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11.
A trial was conducted to examine the effect of cinnamon essential oil supplementation on lamb growth performance and meat quality. Sixteen male lambs were randomly assigned to two groups. The first group served as control and was given a basal diet, and the second group was given the same diet supplemented with cinnamon oil (1 ml/kg of concentrated feed) for 35 days. Incorporation of cinnamon oil did not affect growth performance (P>0.05). Meat pH, colour, water-holding capacity, shear force, intramuscular fat and lipid oxidation values of longissimus thoracis muscle were not significantly influenced by cinnamon oil supplementation (P>0.05). The post-inoculation counts of Salmonella enteritidis and Listeria monocytogenes on raw meat during refrigerated storage for 6 days did not differ (P>0.05) between the two groups. The results show that cinnamon oil supplementation may not have the potential to improve lamb growth performance and meat quality characteristics.  相似文献   
12.
章燕    徐慧  夏宗伟  郭彦玲   《生态学杂志》2012,23(1):166-172
采用15N库稀释-原位培养法研究了硝化抑制剂DCD、DMPP对华北盐碱性褐土氮总矿化速率和硝化速率的影响.试验在山西省运城市种植玉米的盐碱性土壤上进行,设单施尿素、尿素+DCD、尿素+DMPP 3个处理.结果表明:施肥后2周,DCD、DMPP分别使氮总矿化速率和氮总硝化速率减少了25.5%、7.3%和60.3%、59.1%,DCD对氮总矿化速率的影响显著高于DMPP,两者对氮总硝化速率的影响无显著差异;而在施肥后7周,不同硝化抑制剂对氮总硝化速率的影响存在差异.施肥后2周,3个处理的土壤氮总矿化速率和硝化速率分别是施肥前的7.2~10.0倍和5.5~21.5倍;NH4+和NO3-消耗速率分别是施肥前的9.1~12.2倍和5.1~8.4倍,这是由氮肥对土壤的激发效应所致.硝化抑制剂使氮肥更多地以NH4+形式保持在土壤中,减少了NO3-的积累.土壤氮总矿化速率和总硝化速率受硝化抑制剂的抑制是N2O减排的主要原因.  相似文献   
13.
Molybdoenzymes are involved in a variety of essential pathways including nitrate assimilation, sulfur and/or purine metabolism and abscisic acid biosynthesis. Most organisms produce several such enzymes requiring a molybdopterin cofactor for catalytic function. Mutations that result in a lack of the molybdopterin cofactor display a pleiotropic loss of molybdoenzyme activities, and this phenotype has been used to identify genes involved in cofactor biosynthesis or utilization. Although several cofactor genes have been analyzed in prokaryotes, much less is known concerning eukaryotic molybdenum cofactor (MoCF) genes. This work is focused on the Drosophila MoCF gene cinnamon (cin) which encodes a multidomain protein, CIN, that shows significant similarity to three proteins encoded by separate prokaryotic MoCF genes. These domains are also present in the product of cnx1, an Arabidopsis MoCF gene, and in GEPHYRIN, a rat protein thought to organize the glycine receptor, GlyR, within the postsynaptic membrane. Since this apparent consolidation of separate prokaryotic genes into a single eukaryotic gene is a feature of other conserved metabolic pathways, we wished to determine whether the protein's function is also conserved. This report shows that the plant gene cnx1 can rescue both enzymatic and physiological defects of Drosophila carrying cin mutations, indicating that the two genes serve similar or identical functions. In addition, we have investigated the relationship between CINNAMON and GEPHYRIN, using immunohistochemical methods to localize the CIN protein in Drosophila embryos. Most of the CIN protein, like GEPHYRIN in the rat CNS, is localized to the cell borders and shows a tissue-specific pattern of expression. In a parallel study, antibody to GEPHYRIN revealed the same tissue-specific expression pattern in fly embryos. Both antibodies show altered staining patterns in cin mutants. Taken together, these results suggest that GEPHYRIN may also carry out a MoCF-related function. Received: 14 September 1998 / Accepted: 8 March 1999  相似文献   
14.
Nest survival of ducks is partially a function of the spatiotemporal characteristics of the site at which a bird chooses to nest. Nest survival is also a fundamental component of population growth in waterfowl but is relatively unstudied for cinnamon teal (Spatula cyanoptera). We investigated cinnamon teal nest survival in a managed wetland complex in southern Colorado, USA, and assessed nest site selection to determine whether nest site characteristics were adaptive. We monitored 85 nests in 2015–2017 on Monte Vista National Wildlife Refuge, Colorado and did not detect a difference in nest survival across years. Based on nest site selection data from 2017, cinnamon teal selected nest sites characterized by a lower proportion of forbs than available sites. The relationships between habitat characteristics and nest survival were variable. Microhabitat characteristics exhibited only weak effects on nest survival during the laying stage. Nest survival during incubation was negatively related to the proportion of forbs at the nest site and, to a lesser extent, the proportion of grasses. Nest site selection was predictive of future nest survival based on the percent of forbs and grasses around the nest site, suggesting teal select nest locations to benefit reproductive success. These results have the potential to guide local habitat management actions for breeding waterfowl. © 2020 The Wildlife Society.  相似文献   
15.
The IR3535 derivative (LJH158), in which the ethyl ester of IR3535 was converted to methyl ester, was synthesized and studied as a new mosquito repellent. The repellent efficacy of LJH158 was compared with that of DEET against Aedes albopictus, Culex pipiens pallens and Aedes togoi. Also, the aromatic repellent tests were conducted with mixtures of repellents and the essential oils of cinnamon, which were obtained by supercritical fluid extraction. In addition, the safety issues of LJH158 were monitored using single oral dose safety methods and eye irritation, and skin irritation tests. The results of repellent efficacy in both biting and aromatic tests and safety tests demonstrate that LJH158 has high potential to be used as a new repellent or in combination with other repellents.  相似文献   
16.
施锌对石灰性褐土上小白菜光合作用及保护酶活性的影响   总被引:5,自引:0,他引:5  
通过田间试验的方法,采用30(低锌)、75(中锌)和120kg/hm2ZnSO4(高锌)3个施锌水平,研究施锌对山西省石灰性褐土上小白菜叶片叶绿素含量、净光合速率、硝酸还原酶(NR)活性、抗氧化酶活性及丙二醛(MDA)含量的影响.结果表明:随着施锌量的提高,小白菜叶片各叶绿素组分含量、总叶绿素含量、净光合速率和NR活性均呈先升后降的变化趋势,并均以中锌处理最大,且中、高锌处理显著高于对照(不施锌);小白菜叶片过氧化物酶(POD)和过氧化氢酶(CAT)活性也呈先升后降的趋势,而超氧化物歧化酶(SOD)活性持续增加,CAT、POD和SOD活性分别在低锌、中锌和高锌处理时达到最大值,所有施锌处理的3种保护酶活性均显著高于缺锌对照;各处理小白菜叶片MDA含量随着施锌量增大而逐渐降低,且所有施锌处理均显著低于缺锌对照.研究发现,施锌能有效增强石灰性褐土上小白菜叶片光合能力和氮同化能力,显著提高其抗氧化酶系活性,并以75kg/hm2ZnSO4效果最佳.  相似文献   
17.
河北主要土壤中Cd、Pb形态与油菜有效性的关系   总被引:55,自引:1,他引:55  
刘霞  刘树庆  唐兆宏 《生态学报》2002,22(10):1688-1694
当今土壤重金属污染日趋严重而表征土壤污染程度 的指标不够完善、相关性亦较差。为此,采用网室盆栽试验,研究了河北平原主要土壤类型潮土和潮褐土上Cd、Pb的化学形态特征及其与油菜植株干物重、油菜吸收重金属含量的关系。结果表明Cd对油菜的毒害作用大于Pb。总量及各形态Cd、Pb含量与油菜可食部分干物重呈负相关,对油菜干物重影响最大的是交换态Cd、Pb。而对油菜吸收Cd、Pb贡献最大的形态是碳酸盐结合态和铁锰氧化物结合态。深入研究重金属形成与植物有效性间的关系,可为进一步揭示重金属的生物有效性,为更准确评价土壤重金属污染程度提供理论依据,具有重要的理论意义和实际应用价值。  相似文献   
18.
长江中下游低丘不同开发模式的土壤改良效果   总被引:23,自引:0,他引:23  
对长江中下游4个不同试点综合治理和开发模式的调查表明,综合治理和开发后,低丘植被覆盖率增加,水土流失和土壤侵蚀量降低,土壤容重下降,土壤含水率平均提高18.14%,土壤有机质、N、P、K含量均有提高.  相似文献   
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20.
Stored cut lettuce gradually turns brown on the cut section after several days of storage, because cutting induces phenylalanine ammonia-lyase (PAL) activity, the biosynthesis of polyphenol is promoted, and the polyphenols are oxidized by polyphenol oxidase. In this study, we screened for inhibitors of PAL derived from fermented broths of microbes and from foods and found that a cinnamon extract definitely inhibited PLA of cut lettuce. An active component was isolated by chromatographic procedures and was identified as trans-cinnamaldehyde. Browning of cut lettuce immersed in a solution containing trans-cinnamaldehyde was definitely repressed.  相似文献   
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