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本文介绍了开发城市地下空间的必然趋势及前景,阐明开发利用城市地下空间,对节省城市用地、节约能源、改善城市交通、减轻城市污染等都有着重要作用。  相似文献   
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In extensive cattle production systems, the composition of grazing areas may significantly influence productivity. In dual-purpose cattle production systems in the lowland tropics, pasture lands with trees, so-called silvopastoral areas, are considered as being important, particularly to facilitate the management of crossbred European native cattle. The aim of the study was to quantify the effects of silvopastoral areas on production at dual-purpose cattle farms in the semi-humid lowlands of central Nicaragua. The relationships between seasonal milk production and herd data, and the proportions of land use types were examined for 74 farms by stepwise regression analysis.  相似文献   
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Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet.  相似文献   
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为研究雷帕霉素靶标激酶TOR在牡丹开花衰老过程中的生理作用,以牡丹(Paeonia suffruticosa Andr.)‘洛阳红’切花为试材,用0.01 μmol • L-1雷帕霉素预处理2 h后瓶插,并测定瓶插寿命、能量物质含量、糖分含量、乙烯释放速率、呼吸速率、MDA含量以及PsTOR、PsSnRK1和PsHXK1表达量变化。结果表明:雷帕霉素预处理可延长该牡丹切花的瓶插最佳观赏期和增大花朵的最大花径;另外,雷帕霉素预处理还可提高花瓣可溶性糖含量和能荷积累,降低呼吸耗能和MDA含量,并下调瓶插初期PsSnRK1和PsHXK1的表达水平,上调瓶插后期PsTOR和PsSnRK1的表达水平。说明雷帕霉素可通过TOR途径调控能量感知,延缓牡丹切花的开放和衰老进程,进而提高瓶插品质。  相似文献   
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Cryoprotectant is the crucial factor in the cryopreservation process. In general, there are two types of cryoprotectant, permeating and non‐permeating cryoprotectants. Dimethyl sulfoxide (DMSO) and egg yolk are common permeating and non‐permeating cryoprotectants respectively. Hence, the objective of the present study was to determine the best proportion of DMSO and egg yolk for the cryopreservation of Rasbora tawarensis sperm. A completely randomized experimental design was used in this study which involves two types of cryoprotectant and their combination at different concentrations, namely 5% DMSO, 5% egg yolk, 5% DMSO + 5% egg yolk and 2.5% DMSO + 2.5% egg yolk. Every treatment was conducted in three replicates. Combination of 5% DMSO + 5% egg yolk gave the best results cryoprotectant treatment had significant effects on sperm motility, fertilization and hatching rate of the R. tawarensis eggs (p < .05). It is concluded that the best proportion of cryoprotectants for sperm cryopreservation in this species is 5% DMSO + 5% egg yolk.  相似文献   
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There is no report of diversity, biological properties and bioactive compounds of sponge-associated fungi from Indonesia’s mangrove ecosystem to date. This study was designed to isolate sponge-associated fungi from a mangrove ecosystem in Mangkang, to screen the antimicrobial and extracellular enzyme properties of the isolates, characterize the biologically promising isolates using molecular approaches, and profile the secondary metabolites using phytochemical and thin-layer chromatography (TLC) analyses. An unidentified sponge that lived in association with mangrove roots was collected from Mangkang. Total of eight associated fungi were isolated from the sponge. Among all isolates, only two fungi SPMKF 1 and SPMKF 6 produced extracellular amylase, another two fungi SPMKF 4 and 5 showed antibacterial activity against MRSA, and only one fungus SPMKF 8 was able to produce extracellular amylase and show antimicrobial activity against ESBL E. coli, Salmonella enterica ser. Typhi strain MDR and C. albicans, while SPMKF 2, SPMKF 3 and SPMKF 9 did not show any biological properties. The result of genetic characterization proved that SPMKF 1 was Cladosporium tenuissimum, SPMKF 4 was Eutypella sp., SPMKF 5 was Lasiodiplodia theobromae, SPMKF 6 was Fusarium keratoplasticum and SPMKF 8 was F. solani. Furthermore, an amylase gene was detected in fungi SPMKF 1, 6 and 8 while among the BGC, only NRPS genes were detected in SPMKF 4, 5 and 8. Interestingly, several same metabolites indicating the same retention factor (Rf) values in TLC were detected in the fungal crude extracts by TLC.  相似文献   
8.
The pharmacokinetic profile, tolerability and efficacy of benzene‐poly‐carboxylic acids complex with cis‐diammineplatinum (II) dichloride (BP‐C1) were studied in dogs with mammary cancer. A three‐level response surface pathway designed trial was performed on seven dogs. At each level BP‐C1 was administered subcutaneously daily for 7 days followed by a 7‐day rest period in a dose escalating manner. Adverse events according to VCOG‐CTCAE, performance status and tumour progression were recorded. The pharmacokinetic profile followed a two‐compartment model with rapid absorption, short distribution, and a slow elimination phase. The overall elimination half‐life was 125 h. The maximum tolerated dose of BP‐C1 was estimated to be above 0.46 mg kg?1. A significant reduction in VCOG‐CTCAE toxicity which correlated negatively with increasing dose was found. The dogs' general performance status remained unchanged. No decrease in total tumour burden was found, although temporary tumour reduction was seen in some target tumours.  相似文献   
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