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1.
The effect of age and gender on chemical element contents in intact crowns of permanent teeth of 84 apparently healthy 15–55 year old women (n = 38) and men (n = 46) was investigated. Mass fractions of Ca, Cl, K, Mg, Mn, Na, P, and Sr in crowns were determined by instrumental neutron activation analysis using short-lived radionuclides. Mean values (M ± SΕΜ) for female and male combined were (on dry weight basis): 350 ± 5 g/kg, 2920 ± 150 mg/kg, 839 ± 80 mg/kg, 4880 ± 240 mg/kg, 3.20 ± 0.30 mg/kg, 6240 ± 140 mg/kg, 181 ± 4 g/kg, and 293 ± 24 mg/kg respectively. A statistically significant decrease of Sr (P ≤ 0.01) and increase of Na (P ≤ 0.01) content in the tooth crowns with age was found for women. Sex-related comparison did not show any differences.  相似文献   

2.
Summary Concentration of Ca, Cl, K, Mg, Mn, Na, P, and Sr were determined by instrumental neutron activation analysis using short-lived radionuclides in intact cortical and trabecular bone of femoral neck and iliac crest of 81 relatively healthy 15-55 years old women (n = 36) and men (n = 45). In cortical bone the Ca, P, and Mg mass fractions in the femoral neck were statistically significantly higher, and Cl, K, and Na lower, than the values for the iliac crest. In trabecular bone the Cl, K, and Na mass fractions in the iliac crest were significantly higher, and Ca, P also higher, than the values for the femoral neck.  相似文献   

3.
The Volta clam Galatea paradoxa is a highly priced shellfish providing nutrition, jobs and poverty alleviation for the inhabitants of the lower Volta estuary. Clams are filter feeders straining particulate materials in the surrounding water, thus concentrating microorganisms and other metal elements in the gut and mantle which present possible health hazards. The elemental composition of the water, clam mantle, gut, shell, and bottom sediments were determined using Neutron Activation Analysis for the presence of Ca, Cl, Cu, Mg, Mn, V, Fe, Co, Br, Na and K. Proximate analysis of the mantle for the levels of protein, fat, carbohydrate, ash, wood fiber, phosphorus, free fatty acids and energy were carried out using the method of the Association of Official Analytical Chemists. The riverine water was laden with heavy metals V, Co, Cu, Mn, and Fe, as well as Al. These same metallic elements were detected in higher concentrations in the bottom sediments. Bioaccumulation factor (BAF) which is the measure of the distribution of heavy metals between water and biota (Clam mantle and gut), ranged from 2 to 145 times, depending on the type of contaminant. The clam meat contained high protein (15.3 ± 0.2%), no crude fiber, low fat content (1.80 ± 0.11%), fatty acids as oleic (25.2 ± 0.1%), energy (85.5 ± 0.21 kcal/100 g), carbohydrates (22.10 ± 0.03%), P (485 ± 1 mg/100 g), Ca (793 ± 75 mg/kg), Mg (860.3 ± 90.0 mg/kg). The high concentration of Ca (21,402.7 ± 797.0 mg/kg), Fe (18,071.2 ± 94.0 mg/kg), K (96 ± 14 mg/kg), Mg (540.8 ± 81.1 mg/kg), Na (4,570.0 ± 0.2 mg/kg) gives credence to the use of the shell for poultry feed mineral supplements, and in the emulsion paint manufacturing industry.  相似文献   

4.
The determination of fluorine, calcium and phosphorus in bone by instrumental fast neutron activation analysis is described. Results for the IAEA standard material “Animal Bone” A3-74 re: Ca=313±10 mg/g, P=155±5 mg/g and F-613±20μg/g. The accuracy for all three elements is≤4%, precision being about 3%. The limit of determination for F is 120 μg, for Ca 30 mg and for P 1 mg in a sample of 500 mg.  相似文献   

5.
The mechanical strength of bone depends first of all on the condition of the cortical bone. In the present study the Ca/P ratio was estimated in intact cortical bone samples from iliac crest of healthy humans, 36 women and 44 men, aged from 15 to 55 years using INAA. No statistically significant differences (p>0.05) were observed of age- or sex-related Ca/P ratio. The mean value (M±SD) of the Ca/P ratio for the whole group studied, 2.21±0.29, was within the range of published data and close to the median value. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

6.
Mineral contents of strawberry, collected from different farms of Islamabad were analysed by semi-absolute k 0-instrumental neutron activation analysis and atomic absorption spectrophotometry. The samples were irradiated at two research reactors located in Pakistan Institute of Nuclear Science & Technology (PINSTECH), Islamabad. The analytical methodologies were validated by analysing reference materials, IAEA-336 (lichen) and IAEA-V-10 (hay powder). In all the samples, a total of 26 elements were quantified, among them 16 elements (Ca, Cd, Cl, Co, Cr, Cs, Fe, K, Mg, Mn, Na, Pb, Ru, Sc, Sr and Zn) were found in all the samples. The determined elemental concentrations in strawberry were compared with the reported values from other countries. In comparison with the mineral contents of other fruits, strawberry stands best source of Mn and the second most important source of K after banana. Intake of trace metals through this source was calculated and it was found that strawberry provides Mn (1.95–3.68 mg/kg), Cr (19.2–46.3 × 10−3 mg/kg), Fe (3.45–8.72 mg/kg), K (1,520–1,670 mg/kg) and Mg (100–220 mg/kg), which forms 26, 19, 14, 7 and 7% of the recommended dietary allowances for the respective metals. The daily intake of Cd and Pb were compared with the provisional tolerable weekly intake defined by FAO/WHO.  相似文献   

7.
The effect of age and sex on eight elements in cortical bone of femoral neck of 78 relatively healthy 15-55 years old women (n = 33) and men (n = 45) was studied. Mass fraction of Ca, Cl, K, Mg, Mn, Na, P, and Sr in intact bone samples were determined by instrumental neutron activation analysis using short-lived radionuclides. The obtained results were in good agreement with the literature data with the exception of Mn and Sr. The mean value of Mn mass fraction was an order of magnitude lower and Sr mean mass fraction was in 1.5-5 times higher than the reference values. No age- and sex-related differences in bone composition were detected. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

8.
In this study the neutron activation analysis (NAA) technique was applied to determine Ca and Mg in whole blood from inhabitants of Brazil for the purpose of establishing concentration ranges indicative of sex and age. The initiative to perform these measurements is related to the increase in heart disease. According to recent statistics from WHO, the average is one death due to heart attack in Brazil, every five minutes. The measures were performed considering lifestyle factors (non-smokers, non-drinkers and no history of toxicological exposure) of Brazilian inhabitants. A healthy group constituted of male (n = 94) and female (n = 84) blood donors, ages between 18 and 70 years and above 50 kg, was selected from the blood banks and hematological laboratories of Brazil. The influence of sex was also investigated considering several age ranges (18–29, 30–40, 41–50, >50 years). The results show significant differences when a comparison is made by sex and age and may be useful to identify or prevent clinical diseases. These results emphasize the need to perform periodic evaluation of Ca and Mg in blood.  相似文献   

9.
The effect of age on chemical element contents in intact prostate of 64 apparently healthy 13–60 years old men was investigated by neutron activation analysis with high resolution spectrometry of short-lived radionuclides. Mean values (M ± SΕΜ) for content (mg/kg, dry weight basis) of chemical elements were: Br–31.6 ± 3.2, Ca–2150 ± 160, Cl–12670 ± 675, K–12010 ± 400, Mg–1150 ± 75, Mn–1.56 ± 0.09, and Na–10520 ± 340, respectively. A tendency of age-related increase in Ca content and decrease in Mn content was observed.  相似文献   

10.
The report considers the results of the development of the automated technique for simultaneous, multielement activation analysis of plants and fertilizers for the macronutrient elements N, P, K, Ca, Mg, Cl, and Si. On the basis of analytical procedures, algorithms and software developed, the first automatic (computer based) installation for multielement analyses of plants and fertilizers has been completed and is in routine use in the agrochemical and plant breeding research program at Soviet Union. The proposed technique together with the full automatic real time process of measurement and processing of data by computer, provides a throughput of 250–500 samples (1250–2500 elements determinations) per 8-hour shift, with the accuracy of ±3% for N and ±5–10% for P, K, Mg, Cl and ±15% for Ca.  相似文献   

11.
A nondestructive NAA method based on the reaction 31P(n,γ)32P (T 1/2 = 14.23 d) has been developed where the product nucleus, a pure β-emitter with end point energy 1.71 MeV is measured by using an end window G.M. counter and an Al filter of 27 mg·cm−2. 32P was identified by measuring E β using Feather’s analysis and its half-life was found to be 15.3±0.2 days in standard reference materials (SRMs) and samples. For most reference materials (RMs) from NIST (USA) and IAEA (Vienna), our values agree within ±5% of the certified values. A variety of biological samples have also been analyzed and our values are in the range; medicinal herbs (n = 43), 0.29–5.23 mg/g; bhasmas (n = 19), 0.09–51.4 mg/g; vegetables (n = 8), 1.85–5.73 mg/g; lentils (n = 6), 2.1–5.5 mg/g; flours (n = 6), 1.3–3.3 mg/g; vegetarian diet (n = 5), 2.41–2.90 mg/g; fish (n = 43), 3.61–36.8 mg/g; human and animal milk (n = 6), 1.24–7.95 mg/g; commercial milk powders (n = 14), 2.76–11.9 mg/g; water from various sources (n = 14), 1–417 μg/l; human and animal blood (n = 9), 1.00–15.0 mg/g; cancerous and healthy breast tissue (n = 60), 1.00–8.63 mg/g; human hair (n = 43), 0.12–5.81 mg/g, where n is the number of samples analyzed. The method is simple, fast, and nondestructive and provides data within ±5% error limit with a detection limit of 0.1 mg/g.  相似文献   

12.
Proton-induced prompt gamma-ray emission (PIGE) analysis has been used for the determination of light elements in human dense bone samples. Li, B, N, O, F, Na, Mg, Al, P and Ca peaks were detected. Smoothed, freeze-dried samples were irradiated in vacuo by 2.4 MeV protons and the induced prompt gamma rays recorded with a 110 cm3 Ge(Li) detector. Absolute concentrations were calculated on the basis of both calibration standards and pure element gamma-ray yields. The mean (±1 S. D.) concentrations as ppm or weight % obtained for 15 dense bone samples were: B 8.0 (3.3)ppm, N 12.2 (0.8)%, O 34.8 (2.3)%, F 639 (417)ppm, Na 5763 (371)ppm, Mg 2078 (290)ppm, P 9.26 (0.50)% and Ca 20.4 (1.3)%. The detection limits obtained without any prior concentration of the bone samples were: 0.3 ppm for Li, 2.0 ppm for B, 1.0% for N, 1.0% for O, 1.0 ppm for F, 3.0 ppm for Na, 50 ppm for Mg, 22 ppm for Al, 600 ppm for P and 0.8% for Ca. Detection limits for other light elements (4≤Z≤21) have also been estimated.  相似文献   

13.
A flow injection method is described for the determination of iron in fresh water based on potassium permanganate chemiluminescence detection via oxidation of formaldehyde in aqueous hydrochloric acid. Total iron concentrations are determined after reducing Fe(III) to Fe(II) using hydroxylamine hydrochloride. The detection limit (three standard deviations of blank) is 1.0 nM, with a sample throughput of 120 h−1. The calibration graph was linear over the range (2–10) × 10−7 M (r 2 = 0.9985) with relative standard deviations (n = 5) in the range 1.0–2.3%. The effect of interfering cations (Ca(II), Mg(II), Zn(II), Ni(II), Co(II), Fe(III), Mn(II), Pb(II), and Cu(II)) and common anions (Cl, SO 4 2− , PO 4 3− , NO 3 , NO 2 , I, F, and SO 3 2− ) was studied at their maximum admissible concentrations in fresh water. The method was applied to fresh-water samples from the Quetta Valley, and the results obtained (0.04 ± 0.001–0.11 ± 0.01 mg/L Fe(II)) were in reasonable agreement with those obtained using the spectrophotometric reference method (0.05 ± 0.01–0.12 ± 0.02 mg/L Fe(II)). The text was submitted by the authors in English.  相似文献   

14.
Microencapsulated n-octadecane with melamine–formaldehyde resin (MF) shell was synthesized by in situ polymerization. Ammonium chloride was used to reduce the residual formaldehyde content of microencapsulated phase change materials (microPCMs) caused by the inherent characteristics of MF. Moreover, microPCMs were heat-treated at 160 °C for 30 min. The surface morphology of the microPCMs fabricated at various microencapsulation periods was examined, and the shell thickness was measured. The effects of heat treatment on the surface morphology, residual formaldehyde content, phase change properties, and thermal stability of the microcapsules were systematically investigated. The globular surface of microcapsules fabricated at microencapsulation period of 120 min was smooth and compact with an average diameter about 2.2 μm, and the shell thickness was ranged from 30 to 70 nm. The thermal stability of heat-treated microcapsules enhanced significantly as microencapsulation period increased; in addition, the residual formaldehyde content of microcapsules decreased from 125 ± 1 mg/kg to 19 ± 1 mg/kg.  相似文献   

15.
A method for the determination of imidacloprid in paddy water and soil was developed using liquid chromatography electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). Separation of imidacloprid was carried out on a Shimadzu C18 column (150 mm × 4.6 mm, 4.6 μm) with an acetonitrile-water (50: 50, v/v) mobile phase containing 0.1% of acetic acid. The flow rate was 0.3 mL/min in isocratic mode. The product ion at 209 m/z was selected for quantification in multiple-reaction monitoring scan mode. Imidacloprid residues in soil were extracted by a solid-liquid extraction method with acetonitrile. Water samples were filtered and directly injected for analysis without extraction. Detection limits of 0.5 μg/kg and 0.3 μg/L were achieved for soil and water samples, respectively. The method had recoveries of 90 ± 2% (n = 4) for soil samples and 100 ± 2% (n = 4) for water samples. A linear relationship was observed throughout the investigated range of concentrations (1–200 μg/L), with the correlation coefficients ranging from 0.999 to 1.000.  相似文献   

16.
As part of a search for environmentally friendly metal chelating ligands, the stability constants of N, N′-ethylenedi-L-cysteine (EC) complexes with Ca(II), Cu(II), Mg(II) and Mn(II) were determined by potentiometry with a glass electrode in aqueous solutions containing 0.1 mol⋅L−1 KCl at 25 °C. Final models are proposed. For the Ca(II)–EC system, the overall stability constants are log 10 β CaHL=14.53±0.03, log 10 β CaL=4.79±0.01 and log 10 β CaL2=8.38±0.04. For the M(II)–EC systems, where M=Cu(II) or Mg(II), the overall stability constants are log10 β CuHL=31.19±0.02 and log 10 β CuL=27.02±0.06 for Cu(II), and are log 10 β MgHL=14.84±0.02 and log 10 β MgL=6.164±0.008 for Mg(II). For the Mn(II)–EC system, the overall stability constant is log 10 β MnL=10.12±0.01. Metal–chelate speciations simulations showed that EC is an efficient chelating agent for Cd(II), Co(II), Cu(II), Ni(II), Pb(II) and Zn(II) for pH≥7.  相似文献   

17.
Metallic elements such as Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Rb, Sr, and Zn were determined using ICP-OES in a representative set of fifteen fruiting bodies of the edible fungus Suillus variegatus. Fruiting bodies were collected from unpolluted areas near the village of Lubichowo of the Bory Tucholskie forest complex in northern Poland in 2007?C2008. The caps were richer in Ag, Al, Cd, Cr, Cu, Fe, K,Mg, Ni, Rb, and Zn, and the stipes in Ba, Ca, Mn, Na, Pb, and Sr. Cobalt concentration in the caps and stipes was similar. In the caps, the content of the elements decreased in the order (mg per kg of dry weight): K 29000 ± 3700, Fe 1600 ± 80, Mg 990 ± 110, Rb 320 ± 86, Zn 90 ± 19, Ca 75 ± 34, Al 68 ± 32, Na 40 ± 18, Cu 19 ± 7, Mn 13 ± 7, Cd 1.0 ± 0.5, Ni 0.64 ± 0.32, Ag 0.40 ± 0.20, Cr 0.33 ± 0.06, Pb 0.20 ± 0.17, Ba 0.19 ± 0.11, Sr 0.15 ± 0.09, and Co 0.070 ± 0.050. Apparently, S. variegatus collected from background areas are relatively low in Pb and Cd and so are suitable for human consumption.  相似文献   

18.
Serotonin (5-hydroxytryptamine, 5-HT) plays vital roles in regulating gastrointestinal functions. Thus, the detection of 5-HT in the gastrointestinal tract is of great importance for biomedical research, medical diagnosis, and pharmaceutical therapy. This paper presents a simple, sensitive, and fast method for the quantification of luminally released serotonin in the feces and tissues of the rat proximal colon by means of capillary electrophoresis with laser-induced fluorescence detection. 5-Carboxyfluorescein N-succinimidyl ester was used for precolumn derivatization of serotonin. The optimal separation and detection conditions were obtained with an electrophoretic buffer containing 60 mM borate (pH 8.90) and an air-cooled argon-ion laser (excitation at 488 nm, emission at 520 nm). The serotonin concentrations in the feces and tissues of proximal colons were analyzed with this method, and the average values of serotonin in the feces samples were 1.951 ± 0.446 ng/mg (male) and 2.095 ± 0.533 ng/mg (female) and 1.397 ± 0.267 ng/mg in rat proximal colon tissues. The results demonstrate that this method can accurately determine luminally released 5-HT in rats.  相似文献   

19.
Four plant parts (leaves, roots, fruits and seeds) of twenty samples of sixteen antidiabetic herbs including three commercially marketed capsules have been analyzed for 6 minor (Na, K, Ca, Cl, Mg, and P) and 21 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sm, Th, V and Zn) elements by instrumental neutron activation analysis (INAA). Further, Ni, Cd and Pb contents were determined by AAS. Elemental data were validated by simultaneously analyzing reference material (RM), MPH-2 Mixed Polish Herbs. Several elements such as Cr and V (1–2 μg/g), Rb (10–40 μg/g), Cs (80–300 ng/g), Se (∼100 ng/g) and Zn (25–60 μg/g) play an important role in diabetes mellitus. Interelemental linear correlations have been observed for Cu vs. Zn (r = 0.89) and Rb vs. Cs (r = 0.87). K/P ratio varies in a narrow range with a mean value of 6.2 ± 1.4. Toxic elements As and Hg were found in <1 μg/g whereas Cd and Pb were in ∼5 μg/g and <10 μg/g, respectively.  相似文献   

20.
The method of diffuse refection has been used for the investigation of complexation reactions between Mg, Ca, Sr, and Ba ions (2+) with bisazosubstituted chromotropic acid derivatives after their sorption on a solid phase. Different adsorbents and methods of the immobilization of metal ions and organic reagent have been tested. The influence of pH on the sorption and subsequent reaction between alkaline-earth metals and organic reagents has been studied. The dependence of analytical signals on the reagent nature has been discussed. Systems have been proposed for the determination of the total concentration of Ca, Sr, and Ba and also Sr and Ba in the concentration range n × 10−4 M; these systems include the sorption of elements on the solid phase of polyacrylonitrile fiber loaded with the Chelex-100 ion exchanger from the solution with pH 7.0 ± 0.5, subsequent treatment of discs with the solutions of Carboxynitrazo or Ortanyl B and the measurement of the coefficients of diffuse refection.  相似文献   

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