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1.
A novel low-energy collective mode of electrons near the Fermi energy has been detected at 5 meV for (9?×?9)-Ag/Cu(111) by high-resolution electron energy loss spectroscopy. This collective electronic excitation does not exist on the bare Cu substrate or on a silver monolayer deposited on Ni(111). It has been assigned to the excitation of the Friedel oscillations in the silver adlayer. Such finding is important for understanding dynamic electron screening at a metal/metal interface. In particular, this work provides the grounds for more accurate theoretical studies aimed at describing the surface loss function and low-energy collective electronic modes in Ag/Cu(111).  相似文献   

2.
Sera of 890 healthy Jinan residents were chosen randomly, and the concentrations of serum Zn and Cu were detected by atomic absorption spectrometry. The mean serum Zn and Cu concentrations and Zn/Cu were 1.32 ± 0.49 mg/l, 0.99 ± 0.26 mg/l, and 1.41 ± 0.56, respectively. Significantly higher levels of serum Zn and Zn/Cu but lower serum Cu were found in the men. Descending tendency of serum Zn and Zn/Cu was observed with social-economic status and age but not significant. Alcohol consumption produced higher level of serum Zn and Zn/Cu but lower Cu concentration. Smoking caused significant lower level in serum Cu concentration but no significance in serum Zn and Zn/Cu. Serum Zn and Zn/Cu were normal only when hours of sleep a night were kept within 7–9 h. Higher level of serum Zn and Cu concentrations and Zn/Cu were observed in individuals with regular physical exercise, but still no significant difference existed. No clear relationship between educational levels with serum Zn and Cu concentrations and Zn/Cu was observed.  相似文献   

3.
 Native nitrite reductases (NIRs) containing both type 1 and 2 Cu ions and type 2 Cu-depleted (T2D) NIRs from three denitrifying bacteria (Achromobacter cycloclastes IAM 1013, Alcaligenes xylosoxidans NCIB 11015, and Alcaligenes xylosoxidans GIFU 1051) have been characterized by electronic absorption, circular dichroism, and electron paramagnetic resonance spectra. The characteristic visible absorption spectra of these NIRs are due to the type 1 Cu centers, while the type 2 Cu centers hardly contribute in the same region. The intramolecular electron transfer (ET) process from the type 1 Cu to the type 2 Cu in native NIRs has been observed as the reoxidation of the type 1 Cu(I) center by pulse radiolysis, whereas no type 1 Cu in T2D NIRs exhibits the same reoxidation. The ET process obeys first-order kinetics, and observed rate constants are 1400–1900 s–1 (t1/2 = ca. 0.5 ms) at pH 7.0. In the presence of nitrite, the ET process also obeys first-order kinetics, with rate constants decreased by factors of 1/12–1/2 at the same pH. The redox potential of the type 2 Cu site is estimated to be +0.24 - +0.28 V, close to that of the type 1 Cu site. Nitrate and azide ions bound to the type 2 Cu site change the redox potential. Nitrite also would shift the redox potential of the type 2 Cu by coordination, and hence the intramolecular ET rate constant is decreased. Pulse radiolysis experiments on T2D NIRs in the presence of nitrite demonstrate that the type 1 Cu(I) site is slowly oxidized with a first-order rate constant of 0.03 s–1 at pH 7.0, suggesting that nitrite bound to the protein accepts an electron from the type 1 Cu. This result is in accord with the finding that T2D NIRs show enzymatic activities, although they are lower than those of the native enzymes. Received: 9 July 1996 / Accepted: 30 January 1997  相似文献   

4.
Laparoscopic adjustable gastric banding (LAGB) causes significant weight loss in morbidly obese adults. However, its consequences on nutritional status still remain unclear. There are a few studies determining the nutritional status after LAGB and none have focused on the serum levels of zinc (Zn), copper (Cu), and ceruloplasmin (CP). We aimed to investigate the effects of LAGB surgery on plasma Zn, Cu, and CP levels. Thirty patients with LAGB with morbid obesity were included. Blood samples were collected preooperatively and in the postoperative third month to determine plasma Zn, Cu, and CP levels. The mean preoperative and postoperative body mass indexes (BMI) were 44.9 ± 7.4 kg/m2 and 44.1 ± 6.5 kg/m2, respectively. The mean weight loss was 12.9 ± 3.3 kg at the postoperative third month. The postoperative Zn (500 ± 130 ng/ml), Cu (280 ± 80 ng/ml), and CP (23.9 ± 8.8 mg/dl) values were statistically significantly lower than the preooperative Zn (740 ± 230 ng/ml), Cu (370 ± 80 ng/ml) and CP (33.3 ± 15.7 mg/dl) levels (p < 0.05). Decreases in the plasma levels of Zn, Cu, and CP were seen postoperatively following LAGB surgery. The nutritional status of LAGB-applied patients should be monitored and mineral supplementation may be considered.  相似文献   

5.
We have developed a new method for forming titanium-nitride(TiN)-coated plates using radio-frequency arc spraying (RFAS). A TiN coating formed by RFAS has been used for electrochemical prevention of marine biofouling. X-ray diffraction and X-ray photoelectron spectroscopy indicate that a TiN composite film containing Ti was formed on a polyethylene terephthalate plate surface when Ti was sprayed by RFAS under atmospheric pressure. A cyclic voltammogram (scan rate 20 mV/s) of the TiN formed by RFAS revealed no oxidative and reductive peak currents in the range −0.6 V to 1.2 V against a saturated silver/silver chloride (Ag/AgCl) electrode. When a potential of 1.0 V against Ag/AgCl was applied to the electrode in seawater, no dissolved Ti was detected. Changes in pH and the chlorine concentration were not observed in this range. In all, only 4.5% of the Vibrio alginolyticus cells attached to the electrode survived when a potential of 0.8 V against Ag/AgCl was applied in seawater for 30 min. In field experiments, attachment of the organisms to the TiN electrode was inhibited by applying an alternating potential of 1.0 V and −0.6 V against Ag/AgCl. The TiN film can be formed by RFAS on large and intricately shaped surfaces, and it is a practical electrode for the electrochemical prevention of fouling of various marine structures. Received: 17 April 1998 / Received revision: 5 June 1998 / Accepted: 19 June 1998  相似文献   

6.
Changes in the cupper (Cu) and zinc (Zn) concentrations have been reported previously in idiopathic dilated cardiomyopathy (IDCMP). As a result of controversial results, the aim of this study was to compare the Zn and Cu concentrations and Zn/Cu ratio of IDCMP patients to healthy volunteers. In addition, the correlation of Cu and Zn levels with age has been evaluated. The study population consisted of 18 IDCMP patients and 27 healthy volunteers. IDCMP patients had normal angiography with echocardiography supporting cardiomyopathy without pericardial and valvular diseases. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week ago. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with SPSS 10 software with independent sample t test for comparing the level of Cu and Zn of IDCMP patients with normal subjects and Pearson correlation to determine the correlation between numeric data. P < 0.05 was considered as significant differences. There was a trend for a lower Zn level in IDCMP patients compared to healthy volunteers. (0.97 ± 0.25 mg/l vs. 1.12 ± 0.42 mg/l, respectively). The mean Cu levels of IDCMP and normal subjects were 1.33 ± 0.20 mg/l and 1.31 ± 0.23 mg/l, respectively. There was a significant difference in Zn/Cu ratio among patients based on the NYHA classification of heart failure (P = 0.003). Age was negatively correlated with Zn levels in IDCMP group (P = 0.037) and positively with Cu levels in healthy volunteers (P = 0.012). A lower Zn level in IDCMP patients compared to healthy volunteers and specially a significant difference in Zn/Cu ratio of patients based on their NYHA classification would suggest a critical role of zinc and Cu imbalance in development of IDCMP.  相似文献   

7.
 The electrochemistry of a water-soluble fragment from the CuA domain of Thermus thermophilus cytochrome ba 3 has been investigated. At 25  °C, CuA exhibits a reversible reduction at a pyridine-4-aldehydesemicarbazone-modified gold electrode (0.1 M Tris, pH 8) with E° = 0.24 V vs NHE. Thermodynamic parameters for the [Cu(Cys)2Cu]+/0 electrode reaction were determined by variable-temperature electrochemistry (ΔS°rc = –5.4(12) eu, ΔS° = –21.0(12) eu, ΔH° = –11.9(4) kcal/mol;ΔG° = –5.6 (11) kcal/mol). The relatively small reaction entropy is consistent with a low reorganization energy for [Cu(Cys)2Cu]+/0 electron transfer. An irreversible oxidation of [Cu(Cys)2Cu]+ at 1 V vs NHE confirms that the CuII:CuII state of CuA is significantly destabilized relative to the CuII state of analogous blue-copper proteins. Received: 3 June 1996 / Accepted: 26 August 1996  相似文献   

8.
In 10- to 16-year-old children, inhabitants of industrial towns of Ukraine, an X-ray fluorescence analysis of the content of some chemical elements in hair samples allowed us to find a deficiency of Zn and Cu against the background of excesses of Ca, Cr, Ni, Mo, and Cd. Comparison of the parameters of EEG frequency components and levels of Ca, Zn, Cu, Fe, Mn, Co, Cr, Mo, Ni, Sr, Pb, and Cd showed that there are significant correlations between the normalized values of spectral powers of many frequency components of the ongoing EEG recorded in different functional states (eyes closed/open, solving an arithmetic task, and phono-/photostimulation) and concentrations of ten of the above-mentioned trace elements. Comparative estimation of the neurotropicity of the elements showed the following sequence of numbers of significant correlations (shown in parentheses) from the total set of possible comparisons: Cd (35) > Ni (31) > Cr (19) > Sr (17) > Pb (16) > > Ca (10) > Cu (7) > Mo (3) > Zn (2) > Fe (1). The intensity of correlations (values of the correlation coefficients) varied from 0.26 to 0.42 at 0.05 < P < 0.001; more frequently, such correlations were observed under conditions of EEG recording with the eyes closed (39) and upon solving an arithmetic task (33).  相似文献   

9.
Deficiencies in Cu, Se, and Zn impair one or more biochemical functions, and excess are associated with toxicity. Baseline studies on the Ghanaian population are scanty. The study was undertaken to determine whether significant rural/urban differences in the serum levels of Cu, Se, and Zn did exist. Forty males/60 females from rural and 50 males/50 females from urban Ghanaian communities were sampled. Serum Cu, Se, and Zn were determined using flame atomic absorption spectrometry. Cu level for rural and urban subjects was 997 ± 333 and 979 ± 290 μg/L, respectively (p = 0.68). However, Cu levels were significantly higher in the rural females (1,063 ± 367 μg/L) than the rural males (898 ± 249 μg/L; p = 0.0085). Se levels for rural/urban subjects were 97 ± 36 and 87 ± 31 μg/L, respectively (p = 0.03). Zn levels in the rural/urban subjects were 312 ± 218 and 150 ± 102 μg/L, respectively (p = 0.002). Additionally, Zn was significantly higher in rural females (428 ± 204 μg/L) than the urban females (166 ± 103 μg/L; p = 0.0002). Finally, Zn was significantly higher in rural females (428 ± 204 μg/L) than males (172 ± 116 μg/L; p = 0.0028). In conclusion, Cu, Se, and Zn were higher in the rural group compared to the urban group, and the generally low Zn levels were confirmed in another cohort follow-up study.  相似文献   

10.
Ethambutol is an oral anti-tuberculosis agent with chelating effects owing to its chemical structure which is similar to that of penicillamine. Copper (Cu) is an essential trace element that has important roles in physiological function of the body organs. The aim of present study was to determine (1) whether ethambutol usage can alter serum Cu concentration in patients with tuberculosis and (2) whether there is any relationship between age, sex, and smoking habit of patients with changes in serum Cu levels. Sixty patients with diagnosis of pulmonary tuberculosis were enrolled the study. Blood samples were obtained before treatment (baseline) and 10 days after starting anti-tuberculosis therapy. The amounts of serum Cu were determined in all samples by atomic absorption. Mean ± SD levels of Cu at baseline and on the 10th day of ethambutol use were 0.94 ± 0.24 and 0.64 ± 0.24 μg/mL, respectively. Statistical analysis confirmed a significant difference (p < 0.0001). Also, there was not any relationship between changes in Cu concentration and study variables of age, sex, and smoking habit. Our findings endorse the chelating effect of ethambutol leading to a decrease in serum levels of cationic trace elements, e.g., Cu.  相似文献   

11.
The aim of this study was to investigate the respiratory function disorders that could be related to dust exposure during the production of copper mine in copper mineworkers (CMWs). The study included 75 male CMWs (mean age, 32.0 ± 7.1 years, 58.6% smokers) and 75 male age- and smoking status-matched healthy control subjects. Serum Cu level was significantly higher in the CMW group (0.80 ± 0.62 μg/ml) than the control group (0.60 ± 0.39 μg/ml) (p = 0.017). Significant negative correlations were found between serum Cu level and forced expiratory volume in first second (r = −0.600; p < 0.001) and between serum Cu level and forced vital capacity (r = −0.593; p = <0.001) in CMWs. Serum Cu level was significantly higher in the restrictive type pulmonary function disorders group (1.36 ± 0.62 μg/ml) than obstructive type (0.90 ± 0.55 μg/ml) and normal pulmonary function pattern group (0.53 ± 0.43 μg/ml) (p < 0.001). Patients with radiological parenchymal abnormalities had significantly higher serum copper levels than those without abnormalities (1.53 ± 0.52 vs. 0.71 ± 0.52 μg/ml, respectively; p = 0.002). In conclusion, result of the study has shown a negative association between pulmonary functions disorders and radiological abnormalities and serum Cu levels in CMWs.  相似文献   

12.
Copper (Cu) is an integral part of many important enzymes involved in a number of vital biological processes. Even though Cu is essential to life, it can become toxic to cells, at elevated tissue concentrations. Oxidative damage due to Cu has been reported in recent studies in various tissues. In this study, we aimed to determine the effect of excess Cu on oxidative and anti-oxidative substances in brain tissue in a rat model. Sixteen male Wistar albino rats were divided into two groups: the control group, which was given normal tap water, and the experimental group, which received water containing Cu in a dose of 1 g/l. All rats were sacrificed at the end of 4 wk, under ether anesthesia. Cu concentration in the liver and in plasma alanine aminotransferase (ALT) and aspartate transaminase (AST) activities were determined. There were multiparameter changes with significant ALT and AST activity elevation and increased liver Cu concentration. In brain tissue, Cu concentration, superoxide dismutase (SOD) activities, malondialdehyde (MDA) levels and glutathione (GSH) concentrations were determined. Brain Cu concentration was significantly higher in rats receiving excess Cu, compared with control rats (p < 0.05). Our results showed that SOD activities and GSH levels in brain tissue of the Cu-intoxicated animals were significantly lower than in the control group (p < 0.01 and p < 0,001, respectively). The brain MDA levels were found to be significantly higher in the experimental group than in the control group (p < 0.001). The present results indicate that excessive Cu accumulation in the brain depressed SOD activities and GSH levels and resulted in high MDA levels in brain homogenate due to the lipid peroxidation induced by the Cu overload.  相似文献   

13.
Water dispersible zinc sulfide quantum dots (ZnS QDs) with an average diameter of 2.9 nm were synthesized in an environment friendly method using chitosan as stabilizing agent. These nanocrystals displayed characteristic absorption and emission spectra having an absorbance edge at 300 nm and emission maxima (λ emission) at 427 nm. Citrate-capped silver nanoparticles (Ag NPs) of ca. 37-nm diameter were prepared by modified Turkevich process. The fluorescence of ZnS QDs was significantly quenched in presence of Ag NPs in a concentration-dependent manner with K sv value of 9 × 109 M−1. The quenching mechanism was analyzed using Stern–Volmer plot which indicated mixed nature of quenching. Static mechanism was evident from the formation of electrostatic complex between positively charged ZnS QDs and negatively charged Ag NPs as confirmed by absorbance study. Due to excellent overlap between ZnS QDs emission and surface plasmon resonance band of Ag NPs, the role of energy transfer process as an additional quenching mechanism was investigated by time-resolved fluorescence measurements. Time-correlated single-photon counting study demonstrated decrease in average lifetime of ZnS QDs fluorescence in presence of Ag NPs. The corresponding F?rster distance for the present QD–NP pair was calculated to be 18.4 nm.  相似文献   

14.
Changes in the copper (Cu) and zinc (Zn) concentrations have been reported previously in ischemic cardiomyopathy (ISCMP). Due to controversial results, the aims of this study were to compare levels of Cu, Zn, and Zn/Cu ratio of ISCMP patients with healthy volunteers and also to investigate the possible relationship between trace elements status in ISCMP patients with the severity of clinical disease based on the New York Heart Association (NYHA) classification. The subjects of this study consisted of 30 ISCMP and 27 healthy volunteers. ISCMP was diagnosed with a history of previous myocardial infarction and also coronary artery disease was confirmed by coronary angiography. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with the SPSS 10 software using independent sample t test for comparing the levels of Cu and Zn between ISCMP and normal subjects. The mean Cu level of the ISCMP group (1.54 ± 0.52 mg/L) was significantly more than the Cu levels of the healthy volunteers (1.31 ± 0.24 mg/L; p = 0.048). The mean Zn levels of the ISCMP and healthy volunteers were 1.05 ± 0.28 and 1.12 ± 0.42, respectively, without any significant difference between groups. There was a trend for higher Cu level, lower Zn level, and lower Zn/Cu ratio in NYHA III patients in comparison with NYHA II group. Considering the results of this study, Cu may have a role in the development of ISCMP. Interventions such as administration of Cu chelators to relieve the symptoms or to decrease the progression of ISCMP is needed to be examined in large clinical trials. In this study, the Zn level of ISCMP patients was not significantly different in comparison with the healthy volunteers.  相似文献   

15.
Determination of copper in human tissues and body fluids may be crucial in the diagnosis of Wilson’s disease. In this study we evaluated urinary copper excretion and urine and blood concentration in 14 patients in whom Wilson’s disease was confirmed (group A) and in 21 subjects in whom the disease was only suspected (group B). The following values (mean ± SD) were found: 24-h urine (μg Cu/24 h), 152 ± 135 (A) and 31.8 ± 10.9 (B); urine (μg Cu/ml), 0.091 ± 0.087 (A) and 0.028 ± 0.011 (B); and blood (μg Cu/ml), 0.62 ± 0.25 (A) and 0.72 ± 0.09 (B). By comparison, urine copper concentration in the group of apparently healthy subjects was 0.035 ± 0.010 (n = 50), and blood copper concentration in autopsy cases of nonpoisoned people was 0.85 ± 0.19 (n = 73).  相似文献   

16.
A 2 × 3 factorial arrangement of treatments was used to investigate the effects of different levels of copper (Cu, 0, 19, and 38 mg/kg, dry matter (DM)) and molybdenum (Mo, 0 and 5 mg/kg, DM) supplements and an interaction of these two factors on growth performance, nutrient digestibility, and cashmere and follicle characteristics in cashmere goats. Thirty-six Liaoning cashmere goats (approximately 1.5 years of age; 27.53 ± 1.38 kg of body weight) were assigned randomly to one of six treatments and fed with Chinese wildrye- and alfalfa hay-based treatment diets (the basal diet contained 4.72 mg Cu/kg, 1.65 mg Mo/kg, and 0.21% S.). Body weight was measured on two consecutive days at the start and the end of the 70-day experimental period. On day 30, the metabolism trial was conducted to study the effects of dietary Cu and Mo on nutrient digestibility. The cashmere and skin samples were collected on day 70. Copper supplementation increased (P < 0.05) growth performance and fiber digestion, but there were no differences (P > 0.05) between Cu-supplemented groups. Addition of 19 mg Cu/kg DM increased (P < 0.05) cashmere growth length or growth rate by increasing the number of active secondary follicles. Molybdenum supplementation decreased (P < 0.05) growth, but did not affect (P > 0.05) nutrient digestion, cashmere, and follicle characteristics. There is a tendency or significant interaction effect of Cu and Mo on growth performance (P = 0.057), cashmere growth (P = 0.076), or diameter (P < 0.05) which might be accomplished by changing the number of secondary follicle and active secondary follicle, and secondary to primary follicle ratio. In conclusion, the optimal supplemental Cu level for Liaoning cashmere goats fed with the basal diet was 19 mg/kg DM (the total dietary Cu level of 23.72 mg/kg DM), while 38 mg Cu/kg DM supplementation was found to be needed when 5 mg Mo/kg was added in the basal diet during the cashmere growing period.  相似文献   

17.
Variations of copper (Cu) concentration and ceruloplasmin (Cp) activity in serum and plasma of dairy cows at different stages of lactation were assessed in 240 Holstein dairy cows. Furthermore, ceruloplasmin to copper ratios were also investigated. The cows were classified according to their lactation stages into four different groups as close-up stage (3–1 week(s) antepartum), fresh lactation stage (0–1 week postpartum), early lactation stage (3–5 weeks postpartum), and mid-lactation stage (15–18 weeks postpartum). Each group consisted of 60 multiparous cows. Serum and heparinised plasma samples were obtained from each cow. Concentrations of serum copper (sCu) and plasma copper (pCu) as well as activities of plasma Cp (pCp) were higher in the group of fresh lactation stage than other groups (P < 0.05). Serum Cp (sCp) exhibited no significant difference between fresh lactation and early lactation groups (P > 0.05). Low correlations were obtained between sCp and pCu, sCp and sCu, and sCu and pCu. Plasma copper concentration and plasma ceruloplasmin activity were higher than serum copper concentration and serum ceruloplasmin activity, respectively (P < 0.001). The ratios of Cp activity to Cu concentration (Cp/Cu) were not significantly changed in the different lactation stages of dairy cows (P > 0.05). Use of sCp/pCu and sCp/sCu rather than pCp/pCu will reduce the calculated value of Cp/Cu. Furthermore, for evaluation of copper status, use of sCp/sCu or sCp/pCu identified more animals as ‘low’ and ‘marginal’ than using pCp/pCu (P < 0.001). It can be concluded that ceruloplasmin and copper undergo a physiological increase just after calving; thus, their values should be interpreted with caution during assessment of copper status. Plasma measurements should be used for calculation of Cp/Cu, and further research is required to refine diagnosis criteria for use of such ratio in determining copper status in dairy cows.  相似文献   

18.
The aim of this study is to determine the content of total iron (TFe), heme iron (HeFe), zinc (Zn), and copper (Cu) in different cuts of meat and viscera from rabbit. Five young New Zealand rabbits were used in the study. Samples in triplicate were obtained from three meat cuts (foreleg, hind leg, and loin) and from main viscera. TFe, Zn, and Cu concentrations from samples were determined by wet acid digestion followed by atomic absorption spectrophotometry (AAS), while HeFe was determined by acid extraction followed by AAS. Mean TFe, HeFe, Zn, and Cu in meat was 0.83 ± 0.09, 0.56 ± 0.11, 0.95 ± 0.35, and 0.08 ± 0.01 mg/100 g, respectively. TFe content was less than 1 mg/100 g in all meat cuts. Sixty-seven percent of iron content was HeFe. The cut of meat with highest Zn concentrations was the foreleg with 1.33 ± 0.12 mg/100 g. Cu content was low for all meat cuts. TFe, HeFe, Zn, and Cu content in viscera varied greatly. The spleen was the organ with the highest TFe and Zn concentrations (82.79 ± 9.22 mg/100 g and 3.49 ± 0.63 mg/100 g, respectively). Nevertheless, the lungs had the highest concentration of HeFe (5.79 ± 0.90 mg/100 g), accounting for 91% of the total iron. The liver had the highest Cu content (3.89 ± 0.89 mg/100 g). Rabbit meat has low TFe concentration, similar to that of poultry, and most of the iron is HeFe. The amount of minerals in viscera closely depends on their function.  相似文献   

19.
Five brands of antidiabetic herbal formulations as tablets, Diabetex, Divya Madhu Nashini, Jambrushila, Diabeticin, and Madhumeh Nashini, from different pharmacies were analyzed for six minor (Na, K, Ca, Cl, Mg, and P) and 20 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sm, Th, V, and Zn) elements by thermal neutron irradiation followed by high-resolution gamma ray spectrometry. Further Ni, Cd, and Pb were determined by atomic absorption spectrophotometry. Most elements vary in a narrow range by a factor of 2–4 while a few others vary in a wide range, e.g., Na (0.05–0.67 mg/g), Mn (26.7–250 μg/g), and V (0.26–2.50 μg/g). All the five brands contain K, Cl, Mg, P, and Ca as minor constituents along with mean trace amounts of Cr (2.11 ± 0.67 μg/g), Cu (15.7 ± 7.11 μg/g), Fe (459 ± 171 μg/g), Mn (143 ± 23 μg/g), Se (238 ± 112 ng/g), and V (0.99 ± 0.93 μg/g). Jambrushila is enriched in Na, Ca, Mg, Cl, Fe, Cu, Se, and Zn, essential nutrients responsible for curing diabetes. Dietary intake of Mn, Fe, and Cu are greater than 10% of the recommended dietary allowance, whereas that for Zn and Se is less than 2%. Mean contents of toxic elements (As, Cd, Hg, and Pb) were found below permissible limits except in Jambrushila. Cr and Zn were inversely correlated with r = −0.81, whereas Rb and Cs exhibit linear correlation (r = 0.93) in five brands. C, H, N analysis showed C ∼ 55%, H ∼ 12%, and N ∼ 2% with a total of ∼70% organic matter. However, thermal decomposition studies at 700°C suggest less than 5% nonvolatile metal oxides. Herbal formulations contain minor and trace elements in bioavailable forms that favorably influence glucose tolerance and possibly increase the body’s ability to ameliorate development of diabetes.  相似文献   

20.
With the help of quantum mechanical calculations, we have examined the series of central system X(ML)3 +(X = O, S, Se; M = Au, Ag, Cu). Using a scalar–relativistic density functional approach, we studied the geometry structures, Mulliken populations and charges of the systems. Structure parameters of the experimental systems are reproduced well with Xα method. The metallophilic interaction energy is analyzed and decomposed. For the systems with different central atoms and different metal atoms, the nature of the metallophilic attraction interaction is analyzed.  相似文献   

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