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131.
Bottom-sediment cores were used to investigate the occurrence of 44 metals and trace elements, and 15 organochlorine compounds in Tuttle Creek Lake, a reservoir with an agricultural basin in northeast Kansas, U.S.A. On the basis of U.S. Environmental Protection Agency sediment-quality guidelines, concentrations of Ag, As, Cr, Cu, Ni, and Zn frequently or typically exceeded the threshold-effects levels for toxic biological effects. Organochlorine compounds either were not detected or were detected at concentrations generally below the threshold-effects levels. Statistically significant positive depositional trends were determined for several elements. However, because the vertical profiles of element concentrations typically indicated a bimodal distribution and much of the variability could be attributable to analytical variance, the statistical trends may not represent actual trends. DDE concentrations reflected the history of DDT use. Substantial increases in grain corn and soybean production, irrigated land, and hog production in the basin have not had a discernible effect on sediment quality in the reservoir. Future research focused on small impoundments throughout the basin may enhance understanding of the effects of human activity on sediment quality within the Tuttle Creek Lake system and elsewhere. 相似文献
132.
山丹黄参的分布及微量元素含量研究 总被引:4,自引:0,他引:4
山丹黄参是伞形科迷果芹属的迷果芹(Sphallerocarpus gracilis)经测定,该植物含有大量人体必需的各种微量元素,其中P,Mg、K、Cu、Cr、Co含量比党参(Codonopsis pilosula)和当归(Angelica sinensis)还高,Zn,Mn的水平也不低,是一种营养丰富的绿色食品,具有广泛的应用与开发前景。 相似文献
133.
Dag Brune 《Biological trace element research》1987,13(1):319-331
Nuclear corrosion technique has been developed for the assay of various heavy metals released through corrosion and abrasion
into electrolytes from various biomaterials like amalgams, chromium— cobalt and gold alloys, steel, and titanium. Application
of the technique in measurement of selective release rates under static or dynamic conditions, i.e., during cyclic loading,
is discussed. The elements chromium, cobalt, copper, gold, iron, mercury, molybdenum, silver, titanium, and zinc have been
quantitatively assessed. In vivo corrosion measurements are further included. By combining the present nuclear tracer technique
with ESCA technique, knowledge about reaction mechanisms occurring at the interface solid/liquid is obtained. Exposure of
humans to various heavy metals from biomaterials, e.g., dental materials, can be estimated using the NCM technique. The technique
also has a potential for selective release measurements of several nuclides possessing suitable radioanalytical properties
from other types of alloys immersed in various liquid environments. 相似文献
134.
《Archives of animal nutrition》2013,67(4):324-337
ABSTRACTThis experiment was conducted to evaluate the effects of different sources and levels of trace elements on growth performance, carcass composition and mineral excretion levels of broilers. In a completely randomised experimental design, 900 one-day-old male Ross-308 broilers were assigned to 5 treatments, with 6 replicates of 30 birds each. The control group (CITE) was fed with a basal diet containing regular inclusion levels of inorganic trace elements. Treatment groups were supplied with reduced levels (30% and 50% of the regular level) of inorganic (ITE) or organic trace elements (OTE), respectively. Groups 50% ITE, 30% OTE and 50% OTE diets had equivalent average daily gain (ADG), average daily feed intake (ADFI), feed to gain ratio (F/G ratio) and mortality rate compared with group CITE in any phase. However, compared with group CITE chicks in group 30% ITE have lower ADG and ADFI and higher F/G ratio. The carcass yields were not affected by dietary treatments. Compared with group CITE, in groups 30% ITE, 50% ITE, 30% OTE and 50% OTE the shear force values of the breast muscle were only 71.8%, 83.4%, 63.5% and 59.4% (p < 0.05), respectively. Birds received diets containing reduced levels of trace elements had diminished excretions of Mn and Zn throughout the entire period (p < 0.01). In conclusion, the reduced supplementation of trace elements had no or slightly negative impact on growth performance, carcass yield and meat quality, but decreased faecal mineral excretion. Moreover, the trace element supply as OTE played a limited role on performance and excretion and was only partly beneficial for animal performance in case the trace element supply was reduced to 30%. 相似文献
135.
To assess the potential health risks associated with selected trace elements due to consumption of bivalves, a screening-level risk assessment was conducted through consideration of internationally accepted dietary guidelines and the calculation of hazard quotients. Seventeen edible bivalve species were collected from a local market in Dalian City, China. The ranges obtained for the trace elements analyzed in mg/kg dry weight were as follows: Cu (1.8–133), Zn (56–693), Mn (5.7–150), Se (0.2–3.8), Ni (0.56–7.67), Cd (0.04–10.3), Cr (0.48–2.23), Pb (0.01–1.63), Hg (0.07–0.35), and As (0.22–4.00). The estimated daily intake (EDI) of bivalves was 15.0–255.1 times lower than the RfD guidelines for all the trace elements studied. Further, the calculated hazard quotients (HQs) of the trace elements analyzed were well less than 1. Therefore, there were no potential human health risks to Dalian City consumers of marine bivalves. 相似文献
136.
Mustafa Durmuş Ali Rıza Kosker Yeşim Ozogul Mehmet Aydin Yılmaz UÇar Deniz Ayas 《人类与生态风险评估》2018,24(3):731-742
The effects of seasonal and sexual differences on the levels of macro, trace element, and toxic metal levels in Mullus barbatus were investigated using the ICP-MS. The quantity relationships of macro elements were found as K>P>Na>Ca>Mg for male, P>K>Na>Ca>Mg in female; the quantity relationships of trace elements were determined as Fe>Zn>Mn>Mo>Se>Cu>Ni>Co in male, Fe>Zn>Mn>Se>Cu>Ni>Mo>Co in female; and the quantity relationship of toxic elements were found as As>Pb>Cd in both male and female. Macro, trace, and toxic metal levels showed no significant differences (p > .05) in terms of sexuality, but demonstrated seasonal differences (p > .05). Overall, the highest level of macro elements was determined in the autumn, while the high level of trace elements was measured in the winter. The As, Cd, and Pb levels in the muscle tissue of red mullet fish were higher than acceptable limits. However, when the Estimated Daily Intake (EDI) and Estimated Weekly Intake (EWI) of both toxic metals are considered, they appear to be below acceptable limits. As a result, it was determined that the red mullet had been contaminated with toxic metals (Cd and Pb) but their levels according to EDI and EWI were below the limit. 相似文献
137.
Rheumatoid arthritis (RA) is a chronic autoimmune systemic inflammatory disease that is characterized by synovial inflammation and bone erosion. We have investigated the mechanism(s) by which essential trace metals may initiate and propagate inflammatory phenotypes in synovial fibroblasts. We used HIG-82, rabbit fibroblast-like synovial cells (FLS), as a model system for potentially initiating RA through oxidative stress. We used potassium peroxychromate (PPC, Cr+5), ferrous chloride (FeCl2, Fe+2), and cuprous chloride (CuCl, Cu+) trace metal agents as exogenous pro-oxidants. Intracellular ROS was quantified by fluorescence microscopy and confirmed by flow cytometry (FC). Protein expression levels were measured by western blot and FC, while ELISA was used to quantify the levels of cytokines. Trace metal agents in different valence states acted as exogenous pro-oxidants that generate reactive oxygen species (ROS), which signal through TLR4 stimulation. ROS/TLR4- coupled activation resulted in the release of HMGB1, TNF-α, IL-1β, and IL-10 in conjunction with upregulation of myeloid-related protein (MRP8/14) inflammatory markers that may contribute to the RA pathophysiology. Our results indicate that oxidant-induced TLR4 activation can release HMGB1 in combination with other inflammatory cytokines to mediate pro-inflammatory actions that contribute to RA pathogenesis. The pathway by which inflammatory and tissue erosive changes may occur in this model system possibly underlies the need for functioning anti-HMGB1-releasing agents and antioxidants that possess both dual trace metal chelating and oxidant scavenging properties in a directed combinatorial therapy for RA. 相似文献
138.
J. Velasco-V⟹quez M. Armay-de-la-Rosa E. González-Reimers O. Hernández-Torres 《Biological trace element research》1997,59(1-3):207-213
In order to deepen our knowledge of the dietary habits of the prehispanic inhabitants of El Hierro, we have determined bone
strontium (Sr), manganese (Mn), magnesium (Mg), copper (Cu), zinc (Zn), and calcium (Ca) in 52 human tibiae (23 belonging
to male and 20 to female individuals) buried in a single burial cave; in 21 modern individuals who served as controls; and
in 11 bones of herbivores found at archeological sites of the Canary Islands. Results suggest that females consumed a more
vegetarian diet, although site-corrected Sr/Ca ratio of both males and females speaks for a mixed-diet consumption. 相似文献
139.
The concentrations of 19 trace element in hair samples from 1273 residents of Harbin (China), Medan (Indonesia), and Tokushima
(Japan) were measured by inductively coupled plasma emission spectrometry. The mean concentrations of Ba, Ca, and Se were
significantly higher in the Harbin hair samples when compared to those from Medan, but Al, B, Cu, Fe, Mn, Na, Pb, Ti, Zn,
and K were significantly higher in Medan than in Harbin hair samples. The differences in the mean concentrations of As, Cr,
Mg, P, Sn, and Sr between the Medan and Harbin lots were not significant. In the Tokushima hair samples, Na and K were significantly
higher, but As, B, Ba, Ca, Cr, Mg, Mn, Pb, Sn, Sr, and Se were significantly lower than in the Harbin hair samples. The differences
in the mean concentrations of Al, Cu, Fe, P, Ti, and Zn between Harbin and Tokushima were not significant. In the Medan hair
samples, Al, As, B, Ba, Ca, Cr, Cu, Fe, Mg, Mn, Pb, Sn, Sr, Ti, and Zn were significantly higher, but P and Se were significantly
lower than in Tokushima hair samples. Differences in mean concentrations of Na and K between Tokushima and Medan were not
significant. 相似文献
140.
The cytotoxic interaction of inorganic trace elements with EDTA and cisplatin in sensitive and resistant human ovarian cancer cells 总被引:1,自引:0,他引:1
Robert H. Maier Susan M. Purser Daniel L. Nicholson Walter J. Pories 《In vitro cellular & developmental biology. Animal》1997,33(3):218-221
Summary Cisplatin (CDDP)-sensitive and -resistant human ovarian cells were studied in vitro with the objective of enhancing CDDP cytotoxicity by the addition of a metal and the chelate ethylenediaminetetraacetic acid
(EDTA), to the CDDP. Chelateable elements, such as bismuth, calcium, cadmium, copper, iron, magnesium, selenium, vanadium,
and zinc, when added to CDDP and in the presence of EDTA increased the cytotoxicity of the CDDP as compared to CDDP treatment
alone. 相似文献