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1.
Concentrations of copper and zinc in plasma, whole blood, and erythrocytes were determined in pulmonary tuberculosis (TB) patients and controls by atomic absorption spectrophotometry. The plasma and whole blood copper/zinc ratios were markedly higher in the TB patients. Eighty-seven percent of the TB patients had plasma copper/zinc ratios above 2.00, and 94% had whole blood copper/zinc ratios above 0.20. None of the controls had plasma copper/zinc ratios above 2.00, while 24% of the controls had whole blood ratios greater than 0.20. Whole blood and plasma copper/zinc ratios appear to be more sensitive indicators of the presence of pulmonary TB than the individual copper and zinc concentrations. Patients with conditions in which copper and zinc metabolism are altered might benefit from the monitoring of copper/zinc ratios.  相似文献   

2.
血清铜锌硒与卵巢癌关系的研究   总被引:2,自引:1,他引:1  
对 40例卵巢癌患者进行血清铜、锌、硒及铜 /锌比值测定 ,并以 48例健康成年女性为对照。测定结果进行单因素分析和非条件 Logistic多因素分析。单因素分析结果表明 ,卵巢癌患者血清锌、硒低于正常组 ,铜 /锌比值升高 ,而血清铜无显著差异 ;有负荷患者铜 /锌比值明显高于无负荷患者 ,而血清锌、硒无显著差异。回归多因素分析表明 ,硒、锌是卵巢癌发病的保护因素 ,揭示锌、硒在卵巢癌预防及辅助治疗上均有一定价值。  相似文献   

3.
The kinetics of serosal copper transfer and the distribution of copper between metallothionein (MT) and a high-molecular-weight protein fraction (HMWPF) within the mucosal cells were examined, using isolated duodenal segments from rats fed different amounts of zinc. No difference in the Vmax or Km for serosal transfer could be detected between the different zinc groups, suggesting that zinc did not affect this aspect of copper absorption. When intestinal segments from rats fed the low zinc diet were incubated in high copper media, the majority of the copper was associated with the HMWPF, while those from rats fed the high zinc diet had the largest proportion bound to MT. All the intestines incubated in the low copper media, regardless of rat zinc status, had the majority of copper associated with MT. These results suggested that with the low zinc diet, the limited amount of MT present was saturated, and the excess copper was bound to the HMWPF. With larger intakes of zinc, MT synthesis was induced, and the larger amount of this protein was not as readily saturated, resulting in less copper binding to the HMWPF and more to MT. It is suggested that zinc interferes with copper absorption by inducing MT, which sequesters copper in the mucosal cells, making it unavailable for serosal transfer. The copper bound to the HMWPF is available for transfer.  相似文献   

4.
Copper and zinc absorption in the rat: mechanism of mutual antagonism   总被引:6,自引:0,他引:6  
The influence that copper and zinc exert on each other's absorption was studied by using the isolated, vascularly perfused rat-intestine system. In the first series of experiments, rats were fed for 1 wk one of nine diets, with different copper and zinc concentrations representing low, adequate and high dietary metal intakes. Copper concentrations were 1, 6 and 36 mg/kg diet and zinc concentrations were 5, 30 and 180 mg/kg. The small intestine was perfused with M199 tissue culture medium containing 6 mg/L copper and 30 mg/L zinc. Neither metal was found to significantly alter the other's absorption. High dietary zinc increased metallothionein-bound copper but did not change the intracellular copper concentration. In the second series of experiments, the dietary copper and zinc concentrations were held at 6 mg/kg and 30 mg/kg, respectively, while the metal concentrations in the luminal perfusate were changed (from 1 to 36 mg/L and from 5 to 180 mg/L for copper and zinc, respectively). The higher copper concentrations in the perfusate increased zinc accumulation in mucosal cells and decreased the zinc transferred to the portal perfusate at the highest luminal zinc concentration. These data indicate that a competition and/or inhibition of a pathway for zinc out of the mucosal cell occurs at high luminal copper concentrations. High luminal zinc concentrations in the perfusate decreased the copper concentration in the mucosal cell cytosol and the amount transferred to the portal effluent. These results taken together indicate that a competition and/or inhibition of copper or zinc intake into intestinal cells occurs when the luminal concentration of the respective congener is very high.  相似文献   

5.
Effect of zinc intake on copper excretion and retention in men   总被引:2,自引:0,他引:2  
To determine the influence of zinc intake on copper excretion and retention, nine men consumed diets containing 2.6 mg of copper/day and 1.8, 4.0, 6.0, 8.0, 18.5 or 20.7 mg of zinc/day for one- or two-week periods in a 63-day study. Copper and zinc in the diet and copper in plasma were determined weekly; fecal copper was determined daily and averaged within each week. The weekly mean (+/-SEM) plasma copper concentrations (81 +/- 3.3 to 100 +/- 5.8 micrograms/dl) remained within the normal range throughout the study. Fecal copper and apparent copper retention were influenced by the level of dietary zinc and the duration it was fed. When 18.5 mg of zinc/day was fed for two consecutive weeks following a lower zinc intake, fecal copper was elevated and apparent copper retention was reduced after a one-week lag. Thus, an intake of zinc only 3.5 mg/day above the RDA for men reduced apparent retention of copper at an intake of 2.6 mg/day.  相似文献   

6.
A prospective study of zinc and copper replacement concurrently with total parenteral nutrition was undertaken during 29 courses of total parenteral nutrition in 20 tumor-bearing patients. Urinary excretion of zinc and copper was prospectively studied in eight of these subjects. While progressive declines in zinc and copper blood levels occurred in four unsupplemented control patients, maintenance of plasma trace metal concentrations within normal limits was accomplished by daily intravenous zinc and copper. A daily intravenous intake of 70 to 80 micrograms/kg of zinc and 60 to 65 micrograms/kg of copper were generally associated with normal blood levels and positive urinary balance of these trace elements. This study outlines a safe and effective zinc and copper replacement regimen in patients undergoing total parenteral nutrition.  相似文献   

7.
Analyses for zinc and copper were performed in samples of serum, hair, toenails, and a 24-hr urine from Polynesian men and women resident in the Tokelau Islands. Selection of subjects was according to rank of systolic blood pressure obtained in a previous survey. The only difference in zinc anc copper values between the men and the women was a higher hair zinc concentration observed for the men. Rank of blood pressure had no influence on the measurements for zinc or copper, although within blood pressure ranks the men again had a higher hair zinc concentration than the women. Analysis of Tokelauan foods showed that most contained very low concentrations of zinc anc also low concentrations of copper. Octopus was one of the few rich sources of zinc and copper. Estimated daily dietary intakes (excluding water) were 4.5 mg Zn and 1.5 mg Cu. The reliability of measurements in serum, urine, hair, and toenails for assessing zinc and copper status is questioned.  相似文献   

8.
We examined interaction of the trace element zinc with copper and lead. In sickle cell anemia, the usual situation is one of mild to moderate zinc deficiency owing to renal loss of zinc. Zinc deficiency seems to produce a mild overburden of copper and an increased ceruloplasmin level, probably by enhancing copper absorption. With zinc therapy, this process is reversed. Pharmacological doses of zinc, when administered in a way to ensure effectiveness (without food) will usually lead to copper deficiency. We have taken advantage of the copper-depleting effect of zinc to design a new therapy for Wilson's disease. Zinc, by inducing intestinal metallothionein, inhibits absorption of copper from food, and inhibits reabsorption of endogenously secreted copper, thereby producing a negative copper balance in Wilson's disease. Once we are certain that zinc blocks accumulation of copper in the liver of Wilson's disease patients, zinc therapy will be available as one approach for treating this fatal disease. The animal literature indicates that zinc protects against lead toxicity when both elements are given orally, no doubt through the intestinal metallothionein mechanism. In preliminary experiments in rats, we have not been able to show that toxicity from lead that arrives into the body through a nonoral route is affected by oral zinc supplements.  相似文献   

9.
正常情况下,人体含有一定量的锌、铜微量元素。血液中极少量的锌、铜对血脂代谢的稳定有一定影响,锌、铜微量元素的缺乏或过量都有可能导致血脂代谢紊乱。从膳食中合理摄取锌、铜对血脂代谢有着非常重要的意义。  相似文献   

10.
The effect of humic acids (HAs) on the toxicity of copper, zinc, and lead was investigated using the photobacterium Vibrio fischeri (Microtox test) as a test organism. The effects of HAs on metal toxicity were evaluated as functions of time and concentration in pure compound solutions. The toxicities of copper and lead were generally comparable, while the toxicity of zinc was lower than those of the other two metals. The toxicity of copper decreased with the addition of HAs, while the toxicity of zinc remained almost constant. On the other hand, the toxicity of lead increased, depending on the concentration of HAs. The interactive effects between copper and zinc and between lead and zinc were synergistic, while the interactive effect between copper and lead on the bioluminescence of V. fischeri was additive. The presence of HAs caused relatively high toxicity reduction in the binary mixtures of zinc and copper or zinc and lead, while the toxicity reduction in the case of the binary mixture of copper and lead was negligible.  相似文献   

11.
The effects of zinc, copper, and selenium on human congenital heart defects (CHDs) remain unclear. This study aimed to investigate the associations of the maternal total, dietary, and supplemental intakes of zinc, copper, and selenium during pregnancy with CHDs. A hospital-based case-control study was performed, including 474 cases and 948 controls in Northwest China. Eligible participants waiting for delivery were interviewed to report their diets and characteristics in pregnancy. Mixed logistic regression was adopted to examine associations and interactions between maternal intakes and CHDs. Higher total intakes of zinc, selenium, zinc to copper ratio, and selenium to copper ratio during pregnancy were associated with lower risks of total CHDs and the subtypes, and the tests for trend were significant (all p < 0.05). The significantly inverse associations with CHDs were also observed for dietary intakes of zinc, selenium, zinc to copper ratio, selenium to copper ratio, and zinc and selenium supplements use during pregnancy and in the first trimester. Moreover, high zinc and high selenium, even with low or high copper, showed a significantly reduced risk of total CHDs. Efforts to promote zinc and selenium intakes during pregnancy need to be strengthened to reduce the incidence of CHDs in the Chinese population.  相似文献   

12.
目的 了解云南大红山铜矿成年居民铜、铁、锌的血清水平和膳食摄入量.方法 在大红山矿区随机抽取180名成年居民,采用原子吸收分光光度法检测血清铜、铁、锌水平.从180人中随机抽取60人,采刚化学分析法调查膳食铜、铁、锌摄入量.结果 171人的血清铜、铁、锌水平分别为(0.90±0.18)、(1.25±0.93)、(0.75±0.28)mg/L,血清铜和铁呈显著负相关(r=-0.26,P<0.001).血清铜与年龄呈显著正相关(r=0.25,P<0.001),女性血清铜水平明显高于男性(P=0.011).60人的膳食铜、铁、锌摄入量分别为(1.74±1.09)、(16.29±10.73)、(7.56±3.38)mg/d,女性均明显低于男性(P<0.05).血清铜、铁、锌水平和膳食摄入量均存在地区差异.结论 云南大红山矿区成年居民血清铜、铁水平均正常,血清锌水平偏低.铜、铁、锌的膳食摄入量均未超过可耐受最高摄人量,且部分人摄入量偏低.  相似文献   

13.
《Nutrition Research》1986,6(4):451-457
Short term, severe dietary zinc and copper deficiencies have been produced in young rats. Copper deficiency significantly depresses erythrocyte copper, 1.4 vs 3.4 μg/g protein, but does not affect erythrocyte membrane copper concentration. However, copper deficiency causes a significant increase in erythrocyte membrane zinc, 78 vs 60 μg/g protein. Dietary zinc deficiency causes a depression in erythrocyte membrane zinc, 41 vs 61 μg/g protein.  相似文献   

14.
Twelve carbohydrate-sensitive and 12 non-carbohydrate sensitive (normal) men were studied. Carbohydrate sensitivity was identified by hyperinsulinemic and normoglycemic responses to a sucrose load. In a blocked split-plot design, fasted subjects were given 2 g/kg body weight of sucrose or invert sugar, and responses of plasma zinc, copper, insulin, and glucose were determined. Erythrocyte zinc and copper also were measured. Blood samples were taken 0, 0.5, 1, 2, and 3 hours after the sugar loads were given. Plasma zinc, copper, insulin, and glucose did not differ significantly between the two sugar loads. Neither did erythrocyte zinc and copper differ significantly between the two load doses. Also, plasma zinc, copper, and glucose, as well as erythrocyte zinc and copper, did not differ significantly between the carbohydrate-sensitive and normal men. Plasma insulin was significantly higher in the carbohydrate-sensitive than the normal men. Plasma zinc did not change significantly between sampling times. Plasma copper declined progressively over the testing period. The greater the elevation of plasma glucose above the fasting level, the greater the plasma copper was depressed. Copper appears to be withdrawn from plasma after sugar loading to facilitate glucose uptake and metabolism.  相似文献   

15.
孕妇锌 铜 钙 磷营养状况对新生儿的影响   总被引:3,自引:0,他引:3  
目的 :观察孕妇锌、铜、钙、磷营养状况对新生儿的影响。方法 :测定未孕妇女及孕妇血清和新生儿脐血锌、铜、钙、磷水平 ,并对孕妇进行膳食调查。结果 :孕期血清锌有下降趋势 ,血清铜、磷显著升高 ,脐血锌、钙高于母血水平 ,铜、磷低于母血水平 ;孕晚期锌与新生儿出生体重呈正相关 ;孕妇膳食中锌、钙摄入量不足。结论 :孕妇锌、铜、钙、磷营养状况对新生儿有一定的影响  相似文献   

16.
《Nutrition Research》1987,7(4):393-399
Abnormal zinc metabolism has been identified in human subjects with non-insulin dependent diabetes mellitus (NIDDM), who are also frequently obese. In this study, we have examined the relative effects of obesity and diabetes on tissue zinc and copper concentrations in several tissues (liver, kidney, testis, muscle, and bone) from control and streptozotocin diabetic lean and obese male Zucker rats. Obese Zucker rats had significantly lower hepatic zinc and copper and higher muscle and femur zinc concentrations than did their lean controls. Diabetic animals had significantly increased hepatic and renal zinc and copper concentrations. Therefore, obesity and diabetes have distinct effects on zinc and copper concentrations in these tissues. The nearly normal zinc and diabetic conditions on hepatic concentrations of these two trace metals.  相似文献   

17.
Few data on the copper and zinc contents of convenience items and frozen foods have been reported in the literature. In this study, selected meats, frozen vegetables, and convenience items were analyzed for copper and zinc content by atomic absorption spectrophotometry. Foods found to have the highest copper content tended to be highest in zinc as well. Beef liver was an outstanding source of both minerals. Protein foods were generally good sources of zinc, supplying more than 2 mg/100-gm serving. Foods containing more than 0.2 mg copper per 100 gm were considered to be good sources. Examples included chicken livers, garbanzo beans, frozen Mexican-style dinner, and frozen brownies. Most of the other foods analyzed contained relatively small amounts of copper and zinc. Nevertheless, the contribution of such foods to the total daily copper and zinc intake illustrates the desirability of including a wide variety of foods in the diet.  相似文献   

18.
Histological changes are shown of ossification induced by a simultaneous exposure to zinc and cadmium or to zinc and copper using embryonic chick femur in a culture system. Cadmium caused an atrophic change of the osseous tissue in the absence of zinc but caused an osteomalacic change with a partial degenerative change in the presence of zinc after a 6-day culture. Copper caused an atrophic change in the absence or presence of zinc. These observations were partly supported by the fact that the diaphysial calcium content was significantly decreased by zinc alone, and the decrease was unaffected by cadmium or copper. Zinc significantly decreased cadmium accumulation but not copper accumulation in the diaphysis. Thus, in spite of the inhibitory effect on calcification, zinc prevented a decrease in bone matrix formation caused by cadmium but not that by copper. Exposure of chick femur culture to zinc and cadmium induced changes consistent with osteomalacia, i.e., decreased mineralization of bone, with or without suppression of matrix formation. Exposure to zinc and copper, however, induced changes consistent with osteoporosis, i.e., decreased mineralization and matrix formation.  相似文献   

19.
通过对32例铅蓄电池制造工和20例正常人对照组的染色体畸变及微量元素铅、铜、锌的研究。发现两组间的染色体畸变率、血铅、血铜、血锌均有高度显著性差异(P<0.01)。并进一步发现接触组的血铅、染色体畸变率、血铜、血锌、锌铜比之间呈不同程度的相关,其中血铅与染色体畸变率有高度显著性正相关(r=0.422,P<0.01),血铅与锌铜比呈高度显著性负相关(r=-0.481,P<0.005)  相似文献   

20.
铁、铜对过量锌饲养小鸡生物效应的影响   总被引:2,自引:0,他引:2  
李劲松  吴训贤 《营养学报》1992,14(3):288-294
本文对饲料中过量锌对小鸡铁,铜利用的影响以及补充适量铜或铁、铜的预防效果进行了研究。一日龄雄性小鸡喂基础饲料5天后按体重分成4组,用铁锌铜含量不同的实验饲料喂养28天,观察小鸡生长情况及血液生化指标。结果表明,高锌组小鸡生长不良,Hb下降13%,RBC,Hct,MCV均降低、FEP增加,呈现典型小细胞低色素贫血态,血液及肝肾中锌含量增加,铁和铜含量减少;红细胞超氧化物岐化酶和血浆铜兰蛋白活性下降。在含锌饲料中补充铜能改善小鸡的生长状况,体内铜水平及铜依赖酶活性,对改善贫血及体内铁水平的作用不明显。同时补铁则小鸡各项实验指标均得到明显改善。  相似文献   

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