首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   15篇
  免费   0篇
林业   2篇
  2篇
综合类   1篇
水产渔业   2篇
畜牧兽医   3篇
园艺   1篇
植物保护   4篇
  2020年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   1篇
  2013年   3篇
  2011年   1篇
  2008年   3篇
  2006年   1篇
  2002年   2篇
排序方式: 共有15条查询结果,搜索用时 15 毫秒
1.
The control of aquaculture in the Republic of Ireland falls under a number of different legislative codes and, consequently, responsibility for the regulation of the industry is divided between a number of ministers and state agencies. The principal responsibility lies with the Minister for the Marine and Natural Resources. The 1997 Fisheries Act was framed to replace an outdated regulatory system with one which would enjoy the confidence of a rapidly expanding industry and of all other relevant interests, in particular by establishing an independent authority for the determination of aquaculture license appeals. Powers in relation to the authorisation and control of medicines are shared between the Minister for Agriculture and the Minister for Health, while local authorities are responsible for planning permission and discharge licenses in respect of land-based facilities.  相似文献   
2.
To evaluate the contribution of rock fragments to the soil's total carbon content, the soil of 26 sites, ranging from the Canadian Arctic to the Jordan desert, was analysed for the content of organic C and total N in both fine earth and skeleton fractions. The soils, uncultivated and cultivated, are derived from 11 parent materials: sandstone, mica-schist, granite, gneiss, basaltic pyroclastites, trachyte, dolomite, beach deposits, clay schist, marl and serpentinite. For each soil horizon the contents of fine earth and skeleton were determined by volume. Both fractions were analysed for bulk density, total and organic C and total N. Our results indicate that rock fragments contain amounts of C and N that depend on the nature of the parent material and on its resistance to the weathering processes. The C and N of both fine earth and skeleton were used to calculate the contents of these elements for three depths. At each depth, the skeleton contributes C and N to the soil depending on its abundance. We conclude that the contribution of the rock fragments to the soil C and N cannot be predicted from the soil taxa, but can from the parent material. Calculations that exclude C and N of the skeleton could lead to errors in the estimates of these two elements in soils.  相似文献   
3.
The Middle Stone Age (MSA) is associated with early behavioral innovations, expansions of modern humans within and out of Africa, and occasional population bottlenecks. Several innovations in the MSA are seen in an archaeological sequence in the rock shelter Sibudu (South Africa). At ~77,000 years ago, people constructed plant bedding from sedges and other monocotyledons topped with aromatic leaves containing insecticidal and larvicidal chemicals. Beginning at ~73,000 years ago, bedding was burned, presumably for site maintenance. By ~58,000 years ago, bedding construction, burning, and other forms of site use and maintenance intensified, suggesting that settlement strategies changed. Behavioral differences between ~77,000 and 58,000 years ago may coincide with population fluctuations in Africa.  相似文献   
4.
Salmonella typhi (S. typhi) is an important pathogen which causes typhoid fever. The cytokines released from the macrophages, playing a role in the host defense against Salmonella infection, are crucial in the defense against the infection. IFN-γ provides a protection against Salmonella infection by developing macrophage activation in different mechanisms. This study was designed to investigate the effect of the recombinant IFN-γ (rIFN-γ) on the cytokines secreted from S. typhi stimulated macrophages. Macrophage isolation was done in the heparinized blood samples obtained from healthy people, and following the priming with rIFN-γ for 72 h the cells were stimulated by S. typhi and then the cytokine levels in culture supernatants were determined by enzyme-linked immunosorbent assay. It was observed that rIFN-γ reversely increased the levels of IL-1, IL-2 the levels of which were decreased by S. typhi and that it increased TNF-α levels while suppressing the levels of antiinflammatory cytokines such as IL-10 and TGF-β the levels of which were increased by S. typhi. Consequently, rIFN was observed to increase protective Th1 response by affecting the secretion of cytokine during S. typhi infection and it was considered to be a good target especially to prevent and treat invasive Salmonella infections.  相似文献   
5.
Sea trout, Salmo trutta L., populations in the Slupia River basin have been affected by mass stocking with smolts and fry. This work is focused on a small‐scale differentiation in sea trout populations from one basin with a strong emphasis on the relationship between wild and hatchery origin fish. A total of 216 sea trout were genotyped at 10 microsatellite loci. Global FST obtained by amova was low at 0.0165. Pairwise FST were significant for all tests except wild and stocked adults. The highest pairwise difference was found between the hatchery sample and Kwacza (FST = 0.038). Analysis of the genetic structure revealed micro‐geographical differentiation with four subpopulations. The quality of the artificial spawning was found not to be adequate with a high risk of adverse effects to the whole population. All future stocking actions in the basin should consider the existing population structures.  相似文献   
6.
7.
Forty-two kiwifruit orchards from Rize and Samsun provinces (Black Sea region, Turkey) exhibiting symptoms of root rot disease were examined between 2009 and 2010. Twenty-four fungal isolates recovered from affected roots were included in this study. Morphological characteristics of all isolates were recorded on potato dextrose agar, malt extract agar and Spezieller Nährstoffarmer agar. The effect of temperature on radial colony growth was also evaluated at 5, 10, 15, 20, 25, 30, and 35 °C. Histone H3 gene (HIS) was amplified with primers CYLH3F and CYLH3R and the amplified fragments were sequenced. The HIS phylogeny grouped all the isolates into six well-supported clades which were in agreement with phenotypical characteristics. Isolates were identified as “Cylindrocarponpauciseptatum, Cylindrocladiella parva, Ilyonectria liriodendri, I. torresensis, I. robusta and I. europaea, I. liriodendri being the most frequent species. All of them are reported for the first time on kiwifruit in Turkey, with the exception of I. liriodendri. Pathogenicity tests with selected isolates showed that 10 out of 11 isolates tested were able to induce typical root rot disease symptoms, affecting plant development and leading to the death of some plants. This study shows the high diversity of root rot pathogens found in kiwifruit trees in the Black Sea region of Turkey, being the first step towards a better understanding and management of the disease in local conditions.  相似文献   
8.
The attribution of economic value to landscape resources is fraught with technical and methodological difficulties. Little is mandated in UK planning policy explaining how economic value should be established. As a result landscape resources have been undervalued, underfunded and marginalised in favour of larger grey infrastructure development. The UK NEA however outlined for the first time a national scale economic evaluation of environmental resources. The Valuing Attractive Landscapes in the Urban Economy (VALUE) Interreg IVB project examined this issue by establishing a toolkit of economic evaluation methodologies for green investments across North-West Europe. Focussing on the returns that investments in green infrastructure can deliver to cities and city-regions, the VALUE project identified economic values that can be used to influence future policy-making. This paper presents an analysis of VALUE street tree investments in Manchester, UK. Using a contingent valuation survey preferences for green investments and associated willingness to pay (WTP) for them were generated. Analysis suggests that willingness to pay is directly related to the size and greenness of the proposed investment and participant perceptions of added value. 75% of respondents were WTP for investments in green infrastructure. Analysis indicates increased WTP and a marked preference for larger and physically greener investments. Payment values ranged from £1.46 to 2.33, a 59.5% variance, between the preferred investment option and the status quo. The paper concludes that although green investments vary in size and function, respondents consider the specific and wider value of green infrastructure resources when asked how much they willing to pay to fund and maintain such investments.  相似文献   
9.
1. The aim of the present study is to describe, immunohistochemically, the expression and cell type localisation of growth factor receptors and some of their ligands in the oropharyngeal organs of the Chukar partridge.

2. The tissue samples from 10 healthy adult partridges were dissected under ether anaesthesia and then embedded in paraffin following routine histological procedures. The immunoreaction for receptors and ligands of the epidermal growth factor receptor (EGFR)/ligand system was localised in the cell membrane, nucleus and cytoplasm of the luminal and glandular epithelial cells, stromal and striated muscle cells, and vascular endothelial and smooth muscle cells.

3. Variations were observed in the avian oropharyngeal organs. The immunostaining for the erbB1/HER1 (human epidermal growth factor receptor 1) and the EGF (epidermal growth factor) and AREG (Amphiregulin) ligands in the luminal epithelial cells was higher than in the glandular epithelial, stromal and striated muscle cells. However, the immunostaining for erbB3/HER3 (human epidermal growth factor receptor 3) and erbB4/HER4 (human epidermal growth factor receptor 4) were similar in the luminal epithelium, stromal and striated muscle cells.

4. Growth factor receptors and some of their ligands were localised in different cell types in the oropharyngeal organs. We suggest that erbB/HERs (human epidermal growth factor receptors) and their ligands play an important role in proliferation, differentiation, growth, survival and migration of the cells.  相似文献   

10.
In this study, we aimed to observe the localization and expression of peptide hormones—leptin, ghrelin and obestatin—in the sheep tongue by immunohistochemistry. For that purpose, tongues of ten adult sheep were used. Leptin expression of moderate intensity was observed in the basal and parabasal epithelial cells of the luminal epithelium, and leptin was strongly expressed in the taste buds of the circumvallate and fungiform papillae and in von Ebner's glands. Ghrelin was primarily expressed in some of the skeletal muscle cells and the smooth muscle cells of the middle layer of blood vessels. A strong expression was observed in the epithelial cells lining the base of the groove surrounding the circumvallate papillae. Obestatin expression was particularly strong in the epithelial cells of the salivary ducts. It was also stronger in the von Ebner's glands than in the seromucous glands. Leptin, ghrelin and obestatin were shown to be produced at varying levels in different cell types, including epithelial, stromal and skeletal muscle cells, as well as in ganglion neurons, neural plexuses and blood vessels in the sheep tongue. Cellular localization and expression of these peptide hormones have not been investigated in many species including sheep.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号