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61.
M Dehnhard T Hildebrandt M Rohleder G Strauss H H Meyer F G?ritz 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(5-6):161-165
Populations of African (Loxodonta Africana) and Asian Elephants (Elephas maximus) in zoos and safari parks are at risk due to their low reproductive success. To extend the limited knowledge of their reproductive physiology, the development of easy and practical methods for the analysis of the relevant reproductive hormones is essential to support e.g. assisted reproduction. For the measurement of 5 alpha-pregnane-3,20-dione (DHP), the predominant ovarian gestagen in both species, an enzyme-immunoassay (EIA) based on commercial reagents was applied. Advantages of this EIA are the small volume of plasma needed for evaluation (5 microliters) and the possibility of direct processing without an extraction stage. The lower limit of detection was 0.16 ng/ml, the mean recovery was 101% and the mean coefficients of variation were 7.3% (intra-assay) and 9.9% (inter-assay). In Asian elephants, DHP levels reached 15 ng/ml during the luteal phase and up to 21 ng/ml during pregnancy. Estrous cycle lengths based on the lowest DHP concentrations varied from 12 to 20 weeks (mean 15.4 +/- 2.3). In two Asian elephant cows a calf was still-borne. Thereafter, the animals reassumed ovarian activity after approximately 8 and 13 weeks, respectively. In one animal estradiol implants for hormonal contraception caused a down regulation of the ovarian function as demonstrated by an irregular pattern of DHP secretion over a period of 48 weeks. We propose the direct DHP-EIA as a suitable method for reproductive monitoring in elephants, as it can be easily established in laboratories. 相似文献
62.
Effect of shrimp head protein hydrolysates on the state of water and denaturation of fish myofibrils during dehydration 总被引:1,自引:0,他引:1
Yaowalux?Ruttanapornvareesakul Misako?Ikeda Kenji?HaraEmail author Kazufumi?Osako Orawan?Kongpun Yukinori?Nozaki 《Fisheries Science》2005,71(1):220-228
ABSTRACT: To utilize fisheries waste products as food materials with functional properties, shrimp head protein hydrolysates (SHPH) from three species of shrimp, that is, Northern pink shrimp ( Pandalus eous ), Endeavour shrimp ( Metapenaeus endeavouri ) and Black tiger shrimp ( Penaeus monodon ), were produced by enzymatic hydrolysis using endopeptidase derived from Bacillus subtilis and exopeptidase derived from Aspergillus oryzae at a level of 0.1% (w/w). SHPH were rich in protein (90–91%) and amino acids (71–84%) but little fat (0.01–0.02%). The average molecular weight of SHPH was 300–1400. The effect of 5% SHPH (dry basis) addition on the state of water and denaturation of lizard fish myofibrils (Mf) during the dehydration process was evaluated by the desorption isotherm and the Ca-ATPase activity, and compared with the effect of sodium glutamate (Na-Glu). SHPH decreased the water activity and the Ca-ATPase inactivation, and increased monolayer sorbed water and multilayer sorbed water of Mf, although these effects of SHPH were smaller than those of Na-Glu. These findings suggest that the SHPH suppressed dehydration-induced denaturation of myofibrillar protein by stabilizing the hydrated water surrounding myofibrils. 相似文献
63.
以台儿庄区为研究区域,通过搜集2005、2009、2014年3个年份的土地利用状况数据为基础,研究2005~2014年该区域各土地利用类型面积、分布及程度在时间和区域空间的变化,以期对区域土地利用方向和资源管理提供理论和技术支持。结果表明,台儿庄区近十年来农用地总量减少4.23 km~2,建设用地增加6.03 km~2;各乡镇街道中运河街道变化较大,结构变化指数为30.45,土地利用程度变化率高于全区整体水平。 相似文献
64.
本研究以波尔山羊为实验动物,旨在观察钼镉联合胁迫对山羊肾脏细胞凋亡相关基因表达的影响。选用63头健康波尔山羊随机分成7组,每组3个重复,选用七钼酸铵([(NH4)6Mo7O24·4H2O])作为实验钼源,氯化镉(Cd Cl2)作为实验镉源,按每kg山羊体质量添加钼、镉对照组(Mo 0 mg/kg+Cd 0 mg/kg),低镉低钼组(Mo 15mg/kg+Cd 0.5 mg/kg),低镉中钼组(Mo 30 mg/kg+Cd 0.5 mg/kg),低镉高钼组(Mo 45 mg/kg+Cd 0.5 mg/kg),高镉低钼组(Mo 15 mg/kg+Cd 1.0 mg/kg),高镉中钼组(Mo 30 mg/kg+Cd 1.0 mg/kg),高镉高钼组(Mo 45 mg/kg+Cd1.0 mg/kg),实验期50 d。并于当天、第25、50天每组各剖杀3头山羊取肾组织进行相关实验,观察不同剂量钼、镉对山羊肾脏细胞凋亡相关基因表达等的影响。结果显示,与对照组相比,在实验第25、50天时,实验组山羊肾脏bcl-2 mRNA表达量下降(P0.01),bax mRNA、caspase-3 mRNA和cytc mRNA表达量上升(P0.05或P0.01);山羊钼镉联合胁迫导致肾线粒体抗氧化功能降低、自由基含量升高,导致细胞促凋亡基因表达量上升,抗凋亡基因的表达量下降,提示钼镉联合胁迫对山羊肾脏有明显损伤。 相似文献
65.
Georgios?Kountios Athanasios?RagkosEmail author Thomas?Bournaris Georgios?Papadavid Anastasios?Michailidis 《Precision Agriculture》2018,19(3):537-554
Precision agriculture (PA) constitutes a dynamic production method which is gaining attention in several parts of the world. Its environmental and economic sustainability has been examined in terms of its ability to reduce the adverse effects of agrochemical use—by regulating their application to the levels needed at the land parcel level—and of its contribution to higher incomes and profitability. At the social level, PA has been linked to collective action although little insight is available regarding the role of various actors and education. This study tackles PA through an assessment of the attitudes of farmers towards the elements of its sustainability and of their educational needs. The analysis of survey data of a sample of young farmers in Greece showed that the majority of respondents were not familiar with PA. Significant differences were found between the attitudes of knowledgeable and non-knowledgeable farmers, the former demonstrating better acknowledgement of the environmental, economic and social sustainability of PA. Important educational needs were also detected, with group and individual methods being the most preferred ones for education and information campaigns. The results of the analysis could be of use for the design of Common Agricultural Policy Pillar II measures for the promotion of PA targeting to specific audiences and actors. 相似文献
66.
Ioannis?GravalosEmail author Anastasios?Georgiadis Dimitrios?Kateris Theodoros?Gialamas Evagelos?Bompolas Zisis?Tsiropoulos Avgoustinos?Avgoustis Panagiotis?Xyradakis 《Precision Agriculture》2017,18(1):19-36
This research is a study on the relationship of irrigation water treatments and soil moisture distribution uniformity (DU). Soil moisture distribution was based on long-term data sets that were collected using a novel electromagnetic sensor-based platform moving inside sub-surface horizontal access-tubes. The research was conducted under controlled laboratory conditions in a soil tank. The irrigation treatments regarding two case studies under dry and wet soil conditions (from permanent wilting point to field capacity) were conducted for a period of 115 and 110 days respectively. In dry soil conditions, the irrigation water treatments strongly affect the DU of soil moisture that can be achieved constantly using non-uniform irrigation treatments. In contrast, the DU of soil moisture in wet soil conditions was maintained at a high percentage and was slightly affected by irrigation treatments. However, obtaining accurate soil moisture information at a large scale over a long period can be used to improve water use efficiency. 相似文献
67.
68.
A series of monoazo disperse dyes based on 2-amino-4-phenylthiazole was prepared using variousN,N-dialkylaniline derivatives as the coupling component. The dyes were characterized by IR spectral studies, visible absorption
spectroscopy and elemental analysis. The dyeing performance of these dyes was assessed on cellulose triacetate and nylon fibers.
These dyes were found to give a wide range of colour shades varying from bright red to royal blue with very good depth, brightness
and levelness on fibers. The dyed fibers showed good to very good light fastness and very good to excellent fastness to washing,
perspiration, rubbing and sublimation. The dyebath exhaustion and fixation on the fibers were found to be very good. 相似文献
69.
Henrik Harms Barbora Orlikova Seungwon Ji Damun Nesaei-Mosaferan Gabriele M. K?nig Marc Diederich 《Marine drugs》2015,13(8):4949-4966
The Ascomycota Dichotomomyces cejpii was isolated from the marine sponge Callyspongia cf. C. flammea. A new gliotoxin derivative, 6-acetylmonodethiogliotoxin (1) was obtained from fungal extracts. Compounds 2 and 3, methylthio-gliotoxin derivatives were formerly only known as semi-synthetic compounds and are here described as natural products. Additionally the polyketide heveadride (4) was isolated. Compounds 1, 2 and 4 dose-dependently down-regulated TNFα-induced NF-κB activity in human chronic myeloid leukemia cells with IC50s of 38.5 ± 1.2 µM, 65.7 ± 2.0 µM and 82.7 ± 11.3 µM, respectively. The molecular mechanism was studied with the most potent compound 1 and results indicate downstream inhibitory effects targeting binding of NF-κB to DNA. Compound 1 thus demonstrates potential of epimonothiodiketopiperazine-derived compounds for the development of NF-κB inhibitors. 相似文献
70.
Claire Bouvard Isabelle Galy-Fauroux Fran?oise Grelac Wassila Carpentier Anna Lokajczyk Sophie Gandrille Sylvia Colliec-Jouault Anne-Marie Fischer Dominique Helley 《Marine drugs》2015,13(12):7446-7462
Low-molecular-weight fucoidan (LMWF) is a sulfated polysaccharide extracted from brown seaweed that presents antithrombotic and pro-angiogenic properties. However, its mechanism of action is not well-characterized. Here, we studied the effects of LMWF on cell signaling and whole genome expression in human umbilical vein endothelial cells and endothelial colony forming cells. We observed that LMWF and vascular endothelial growth factor had synergistic effects on cell signaling, and more interestingly that LMWF by itself, in the absence of other growth factors, was able to trigger the activation of the PI3K/AKT pathway, which plays a crucial role in angiogenesis and vasculogenesis. We also observed that the effects of LMWF on cell migration were PI3K/AKT-dependent and that LMWF modulated the expression of genes involved at different levels of the neovessel formation process, such as cell migration and cytoskeleton organization, cell mobilization and homing. This provides a better understanding of LMWF’s mechanism of action and confirms that it could be an interesting therapeutic approach for vascular repair. 相似文献