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排序方式: 共有1280条查询结果,搜索用时 187 毫秒
1.
Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
2.
《Animal : an international journal of animal bioscience》2020,14(4):881-888
Lupine seeds have the potential to be an alternative to imported dietary proteins. In rabbits, it has been indicated that White lupine seed (WLS) is a suitable protein source. Other lupine species, for example, narrow-leaved lupine seed (NLS), have not yet been tested in rabbit diets. Two experiments were carried out to evaluate the effect of the dietary inclusion of NLS on growth performance, sanitary risk index (SRI), coefficients of total tract apparent digestibility (CTTAD) and nitrogen output in fattening rabbits. Narrow-leaved lupine was compared with WLS as a main protein source. For Experiment I, a total of 198 Hyplus rabbits (37 days of age) were allocated into two groups (99 rabbits per group), fed the WLS I diet (120 g/kg of WLS cv. Amiga) or the NLS I diet (150 g/kg of NLS cv. Probor), and used for performance and carcass trait evaluations. In addition, the CTTAD of the diets and the nitrogen output were determined in 10 Hyplus rabbits per treatment (37 days of age). For Experiment II, a total of 180 Hyplus rabbits (32 days of age) were allocated into two groups (90 rabbits per group), fed the WLS II diet (120 g/kg of WLS cv. Amiga) or the NLS II diet (130 g/kg of NLS cv. Primadona), and used for performance and carcass trait evaluations. In addition, the CTTAD of the diets was determined in 10 Hyplus rabbits per treatment (32 days of age). Regardless of the treatment, the dietary inclusion of NLS had a negative effect on growth of the rabbits. The nitrogen excretion and coefficients of nitrogen retention of rabbits were not affected by the treatments. In Experiment I, SRI (37 to 80 days of age) was higher in rabbits fed the NLS I diet than in those fed the WLS I diet (38.4% v. 23.2%, respectively; P = 0.031). Similarly, in Experiment II (32 to 74 days of age), SRI was higher in rabbits fed the NLS II diet than in rabbits fed the WLS II diet (37.8% v. 23.3%, respectively; P = 0.052). In conclusion, regardless of the variety, the dietary inclusion of NLS had no negative effect on the nitrogen output or dressing-out percentage of rabbits when compared to those of rabbits fed the WLS diets. With respect to the SRI and performance, however, NLS did not provide a satisfactory outcome. 相似文献
3.
S. Sharif P. Jacquiet F. Prevot C. Grisez I. Raymond‐Letron M. O. Semin A. Geffr C. Trumel M. Franc . Bouhsira E. Linard 《Medical and veterinary entomology》2019,33(2):247-255
Cattle besnoitiosis caused by Besnoitia besnoiti (Eucoccidiorida: Sarcocystidae) is a re‐emerging disease in Europe. Its mechanical transmission by biting flies has not been investigated since the 1960s. The aim of this study was to re‐examine the ability of Stomoxys calcitrans (Diptera: Muscidae) to transmit virulent B. besnoiti bradyzoites from chronically infected cows to susceptible rabbits. Three batches of 300 stable flies were allowed to take an interrupted bloodmeal on chronically infected cows, followed by an immediate bloodmeal on three rabbits (Group B). A control group of rabbits and a group exposed to the bites of non‐infected S. calcitrans were included in the study. Blood quantitative polymerase chain reaction (qPCR) analyses, and clinical, serological and haematological surveys were performed in the three groups over 152 days until the rabbits were killed. Quantitative PCR analyses and histological examinations were performed in 24 tissue samples per rabbit. Only one rabbit in Group B exhibited clinical signs of the acute phase of besnoitiosis (hyperthermia, weight loss, regenerative anaemia and transient positive qPCR in blood) and was seroconverted. Parasite DNA was detected in four tissue samples from this rabbit, but no cysts were observed on histological examination. These findings indicate that S. calcitrans may act as a mechanical vector of B. besnoiti more efficiently than was previously considered. 相似文献
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Virulence markers associated with Trueperella pyogenes infections in livestock and companion animals 下载免费PDF全文
8.
Microsatellite polymorphisms are invaluable for mapping vertebrate genomes. In order to estimate the occurrence of microsatellites in the rabbit genome and to assess their feasibility as markers in rabbit genetics, a survey on the presence of all types of mononucleotide, dinucleotide, trinucleotide and tetranucleotide repeats, with a length of about 20 bp or more, was conducted by searching the published rabbit DNA sequences in the EMBL nucleotide database (version 32). A total of 181 rabbit microsatellites could be extracted from the present database. The estimated frequency of microsatellites in the rabbit genome was one microsatellite for every 2–3 kb of DNA. Dinucleotide repeats constituted the prevailing class of microsatellites, followed by trinucleotide, mononucleotide and tetranucleotide repeats, respectively. The average length of the microsatellites, as found in the database, was 26, 23, 23 and 22 bp for mono-, di-, tri- and tetranucleotide repeats, respectively. The most common repeat motif was AG, followed by A, AC, AGG and CCG. This group comprised about 70% of all extracted rabbit microsatellites. About 61% of the microsatellites were found in non-coding regions of genes, whereas 15% resided in (protein) coding regions. A significant fraction of rabbit microsatellites (about 22%) was found within interspersed repetitive DNA sequences. 相似文献
9.
Cultured circular smooth muscle from the rabbit colon 总被引:1,自引:0,他引:1
H. W. Kao S. E. Finn A. M. Gown J. Lechago N. Lachant W. J. Snape Jr. 《In vitro cellular & developmental biology. Plant》1988,24(8):787-794
Summary Although cultured vascular smooth muscle cells have been extensively characterized and investigated, there are very few studies
of cultured intestinal smooth muscle cells. The aim of this study was to culture colonic smooth muscle (CSM) cells from the
rabbit colon. Freshly isolated CSM cells from the circular muscle layer of the distal colon were prepared by collagenase digestion.
In primary culture, CSM cells attached to the culture vessels by 48 to 72 h, proliferated by 3 to 7 d, and reached confluency
by 14 to 17 d with a “hill-and-valley” pattern. Spontaneous contractions were not observed at any time at 21° or 37° C. Confluent
primary cultures were greater than 95% CSM cells, as identified by intensely positive immunofluorescent staining to smooth
muscle actin-specific CGA7 and muscle-specific HHF-35 monoclonal antibodies. Transmission electron microscopy of freshly isolated
and proliferating CSM cells revealed ultrastructural features consistent with smooth muscle cells. We successfully cultured
CSM cells of the rabbit from freshly isolated cells and validated these CSM cells by electron microscopy and immunocytochemical
staining. These highly pure primary cultures may be used to investigate numerous aspects of CSM cell metabolism and physiology.
These studies were supported by the National Institutes of Health grant to the Inflammatory Bowel Disease Center (Bethesda,
MD) P30-AM-32200 and R01-DK-31147. Dr. Kao is the recipient of a Research Career Development Award from the National Foundation
for Ileitis and Colitis, Inc. A preliminary report of this work was presented at the American Motility Society Meeting, Houston,
TX, in October 1986, and appeared in abstract form inGastroenterology 91: 1057; 1986. 相似文献
10.
Floyd Green 《Biotechnic & histochemistry》2000,75(4):167-175
The synthetic dye industry is traced from its inception in England in 1856 to the European Continent and finally to the United States. The primitive state of this industry in America prior to World War I is described as is the desperate effort to develop the neglected technology once imports were difficult to obtain. Topics include biological stains, formation of the Biological Stain Commission (BSC), pioneers in the industry, dye shortages after World War II, formation of the Environmental Protection Agency (EPA), the decline of the domestic dye industry after the EPA was instituted, and the present state of the domestic dye industry. 相似文献