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81.
通过多年的园林苗圃试验与生产实践 ,对一些厦门地区常见的绿化树种的采种期、种子处理、种子贮藏、育苗方法及苗木抚育等种苗培育技术进行了较为全面的探讨 相似文献
82.
介绍园林有机废物变栽培基质的原因、过程,产品应用实例,表明园林有机废物变栽培基质是节约型园林绿化发展的新途径,具有较好的社会效益和生态效益。 相似文献
83.
Adenosine protects Sprague Dawley rats from high‐fat diet and repeated acute restraint stress‐induced intestinal inflammation and altered expression of nutrient transporters
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C. Y. Lee 《Journal of animal physiology and animal nutrition》2015,99(2):317-325
This study investigated the effect of repeated acute restraint stress and high‐fat diet (HFD) on intestinal expression of nutrient transporters, concomitant to intestinal inflammation. The ability of adenosine to reverse any change was examined. Six‐week‐old male Sprague Dawley rats were divided into eight groups: control or non‐stressed (C), rats exposed to restraint stress for 6 h per day for 14 days (S), control rats fed with HFD (CHF) and restraint‐stressed rats fed with HFD (SHF); four additional groups received the same treatments and were also given 50 mg/l adenosine dissolved in drinking water. Fasting blood glucose, plasma insulin, adiponectin and corticosterone were measured. Intestinal expression of SLC5A1, SLC2A2, NPC1L1 and TNF‐α was analysed. Histological evaluation was conducted to observe for morphological and anatomical changes in the intestinal tissues. Results showed that HFD feeding increased glucose and insulin levels, and repeated acute restraint stress raised the corticosterone level by 22%. Exposure to both stress and HFD caused a further increase in corticosterone to 41%, while decreasing plasma adiponectin level. Restraint stress altered intestinal expression of SLC5A1, SLC2A2 and NPC1L1. These changes were enhanced in SHF rats. Adenosine was found to alleviate HFD‐induced increase in glucose and insulin levels, suppress elevation of corticosterone in S rats and improve the altered nutrient transporters expression profiles. It also prevented upregulation of TNF‐α in the intestine of SHF rats. In summary, a combination of stress and HFD exaggerated stress‐ and HFD‐induced pathophysiological changes in the intestine, and biochemical parameters related to obesity. Adenosine attenuated the elevation of corticosterone and altered expression of SLC5A1, NPC1L1 and TNF‐α. 相似文献
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85.
文章从广州地区城市绿化工程投标工作的实践经验出发,简要总结回顾了广州地区城市绿化工程招投标历程,分析了目前招投标市场竞争中存在问题的主要表现形式及原因,提出了规范市场机制、加强职能部门监管、相关参与者依法依规、行业维护自律和企业内部强化管理等相应的解决途径,并提出了实施企业备案市场准入制度、严格审查资格条件、强调企业综合实力和加强招投标对工程造价的控制作用等建议。 相似文献
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87.
以百合科宿根花卉大花萱草、"金娃娃"萱草、"甜心"玉簪、东北玉簪为研究材料,研究其在Cd质量浓度为40mg/kg处理下,随着植物体内镉的积累,不同时期4种花卉生理生长的响应,并根据各项指标的测定结果对4种花卉的抗镉胁迫能力进行综合评定。结果表明,镉胁迫下,植株受害情况不仅受时间主效应的影响,还受时间×树种、时间×树种×质量浓度交互效应的影响。经方差分析和多重对比,并用隶属函数法进行综合评定,得出4种花卉的抗镉胁迫能力强弱顺序依次为"甜心"玉簪、"金娃娃"萱草、大花萱草和东北玉簪。 相似文献
88.
以九单48和松玉656两个玉米品种为材料,对幼苗期不同时期各叶片表皮细胞和气孔的量化指标进行较系统的研究。结果表明,在试验范围内,各叶片上下表皮细胞和气孔的长与宽均表现为随着叶片的生长而逐渐增大;各叶片在初次取样时其上下表皮细胞和气孔长与宽的数值是相近的;上表皮细胞短而宽,下表皮细胞长而窄;上表皮气孔长小于下表皮的气孔长、上表皮气孔宽大于下表皮的气孔宽;各叶片上下表皮细胞和气孔的面积均表现为随叶面积增加而逐渐增大;上表皮细胞面积小于下表皮细胞面积,而上表皮气孔面积大于下表皮气孔面积;上下表皮细胞和气孔的密度均随叶面积增加而逐渐减小。 相似文献
89.
Tiziana La Rosa Simone Mirto Antonio Mazzola Teresa Luciana Maugeri 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):153-167
We studied the impact of organic loads due to the biodeposition of a fish farm in a non-impacted coastal area of the Tyrrhenian Sea (Western Mediterranean). Sediment chemistry and benthic microbial community were investigated from July 1997 to February 1998 on monthly basis at two stations: one was located under the fish farm, while the second was about 1 km away, and served as a reference site. The presence of the cage induced rapid changes in the benthic conditions: the sediments were rapidly (after 6 weeks) reduced. A significant accumulation of biopolymeric carbon was observed beneath the cage both 2 weeks after the initial cage deployment, on non-impacted sediments, and 5–7 months after, and appeared to be related to the fish farm production cycle. The density of microbial communities beneath the fish farm increased only during the first month of farming activity (July) and partially 7 months after cage disposal (i.e. in January), when there was a significant sediment organic enrichment. Additional evidence of rapid impact of the fish farm on the benthic bacterial communities is provided by the increase in the numbers of autofluorescent microbial cells. The photosynthetic eukaryotic cells displayed a highly reduced contribution to total autofluorescent microbial density, indicating that their decrease is related with biopolymeric carbon accumulation, and probably was due also to “shadow effect” induced by suspended material, coming from the fish farm, on the environment below. We propose here, to apply the ratio of culturable heterotrophic bacteria to microbial direct counts (CFU/MDC) to detect fish farm impact. In cage sediments, organic enrichment and the consequent modification of the characteristics of the benthic environment, determined an increase in aerobic heterotrophic bacteria and vibrio density indicating that they are efficient colonizers of organic-rich sediments. Densities of Escherichia coli and Enterococci were not significantly higher than in the reference site, and are likely of terrestrial origin. Thus they cannot be used as specific indicators of fish farm impact. 相似文献
90.
Mark D. Needham Jerry J. Vaske Doug Whittaker Maureen P. Donnelly 《Human Dimensions of Wildlife》2014,19(3):288-299
Recreationists who encounter more people than their normative tolerance for seeing others usually feel more crowded than those encountering fewer than their norm. This research note extends this observation–norm–evaluation relationship (e.g., encounter–norm–crowding) to other evaluations and indicators. Data were from a survey of anglers on the Gulkana National Wild River in Alaska (n = 288). Respondents who encountered more people than their norm felt more crowded than those encountering fewer than their norm. When impacts from other social indicators (e.g., camping within sight or sound of other groups, fishing area competition) exceeded user norms, crowding was higher and satisfaction with overall trip quality was lower than for those experiencing less than their norms. When impacts from resource indicators (e.g., litter, impacted campsites) exceeded norms, satisfaction with both environmental quality and trip quality were lower than for those experiencing less than their norms. The encounter–norm– crowding generalization, therefore, extended to other indicators and evaluations. 相似文献