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排序方式: 共有1035条查询结果,搜索用时 15 毫秒
121.
The paper is concerned with simulating the macroeconomic adjustment processes arising in a small open economy experiencing a temporary period of oil production. In a recent paper, Harvie conducted a similar exercise for an economy in which the spending effect arising from such oil production dominated the resource movement effect. That paper concluded that the wage adjustment processes operative were important in influencing the macroeconomic adjustment process arising. Specifically, that paper concluded that wage indexation was preferable during the period of oil production, but that de-indexation was preferable in the post oil production period. Although, in the present paper, the principles underlying the simulated model are the same as in Harvie, the emphasis here is placed on the resource movement consequences arising from temporary oil production. The major conclusion identified is that wages policy is still important in influencing the macroeconomic adjustment processes identified. However, a difference arises not in regard to the profile of that adjustment but rather in its magnitude. The paper emphasizes, in particular, developments in non-oil output, consumer prices, and the stock of domestically held foreign assets. The simulation results suggest that, where the resource movement effect dominates, it would be preferable to de-index wages during the period of oil production and index wages in the post oil production period. Hence wages policy should be regarded as an important component of a government's policy response arising from a period of temporary oil production, irrespective of whether the resource movement or spending effect dominates. However, what that policy response should be would depend on the relative importance of either effect. 相似文献
122.
123.
The serum tocopherol levels were determined on 923 workers (18–62 years of age) from the textile, chemical and metallurgical industries. Tocopherol levels varied between 0,20 and 1,86 mg per 100 ml serum, the mean value being 0,77 ± 0,01 mg per 100 ml, but in 148 subjects (16%) concentrations under 0,5 mg per 100 ml were found. For women the average was significantly (p < 0,05) lower than that for men (0,75 ± 0,02 compared to 0,79 ± 0,01) and the prevalence of levels below 0,5 mg per 100 ml greater (18,4% compared to 12,6%). Independent of sex the serum tocopherol level increased with age (from 0,59 ± 0,02 under 26 years, to 0,87 ± 0,05 mg per 100 ml for the group over 55 years, p < 0,001). By grouping the persons according to the tocopherol levels (A = up to 0,5 mg per 100 ml; B = 0,51–1,0 and C = over 1,0 mg per 100 ml) and by calculating for each group the average values of the daily fat intake (supplied especially by sunflower oil) a relationship was found between the two series of values, but overall this did not reach statistical significance. 相似文献
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126.
Arcamone N Lucini C Borzacchiello G Castaldo L Gargiulo G De Girolamo P 《Microscopy research and technique》2005,66(1):17-24
By means of immunochemistry and immunohistochemistry, we investigated in the kidney of freshwater and marine teleostean species for the presence and localization of three neurotrophins: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin (NT)-3. In both species studied, NGF-like and NT-3-like immunoreactivity were present in the kidney with different distribution patterns, while BDNF-like immunoreactivity was never detected. In goldfish, NGF-like and NT-3-like immunoreactivity were identified extensively in cells along part of the arterial branches adjacent to the afferent arterioles. In scorpion fish, NGF-like and NT-3-like immunoreactive cells were observed both on afferent arterioles and on adjacent secondary branches derived from renal arteries. No immunoreactivity was detected in other renal structures. A staining pattern of immunoreactivity similar to that obtained for NGF and NT-3 was detected utilizing S100 antibody as a juxtaglomerular (JG) cell marker. Double immunolabellings NGF/S100 and NT-3/S100 evidenced the coexistence of neurotrophin-like proteins and S100-like protein in the same immunoreactive cells, thus identifying them as juxtaglomerular cells. Western blot analysis revealed the presence of molecules immunoreactive to NGF and NT-3, whose molecular weights were very similar to those of the corresponding mammalian neurotrophins. These findings extend the presence and distribution of NGF-like and NT-3-like IR in the kidney to teleost species, suggesting a probable participation of these proteins in the renal functions of freshwater and marine teleosts. 相似文献
127.
When assessing the potential of a contaminated site for bioremediation, it is desirable to know how much of the contaminant(s) is available for microbial degradation, thus allowing the likelihood of successful bioremediation to be predicted. The aims of this study were to investigate the degradation of PAHs in two soils by a catabolic inoculum and indigenous soil microflora and link this to the cyclodextrin extractable fraction in the presence of transformer oil (0.05, 0.01, or 0.005%). This study showed very little difference between indigenous and inoculum-derived degradation for phenanthrene in laboratory-aged soil, and strong relationships were also observed between both of the microbial degradative conditions and the amount of phenanthrene extracted by cyclodextrin. Furthermore, the indigenous degradation of PAHs in a field-contaminated soil showed significant linear correlations with the cyclodextrin extractable fraction, with gradients approximating to 1. There are several novel facets to this study. First, in aged, contaminated soils, indigenous microflora gave an equally sensitive determination of degradative availability as that measured by the catabolic inoculum. Second, this is the first time intrinsic biodegradation of PAHs has been predicted by the cyclodextrin extraction in laboratory-spiked and field-contaminated soils. The cyclodextrin extraction technique represents a powerful tool for predicting the extent of intrinsic and augmented microbial degradation and will be useful in the assessment of contaminated land prior to bioremediation. 相似文献
128.
A. Magnani E. Busi R. Barbucci 《Journal of materials science. Materials in medicine》1994,5(12):839-843
The adsorption of two proteins from human plasma (human serum albumin (HSA) and human fibrinogen (HFG) onto six different polymeric surfaces (two of which are heparinized), has been studied byin situ ATR/FTIR spectroscopy. The different surface characteristics are reflected by different interfacial behaviours of the two proteins, but while both proteins unfold upon adsorption on all the different non-heparinized materials, they maintain the native conformation once adsorbed on the heparinized surfaces. These findings emphasize the effectiveness of surface heparinization. 相似文献
129.
Nadia Magnenat-Thalmann Alain Choquette Daniel Thalmann 《Microprocessors and Microsystems》1983,7(3):107-110
A powerful graphical PASCAL extension has transferred from a large computer to a microcomputer. The graphical extension, called M1RA-2D, allows the user to program computer graphics applications in a modern, structured and efficient language. The problems encountered were mainly due to the limits of a microcomputer-based system and to the size of the project. Problems involved memory space, documentation, low-power peripherals, PASCAL restrictions and hardware robustness and quality. Finally, M1RA-2D is compared with two other graphics software packages implemented on microcomputers: Applegraphics and an implementation of a 2D, level 2 Core System. 相似文献
130.
Nadia Waegeneers Michel Hoenig Ludwig De Temmerman 《The Science of the total environment》2009,407(15):4397-4429
The purpose of this study was to evaluate the levels of arsenic, cadmium, lead, copper and zinc in home-produced eggs, soils and kitchen waste samples of private chicken owners in Belgium, and to determine spatiotemporal differences in trace element contents in eggs. Eggs were sampled in all provinces of Belgium in autumn 2006 and spring 2007. A total number of 59 private chicken owners participated in the study. Trace elements were determined by inductively coupled plasma-mass spectrometry except for mercury, which was determined by atomic absorption of mercury vapour. The mean fresh weight concentrations in eggs in autumn and spring respectively were < 8.0 and < 8.0 µg/kg for arsenic, 0.5 and < 0.5 µg/kg for cadmium, 116 and 74 µg/kg for lead, 0.43 and 0.52 mg/kg for copper, 20.3 and 19.2 mg/kg for zinc, and 3.15 and 4.44 µg/kg for mercury. Analysis of variance determined significant differences in some trace element concentrations in eggs among seasons and regions in Belgium. Average concentrations of arsenic, cadmium and mercury corresponded well with values measured in other countries, while copper and zinc concentrations were within the same order of magnitude as in other countries. Average lead concentrations were high compared to concentrations in eggs from other countries and correlated well with lead concentrations in soil, indicating that the soil is an important source. Other sources of trace elements in eggs might be home-grown vegetables and forage (grass and herbs), and indirectly, air pollution. 相似文献