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21.
以云南稻种耐冷性资源昆明小白谷及弱耐冷性的日本品种十和田配制的杂交F2代为材料,采用159个RFLP及SSR分子标记构建的连锁图和STATISTIC等分析软件,以单株结实率作为耐冷性评价指标.分析结果显示单株结实率与单株特定颖花结实率之间的相关系数(r)为0.8364;与耐冷性(以单株结实率为指标)相关的分子标记有43个,分布在8条染色体  相似文献   
22.
The spring bloom of phytoplankton is a well-established, regular, seasonal event in the western subarctic Pacific and is considered one of the most important conditions of massive production of pelagic fishes. A series of 12 cruises was conducted from 1990 to 1992 to examine the timing and magnitude of the spring phytoplankton bloom in the Oyashio region, the western subarctic Pacific off Hokkaido, Japan. An interannual variability in the bloom events was also analysed. On the basis of hydrographical characteristics, the study area was divided into three water masses: the Oyashio Water Mass, the Mixed Water Mass, and the Coastal Water Mass. Spring blooms were observed first in April in the Oyashio and the Coastal Water Masses, and continued to May in 1991 and 1992. However, no bloom was recorded in the Mixed Water Mass. High nutrient supply into the surface mixed layer during winter is likely to be one of the factors supporting an intense spring bloom in the Oyashio Water Mass. A significant positive relationship between log-transformed surface chlorophyll a concentration and maximum density gradient (MDG) within the euphotic layer was obtained in April, indicating the importance of vertical stability of the water column in the initiation of spring blooms in the Oyashio and the Coastal Water Masses. The spring blooms in 1991 were much more extensive and lasted longer than in 1990. It is suggested that meteorological conditions and abundance of grazers were responsible for this interannual difference.  相似文献   
23.
碎石填方边坡是山区公路常见的一种坡面类型。表层为以碎石为主的土石混合体,土壤含量极少甚至没有,立地条件恶劣,导致坡面植被恢复非常困难。针对这一难题,以北京市门头沟区百花山旅游公路11 km处的45°碎石填方边坡为研究对象,采用"客土+保育块苗移栽"技术,在坡面上重建了乔灌草植物群落。施工4 a后,坡面草本植物群落的总覆盖度约为50%,平均高度约为40 cm;坡面木本植物生长状况良好,主根粗壮、根系发达且已深入碎石缝隙之中,其中山桃保育块苗的成活率为78%,高度为82 cm,地径为7.9 mm。实验结果表明,该方法可以在比较陡峭的碎石覆盖边坡上有效地构建乔灌草植物群落。  相似文献   
24.
The purpose of this mini-review is to describe the recent approaches for revealing the function of the central nervous system in farm animals. The sensory organs are the first sites to gain environmental information. The behavior of the animals is outputted as a result of changes in the integrated neuronal systems, and is largely influenced by the external environment. Therefore, it is necessary to know how farm animals catch and recognize environmental changes. To understand the mechanisms of sensing and behavioral output, approaches for analyzing the brain function are required. Neuroscientific approaches are able to give cues for resolving abnormal behaviors such as stereotypy, and may lead to the improved housing and management of farm animals.  相似文献   
25.
The chemoattractant activity of a new chemotactic factor, 'Gasserokine' produced by Lactobacillus gasseri JCM1131T, has been proposed as a novel immunological function of probiotic lactic acid bacteria. The focus of the present study was to understand the mechanism of the chemotaxis induced by Gasserokine, using activation of an adhesion molecule, Mac-1 (CD11b/CD18) on macrophages. The macrophage chemotaxis to Gasserokine was abolished by preincubation of macrophages with the anti-Mac-1 mAb. Gasserokine induced rapid serine phosphorylation of CD18 molecules within 1 min of stimulation, but the effect was short-lived. Substantial tyrosine phosphorylation was observed in CD18-associated protein of macrophages stimulated by Gasserokine. The tyrosine phosphorylation was confirmed in macrophages stimulated with Gasserokine and also serine/threonine phosphorylation was detected on CD18 molecules by laser microscopy using a double immunostaining method. These results suggest that selective activation of intracellular signaling cascades, such as the mitogen-activated protein kinase pathway, are related to the macrophage chemotaxis induced by Gasserokine.  相似文献   
26.
The number of Sustainable Green Ecosystem Council (SGEC) certified forests in Japan has increased in recent years. As such it is important to understand forest management certification within the context of corrective action requests (CARs) to assess sustainable forest management. This study analyzes trends in CARs issued through evaluations of SGEC certified forests in Japan as a function of certification body, forest zone, size of forest holdings, and forest ownership type. This study examined 86 certified forests in Japan using data from summary evaluations published by SGEC certification bodies in 2014. Forests in the northern zone tend to have more CARs assigned, as did larger forests and communally owned forests. For managers interested in maintaining sustainable forests, the findings suggest that they should focus on improving the following indicators: “training and instruction, such as the safety for forestry workers” (indicator 5.3), “to evaluate forest practices against the original plan and to assess their impacts, with proper monitoring” (indicator 7.1), “explicit and management policy of the important elements in the conservation of biological diversity”(indicator 2.2) and “protection of threatened species” (indicator 2.3). The results from this study suggest that certification bodies have different priorities in their certification assessments, as indicated by the varying number and types of CARs assigned. However, the findings also indicate that the factors affecting the assessment results may not be only the certification body issuing the assessments but also the forest zone, forest ownership type, and size of forest holdings.  相似文献   
27.
28.
The histology and immunohistochemistry of pleomorphic and conventional epithelioid mesotheliomas were examined. The former was detected in two young calves aged 2 and 4 months and was characterized by pleomorphic and atypical cells with decreased expression of cytokeratin 7 (CK7). In contrast, the latter was found in a 31-month-old heifer, consisting of tumor cells uniform in size and shape with CK7 expression in nearly all cells. Production of collagen by tumor cells was demonstrated in both histological types, and was considered to be characteristic of bovine epithelioid mesothelioma. Pleomorphic mesothelioma is far more pleomorphic and mitotically active than conventional mesothelioma, and its normal counterpart may be immature mesothelial cells with high proliferation potential, which exist in fetal life and early calfhood.  相似文献   
29.
The spatial distribution and seasonal variability of epipelagic chaetognaths along the Kurile Islands and off south-east Hokkaido, in the western subarctic Pacific Ocean. were investigated during the period from May 1990 to October 1992. Sagitta elegans was the dominant species among the epipelagic chaetognaths in the study area. Juvenile S. elegans were distributed mainly along the path of the mixed water which was determined by the acceleration potential anomaly (APA) at the iso-pycnal density surface of 26.6 σθ. The location of the path of The mixed water meandered around cyclonic and anticyclonic eddies. Catches of S. elegans were made at temperatures ranging from 4.5 to 22.2C. The juvenile distribution, however, was mostly restricted to between 1 and 4C of the potential temperature determined at the isopycnal density surface of 26.6 σθ. Variability in the juvenile abundance within the path of the mixed water could be caused by predation rather than by food limitation because microzooplankton, which are known to he prey for juveniles, were abundant enough to meet the food requirements of juveniles in the study area. Adults occurred in spring (April-May) and young individuals (juvenile and stage 1) were abundant in summer (June-July), when a strong thermocline developed. The main spawning period appears to be during April-May, with a possible second spawning period in the autumn.  相似文献   
30.
An experiment was conducted to determine the effects of inclusion levels of potato pulp silage in concentrate (0, 15, 30 or 45%; on a dry matter basis) and roughage sources (rice straw or wheat straw) on finishing performance and carcass quality of cull beef cows. Sixteen Japanese Black (Wagyu) mature cull cows (490 ± 31 kg of BW) were used in this experiment. Increasing the levels of potato pulp silage in concentrate and roughage sources did not significantly affect feed intake in cows. In addition, the final body weight, daily gain and feed : gain ratio were not influenced by the inclusion levels of potato pulp silage in concentrate and the type of roughage. Increasing the inclusion levels of potato pulp silage in concentrate would probably decrease the marbling score. The L* values of the longissimus muscle (LM) tended to respond quadratically ( P  = 0.078) as the inclusion levels of potato pulp silage in concentrate increased, and was lowest for cows fed the concentrate which included 30% potato pulp silage. The a* and b* values of the LM and fat color were not affected by the inclusion levels of potato pulp silage in concentrate. No effects of roughage sources on finishing performance were observed.  相似文献   
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