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1.
The purpose of this study was: 1) to establish the prevalence of depleted iron stores, iron deficiency, and low serum levels for copper, zinc, calcium, and magnesium in a healthy female population; and 2) to examine the effects of iron supplementation and discontinuation on the serum levels of the above minerals. One hundred eleven healthy women between the ages of 18 and 40 yr reported for fasted morning blood sampling for iron, copper, zinc, calcium, and magnesium status. Forty-five subjects were either iron-deficient as defined by a hemoglobin level below 120 g.l-1 (four subjects) or iron deplete as defined by a serum ferritin value below 20 micrograms.l-1 (43 subjects). Two subjects fit both criteria. This subgroup continued with the study and were prescribed a normal therapeutic iron dose (320 mg elemental iron per day, taken as two Slow-Fe tablets.d-1 for a period of 12 wk). The subjects then discontinued the iron supplementation for a further 12 wk. The response of the various blood minerals was monitored at 6-wk intervals. Twenty-five subjects completed the full 24-wk treatment. The main conclusions to be made from this study were that: 1) For this sample population of women, iron depletion was quite common (39%), although low hemoglobin values (< 120 g.l-1) were only seen in 3.6%. No subjects fell below the criteria for low serum copper levels (< 13.3 mumol.l-1) nor low serum magnesium levels (< 0.6 mmol.l-1). Seven subjects (6.5%) fell below the criteria for low serum zinc levels (< 11.5 mumol.l-1) while two subjects (1.8%) were below the criteria for low serum calcium levels (< 2.20 mmol.l-1). 2) Therapeutic oral iron supplementation was successful in raising mean serum ferritin values from 15.9 micrograms.l-1 to 36.5 micrograms.l-1 but was not associated with decrements in serum copper or calcium levels. 3) The treatment did not significantly effect serum zinc and magnesium levels during the supplementation period, but a downward trend continued through the discontinuation phase so that at 18 and 24 wk serum zinc and magnesium levels were significantly lower than baseline. 4) Oral contraceptive use was associated with elevated serum copper and ferritin values and lowered serum magnesium levels.  相似文献   

2.
To clarify the changes of mineral levels in different tissues of riboflavin-deficient rats, Wistar rats were separated into three groups. One group was fed a diet ad libitum that was deficient in riboflavin. The other two were fed either the complete diet that was weight-matched to the riboflavin-deficient group or fed a complete diet ad libitum. In riboflavin-deficient rats, the hemoglobin concentration and riboflavin contents of blood, liver, and kidney were significantly decreased, compared with weight-matched and ad libitum-fed controls. The mineral concentrations of tissues are summarized as follows: The iron (Fe) concentration in the heart, liver, and spleen was decreased in the riboflavin-deficient group compared with the other groups. Calcium (Ca) and magnesium (Mg) concentrations in tibia were decreased in the riboflavin-deficient group compared with the other two groups. Copper (Cu) concentration was increased in the heart and liver, when the riboflavin-deficient group was compared with the other groups. Zinc (Zn) concentration was increased in tibia when the riboflavin-deficient group was compared with the other groups.  相似文献   

3.
采用盐酸溶解样品,选择Co 240.72nm、Cu 324.75nm、Zn 213.86nm、Fe 248.33nm、Ca 422.67nm、Mg 202.58nm作为分析谱线,钴、铜、锌、铁选择3个像素点,钙、镁选择9个像素点,建立了连续光源原子吸收光谱法(CS-AAS)同时测定氧化镍中的钴、铜、锌、铁、钙、镁的方法。实验表明:在100mL测定液中加入2mL 200g/L氯化锶溶液,可消除测定介质(体积分数为2%的盐酸)对待测元素的影响;基体镍对测定的干扰可忽略。在优化的实验条件下,钴、铜、锌、铁、钙、镁的校准曲线相关系数均不低于0.999 0,且其方法检出限在0.002~0.092μg/mL之间。按照实验方法对氧化镍样品中钴、铜、锌、铁、钙、镁分别平行测定11次,钙和镁的测定值在0.1%~0.4%之间,其对应的相对标准偏差(RSD)不大于2%;钴、铜、锌、铁的测定值在0.003%~0.04%之间,其对应的相对标准偏差均小于10%。将实验方法应用于电真空镍光谱标准样品(该标样为氧化镍状态)中上述各元素的测定,结果与认定值基本一致。  相似文献   

4.
The purpose of this study was to undertake a critical review of the potential role of magnetic resonance imaging (MRI) in the evaluation of low back pain (LBP) and to determine if there were differences in the MRI appearances between various occupational groups. The study group, 149 working men (78 aged 20-30 years and 71 aged 31-58 years) from five different occupations (car production workers, ambulance men, office staff, hospital porters and brewery draymen), underwent MRI of the lumbar spine. Thirty-four percent of the subjects had never experienced LBP. Twelve months later, the examination was repeated on 89 men. Age-related differences were seen in the MRI appearances of the lumbar spine. Disc degeneration was most common at L5/S1 and was significantly more prevalent (P < 0.01) in the older age group (52%) than in the younger age group (27%). Although LBP was more prevalent in the older subjects there was no relationship between LBP and disc degeneration. No differences in the MRI appearance of the lumbar spine were observed between the five occupational groups. Overall, 45% had 'abnormal' lumbar spines (evidence of disc degeneration, disc bulging or protrusion, facet hypertrophy, or nerve root compression). There was not a clear relationship between the MRI appearance of the lumbar spine and LBP. Thirty-two percent of asymptomatic subjects had 'abnormal' lumbar spines and 47% of all the subjects who had experienced LBP had 'normal' lumbar spines. During the 12-month follow-up period, 13 subjects experienced LBP for the first time. However, there was no change in the MRI appearances of their lumbar spines that could account for the onset of LBP. Although MRI is an excellent technique for evaluating the lumbar spine, this study shows that it does not provide a suitable pre-employment screening technique capable of identifying those at risk of LBP.  相似文献   

5.
A zinc oxide and eugenol root canal sealer (Roth 811) and sterile saline solution were injected into the dorsal thoracic midline of 70 male Wistar-Furth rats. Every day for the next 7 days, 10 animals were sacrificed by either inhalation. The liver, heart, kidneys and brain were removed from the animals and analysed for zinc, calcium and copper concentrations by flame atomic absorption spectrophotometry. The tissue around the injection site was also surgically removed and prepared for histological evaluation under a microscope. The injection of Roth 811 significantly affected the concentrations of zinc, calcium and copper in some of the examined organs, especially on the 4th and 5th day. The inflammatory reaction adjacent to the material was severe during the first 3 days while on the 7th day the presence of connective tissue with collagen formation was observed.  相似文献   

6.
The interaction of magnesium with two other mineral elements, calcium and zinc, was studied in maternal tissues and fetuses of pregnant rats fed a magnesium deficient diet throughout gestation. Reduction in maternal femur magnesium and a trend for increased kidney calcium reflected the dietary magnesium deficiency. In fetuses, however, total magnesium content was reduced and , in addition, fetal zinc content was also lower than normal in the group most severly deficient in magnesium. The possible interpretation of this magnesium-zinc interaction is discussed.  相似文献   

7.
BACKGROUND/AIM: Hepatic tumors with elements of both hepatocellular and cholangiocellular carcinoma are occasionally encountered; however, the independent and simultaneous occurrence of different epithelial malignant tumors in different lobes is rare. This is a case report of resected double cancer in different lobes of the liver. MATERIALS AND METHODS: A 73 year old Japanese man, with hepatic mass and a history of peritonitis and hepatitis, underwent laparotomy and hepatic resection of the posterior inferior and the left lateral segment, and cholecystectomy for cholecystlithiasis with left-sided gallbladder at our hospital in 1991. RESULTS: The tumor, located in the posterior inferior segment, a yellow-white, round, highly circumscribed mass with a thick capsule, was about 9.0 by 8.0 cm in size. The other tumor located in the left lateral segment, grayish-white on the cut section, was approximately 5.0 by 4.0 cm. CONCLUSION: In our case, it is unlikely the tumor in the right lobe metastasized to the left lobe and transformed into a different type. The two tumors showed clearly different microscopic features. Improved imaging will increase the frequency and number of double cancer diagnosis. This additional data may shed light on the pathogenesis and etiology of double cancer.  相似文献   

8.
邓冬莉  李芬  向敏婕  吴祎  邓灏 《冶金分析》2016,36(12):26-31
油类样品易燃易爆,在对其中较低含量金属元素进行分析时极易引起被测元素损失且一般进样系统无法对其直接测定,因此测定时样品的前处理过程非常重要。实验取100 mL航空煤油样品于500 mL分液漏斗中,加入2.0 mL碘-二甲苯溶液和15 mL硝酸(1+9)重复萃取2次,将两次萃取液合并后再用10 mL水萃取一次,萃取液浓缩后采用火焰原子吸收光谱法(FAAS)进行测定,建立了测定航空煤油中铅、锰、镁、锌和铜5种元素含量的方法。结果表明:铅、锰、镁、锌和铜5种金属元素校准曲线的相关系数均大于0.999 0,方法检出限为0.009~0.256 μg/mL。采用实验方法对航空煤油样品进行测定,测定结果与电感耦合等离子体原子发射光谱法(ICP-AES)基本一致,相对标准偏差(RSD,n=9)为0.86%~5.4%。将实验方法应用于4个不同产地的航空煤油样品中铅、锰、镁、锌和铜的测定,各个元素的加标回收率均在96%~103%之间。  相似文献   

9.
BACKGROUND: Animal experiments and epidemiological studies have suggested that high potassium intake may reduce the risk of stroke, but the evidence is inconclusive, and the role of other nutrients in potassium-rich foods remains unknown. METHODS AND RESULTS: We examined the association of potassium and related nutrients with risk of stroke among 43 738 US men, 40 to 75 years old, without diagnosed cardiovascular diseases or diabetes, who completed a semiquantitative food frequency questionnaire in 1986. During 8 years of follow-up, 328 strokes (210 ischemic, 70 hemorrhagic, 48 unspecified) were documented. The multivariate relative risk of stroke of any type for men in the top fifth of potassium intake (median intake, 4.3 g/d) versus those in the bottom (median, 2.4 g/d) was 0.62 (95% CI, 0.43, 0.88; P for trend=0.007). Results for ischemic stroke alone were similar. Intakes of cereal fiber and magnesium, but not of calcium, were also inversely associated with risk of total stroke. These inverse associations were all stronger in hypertensive than normotensive men and were not materially altered by adjustment for blood pressure levels. Use of potassium supplements was also inversely related to risk of stroke, particularly among men taking diuretics (relative risk, 0.36; 95% CI, 0.18, 0.72). CONCLUSIONS: Although these data do not prove a causal relationship, they are consistent with the hypothesis that diets rich in potassium, magnesium, and cereal fiber reduce the risk of stroke, particularly among hypertensive men. Potassium supplements may also be beneficial, but because of potential risks, use should be carefully monitored and restricted to men taking potassium-losing diuretics.  相似文献   

10.
硫酸锌溶液冷却结晶除钙镁生产实践   总被引:3,自引:0,他引:3  
对几种不同的除钙镁工艺进行了对比分析,研究了冷却沉降法除硫酸锌溶液中的Ca、Mg,实验表明,冷却沉降法是一种节能、高效的工艺方案,控制温度25℃、pH=3.8~4.5、晶种加入量4 g/L、沉降时间100 min,可获得较好的工艺指标。  相似文献   

11.
The kinetics of gold cementation by magnesium aluminum, zinc, iron and copper at equal conditions as well as the morphology of cementation products and the dissolution of cementing agents were investigated. Both the effect of cementing agents on gold cementation rate and the dissolution of metals decrease in order Cu > Zn > Mg > Fe > Al. High dissolution of magnesium, zinc, iron and copper per mol deposited gold was found. Zinc is the most efficient cementing agent. Magnesium and iron can be used in gold cementation practice but the extremely slow cementation rate prevents the practical application of aluminum.Significant differences in the morphology of gold deposits on magnesium, aluminum, zinc, iron and copper were found: thick deposit layers with small or large cracks were observed on magnesium or zinc; porous layers of fern leaf-shaped dendrites on copper; compact smooth deposit of fine crystallites on iron and small very rare formations of fine dendrites on aluminum.  相似文献   

12.
在电炉上将样品碳化至无烟后将铂坩埚置于高温炉内于750 ℃下灼烧约6 h进行灰化,采用四硼酸锂(Li2B4O7)熔融、5%硝酸溶解,以5 mL 100 mg/mL镧溶液为释放剂,建立了火焰原子吸收光谱法(FAAS)测定针状石油焦样品中钾、铅、镁、锌、铜、锰的方法。实验表明,针状石油焦样品中其他元素不干扰待测元素的测定,待测元素间无相互干扰。在选定的最佳仪器条件下,钾、铅、镁、锌、铜、锰的检出限分别为0.008、0.030、0.001、0.005、0.008、0.007 μg/mL。采用实验方法对2批针状石油焦样品进行测定,结果与电感耦合等离子体发射光谱法(ICP-AES)基本一致,相对标准偏差(n=10)为0.63%~3.4%,加标回收率在98%~104%之间。  相似文献   

13.
The binding isotherms of the divalent metal cations, Ca2+, Mg2+, and Zn2+, to the synthetic gamma-carboxyglutamic acid-containing neuroactive peptides, conantokin-G (con-G) and conantokin-T (con-T), have been determined by isothermal titration calorimetry (ITC) at 25 degreesC and pH 6.5. We have previously shown by potentiometric measurements that con-G contains 2-3 equivalent Ca2+ sites with an average Kd value of 2800 microM. With Mg2+ as the ligand, two separate exothermic sites are obtained by ITC, one of Kd = 46 microM and another of Kd = 311 microM. Much tighter binding of Zn2+ is observed for these latter two sites (Kd values = 0.2 microM and 1.1 microM), and a third considerably weaker binding site is observed, characterized by a Kd value of 286 microM and an endothermic enthalpy of binding. con-T possesses a single exothermic tight binding site for Ca2+, Mg2+, and Zn2+, with Kd values of 428 microM, 10.2 microM, and 0.5 microM, respectively. Again, in the case of con-T, a weak (Kd = 410 microM) endothermic binding site is observed for Zn2+. The binding of these cations to con-G and con-T result in an increase in the alpha-helical content of the peptides. However, this helix is somewhat destabilized in both cases by binding of Zn2+ to its weakest site. Since the differences observed in binding affinities of these three cations to the peptides are substantially greater than their comparative Kd values to malonate, we conclude that the structure of the peptide and, most likely, the steric and geometric properties imposed on the cation site as a result of peptide folding greatly influence the strength of the interaction of cations with con-G and con-T. Further, since the Zn2+ concentrations released in the synaptic cleft during excitatory synaptic activity are sufficiently high relative to the Kd of Zn2+ for con-G and con-T, this cation along with Mg2+, are most likely the most significant metal ion ligands of these peptides in neuronal cells.  相似文献   

14.
活性炭样品经550 ℃高温焙烧后,以硝酸、氢氟酸和盐酸的混酸作为消解试剂,用微波消解法消解,电感耦合等离子体原子发射光谱法(ICP-AES)测定消解液中铁、锌、钙、镁和铅金属元素含量。试验结果表明:样品经高温焙烧后基体元素碳已除去,对测定没有干扰,因此可以直接用待测元素的标准溶液绘制校准曲线,不需要进行基体匹配。共存元素由于含量很低,在所选定的分析线下测定也没有干扰。方法的检出限如下:铁为0.02 μg/mL,锌为0.01 μg/mL、钙为0.01 μg/mL、镁为0.02 μg/mL,铅为0.05 μg/mL。样品测定结果的相对标准偏差(RSD)在1.7%~4.1%之间(n=9),回收率在94%~96%之间。  相似文献   

15.
The possible association between the risk of rectal cancer and the levels of calcium and magnesium in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. All eligible rectal-cancer deaths (986 cases) of Taiwan residents from 1990 through 1994 were compared with a sample of deaths from other causes (986 controls), and the levels of calcium and magnesium in the drinking water of these residents were determined. Data on calcium and magnesium levels in drinking water throughout Taiwan were obtained from the Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes, and the controls were pair-matched to the cases by gender, year of birth and year of death. Compared with those with calcium levels below 22.0 mg/liter, the adjusted odd ratios (95% confidence interval) were 0.72 (0.53-0.98) for the group with water calcium levels between 22.0 and 40.8 mg/liter and 0.63 (0.45-0.87) for the group with calcium levels of 40.9 mg/liter or more. The adjusted odd ratios were not statistically significant for the relationship between magnesium levels in drinking water and rectal cancer. The results of the present study show that there may be a significant protective effect of calcium intake from drinking water on the risk of rectal cancer.  相似文献   

16.
The effect of long-term supplementation with CaCO3 on indices of Fe, Zn and Mg status was investigated in a randomized, double-blind intervention study of sixty lactating Gambian women. The supplement contained 1000 mg Ca and was consumed between meals 5 d/week, for 1 year starting 1.5 weeks postpartum. Compliance was 100%. Plasma ferritin concentration, plasma Zn concentration and urinary Mg output were measured before, during and after supplementation at 1.5, 13, 52 and 78 weeks postpartum. No significant differences in mineral status were observed at any time between women in the supplement and placebo groups. Analysis of the longitudinal data series showed that plasma ferritin and Mg excretion were characteristic of the individual (P < 0.001). Within individuals, ferritin concentration was higher at 1.5 weeks postpartum than later in lactation (P = 0.002). Plasma Zn concentration was lower at 1.5 weeks postpartum than at other times (P < 0.001), an effect which disappeared after albumin correction. Low plasma concentrations of ferritin and Zn indicated that the Gambian women were at high risk of Fe and Zn deficiency. Measurements of alpha 1-antichymotrypsin suggested that the results were not confounded by acute-phase responses. The results of the present study indicate that 1000 mg Ca as CaCO3 given between meals does not deleteriously affect plasma ferritin and Zn concentrations or urinary Mg excretion in women who are at risk of Fe and Zn deficiency.  相似文献   

17.
OBJECTIVE: To establish similarities or differences in tissue concentrations of zinc, copper, and iron in Bull Terriers with lethal acrodermatitis (LAD) and tail-chasing behavior (TCB) and to confirm the suspicion that copper is involved in the etiopathogenesis of LAD. SAMPLES: Serum samples from 29 Bull Terriers (9 control dogs, 6 dogs with LAD, 14 dogs with TCB), and liver and kidney specimens from 2 dogs and 1 and 4 dogs with LAD or TCB, respectively. PROCEDURE: Serum, liver, and kidney mineral (zinc, copper, and iron) concentrations in Bull Terriers with LAD or TCB and in a group of control dogs were analyzed, using flame atomic absorption after wet ashing technique. RESULTS: Serum zinc and copper concentrations were lower (P < 0.05) in dogs with LAD, compared with values for control dogs and dogs with TCB. Liver zinc and copper concentrations were similar to serum values. Kidney zinc and copper concentrations were similar among the 3 groups. Serum, liver, and kidney iron concentrations had a wide range of variability within all 3 groups. CONCLUSION: Copper deficiency is associated with LAD. The primary cause of LAD may be copper deficiency, with zinc involved secondarily, or combined zinc and copper deficiencies. The role of ion deficiency in TCB was not clarified. CLINICAL RELEVANCE: Serum zinc and copper concentrations should be determined when LAD is suspected.  相似文献   

18.
19.
李佗  杨军红 《冶金分析》2012,32(2):70-72
石煤矿试样经HNO3 、 HCl 、 HF 和 HClO4混酸[V(HNO3)∶V( HCl)∶V(HF)∶ V(HClO4)=1∶3∶2∶3]溶解后,采用电感耦合等离子体原子发射光谱法测定试样中V、Mg、Zn、Fe、Cu、Mn含量。选择波长为210230 nm,285213 nm,213856 nm,259940 nm,327396 nm,257610 nm的谱线分别作为V、Mg、Zn、Fe、Cu、Mn的分析线,共存元素对测定没有影响,基体元素Si在溶样时以SiF4挥发而除去。在优化的实验条件下对石煤矿试样中上述元素进行测定,测定结果的相对标准偏差(RSD,n=5)在098%~21%范围,回收率在94%~102%之间。  相似文献   

20.
成勇 《冶金分析》2016,36(2):65-70
采用盐酸溶解样品,使用基体匹配法配制校准曲线消除基体效应的影响,选择Ca 317.933 nm、Mg 285.213 nm、Ni 211.647 nm、Cu 324.754 nm、Al 396.152 nm、Fe 238.204 nm作为分析线,电感耦合等离子体原子发射光谱法(ICP-AES)测定硫酸氧钒中钙、镁、镍、铜、铝、铁。进行了1.6 mg/mL钒离子和3.0 mg/mL硫酸根共存体系中基体效应、光谱干扰和连续背景叠加对待测元素测定的影响试验。结果表明,该质量浓度的硫酸根离子对测定不产生影响,而钒对部分待测元素谱线产生光谱干扰,钒基体效应对待测元素均产生正干扰。采用钒基体匹配和同步背景校正相结合的方式消除钒基体的影响,并且优选出未受光谱干扰的各待测元素分析谱线及其背景校正和检测区域,根据试验结果确定了ICP-AES工作条件。钙、镁、镍、铜、铝、铁的质量分数在0.000 1%~0.10%范围内与发射强度成线性,各元素校准曲线的相关系数均大于0.999,背景等效浓度为-0.000 3%~0.000 4%,方法中各元素的检出限为0.000 1%~0.000 3%(质量分数)。按照实验方法测定硫酸氧钒中钙、镁、镍、铜、铝、铁,结果的相对标准偏差(RSD,n=8)为2.6%~14%。实验方法用于测定2个硫酸氧钒样品中钙、镁、镍、铜、铝、铁,结果与电感耦合等离子体质谱法(ICP-MS)的测定结果相吻合。  相似文献   

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