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1.
Previous surveys have suggested that preschool children in the North and Northeast of Thailand are at risk of inadequate vitamin A nutriture. Therefore, vitamin A status was assessed in 996 children aged 2-6 years in the North and Northeast Thailand during the dry (Feb.-April) and rainy (Sept.-Nov.) seasons. Approximately 1 per cent of samples during both periods exhibited serum retinol concentrations below 10 mcg/dl with means (+/-SD) concentration of 29 +/- 9.8 mcg/dl in the dry season and 37 +/- 15.4 mcg/dl in the rainy season. About one fifth of the studied children showed abnormal CIC and depleted liver stores (RDR > 20%). High risk areas were ranked and corresponded well by these 2 indicators. Therefore, it is concluded that the magnitude of the problem estimated by RDR and CIC are a more precise measurement of marginal vitamin A status than serum vitamin A level alone and about one-fifth of preschool children in the North and Northeast regions of Thailand experience subclinical vitamin A deficiency.  相似文献   

2.
In the liver of 4 newborns, 2 infants and 2 children the levels of residues of chlorinated hydrocarbons were determined. The highest levels of sigma HCH (817 mcg/kg of fat, 17.1 mcg/kg of tissue) were found in a 2-day-old newborn, the lowest ones (43 mcg/kg of fat, 1.8 mcg/kg of tissue) were in an infant aged 12 months. The content of sigma DDT was highest (3044 mcg/kg of fat, 93.8 mcg/kg of tissue) in the liver of an infant aged 13 days, the lowest values (322 mcg/kg of fat, 5.6 mcg/kg of tissue) in the liver of a child aged 12 years. The results are comparable to those obtained in this country in the liver of adults and in human placenta.  相似文献   

3.
A 58-year old male with a past history of psychiatric disorders was studied for a persistent serum transaminase increase. Low serum ceruloplasmin level (lower than 3 mg/dL), increased urinary copper excretion, and increased liver tissue copper concentration (1050 mcg/g dry weight) confirmed the diagnosis of Wilsońs disease. Slit lamp examination did not show Kayser-Fleischer rings. D-penicilamin therapy was followed by serum transaminase normalization. Similar late-onset cases of Wilsońs disease are exceptional, but confirm the clinical heterogeneity of the disease.  相似文献   

4.
Amoxycillin levels were measured in the serum, bile, lung, gallbladder, and liver tissue in 19 cases of lung and 22 cases of cholecyst operations following intramuscular administration of 1 g amoxycillin. After 60-160 min, 4.4-5.6 mcg/g intact lung tissue and 1.5-3.9 mcg/g tumorous lung tissue concentrations were found, representing 41-48% and 15-32%, respectively, of the corresponding serum levels. Between 70 and 160 min when the ducts cysticus was open, the cystic bile contained 5.2-8.8 mcg/ml, the bile taken from the biliary ducts showed 10.9-13.2 mcg/ml, whereas the wall of the gallbladder and the liver tissue displayed 4.4-5.1 and 1.7-2.8 mcg/g amoxycillin levels. These levels represented 50-92, 118-136, 50-52 and 17-28% of the actual serum levels. As in the serum levels, the bile and tissue levels were about twice as high as those following ampicillin administration. The amoxycillin levels measured in the serum, bile, and other tissue tissues in most cases exceeded the minimal inhibitory concentrations for most of the bacteria usually considered. Therefore, amoxycillin can be applied successfully to treat respiratory and biliary infections.  相似文献   

5.
OBJECTIVES: To measure blood selenium concentration and glutathione peroxidase (GSH-Px) activity and serum concentrations of vitamin A and alpha-tocopherol, and to determine the correlation between blood selenium concentration and GSH-Px activity of llamas fed alfalfa hay. DESIGN: Mean (+/- SD) serum vitamin A and alpha-tocopherol concentrations, blood selenium concentrations, and GSH-Px activity were calculated from 9 sequential blood samples collected from llamas fed a diet of alfalfa hay. ANIMALS: 15 clinically normal llamas (8 males, 7 females) between 10 and 14 months of age. PROCEDURE: Llamas were fed alfalfa hay for 40 days prior to sample collection and then for the duration of the trial. Vitamin E, selenium, and concentrations of vitamin A precursors were measured in the hay. Blood samples were collected on days 0, 6, 7, 9, 13, 20, 42, 64, and 98. Blood selenium concentrations were measured, using an inductively coupled spectrometric method. Blood GSH-Px activity was measured with a spectrophotometer, using a modification of a previously described assay. Isocratic high-performance liquid chromatography with florescent detection was used to determine serum alpha-tocopherol and vitamin A concentrations. RESULTS: The alfalfa hay contained 0.2 mg/kg of selenium, 5 mg/kg of vitamin E, and 0.9 mg/kg of vitamin A precursors. The mean (+/- SD) blood selenium concentration and GSH-Px activity were 0.179 +/- 0.032 micrograms/ml and 25.76 +/- 6.53 mU NADPH oxidized/min/mg of Hb, respectively, with a correlation coefficient of 0.97. The mean (+/- SD) concentrations for serum alpha-tocopherol and vitamin A were 128.1 +/- 41.7 and 74.8 +/- 5.5 micrograms/dl, respectively. CONCLUSIONS: Blood selenium concentrations in llamas are highly correlated to GSH-Px activity. Blood selenium concentrations in llamas appear to be similar to other domestic ruminants and diets containing 0.2 mg/kg of selenium appear to provide an adequate dietary source. The concentrations of vitamin A precursors and vitamin E in the hay were below currently recommended dietary levels for llamas, and alfalfa hay appears to provide an unreliable source of vitamins A and E in this species. Further studies are required to determine optimal dietary concentrations and to substantiate a reference range for these vitamins in llamas.  相似文献   

6.
The hypothesis that low selenium may in some circumstances be a risk factor for lung cancer was investigated in a case-control study nested within a longitudinal study. Serum samples from 9,101 cancer-free individuals were collected and stored at -20 degrees C by the Finnish Mobile Clinic in 1968-1971 and 1973-1976. During follow-up until the end of 1991, 95 cases of lung cancer were diagnosed. Selenium concentrations were determined from the serum samples of the cases and 190 controls, individually matched for sex, age, and place of residence. Mean levels of serum selenium in cases and controls were 53.2 microg/liter and 57.8 microg/liter, respectively. The relative risk of lung cancer between the highest and lowest tertiles of serum selenium, adjusted for smoking, serum alpha-tocopherol, serum cholesterol, serum copper, serum orosomucoid, and body mass index (kg/m2), was 0.41 (95% confidence interval (CI) 0.17-0.94). The association was stronger at lower levels (<5.9 mg/liter) of alpha-tocopherol (relative risk=0.24, 95% CI 0.07-0.85). The association was also pronounced among current smokers and at higher levels of serum orosomucoid and serum copper. The relative risk for smokers who were twice ranked in higher selenium tertiles, at an interval of 4-7 years, in comparison with smokers who remained in the lowest tertile was 0.16 (95% CI 0.04-0.74). In accordance with the hypothesis, the findings suggest that very low selenium status may contribute to the risk of lung cancer.  相似文献   

7.
Effects of intramuscular injections of selenium and vitamin E on lesions in pigs with selenium-vitamin E deficiency syndrome were determined in 2 factorial experiments, using a total 69 pigs. The pigs were fed a selenium-vitamin E deficient, 22.3% protein ration, supplemented with methionine, minerals, and vitamins. Weekly intramuscular injections of isotonic saline solution, vitamin E, selenium, or vitamin E and selenium were given to the respective treatment groups. Selenium-vitamin E deficiency lesions occurred only in pigs that were given saline injections. Weekly intramuscular injections of either selenium (as selenous acid buffered to pH (7.3) at the rate of 0.05 mg/kg of body weight or vitamin E at the rate of 20 IU/kg of body weight or the combination of selenium and vitamin E prevented cardiac and skeletal myodegeneration, hepatic necrosis, and death. Significant increases of serum aspartate aminotransferase activity values were noted in pigs with liver, heart, or skeletal muscle lesions, but these increases were not correlated with the extent of the lesions. Vascular lesions, epicardial and endocardial hemorrhages, and yellow discoloration of body fat were not features of this experimentally induced disease. These lesions may be related to factors other than the deficiency of selenium, vitamin E, or selenium and vitamin E in rations previously used in reported studies.  相似文献   

8.
The changes in the serum level of selenium in cases with pathologic pregnancies are still not clear. The aim of the present study was to determine whether serum selenium in cases with missed abortion differed from selenium concentration in serum during first trimester of normal pregnancy. Twenty-three women with missed abortion and 61 with normal pregnancy were included in the study. We found a statistically significant (p < 0.001) elevation of serum selenium level in cases with missed abortion (928 +/- 335 nmol/l) comparing with those with normal pregnancy (568 +/- 77 nmol/l). We discuss the possible mechanisms of the observed changes.  相似文献   

9.
In Finland commercial fertilizers have been enriched with sodium selenate since July 1, 1984 in order to compensate for the poor selenium content of the soil. Fertilizers that are used for the production of hay and fodder were supplemented with 6 mg/kg of selenium, whereas fertilizers used for the production of cereals were supplemented with a higher dose, 16 mg/kg fertilizer. The effects of selenium fertilization were first seen in diary products in June 1985, and from the beginning of August 1985, the effect was evident also in wheat flour, beef, and bovine liver. In this study the selenium status of 108 healthy young adults has been systematically documented since November 1985, at which time the mean selenium serum level (S-Se) was 1.05 umol/L. A steady increase was observed until November 1989, when the maximum level, with a mean of S-Se 1.6 umol/L was reached. After that, a slight decrease has occurred. The mean serum selenium level in autumn 1991 in a new group of 35 students was 1.58 umol/L. This decrease can be explained by the high amount of imported cereals in 1988 and 1989, which was reflected also in the serum selenium levels. The glutathione peroxidase activity in erythrocytes in 1989-1990 was at the same level as in 1985 and 1986.  相似文献   

10.
The extent of interdialytic weight gain (IDWG) in chronic hemodialysis patients is usually attributed to the level of compliance with fluid restriction. However, in view of the substantial water content of food (and caloric content of beverages), IDWG also may be a function of calorie and protein intake and may reflect the nutritional state of patients. To investigate this theory, the relationship between 2-day IDWG and body weight, normalized protein catabolic rate (nPCR), serum albumin, and delivered Kt/V urea was assessed in a prospective, randomized study of 860 chronic hemodialysis patients in 56 dialysis units. Compared with patients having < 2 kg IDWG (n = 378), patients with > 3 kg IDWG (n = 138) weighed more (dry weight, 76.8 v 61.7 kg), had higher nPCR (1.15 v 0.96 g/kg/d), and had higher serum albumin levels (3.96 vs 3.79 g/dL) (all P < 0.001) but did not have different levels of Kt/V (1.04 v 1.06). When IDWG was assessed as a function of dry weight, patients with IDWG > 4.5% of dry weight (n = 151) had higher nPCR (1.17 v 0.94 g/kg/d) but weighed less (60.1 v 70.0 kg) and had a higher Kt/V (1.14 v 1.01) than patients with IDWG < 3% of dry weight (n = 355) (all P < 0.001). Artifactual association between IDWG and nPCR attributable to an accentuated two-pool effect from differing ultrafiltration requirements was unlikely as assessed by the relationship between modeled Kt/V and prescribed Kt/V determined using an anthropometric urea volume.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
Liver biopsies and serum samples were collected after intravenous application of 2 g cephradin (n = 13) or 2 g cephacetril (n = 11) during surgery. There was no difference in the serum levels of cephradin and cephacetril. 30 min. after i.v. application of cephradin the liver tissue concentration was 72.62 mcg/g. 30 min. after i.v. cephacetril the liver tissue concentration was 5.83 mcg/g. The quotient of liver tissue concentration to serum concentration for cephradin was between 0.36 and 0.83, and for cephacetril between 0.02 and 0.16. The excretion of cephradin and cephacetril in human bile was studied by collecting bile samples from the common bile duct via T-tube drainage (n = 17). Cholecystomized patients were given 2 g of antibiotics intravenously. Serum levels of cephradin were 263 mcg/ml 5 min after application, and 22 mcg/ml after 240 min. Serum levels of cephradin were 263 mcg/ml 5 min after application, and 22 mcg/ml after 240 min. Serum levels of cephacetril were 193 mcg/ml 5 min after application, and 27 mcg/ml after 240 min. The highest levels of cephradin in the bile were found 75 min after injection at a concentration of 86.4 mcg/ml; the highest level for cephacetril was 21.8 mcg/ml at 15 min. In patients with hyperbilirubinaemia cephradin reached a mean maximum concentration of 29.6 mcg/ml in bile samples, in comparison to 117.4 mcg/ml in normal patients, while no difference was seen with cephacetril. After intravenous administration of 2 g cephradin biliary concentration are achieved which may be sufficiently high to be effective not only against the very sensitive gram-positive organisms, but also against most strains of E. coli, Klebsiella and indol-negative Proteus. Cephradin is effective in the treatment of cholangitis and intrahepatic abscesses, as was observed in 18 patients. A free bile-flow is essential.  相似文献   

12.
Mean hair selenium of Managua citizens--743 mg/kg--was higher than of Moscow citizens. Significant differences were detected between groups of citizens with different social sighs: those with low income and perhaps irrational nutrition possess hair selenium value smaller (598 +/- 46 mg/kg) than those with relatively high income (713 +/- 40 mg/kg). Among recent country emigrants hair selenium was round to be the highest--898 +/- 60 mg/kg. This group of people possesses extremely low social status and consumes exclusively corn and beans. Wide interval of selenium concentrations for cereals of Nicaragua: 92 divided by 2580 mg/kg for corn and 18 divided by 814 mg/kg for beans--suggests mosaic selenium distribution in the soils of Nicaragua and consequently high possibility of different human selenium status levels.  相似文献   

13.
OBJECTIVE: We examined zinc (Zn) status in relation to thyroid function in disabled persons, because the association between Zn deficiency and thyroid function remains controversial. METHODS: After measuring serum free 3,5,3'-triiodothyronine (T3) and free thyroxine (T4) in 134 persons, TSH-releasing hormone (TRH) injection test and estimation of Zn status were conducted in persons with low free T3. RESULTS: Thirteen had low levels of serum free T3 and normal T4. Patients with elevated levels of serum 3,3',5'-triiodothyronine (rT3) showed an enhanced reaction of serum thyrotropin (TSH) after TRH injection. Nine of 13 patients had mild to moderate Zn deficiency evaluated by body Zn clearance and increased urinary Zn excretion. After oral supplementation of Zn sulphate (4-10 mg/kg body weight) for 12 months, levels of serum free T3 and T3 normalized, serum rT3 decreased, and the TRH-induced TSH reaction normalized. Serum selenium concentration (Type 1 T4 deionidase contains selenium in the rat) was unchanged by Zn supplementation. CONCLUSION: Zn may play a role in thyroid hormone metabolism in low T3 patients and may in part contribute to conversion of T4 to T3 in humans.  相似文献   

14.
The influence of hypervolemia on hemodynamics and interdialytic blood pressure, as well as in relation to vascular compliance, was investigated in 10 hemodialysis patients who were not receiving vasoactive medication. All subjects were studied during a relative normovolemic interdialytic period (from 1 kg below dry weight postdialytic until dry weight predialytic) and a hypervolemic interdialytic period (from 1 kg above dry weight postdialytic until 3 kg above dry weight predialytic). Interdialytic blood pressure was measured with an ambulatory blood pressure monitor. Cardiac output was echographically measured and total peripheral resistance calculated postdialytic, mid-interdialytic, and predialytic. At the same time, a blood sample was drawn for analyzing vasoactive hormones, sodium, and hematocrit. In all patients, ideal dry weight was estimated by echography of the caval vein. Arterial and venous compliance were measured with an ultrasound vessel wall movement detector system and a strain-gauge plethysmograph. After fluid load, an increase in intravascular volume, an increase in caval vein diameter and cardiac output, and a decrease in peripheral resistance was observed. No significant influence of a 3-L fluid load was found on interdialytic blood pressure course (153+/-24 mm Hg/90+/-19 mm Hg in the hypervolemic period and 146+/-27 mm Hg/89+/-22 mm Hg in the normovolemic period). Sodium and osmolality were similar in the hypervolemic and normovolemic interdialytic periods. After fluid load, a decrease in arginine vasopressin and angiotensin II was observed, which probably contributed to the decreased systemic vascular resistance. Catecholamines were not influenced by fluid load, but increased during the interdialytic period, suggesting accumulation after dialysis. Three of the 10 patients had higher systolic but not diastolic blood pressures after fluid load (159+/-13 mm Hg/81+/-22 mm Hg in the hypervolemic period and 135+/-16 mm Hg/81+/-22 mm Hg in the normovolemic period). No correlation could be found between arterial or venous compliance and blood pressure changes. We concluded that a 3-L interdialytic fluid load does not result in higher blood pressure in most hemodialysis patients.  相似文献   

15.
Glutathione peroxidase (GSHPx) was purified from human serum and used for immunization of rabbits. Antiserum bound up to 75% of added 125I-GSHPx after precipitation with a second antibody. Human serum, but not sera from eight animal species, inhibited the binding of labelled GSHPx, indicating that the antiserum did not react with GSHPx from these species. GSHPx could be measured in less than 10 microliters of human serum by radioimmunoassay. In sera with widely varying selenium concentrations (0.1-2.9 mumol/l) the amount of GSHPx protein (0.3-6.3 mg/l) was strongly correlated with GSHPx activity (r = 0.94) and it was also correlated with serum selenium concentrations (r = 0.64). This indicates that GSHPx protein may be a valuable biological marker of selenium status. In samples with serum selenium concentrations of 0.8-1.2 mumol/l, the concentration of GSHPx was 3.3 (0.4) mg/l (mean (S.D.)), or 0.04 (0.005) mumol/l. This corresponded to 0.16 (0.02) mumol/l of GSHPx selenium and 16% (2.8)% of total serum selenium. The data suggest that the method can be used to measure the proportion of serum selenium that is located in GSHPx. Following storage of serum at room temperature, both serum GSHPx protein and activity declined, but addition of glutathione protected both GSHPx protein and activity.  相似文献   

16.
Contradictory results have been published about the relation between copper, zinc and selenium and blood pressure (BP). To evaluate the role of these trace elements in BP regulation, we analysed the correlations between BP and copper, zinc and selenium, measured from serum, diet and hair among 3596 healthy children in a 6-year follow up. Fasting blood samples were used in serum copper, zinc and selenium analyses. The dietary intake of trace elements and energy were determined by the 48-h recall method. The hair copper and zinc analyses were performed from the naturally coloured hair samples. Correlation analysis was used to show the relation between BP and copper, zinc or selenium in each study year and during a 3- or 6-year follow-up period. The zinc-to-copper ratio in serum, diet and hair was calculated. In the correlation analyses the data was adjusted for weight and the daily intake of energy. Neither serum and diet copper or zinc, nor the zinc-to-copper ratio correlated uniformly with BP measured in the same year (correlation coefficients varying from -0.12 to 0.18) or in the subsequent years. Hair copper and zinc correlated weakly negatively with BP (correlation coefficients varying from -0.17 to -0.01). Serum selenium correlated weakly positively with systolic and diastolic BP measured in the same year (correlation coefficients varying from 0.03 to 0.14), but not with subsequent BP measured in the second or third survey. Dietary selenium had an inconsistent effect on BP (correlation coefficients varying from -0.14 to 0.26). In conclusion, copper, zinc, their ratio or selenium did not associate with BP, nor did they have any effect on subsequent BP.  相似文献   

17.
In the South Bohemian Region which is an area of enzootic incidence of nutritional muscle dystrophy selenium content in the fur of dairy cows and young cattle was determined. In the breeds in which the "white muscle disease" appeared in the past years in young cattle, lambs and calves the lowest mean selenium values in the fur dry matter found were: 0.18 +/- 0.07, 0.19 +/- 0.06, and 0.21 +/- 0.08 ppm, with repeated findings of mere 0.09 ppm Se. 60 to 100 per cent samples from these farms showed selenium values below the 0.25 ppm level. The fur of heifers which recovered from nutritional muscle dystrophy and were treated 10 days prior to sampling with a selenium preparation in injection form (Selevit inf. SPOFA) contained 0.29 ppm selenium (+/- 0.11). In other breeds 0.30 +/- 0.07 to 3.33 +/- 0.16 ppm selenium was found in the fur of cows and young cattle. The initial field essay of selenium content in cattle fur indicated a relation of low selenium values to the frequency of clinical forms of nutritional muscle dystrophy in domestic ruminants.  相似文献   

18.
Sulphur, selenium and nitrogen metabolism were studied in Merino wethers fed for 35-day periods on semipurified diets in which the sulphur content was increased to either 0-07 or 0-20% by the addition of sodium sulphate. At both levels of sulphur, additions of selenium as DL-selenomethionine increased the basal level of selenium (0-02 microgram/g) to 0-06, 0-09 and 0-67 microgram/g. Both levels of dietary sulphur supported positive sulphur balances but a reduction in sulphur intake per se resulted in a significant depression in dry matter digestibility (P less than 0-05), apparent nitrogen digestibility (P less than 0-05), nitrogen balance (P less than 0-01), sulphur balance (P less than 0-05) and plasma sulphate-sulphur (P less than 0-05) and wool (P less than 0-01) selenium levels. Selenium balance was not affected by differences in sulphate-sulphur intake. Selenium balances (P less than 0-001), plus the selenium levels in plasma (P less than 0-001), and wool (P less than 0-001) were significantly different at the different levels of selenium supplementation. A positive selenium balance was achieved when the selenium intake was approximately 37 microgram/day, regardless of sulphur treatment. The validity of using plasma and/or wool selenium levels as indices of the selenium status of sheep is questioned.  相似文献   

19.
Antagonistic toxic effects of selenium and lead were studied in growing rats. Chronic lead intoxication was produced by cutaneous application of lead naphthenate solution (80-200 mg Pb/kg body weight) for a period of 8 weeks and chronic selenium intoxication was induced by giving 5 ppm, 10 ppm and 15 ppm selenium in drinking water. The growth rate and food consumption of rats receiving selenium in addition to lead approached normal rate while animals treated with only one of them showed hampered growth rate and lower food consumption. The enzymatic activity of delta-aminolevulinic acid dehydrase (ALA-D) in whole blood, liver and kidney and liver P-450 enzyme activity were normal in rats receiving both selenium and lead. The enzymic activities assayed were, however, depressed in the animals receiving either lead or selenium. Assay of lead and selenium in liver, brain, kidney and blood was carried out. Rats receiving both metals and higher concentrations of these metals in the organs studied, as compared to those only receiving one component. The data seem to indicate that the effect of selenium on the toxic effects of lead is similar to its protective role against methylmercury intoxication.  相似文献   

20.
There are no data in the literature on effects of supplementing infants with yeast-selenium. We therefore studied the impact of selenium-enriched yeast on the serum selenium concentration of preterm infants living in a selenium-low area (Hungary). Twenty-eight preterm infants with a mean +/- SD birthweight of 962 +/- 129 g and a gestational age of 27 +/- 1 weeks were randomized into two groups at birth with respect to selenium supplementation. In the supplemental group (n = 14) infants received 4.8 mg yeast containing 5 microgram selenium daily with naso-gastric drip during the first 14 postnatal days. The nonsupplemented infants were used as a reference group. In the supplemented group the serum selenium concentration increased from 32.1 +/- 8.5 microgram/l to 41.5 +/- 6.5 microgram/l and in the nonsupplemented group it decreased from 25.9 +/ 6.8 microgram/l to 18.2 +/- 6.4 microgram/l within two weeks. The serum glutathione peroxidase activity increased from 2.97 +/- 0.73 U/20 microliter to 6.42 +/- 3.11 U/20 microliter in the supplemented group, and it did not change significantly (from 3.53 +/- 0.94 U/20 microliter to 3.85 +/- 0.95 U/20 microliter) in the nonsupplemented group. We did not observe any complications or side effects in connection with enteral yeast-selenium supplementation. It is concluded that selenium-enriched yeast is a safe and an effective form of short term enteral selenium supplementation for preterm infants.  相似文献   

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