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1.
The pathogenesis of heart disease has been associated with changes in the balance of certain trace elements. The aim of this study was to evaluate the Zn, Fe, Cu, Cr, Ni, Pb, and Cd contents in scalp hair samples of myocardial infarction (MCI) patients hospitalized in the cardiac ward of National Hospital in Hyderabad city (Pakistan). Scalp hair samples were collected from 193 patients (104 male, 89 female) of 3 age groups (46–60, 61–75, and 76–90 yr), for a comparative study, 200 normal, healthy subjects (103 male, 97 female) of the same age groups residing in the same city were selected. All metals in scalp hair samples were assessed by a flame/graphite furnace atomic absorption spectrophotometer, prior to microwave-assisted and conventional wet acid digestion methods. Results were calculated in micrograms per gram. The mean values of Fe and Zn of scalp hair samples of MCI patients were significantly reduced compared to the control subjects of both genders. The mean Fe concentrations in male patients were 19.42, 12.36, and 6.98 vs 30.69, 24.42, and 16.75 for the control patients in the three age groups (46–60, 61–75, and 76–90 yrs, respectively). The mean Zn concentration in male patients were 169.2, 149.4, and 107.7 μg/g vs 206.1, 188.0, and 154.4 μg/g for the control group (p<0.002, 0.004, and 0.001) in all three age groups, respectively. These differences were also observed in the female study groups. The mean values of Pb, Cd, and Ni were significantly high in patients compared to healthy subjects (mean Pb in male patients: 11.85, 12.89, and 14.52 those of female patients were 11.88, 12.73, and 14.21 vs the male controls patients (6.08, 7.56, and 8.56) and female controls (5.99, 7.41, and 8.25) for all three age groups, respectively. The concentration of Ni and Cd in the scalp hair samples of the heart patients of both sexes were significantly higher compared to the control; in the case of Ni the range of significant difference for males was found to be p<0.001–0.009 and for females to be p<0.0.002–0.007 and significantly high concentration of Cd were observed in hair samples of patients than in controls in the range for males (p<0.001–0.009) and in females (p<0.001–0.011). The Zn/Cu and Zn/Cd ratios in the scalp hair (p<0.01) of the diseased groups were significantly lower than that of the healthy groups. Deficiency of essential trace metals and high level of toxic metals might play a role in the development of heart disease in the subjects of this study. Toxic metals might also cause diminished absorption of essential elements.  相似文献   

2.
Two-wk-old broiler chicks were inoculated via crop intubation withEimeria acervulina at two doses: 105 or 106 sporulated oocysts/bird or withEimeria tenella at a dose of 105 sporulated oocysts/bird. Serum and liver samples were collected on days 3 and 6 post-inoculation (PI). There were no significant changes in serum or liver zinc, copper, and iron concentrations in any of the infected groups by 3 d PI. However, on d 6, PI serum protein was significantly reduced in all of the infected groups compared to their pair-fed controls. The chicks infected withE. tennella had significantly reduced serum zinc (1.20 vs 1.77 μg/mL) and iron (0.44 vs 1.28 μg/mL) concentrations and significantly elevated serum copper (0.28 vs 0.17 μg/mL) and ceruloplasmin levels (20.33 vs 11.11 μg/mL) compared to their pair-fed counterparts. Those chicks infected withE. acervulina (106 oocysts/bird) exhibited significantly reduced serum iron concentration by 6 days PI (0.90 vs 1.14 μg/mL). Liver zinc was significantly increased in the chicks infected withE. tenella (349 vs 113 μg/g dry liver wt), as was copper (24 vs 19 μg/g), whereas liver iron concentration was significantly reduced (172 vs 243 μg/g) compared to pair-fed controls. At both dose levels, the chicks infected withE. acervulina exhibited a significant reduction in liver iron by 6 d PI. Hepatic cytosol metals generally reflected whole tissue levels. Metallothionein (MT)-bound zinc was significantly elevated in the chicks infected withE. tenella. Iron bound to a high molecular weight, heat-stable protein fraction (presumably cytoplasmic ferritin) was significantly reduced in chicks infected withE. acervulina, as well as those infected withE. tenella. Collectively, the changes in serum zinc, copper, and iron concentrations, as well as the changes in hepatic zinc and MT-zinc concentrations in the chicks infected withE. tenella were similar to changes evoked during an acute phase response to infection. It is possible that a secondary bacterial infection or inflammation stemming from erosion of the lining of the cecum may play a role in the response of trace element metabolism to theE. tenella infection. Mentions of a trademarkr, proprietary product or specific equipment does not consitute a guarantee or warranty by the US Department of Agriculture and does not imply its approval to the exclusion of other products.  相似文献   

3.
The concentrations of cadmium, lead, selenium, and zinc in blood and seminal plasma were determined in 76 Singapore males. Except for zinc, the concentrations were generally higher in blood than in seminal plasma (cadmium, 1.31 μg/L vs 0.61 μg/L; lead, 82.6 μg/L vs 12.4 μg/L, and selenium, 163.6 μg/L vs 71.5 μg/L). The mean concentration of zinc in seminal plasma was more than 30 times higher than in blood (202 mg/L vs 6.2 mg/L). Significant positive correlations were found between the concentrations in blood and seminal plasma for the two essential trace elements: selenium (r=0.45,p<0.001) and zinc (r=0.25,p<0.05). However, no relationships were found between the concentrations in blood and seminal plasma for two toxic metals (cadmium and lead). Significant inverse correlations were observed between Cd and Zn (r=−0.40,p<0.01), and Pb and Se (r=−0.32,p<0.05) in blood, whereas significant positive correlations were noted between Cd and Se (r=0.45,p<0.01), Cd and Zn (r=0.35,p<0.05), and Se and Zn (r=0.57,p<0.001) in seminal plasma. The physiological significance of these relationships are also discussed in this paper.  相似文献   

4.
It is known that certain trace elements can affect various heart diseases. In this study, we aimed to evaluate the changes in concentrations of certain serum trace elements in patients with chronic rheumatic heart disease (RHD). Serum analysis of selenium (Se), zinc (Zn), and copper (Cu) trace elements was assayed by atomic absorption spectrophotometry. RHD patients had significantly lower serum concentrations of Se and Zn than control subjects (p<0.05 and p<0.001, respectively). However, the serum Cu concentration was significantly higher in RHD patients than in controls (1.93±0.59 μg/L vs 1.06±0.29 μg/L; p<0.001). Similarly, the Cu/Zn ratio in RHD patients was higher than in control subjects (4.70±0.92 vs 1.68±0.45; p<0.001). Additionally, no significant correlation was found among these trace element concentrations and the functional capacity classes (p>0.05). RHD patients had decreased serum Se and Zn element concentrations and increased serum Cu element concentration. We suggest that Se and Zn deficiency might be contributory factors in the development of rheumatic heart disease, and a high Cu concentration and a high Cu/Zn ratio might reflect an ongoing inflammatory process in this disease.  相似文献   

5.
Hair samples of 15 adult male Atlantic walruses (Odobenus rosmarus rosmarus) collected from anaesthetized individuals at Svalbard, Norway, were analysed for cadmium and total mercury. The mean level of cadmium was 0.860 ± 0.321 μg/g dry weight (median = 0.811, range = 0.349–1.51 μg/g dry weight) and the mean level of mercury was 0.235 ± 0.100 μg/g dry weight (median = 0.251, range = 0.121–0.424 μg/g dry weight). Levels of cadmium and mercury in hair of walruses from other areas are not known. Both cadmium and mercury levels in hair of walruses from Svalbard are relatively low compared to the levels found in the hair of other marine mammal species. It has been documented from a number of marine species, including marine mammals such as ringed seals and polar bears, that both cadmium and mercury levels at Svalbard are lower than in other areas. It is uncertain as to what degree levels in hair reflect levels in internal organs in walruses. In rare and highly endangered species or populations tissue samples can be difficult to collect. In walruses, it is possible to collect hair from anaesthetized individuals or at the haul-out sites during moult, to monitor heavy metal levels of the population. Accepted: 6 December 1998  相似文献   

6.
In two fully crossed, three-way, two by three by three, factorially arranged experiments, female weanling rats were fed a basal diet supplemented with iron at 15 and 45 μg/g, nickel at 0, 5, and 50 μg/g and copper at 0, 0.5, and 5 μg/g (Expt. 1) or 0, 0.25, and 12 μg/g (Expt. 2). Expt. 1 was terminated at 11 weeks, and Expt. 2 at 8 weeks because, at those times, some rats fed no supplemental copper and the high level of nickel began to lose weight, or die from heart rupture. The experiments showed that nickel interacted with copper and this interaction was influenced by dietary iron. If copper deficiency was neither very severe or mild, copper deficiency signs of elevated levels of total lipids and lipid phosphorus in liver and plasma, and cholesterol in plasma, were made more severe by supplemental dietary nickel. Rats in which nickel supplementation exacerbated copper deficiency did not exhibit a depressed level of copper in liver and plasma. Also, although iron deprivation enhanced the interaction between nickel and copper, iron deprivation did not significantly depress the level of copper in liver and plasma. The findings confirmed that, in rats, a complex relationship exists between nickel, copper, and iron, thus indicating that both the iron and copper status of experimental animals must be controlled before data about nickel nutriture and metabolism can be compared among studies.  相似文献   

7.
The subantarctic Kerguelen Islands (49°S, 70°E) contain freshwaters among the most isolated in the world from direct human activities. Cadmium and copper concentrations were analyzed in muscle and liver tissues of 57 non-migratory brook trout (Salvelinus fontinalis) inhabiting the Sud River of Kerguelen Islands. The mean cadmium concentration in liver was 1.13 μg/g dry wt, within the range of levels measured in liver of marine fish from the Southern Ocean. Muscular Cd levels (0.12 μg/g dry wt) were roughly ten times higher than those measured in Kerguelen’s marine fish species. Copper levels were very high in the two organs (62.27 μg/g dry wt in liver and 3.02 μg/g dry wt in muscle) compared to those detected in fish from the Southern Ocean. Regarding the seasonal trend, the highest Cu and Cd muscular levels were measured in fish at the end of the austral winter, whereas the highest hepatic levels were observed at the end of the austral summer. Moreover, hepatic cadmium levels were higher in females than in males. These results could be related to brook trout spawning physiological preparations and foraging behavior during the summer period. We provide here the first results about Cu and Cd levels in liver and muscle of a freshwater fish species in an insular subantarctic context. They are in agreement with the high cadmium contamination found in fish of the Southern Ocean.  相似文献   

8.
Determination of Rb, Br, Se, Zn, Cu, Fe, and Br/Rb ratio in tissues of mice inoculated with colon and melanoma cancer cells is described. A group of 19 Balb/c mice inoculated with C26 colon carcinoma, 4 C57B1/6 mice inoculated with B16 melanoma, and 13 control mice of both kinds were under investigation. The study was conducted on samples of blood, liver, kidneys, colon, and skin, and the trace element levels in normal and inoculated mice were compared. The inoculation was by subcutaneous injection either at the back or intrafootpad. The blood samples were taken 1, 2, and 3 wk after inoculation, and after 4 wk all the animals were sacrificed. Two nondestructive, complementary analytical methods were used: a modified X-ray fluorescence (XRF) for solid tissue and particleinduced X-ray emission (PIXE) for blood samples. The detection limit (DL) in the PIXE method was 0.35 (μg/g dry wt in 600 s counting time and in XRF, 1 μg/g dry sample for Rb, Br, Se and Zn and 2 μg/g for Cu and Fe in 200 s counting time. In all the cases studied, cancerous tissue developed at the site of the injection, and a significant difference in the trace element levels was observed between tissue samples obtained from normal and inoculated mice. The most pronounced effect was an increase in Rb level in the tumor by a factor ranging between 4 and 10 relative to normal tissue, with a corresponding decrease in the Br/Rb ratio (p < 0.05). Smaller changes were found in the Br, Se, Zn, and K levels. The changes in trace element levels in the inner organs were much smaller and seem to be influenced by the site of injection.  相似文献   

9.
Cardiotoxicity represents the main drawback of clinical usefulness of anthracycline antineoplastic drugs. In this study, a content of selected elements (Ca, Mg, K, Se, Fe) in the post-mortem removed samples of the myocardial tissue was studied in three groups of rabbits: 1) control group (i.v. saline; n = 10); 2) daunorubicin-receiving animals (DAU; 3 mg/kg, i.v; n=11); 3) animals receiving cardioprotective iron-chelating agent dexrazoxane (DEX; 60 mg/kg, i.p.; n=5) prior to DAU. Drugs were administered once weekly for 10 weeks. 5–7 days after the last administration, cardiac left ventricular contractility (dP/dtmax) was significantly decreased in DAU-treated animals (745 ± 69 versus 1245 ± 86 kPa/s in the control group; P < 0.05), while in the DEX+DAU group it was insignificantly increased (1411 ± 77 kPa/s). Of the myocardial elements content studied, a significant increase in total Ca against control (16.2 ± 2.4 versus 10.6 ± 0.9 g/g of dry tissue; P < 0.05) was determined in the DAU-group, which was accompanied with significant decreases in Mg and K. In the heart tissue of DEX-pretreated animals, no significant changes of elements content were found as compared to controls, while the Ca content was in these animals significantly lower than in the DAU group (9.1 ± 0.4 versus 16.2 ± 2.4 g/g; P < 0.05). Hence, in this study we show that systolic heart failure induced by chronic DAU administration is primarily accompanied by persistent calcium overload of cardiac tissue and the protective action of DEX is associated with the restoration of normal myocardial Ca content.Published online: March 2005  相似文献   

10.
The association between elevated blood pressure and blood cadmium and mercury levels was examined (2001–2002) in 185 Saudi women previously selected for a case-control study of lead and hypertension risk. Blood pressure was measured twice according to the World Health Organization recommendations. Cadmium and mercury were determined with graphite furnace and hydride system-atomic absorption spectrometry, respectively. Mean blood cadmium concentrations were 0.874±0.995 μg/L in hypertensive and 0.785±0.665 μg/L in controls. While blood mercury concentrations for hypertensives and controls were 3.506±3.617 μg/L and 3.687±3.186 μg/L, respectively. Participants were classified according to the median of blood cadmium and mercury levels. After adjustment for potentially confounding variables, the final logistic regression analyses revealed that women with blood cadmium ≥0.627 μg/L were 3.934 times were more likely to be hypertensive than those with blood cadmium levels <0.627 μg/L, although this was marginally significant (p=0.098). This was likely the result of the small number of subjects, resulting in the weak power to detect a strong significant difference between hypertensives and control cases. On the other hand, the final regression model showed no association between hypertension and mercury. However, this finding should not be conclusive because of the inappropriate choice of the biomarker indicator. Nevertheless, our study supports the hypothesis that exposure to cadmium might increase the risk of hypertension.  相似文献   

11.
 Triacontanol, a long-chain primary alcohol was found to be an effective growth regulator in the micropropagation of balm, Melissa officinalis. In both the multiplication and the rooting phase, concentrations of 2, 5, 10 and 20 μg triacontanol per liter were applied. After 4 weeks of culture, the fresh weight of shoots was measured in the multiplication phase and root formation, photosynthetic activity, chlorophyll content and the fresh and dry weights of shoots were analyzed in the root induction phase. In the multiplication phase, 5 μg/l triacontanol was found to be the optimal concentration, while in the rooting phase 2 μg/l was the most effective. Triacontanol increased the number and length of roots, and it enhanced shoot growth, fresh weight, and the chlorophyll content, but it had no effect on the dry weight and the photosynthetic activity of the plants. Results of our work demonstrate that triacontanol can be applied as an effective growth regulator in the tissue culture of balm. Received: 3 December 1997 / Revised: 24 February 1998 / Accepted: 26 February 1999  相似文献   

12.
The influence of long-term exposure to cadmium (Cd) on essential minerals was investigated using a Caco-2 TC7 cells and a multi-analytical tool: microwave digestion and inductively coupled plasma mass spectrometry. Intracellular levels, effects on cadmium accumulation, distribution, and reference concentration ranges of the following elements were determined: Na, Mg, Ca, Cr, Fe, Mn, Co, Ni, Cu, Zn, Mo, and Cd. Results showed that Caco-2 TC7 cells incubated long-term with cadmium concentrations ranging from 0 to 10 μmol Cd/l for 5 weeks exhibited a significant increase in cadmium accumulation. Furthermore, this accumulation was more marked in cells exposed long-term to cadmium compared with controls, and that this exposure resulted in a significant accumulation of copper and zinc but not of the other elements measured. Interactions of Cd with three elements: zinc, copper, and manganese were particularly studied. Exposed to 30 μmol/l of the element, manganese showed the highest inhibition and copper the lowest on cadmium intracellular accumulation but Zn, Cu, and Mn behave differently in terms of their mutual competition with Cd. Indeed, increasing cadmium in the culture medium resulted in a gradual and significant increase in the accumulation of zinc. There was a significant decrease in manganese from 5 μmol Cd/l exposure, and no variation was observed with copper.  相似文献   

13.
The quality of the diet of obese children is poor. Eating habits may alter micronutrient status in obese patients. In this study, we determined the serum levels of selenium, zinc, vanadium, molybdenum, iron, copper, beryllium, boron, chromium, manganese, cobalt, silver, barium, aluminum, nickel, cadmium, mercury, and lead in obese Turkish children. Thirty-four obese and 33 healthy control subjects were enrolled in the study. Serum vanadium and cobalt levels of obese children were significantly lower than those of the control group (0.244 ± 0.0179 vs. 0.261 ± 0.012 μg/l, p < 0.001, and 0.14 ± 0.13 vs. 0.24 ± 0.15 μg/l, p = 0.011, respectively). There was no significant difference between groups regarding the other serum trace element levels. In conclusion, there may be alterations in the serum levels of trace elements in obese children and these alterations may have a role in the pathogenesis of obesity.  相似文献   

14.
IGF-I regulates lactation by stimulating mammary mitogenesis, inhibiting apoptosis, and partially mediating the effects of growth hormone on lactogenesis. Herein, lactation performance during first and second parity was assessed in transgenic swine (TG) that over-expressed human IGF-I in milk under the control of the bovine α-lactalbumin promoter, regulatory regions and signal peptide coding sequence. Milk samples were collected throughout lactation (farrowing to d24) from TG sows and non-transgenic littermates (CON) and IGF-I, IGF-II, and IGFBP determined. Colostral (<24 h postpartum) IGF-I content was 26-fold greater (p < 0.001) in TG sows (949 ± 107 μg/L; range 228–1600 μg/L) than CON (36 ± 17.8 μg/L) and was 50- to 90-fold greater (p < 0.001) in mature milk (d2-24 postpartum). There was no effect of parity on milk IGF-I content. Milk IGF-II concentration was unaffected by IGF-I over-expression. Low molecular weight IGFBP (IGFBP-2 and -5) in the milk of TG sows were higher (p = 0.02) than CON in the early postpartum period, but did not differ in mature milk. Milk yield, determined by weigh-suckle-weigh, was similar in TG and CON as was litter weight gain. Milk nutrient composition was not significantly affected by IGF over-expression. Thus, mammary specific transgenic over-expression of IGF-I significantly increased milk IGF-I and IGFBP content, but did not impact lactation performance in swine.  相似文献   

15.
Lithium in scalp hair of adults,students, and violent criminals   总被引:2,自引:0,他引:2  
The lithium content of human hair shows an approximately linear response to extradietary lithium supplementation at dosage levels of up to 2000 μg/d. From the mean hair lithium concentration of 0.063 μg/g in 2648 predominantly American adults, and the reference hair lithium concentrations determined in the present study, the mean lithium intakes were calculated to be 730 μg/d. Hair lithium concentrations were extremely low in nearly 20% of the American samples, and in samples collected in Munich, Germany and Vienna, Austria. Hair lithium levels are low in certain pathological conditions, e.g., heart disease, in learning-disabled subjects, and in incarcerated violent criminals. The highest levels were observed in samples of a lithium-treated psychiatric patient. A statistically highly significant direct association was observed between the hair lithium and cobalt concentrations, which suggests a role of lithium in the transport and distribution of vitamin B12. Interactions of lithium with other trace elements are also discussed.  相似文献   

16.
Muscle, liver, and kidney tissues from 38 polar bears (Ursus maritimus) caught in the Scoresby Sound area, Central East Greenland, were analysed for zinc, cadmium, mercury and selenium. In general, cadmium concentrations were low in muscle, liver and kidney tissue, with geometric means (g.m.) of 0.022 (range: <0.015–0.085), 0.841 (range: 0.092–3.29) and 13.1 (range: 1.04–115) g Cd/g wet weight (ww) respectively. This finding can be explained by low cadmium levels in the blubber of ringed seals. The concentration of mercury in muscle tissue was low (g.m. 0.071; range: 0.039–0.193 g Hg/g ww), whereas concentrations in liver and kidney tissue were relatively high (liver: g.m. 7.87; range: 1.35–24.8 g Hg/g ww, and kidney: g.m. 15.2; range: 1.59–66.6 g Hg/g ww). Mercury and cadmium were positively correlated with age in liver and kidney. Zinc was positively correlated with age in kidney, and selenium was correlated with age in liver. Contrary to other marine mammals, polar bears had higher mercury levels in the kidneys than in the liver. In all three tissues polar bears had significantly lower cadmium levels than ringed seals from the same area. Mercury levels were likewise significantly lower in the muscle tissue of polar bears than in ringed seals, whereas levels in the liver and kidney were significantly higher. The previous geographic trend for cadmium and mercury found in Canadian polar bears could be extended to cover East Greenland as well. Hence cadmium levels were higher in Greenland than in Canada, while the opposite was the case for mercury. Greenland polar bears had higher mercury and cadmium contents in livers and kidneys than polar bears from Svalbard. The mercury levels in muscle and liver tissue from polar bears from East Greenland were twice as high as found in bears from western Alaska, but half the levels found in northern Alaska. Cadmium and zinc were partially correlated in kidney tissue, and this was found for mercury and selenium as well. Cadmium and zinc showed molar ratios close to unity with the highest concentrations occurring in kidney tissue, while the levels of zinc exceeded cadmium in muscle and liver tissue by up to several decades. Mercury and selenium showed molar ratios close to unity in liver and kidneys.  相似文献   

17.
The serum selenium (Se) concentrations were determined to be 105.6±15.6 μg/L ( ) and 116.7±18.4 μg/L ( ) for the ovarian cancer patients and the control subjects in Singapore, respectively (p<0.0065). When we separated the patients into three age groups, namely <30, 30–50, and >50 yr, the ovarian cancer patients showed significantly lower mean serum Se levels than the control subjects for the 30–50-yr age group only. However, when the analysis of variance was used to evaluate the data, the values indicated that the age of the subject did not significantly affect the serum Se level. Our findings suggest that there is an inverse relationship between serum Se concentration and the incidence of human ovarian cancer. A modified simple fluorimetric method for the determination of serum Se concentration is described. The procedure, with a sensitivity limit of 5 μg/L and percentage recoveries of 96.2–100.7%, requires only 0.2 mL of serum sample.  相似文献   

18.
The levels of, zinc, copper, Fe, Zn, Cu, Mn, Mg, K, Na, and Cl and the activity of carbonic anhydrase were determined in lambs with pneumonia. A significant decrease of p<0.01 level in Zn concentration, in Cu level (p<0.001) and significant increases in K and Na levels (p<0.05) and of the Cu/Zn ratio (p<0.001) were observed in the study group. The carbonic anhydrase activity was decreased in the study group, but the decrease was not statistically significant (p>0.05). Also, nonsignificant decreases of Fe, Mg, and Cl and increase of the Mn concentration were also observed in the lambs with pneumonia (p>0.05). Our results suggest that the significant element changes reported here and the Cu/Zn ratio, but not the activity of carbonic anhydrase, can be used as indicators of pneumococcal infection.  相似文献   

19.
The aim of this study was to determine concentrations of selenium in the liver and kidneys of roe deer and red deer from West Pomerania, depending on the season. Altogether, samples from 169 animals were collected (96 from roe deer and 73 from red deer) in 2003–2007. The mean concentration of selenium in the liver of red deer and roe deer was 0.37 μg/g and 0.62 μg/g dry weight, respectively. In kidneys, Se concentration was 2.72 μg/g d.w. in red deer and 2.99 μg/g d.w. in roe deer. In roe deer, liver selenium concentration in autumn was significantly higher than in winter (P < 0.05) and spring (P < 0.01) and significantly lower in spring than in summer (P < 0.05); likewise, kidney selenium concentration was higher in autumn than in summer. In deer, no statistically significant season-related differences were observed for liver selenium concentrations. In red deer kidneys, selenium concentration was the lowest in summer, significantly lower than in autumn and winter. Low selenium concentrations in the analyzed tissues show that the animals live in areas deficient in this element.  相似文献   

20.
Juvenile and young adult specimens ofCarcinus maenas were kept in the laboratory under controlled conditions. The main organic constituents and their variations during the molt cycle were quantitatively determined.
1.  During postmolt the chitin concentration rises rapidly (20–74 mg/g dry weight) in parallel to the dry weight (120–293 mg/g fresh weight). Both decrease again before ecdysis (Fig. 1).
2.  The glycose level in the hemolymph (50–80 g/ml) shows no significant variation during the molt cycle (Fig. 2).
3.  The glycogen concentrations in integument, (14–180 mg/g dry weight), gills (5.5–66 mg/g dry weight), muscle (8.8–41 mg/g dry weight), heart (135–308 mg/g dry weight) and hemolymph (160–690 g/ml) reach their maximum values during the premolt stage. The highest glycogen content in the midgut gland (83 mg/g dry weight) is observed immediately before and after ecdysis. Glycogen storage in heart and hemolymph, can, account for about half of the glycogen stored in the midgut gland (Figs. 3,4 and 5).
4.  The lipid concentration in the hemolymph (120–440 g/ml) and in gills (33.6–70 mg/g dry weight) rises during the premolt stage (Figs. 6 and 7).
5.  The protein concentration in the hemolymph increased during premolt (9–31 mg/ml). The copper content (13–42 g/ml) varies in parallel to the protein concentration indicating that the proportion of hemocyanin to total proteins remains constant during the molting cycle (Fig. 8).
  相似文献   

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