林资源为纽带,紧密联系森林碳汇建设与碳中和战略目标;建立物质类生态产品科技创新联盟,增强市场化支撑能力;打造东北国有林区森林生态综合体,促进文化服务类生态产品价值实现。研究可为东北国有林区未来促进生态产品价值实现提供参考,以促进林木资源保护和林业经济高质量发展。  相似文献   
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