首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Transport characteristics of certain inorganic elements such as copper, magnesium, selenium and iron have been studied in maternal-fetal direction in normal pregnancies, using in vitro perfusion of isolated placental lobules. Copper, selenium, magnesium and iron salts corresponding to twice physiological concentrations were injected as a 100 l bolus, into the maternal arterial perfusate. Serial perfusate samples were collected from venous outflows for a study period of 5 min. Concentrations of various inorganic elements and their transport kinetics were determined. Transport fractions of copper, selenium, magnesium and iron averaged 0.14, 0.19, 0.06 and 0.23% of maternal load respectively. The pharmacokinetic parameters such as area under the curve, clearance, elimination constant, and time for maximum response showed some significant differences between the various elements. We speculate that copper and selenium share the same transport pathway along a concentration gradient in maternal-fetal direction, while for iron and magnesium, active transport plays a predominant role for element transfer across the human placental membrane.  相似文献   

2.
Preeclampsia is an important cause of maternal and perinatal mortality worldwide. The etiology of this relatively common medical complication of pregnancy, however, remains unknown. We studied the relationship between maternal leukocyte selenium, zinc, and copper concentrations and the risk of preeclampsia in a large hospital-based case-control study. One hundred seventy-one women with proteinuric pregnancy-induced hypertension (with or without seizures) comprised the case group. Controls were 184 normotensive pregnant women. Leukocytes were separated from blood samples collected during the patients’ postpartum labor and delivery admission. Leukocyte concentrations for the three cations were measured by inductively coupled plasma-mass spectrometry (ICP-MS). Concentrations for each cation were reported as micrograms per gram of total protein. Women with preeclampsia had significantly higher median leukocyte selenium concentrations than normotensive controls (3.23 vs 2.80 μg/g total protein, p<0.0001). Median leukocyte zinc concentrations were 31% higher in preeclamptics as compared with controls (179.15 vs 136.44 μg/g total protein, p<0.0001). Although median leukocyte copper concentrations were slightly higher for cases than controls, this difference did not reach statistical significance (17.72 vs 17.00 μg/g total protein, p=0.468). There was evidence of a linear increase in risk of preeclampsia with increasing concentrations of selenium and zinc. The relative risk for preeclampsia was 3.38 (adjusted odds ratio [OR]=3.38, 95% confidence interval [CI]=1.53–7.54) among women in the highest quartile of the control selenium distribution compared with women in the lowest quartile. The corresponding relative risk and 95% CI for preeclampsia was 5.30 (2.45–11.44) for women in the highest quartile of the control zinc distribution compared with women in the lowest quartile. There was no clear pattern of a linear trend in risk with increasing concentration of leukocyte copper concentrations (adjusted for linear trend in risk =0.299). Our results are consistent with some previous reports. Prospective studies are needed to determine whether observed alterations in selenium and zinc concentrations precede preeclampsia or whether the differences may be attributed to preeclampsia-related alterations in maternal and fetal-placental trace metal metabolism.  相似文献   

3.
Samples of wild growing ectomycorrhizal and terrestrial saprobic macrofungi (mushrooms) were collected from unpolluted areas and analyzed for their iron, cobalt, zinc and selenium content. Trace elements were determined using long-term instrumental neutron activation analysis. In total, 217 samples, including 87 species of ectomycorrhizal fungi and 43 species of terrestrial saprobes, were examined. Distribution of trace element contents in ectomycorrhizal and saprobic macrofungi was investigated; results are thoroughly compared with previously published data. Doubtful literature data and ability of macrofungi to accumulate/concentrate investigated elements are discussed. Hygrophoropsis aurantiaca was found to concentrate Fe and Russula atropurpurea was confirmed as an effective Zn-accumulating species. Distribution of Se in ectomycorrhizal species was obviously different from that in saprobic species; selenium contents were higher in saprobic species (mostly above 2 ppm).  相似文献   

4.
Appropriate nutrition is a key component of burn treatment and should be regarded as an integral part of the therapeutic process in burn patients. A nutritional intervention plan should not only allow for adequate quantities of energy and protein but also carefully consider the supply of macro- and micronutrients. As a result of the severe inflammatory response, oxidative stress, and hypermetabolic state, accompanied by often extensive exudation in burn patients, there is a considerable loss of macro- and micronutrients, including essential trace elements. This leads to certain complications, involving e.g. more frequent infections and impaired wound healing. Our current body of knowledge is still insufficient, and the studies carried out to date focus for the most part on the imbalances in trace elements, such as copper (Cu), selenium (Se), and zinc (Zn). Nevertheless, there are many other trace elements involved in immune functions, regulating gene expression or antioxidant defense, and many of those have not been properly investigated in a clinical setting. Due to the insufficient amount of unambiguous literature data and relatively few, often dated, studies carried out with small patient groups, further evaluation of macro- and microelements in burn patients seems indispensable, e.g. to bring up to date local nutritional protocols.  相似文献   

5.
ProjectRecurrent aphthous stomatitis (RAS) is a common oral mucosal disorder characterized by recurrent, painful oral aphthae, and oxidative stress presumably contributes to its pathogenesis. The aim of this study is to scrutinize the relationship between oxidative stress and serum trace elements (copper, Cu; zinc, Zn; selenium, Se), and to evaluate the ratios of Cu/Zn and Cu/Se in this disorder.ProcedurePatients with RAS (n = 33) and age- and sex-matched healthy control subjects (n = 30) were enrolled in this study. Malondialdehyde (MDA) concentrations in plasma and the activities of superoxide dismutase (SOD1; CuZnSOD), glutathione peroxidase (GPx) and catalase (CAT) in erythrocyte were determined as spectrophotometric. Also, the levels of Se, Zn and Cu in serum were determined on flame and furnace atomic absorption spectrophotometer using Zeeman background correction.Results and conclusionsOxidative stress was confirmed by the significant elevation in plasma MDA, and by the significant decrease in CAT, SOD1, and GPx (p < 0.05). When compared to controls, Zn and Se levels were significantly lower in patients, whereas Cu levels was higher in RAS patients than those in controls (p < 0.05). In addition, the correlation results of this study were firstly shown that there were significant and positive correlations between Se–CAT, Se–GPx, and Cu–MDA parameters, but negative correlations between Se–Cu, Se–MDA, Cu–CAT, Cu–SOD1 and Cu–GPx parameters in RAS patients. Furthermore, the ratios of Cu/Zn and Cu/Se were significantly higher in the patients than the control subjects (p < 0.05). Our results indicated that lipid peroxidation associated with the imbalance of the trace elements seems to play a crucial role in the pathogenesis of RAS. Furthermore, the serum Cu/Zn and Cu/Se ratios may be used as biochemical markers in these patients.  相似文献   

6.
The bioavailability of trace elements in infant formulas is affected by different physiological and dietetic factors. In vitro methods based on element dialyzability have been proposed to estimate the bioavailability. Infant formulas of the same type but from different manufacturers can differ in the salt used for supplementation and in the contents of other components that can affect mineral bioavailability. The aim of our study is to estimate the dialyzability of iron, zinc, and copper of formulas marketed in Spain, in order to detect possible differences in formulas of the same type coming from different manufacturers. At the same time, the effects of the type of formula, the composition of the protein fraction, and the mineral content on the element dialyzability are also studied. Differences are found in the dialysis percentages of the elements studied in formulas of the same type but from different manufacturers. The formulas giving the highest dialysis percentages for the three considered elements are the hypoallergenic ones based on protein hydrolysates. No differences are observed in formulas having whey or casein as the main protein fraction. Significant correlations are obtained between the element contents and the dialyzability of the elements.  相似文献   

7.
Selenium, copper and zinc status is important in pregnant women. The aim of this study was to establish updated normal ranges for these elements in serum of pregnant women from the Spanish region of Aragon, and to study variation in levels with respect to gestational period and maternal age. The study group consisted of 159 pregnant women who did not suffer from serious pathologies. These samples were classified into four gestational-period groups. Zn and Cu determinations were obtained by flame atomic absorption spectroscopy in a Perkin-Elmer 1100B apparatus, and Se was determined by electrothermal atomic absorption spectrometry with Zeeman correction, in a Perkin-Elmer 4110 ZL apparatus. The concentrations of Cu, Zn and Se averaged 73.61±43.67 μg/dL, 65.37±12.87 μg/dL and 99.59±21.74 μg/L, respectively. The Cu/Zn ratio increased from first trimester to the third trimester (2.07–3.49). There was no significant correlation between Zn and Se levels, but a significant correlation was found between Cu and Se levels (p<0.05) and between Cu and Zn levels (p<0.001). Serum Zn and Se levels decreased over gestation, while serum Cu concentrations increased; in all cases the variation occurred mostly in the first 3 or 4 months, with mean levels then remaining fairly stable until the end of pregnancy. Maternal age did not influence levels of any of the three metals.  相似文献   

8.
ObjectivesThe objective of the present study was to assess trace element status in morbidly obese subjects before and one year after Roux-en-Y gastric bypass (RYGB) in order to identify possible deficiencies.MethodsThe study population included 46 patients in the age range 27–59 years, the majority (85 %) were women. The enrolled patients attended an eight week course on lifestyle changes before bariatric surgery. After RYGB they were recommended daily micronutrient supplements with a commonly used multivitamin-mineral tablet in addition to intramuscular vitamin B12 injections (1 mg) every third month for 12 months. Whole blood concentrations of Cu, Mn, Se and Zn were determined using high resolution inductively coupled plasma mass spectrometry.ResultsDuring the 12 months follow up after bariatric surgery, the patients had lost mean 32.3 kg and median whole blood concentrations of Cu (-16 %) were reduced, Mn (+14 %) and Zn (+6%) were increased, while the Se values were essentially unchanged. Compared with reference ranges, median postoperative concentrations of all essential trace elements were either below (Zn) or in the lower reference range (Cu, Mn, Se).ConclusionEssential trace elements were below or in the lower reference range twelve months after RYGB. Our results indicate a need for updated guidelines in Nordic countries for trace metal monitoring and supplements in patients after bariatric surgery, especially when gastric bypass surgery is used. Further studies are required to explore and prevent trace element deficiency related to obesity and bariatric surgery.  相似文献   

9.
Puberty associated with intense physical activity results in oxidation stress. Zinc supplementation may benefit antioxidant capacity although it may also affect iron and copper status. This study evaluated the effect of zinc supplementation on antioxidant, zinc and copper status of physically active male football players (13 years ± 0.4 years), divided in two groups and studied during 12 weeks: Zn‐supplemented (Zn‐SUP, 22 mg Zn d?1 as zinc gluconate, n = 21) and placebo (PLA, n = 26). At baseline, there was no significant difference in biochemical indices between the two groups. After treatment, plasma zinc and erythrocyte iron increased in both groups (p < 0.001); urinary zinc increased (p < 0.001) only in Zn‐SUP, and erythrocyte zinc decreased (p = 0.002) only in PLA. Plasma iron and copper decreased (p = 0.01 and p = 0.015, respectively) only in Zn‐SUP. Plasma ferric‐reducing ability and plasma conjugated dienes increased, and erythrocyte osmotic fragility decrease in both groups, although the latter two were significantly lower in Zn‐SUP compared to PLA (p < 0.01). In conclusion, our study indicates that the use of 22 mg d?1 of supplemental zinc during 12 week in adolescent athletes did not affect growth, improved markers of antioxidant status but reduced plasma iron and copper. Therefore, it appears that the use of zinc supplementation by healthy adolescent athletes benefits their antioxidant capacity but impairs copper and iron nutritional status. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
ObjectiveAdverse effects of lead exposure on children's health have been demonstrated. While studies have examined the relationship between iron status and low-level lead exposure in children with blood lead levels (BLLs) < 100 μg/L, few have investigated the association between blood lead and other trace elements and anemia in children with BLLs ≥ 100 μg/L. This study aimed to assess the levels of lead, iron, copper, zinc, magnesium, and calcium in children aged 0–14 with BLLs≥ 100 μg/L between 2009 and 2021, and to examine the relationship between blood lead, trace elements and anemia.MethodsA total of 11,541 children with BLLs ≥ 100 μg/L were included in this study. Venous blood samples were collected to measure blood lead levels, hemoglobin levels, and trace element levels. According to the World Health Organization standard, outpatients with hemoglobin levels < 110 g / L were defined as having anemia.ResultsThe study results found that high BLLs and blood calcium had a negative influence on Hb with odds ratios (95% confidence interval) of 1.411(1.208, 1.649) and 1.219(1.043, 1.424). High blood iron had a positive influence on Hb with odds ratios of 0.421(0.355, 0.499).ConclusionThe results suggest that the risk of anemia rose significantly with higher BLLs, blood copper, and blood calcium levels, and decreases considerably with higher blood iron levels.  相似文献   

11.
Dietary chitosans with different molecular weight Mw and the degree of deacetylation DDA (high molecular weight chitosan HCS with Mw 7.60 × 105 and DDA 85.5%, middle molecular weight chitosan MCS with Mw 3.27 × 104 and DDA 85.2%, chito-oligomer COS with Mw 0.99 × 103 and DDA 85.7% and water-soluble chitosan WSC with Mw 3.91 × 104 and DDA 52.6%) were used at the 1.05% level to feed mice for 90 days. Afterwards no pathological symptoms, clinical signs or deaths were observed. The body weight of mice in chitosan group and control group showed no significant difference. Although HCS, COS and WSC had no significant effect on the level of Fe, Zn and Cu in the tested mice’s liver, spleen, heart and kidney, MCS significantly increased the level of Fe, Zn and Cu in liver. Therefore dietary ingestion of chitosan did not depress the level of Fe, Zn and Cu in mice.  相似文献   

12.
We investigated the possible differences among the concentrations of copper, zinc, and selenium, and their mutual relations in the whole blood and thyroid tissue of patients with various thyroid disorders. Trace elements were determined by total-reflection X-ray fluorescence. The mean levels of these metals in blood as well as the mean Cu/Zn, Cu/Se, and Zn/Se ratios in the patients with thyroid cancer were significantly higher that in other patients and the control groups. However, the mean Zn and Se concentrations in the thyroid cancer tissue were significantly lower than in the thyroid tissue of other patients. In addition, the mean Cu/Zn and Cu/Se ratios in the thyroid cancer tissue were significantly higher than in the patients with other thyroid diseases. We confirm that the highest levels of copper and zinc as well as the Cu/Zn, Cu/Se, and Zn/Se ratios in the whole blood of the patients with thyroid cancer may suggest the progression of the proliferation process in the thyroid gland. We suggest that the low concentrations of zinc and selenium in the thyroid tissue confirm their participation in the carcinogenic process.  相似文献   

13.
BackgroundBariatric surgery is widely performed to improve obesity-related disorders, but can lead to nutrient deficiencies. In this study we examined serum trace element concentrations before and after bariatric surgery.MethodsWe obtained serum trace element concentrations by inductively coupled plasma-mass spectrometry (ICP-MS) method in 437 patients (82% women, median preoperative body-mass index 46.7 kg/m2 [interquartile range 42–51]) undergoing either gastric banding (22.7%), sleeve gastrectomy (20.1%), or gastric bypass (57.3%) procedures. Trace element data were available for patients preoperatively (n = 44); and 3 (n = 208), 6 (n = 174), 12 (n = 122), 18 (n = 39), 24 (n = 44) and 36 months (n = 14) post-operatively. All patients were recommended to take a multivitamin-mineral supplement after surgery.ResultsCopper deficiency was found in 2% of patients before surgery; and after surgery deficiency rates ranged from 0 to 5% with no significant change in median concentrations during follow-up (p = 0.68). Selenium deficiency was reported in 2% of patients before surgery; and after surgery deficiency rates ranged from 11 to 15% with a near-significant change in median concentrations (p = 0.056). Zinc deficiency was reported in 7% before surgery; and after surgery deficiency rates ranged from 7 to 15% with no significant change in median concentrations (p = 0.39).ConclusionsIn bariatric surgery patients recommended to take multivitamin-mineral supplements, serum copper, zinc and selenium concentrations were mostly stable during the first years after bariatric surgery. There was a possible tendency for selenium concentrations to decline during the early postoperative period.  相似文献   

14.
Two-wk-old broiler chicks were inoculated via crop intubation withEimeria acervulina at two doses: 105 or 106 sporulated oocysts/bird or withEimeria tenella at a dose of 105 sporulated oocysts/bird. Serum and liver samples were collected on days 3 and 6 post-inoculation (PI). There were no significant changes in serum or liver zinc, copper, and iron concentrations in any of the infected groups by 3 d PI. However, on d 6, PI serum protein was significantly reduced in all of the infected groups compared to their pair-fed controls. The chicks infected withE. tennella had significantly reduced serum zinc (1.20 vs 1.77 μg/mL) and iron (0.44 vs 1.28 μg/mL) concentrations and significantly elevated serum copper (0.28 vs 0.17 μg/mL) and ceruloplasmin levels (20.33 vs 11.11 μg/mL) compared to their pair-fed counterparts. Those chicks infected withE. acervulina (106 oocysts/bird) exhibited significantly reduced serum iron concentration by 6 days PI (0.90 vs 1.14 μg/mL). Liver zinc was significantly increased in the chicks infected withE. tenella (349 vs 113 μg/g dry liver wt), as was copper (24 vs 19 μg/g), whereas liver iron concentration was significantly reduced (172 vs 243 μg/g) compared to pair-fed controls. At both dose levels, the chicks infected withE. acervulina exhibited a significant reduction in liver iron by 6 d PI. Hepatic cytosol metals generally reflected whole tissue levels. Metallothionein (MT)-bound zinc was significantly elevated in the chicks infected withE. tenella. Iron bound to a high molecular weight, heat-stable protein fraction (presumably cytoplasmic ferritin) was significantly reduced in chicks infected withE. acervulina, as well as those infected withE. tenella. Collectively, the changes in serum zinc, copper, and iron concentrations, as well as the changes in hepatic zinc and MT-zinc concentrations in the chicks infected withE. tenella were similar to changes evoked during an acute phase response to infection. It is possible that a secondary bacterial infection or inflammation stemming from erosion of the lining of the cecum may play a role in the response of trace element metabolism to theE. tenella infection. Mentions of a trademarkr, proprietary product or specific equipment does not consitute a guarantee or warranty by the US Department of Agriculture and does not imply its approval to the exclusion of other products.  相似文献   

15.
BackgroundThe essentiality of trace elements in human diets is well recognized and adequate levels are a critical component of optimal health. To date, public health efforts have focused primarily on macronutrients or trace minerals that are easily analyzed. The goal of this research is to provide assessment of the dietary standards developed for Zn, Fe, and Cu in 100+ developed, marginal, and developing countries. We summarize the current recommendations and changes from the last decade, categorize and provide scientific basis for values established, factors that affect requirements, and current global challenges.MethodsThe electronic databases of Google Scholar, PubMed, Embase, Web of Science and Cochrane Library were searched using the keywords “trace minerals,” “micronutrients, ““zinc,” “iron,” “copper,” “dietary standards” and “recommendations.” A total of 123 studies published from 1965 to 2019 were included.ResultsThe World Health Organization (WHO) has established dietary standards to address nutrient deficiencies, prevent infections and ensure basic metabolic functions; these are utilized by most developing countries. Developed countries or their alliances have established values similar to or higher than the WHO, primarily for promotion of optimal health and well-being. Transitional countries are more concerned with issues of bioavailability, food security and undernutrition. Globally, Zn and Cu recommendations are lower in women than in men; Fe requirements are higher to compensate for menstrual losses. Important considerations in establishing guidelines for these minerals include bioaccessibility, dietary practices and restrictions, food processing, interactions, and chemical forms. The global challenges of the triple burden of malnutrition, hidden hunger, increased consumption of ultra-processed foods and obesity have been associated with Zn, Fe, and Cu deficiencies.ConclusionThis research provides public policy and health professionals evidenced-based information useful for the establishment of dietary standards world-wide.  相似文献   

16.
A number of essential trace elements play a major role in various metabolic pathways. Selenium (Se), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) are essential trace elements that have been studied in many diseases, including autoimmune, neurological, and psychiatric disorders. However, the findings of previous research on the status of trace elements in patients with schizophrenia have been controversial. We studied these elements in patients with a DSM-IV diagnosis of schizophrenia and compared them with sex- and age-matched healthy controls. Plasma Cu concentrations were significantly higher (p<0.01) and Mn and Fe concentrations were lower (p<0.05 and p<0.05, respectively) in schizophrenic patients than in controls. Se and Zn concentrations and protein levels did not differ between patients and healthy controls. These observations suggest that alterations in essential trace elements Mn, Cu, and Fe may play a role in the pathogenesis of schizophrenia. However, findings from trace element levels in schizophrenia show a variety of results that are difficult to interpret.  相似文献   

17.
Polyphenol-rich plant products as feed supplements have been shown to exert beneficial effects on feed efficiency in piglets. However, tannins as components of polyphenol-rich plant products are able to reduce the absorption of various trace elements. The present study investigated the effect of two polyphenol-rich dietary supplements, grape seed and grape marc meal extract (GME) and spent hops (SH), on iron (Fe), zinc (Zn) and copper (Cu) status in piglets supplied adequately with those trace elements. A trial with three groups of piglets which received a Control diet or the same diet supplemented with either 1% GME or 1% SH over a period of 4 weeks was performed. Concentrations of Fe, Zn and Cu in plasma, total iron binding capacity and saturation of transferrin in plasma did not differ between the three groups. Piglets fed the diet supplemented with SH showed no differences in the concentrations of Fe, Zn and Cu in the liver in comparison to the Control group. Piglets fed the diets supplemented with GME showed slightly lower concentrations of Zn and Cu in the liver than Control piglets (p < 0.05); however, concentrations of both elements remained in the physiological range. Overall, this study shows that the polyphenol-rich plant products GME and SH had marginal effect on the status of Fe, Zn and Cu in piglets.  相似文献   

18.
BACKGROUND AND AIM: Molecular diagnostics and therapeutics of human mesothelioma using disease-related markers present major challenges in clinical practice. To identify biochemical alternations that would be markers of human mesothelioma, we measured the intracellular steady-state levels of biologically important trace metals such as manganese (Mn), copper (Cu), and zinc (Zn) in a human mesothelial cell line, MeT-5A, and in five human mesothelioma cell lines (MSTO-211H, NCI-H226, NCI-H2052, NCI-H2452, ACC-MESO-1) by inductively coupled plasma-mass spectrometry (ICP-MS). We also aimed to investigate whether the alterations were related to the intracellular status of metal-containing superoxide dismutase (SOD). RESULTS: There were no significant differences in the contents of the trace metals among MeT-5A, MSTO-211H, and ACC-MESO-1 cells. However, each of the other three mesothelioma cell lines had a unique characteristic in terms of the intracellular amounts of the metals; NCI-H226 contained an extremely high level of Mn, an amount 7.3-fold higher than that in MeT-5A. NCI-H2052 had significantly higher amounts of Cu (3.4-fold) and Zn (1.3-fold) compared with MeT-5A. NCI-H2452 contained about 5.8-fold the amount of Cu and 2.5-fold that of Mn compared with MeT-5A. As for the intracellular levels of copper/zinc-SOD (Cu/Zn-SOD) and manganese-SOD (Mn-SOD), those of Cu/Zn-SOD were relatively unchanged among the cells tested, and no notable correlation with Cu or Zn contents was observed. On the other hand, all mesothelioma cells highly expressed Mn-SOD compared with MeT-5A, and a very high expression of the enzyme with a robust activity was observed in the two mesothelioma cells (NCI-H226, NCI-H2452) containing a large amount of Mn. CONCLUSIONS: In comparison with MeT-5A human mesothelial cells, some human mesothelioma cells had significantly higher amounts of Mn or Cu and one mesothelioma cell had a significantly higher amount of Zn. Interestingly, all mesothelioma cells overexpressed Mn-SOD compared with MeT-5A, and the cells whose Mn-SOD activity was increased contained higher amounts of Mn. It seemed that intracellular Mn content was positively correlated with Mn-SOD, suggesting that the intracellular Mn level is associated with Mn-SOD activity. These biochemical signatures could be potential disease-related markers of mesothelioma.  相似文献   

19.
In the present study, the serum and hair levels of zinc, selenium, and copper were determined in children with iron-deficiency anemia (IDA). A total of 52 anemic children aged 1–4 yr constituted the study group. Fortysix healthy children acted as controls. The copper and zinc levels were measured with an atomic absorption spectrophometer. Serum and hair selenium was determined by a spectroflourometric method. The serum zinc and selenium concentrations in the IDA group were found to be significantly lower and serum copper significantly higher than those in the controls (p<0.05). Lower iron, zinc, and selenium concentrations (p<0.001) but not copper were found in hair (p>0.05).  相似文献   

20.
Biological Trace Element Research - Female guinea pigs were exposed to 10 doses of 3 mg/kg body weight of methylmercuric chloride with or without concomitant equimolar doses of sodium selenite....  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