[ Objective] TO further explore the mechanism of retained fetal membrane （RFM） of dairy cows in Qinghai Province. [ Methed] As many as 15 dairy cows with retained fetal placenta and 15 without retained fetal placent...[ Objective] TO further explore the mechanism of retained fetal membrane （RFM） of dairy cows in Qinghai Province. [ Methed] As many as 15 dairy cows with retained fetal placenta and 15 without retained fetal placenta were selected. The serum concentrations of eight metal ions, namely, potassium, sodium, calcium, magnesium, copper, iron, zinc and manganese at parturition and 12 h post partum were determined by atomic absorption spectrometry. The anti-oxidative indexes at parturition were determined by UV-1601 doub｜e-beam visib｜e spectrophotometer. ~=- sultl In the dairy cows with retained fetal placenta, the concentrations of calcium, magnesium, copper, zinc and manganese were decreased signif- icantly （ P 〈 0.05） ; that of iron was increased significantly （ P 〈 0.01 ） ; those of potassium and sodium did not change greatly; the activities of su- peroxide dismutase and glutathione peroxidase were decreased significantly （ P 〈 0.01 ） ; and the MDA content was increased significantly （ P 〈 0.05）. However, the concentrations of the eight metal ions and anti-oxidative indexes did not change in the dairy cows without retained fetal placen- ta, [ CondusionJ The RFM of dairy cows has some relationships with the serum concentrations of metal ions and antioxidation.展开更多
In this paper is reported a new method of determining serum albumin with potentiometry. The silver ion selective electrode was used as working electrode and S. C. E as reference electrode. By controlling the ionic s...In this paper is reported a new method of determining serum albumin with potentiometry. The silver ion selective electrode was used as working electrode and S. C. E as reference electrode. By controlling the ionic strength, PH and temperature constant, a good linear relationship was obtained between the cell potential and albumin concentration. This method .possessed characters-of operating simplicity, rapidity and directness. The samples could be detected directly and the results were in accordance with the values detected by classic K method.展开更多
Eleven chelating agents were studied for their capabilities to mobilize the cadmium bound tp bovine serum albumin(BSA).The parameter F,which is defined as the ratio between the percentages of cadmium bound to BSA in t...Eleven chelating agents were studied for their capabilities to mobilize the cadmium bound tp bovine serum albumin(BSA).The parameter F,which is defined as the ratio between the percentages of cadmium bound to BSA in the presence and absence of chelating agents,can be used as the criterion to evaluate the mobilizing capability of chelating agent.The F values determined experimentally lead to a mobilizing capability order:DTPA>EDTA>EGTA>NTA>TR1EN>PEN>CYS>HIS>SAThe polyaminopolycarboxylate type chelators mobilize cadmium effectively.A linear relationship was found between 1gF and lg k'CdL (conditional stability constant of the cadmium chelate).展开更多
The binding mechanism of the interactions of halide ions (F–, Br– and I–) with bovine serum albumin (BSA) and hemoglobin (Hb) were studied at different temperatures, by using ion-selective electrodes. The experimen...The binding mechanism of the interactions of halide ions (F–, Br– and I–) with bovine serum albumin (BSA) and hemoglobin (Hb) were studied at different temperatures, by using ion-selective electrodes. The experimental data were treated according to Klotz equation, and the number of binding sites and the binding constants were determined. The results show that the binding sites of F– on protein molecules are more than those of Br– and I–. Additionally, the number of the binding sites for halide ions on protein molecules increases with increasing temperature. This study also indicates that the binding constants for the interactions of halide ions with proteins gradually decrease as the size of halide ions and temperature increases. These behaviors were reasonably interpreted with the structural and thermodynamic factors. The thermodynamic functions at different temperatures were calculated with thermodynamic equations, and the enthalpy change for the interactions were also determined by isothermal titration calorimetry (ITC) at 298.15 K, which indicate that the interactions of halide ions with proteins are mainly electrostatic interaction.展开更多
We evaluated the ability of juvenile Amur sturgeon (Acipenser schrenckii) to osmoregulate and grow in saltwater. Hatchery-reared juveniles (mean weight 106.8 g, 5-month old) were transferred from freshwater to 10, 20,...We evaluated the ability of juvenile Amur sturgeon (Acipenser schrenckii) to osmoregulate and grow in saltwater. Hatchery-reared juveniles (mean weight 106.8 g, 5-month old) were transferred from freshwater to 10, 20, and 25 salinity saltwater over a period of 20 d. We measured the growth, serum osmolality, ion concentrations, and Na+/K+-ATPase activity. In addition, we prepared samples of gill tissue to quantify morphological changes in gill ultrastructure. Rearing in up to 25 saltwater for 30 d had no significant effect on growth. Similarly, serum osmolality and ion concentrations were similar to levels reported in other teleosts following acclimation to saltwater. Serum osmolality and Na+, Cl- concentrations increased significantly with the initial increase in salinity. Afterwards, levels tended to stabilize and then decrease. Serum K+ levels did not change during acclimation to saltwater. Gill Na+/K+-ATPase activity increased initially as salinity was increased. However, the activity later decreased and, finally stabilized at 3.7±0.1 μmol Pi/mg·prot·h in 25 saltwater (1.6 times higher than the level in those in freshwater). In fish that were held only in freshwater, the chloride cells were located in the interlamellar regions of the filament and at the base of the lamella. Following acclimation to 25 saltwater for 30 d, the number and size of chloride cells increased significantly. Our results suggest that juvenile Amur sturgeon is able to tolerate, and grow in, relatively high concentrations of saltwater.展开更多
In this article, a novel strong interaction by forming complex between bovine serum albumin （BSA） and copper ion was utilized for the preparation of molecular imprinted bydrogel in aqueous solution. Results show tha...In this article, a novel strong interaction by forming complex between bovine serum albumin （BSA） and copper ion was utilized for the preparation of molecular imprinted bydrogel in aqueous solution. Results show that the inclusion of copper ion in preparation can bridge the template BSA and functional monomers together and improve the imprinting effect compared to the polymer made without copper ion added. High selectivity factor and large adsorption capacity are also observed for the obtained BSA-imprinted hydrogel.展开更多
The loss of electrolyte balance in diets of broiler chickens has resulted in a serious distur-bance of blood acid-base balance, coupled with elevated body temperature. The body losses carbon dioxide (CO2) and bicarbon...The loss of electrolyte balance in diets of broiler chickens has resulted in a serious distur-bance of blood acid-base balance, coupled with elevated body temperature. The body losses carbon dioxide (CO2) and bicarbonate (HCO3), resulting in respiratory alkalosis or acidosis. Under tropical conditions of high environmental temperatures, the balance of electrolytes in feeds must be set much higher as to maintain equal metabolic and digestive efficiency. However, information on the ideal dietary electrolyte balance (DEB) that could effectively correct acid-base imbalance in broiler chickens under severe heat stress condition is scanty. Therefore, the effects of varying electrolyte balance in diets on haematology, blood glucose and serum inorganic elements were assessed in broiler chickens at starter (0 - 21 d) and finisher (22 - 35 d) phases, under temperature-humidity index of 24.97 - 35.19. One day-old Arbor Acre chicks (n = 300) were procured and randomly allotted to diets supplemented with potassium chloride and sodium bicarbonate, to balance monovalent ions (sodium, potassium and chloride) at 210 (T1), 240 (T2), 270 (T3), 300 (T4), 330 (T5) and 360 (T6) mEq/kg DEB, in a completely randomised design. On days 21 and 35, blood (5 mL) samples were collected from birds in each replicate whose weights were closest to the mean class weight for haematology and serum biochemical indices using standard procedures. Data were analysed using descriptive statistics and ANOVA at α = 0.05. Different levels of DEB did not significantly affect (P > 0.05) haematology and blood glucose at starter phase. However, at finisher phase, heterophil: lymphocyte of birds on 270 and 240 mEq/kg DEB were lower (P < 0.05) compared to other dietary treatments. Blood acid-base balance was relatively enhanced in birds on aggregate DEB level of 360 mEq/kg with reduced chloride ion and relatively lower incidence of hemodilution with respect to high haemoglobin levels as this level is advantageous in balancing blood acid to base ratio in broiler chickens reared under severe environmental temperatures higher than 43?C ± 5?C as against some previous opinions that did not take into consideration, the inherent dietary electrolyte balance in feedstuff, other functional mono or divalent ions, and the severity of environmental factors.展开更多
文摘[ Objective] TO further explore the mechanism of retained fetal membrane （RFM） of dairy cows in Qinghai Province. [ Methed] As many as 15 dairy cows with retained fetal placenta and 15 without retained fetal placenta were selected. The serum concentrations of eight metal ions, namely, potassium, sodium, calcium, magnesium, copper, iron, zinc and manganese at parturition and 12 h post partum were determined by atomic absorption spectrometry. The anti-oxidative indexes at parturition were determined by UV-1601 doub｜e-beam visib｜e spectrophotometer. ~=- sultl In the dairy cows with retained fetal placenta, the concentrations of calcium, magnesium, copper, zinc and manganese were decreased signif- icantly （ P 〈 0.05） ; that of iron was increased significantly （ P 〈 0.01 ） ; those of potassium and sodium did not change greatly; the activities of su- peroxide dismutase and glutathione peroxidase were decreased significantly （ P 〈 0.01 ） ; and the MDA content was increased significantly （ P 〈 0.05）. However, the concentrations of the eight metal ions and anti-oxidative indexes did not change in the dairy cows without retained fetal placen- ta, [ CondusionJ The RFM of dairy cows has some relationships with the serum concentrations of metal ions and antioxidation.
文摘In this paper is reported a new method of determining serum albumin with potentiometry. The silver ion selective electrode was used as working electrode and S. C. E as reference electrode. By controlling the ionic strength, PH and temperature constant, a good linear relationship was obtained between the cell potential and albumin concentration. This method .possessed characters-of operating simplicity, rapidity and directness. The samples could be detected directly and the results were in accordance with the values detected by classic K method.
文摘Eleven chelating agents were studied for their capabilities to mobilize the cadmium bound tp bovine serum albumin(BSA).The parameter F,which is defined as the ratio between the percentages of cadmium bound to BSA in the presence and absence of chelating agents,can be used as the criterion to evaluate the mobilizing capability of chelating agent.The F values determined experimentally lead to a mobilizing capability order:DTPA>EDTA>EGTA>NTA>TR1EN>PEN>CYS>HIS>SAThe polyaminopolycarboxylate type chelators mobilize cadmium effectively.A linear relationship was found between 1gF and lg k'CdL (conditional stability constant of the cadmium chelate).
文摘The binding mechanism of the interactions of halide ions (F–, Br– and I–) with bovine serum albumin (BSA) and hemoglobin (Hb) were studied at different temperatures, by using ion-selective electrodes. The experimental data were treated according to Klotz equation, and the number of binding sites and the binding constants were determined. The results show that the binding sites of F– on protein molecules are more than those of Br– and I–. Additionally, the number of the binding sites for halide ions on protein molecules increases with increasing temperature. This study also indicates that the binding constants for the interactions of halide ions with proteins gradually decrease as the size of halide ions and temperature increases. These behaviors were reasonably interpreted with the structural and thermodynamic factors. The thermodynamic functions at different temperatures were calculated with thermodynamic equations, and the enthalpy change for the interactions were also determined by isothermal titration calorimetry (ITC) at 298.15 K, which indicate that the interactions of halide ions with proteins are mainly electrostatic interaction.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (Nos. 2004AA603110 and 2008AA10Z227)the National Natural Science Foundation of China (No. 30490234)
文摘We evaluated the ability of juvenile Amur sturgeon (Acipenser schrenckii) to osmoregulate and grow in saltwater. Hatchery-reared juveniles (mean weight 106.8 g, 5-month old) were transferred from freshwater to 10, 20, and 25 salinity saltwater over a period of 20 d. We measured the growth, serum osmolality, ion concentrations, and Na+/K+-ATPase activity. In addition, we prepared samples of gill tissue to quantify morphological changes in gill ultrastructure. Rearing in up to 25 saltwater for 30 d had no significant effect on growth. Similarly, serum osmolality and ion concentrations were similar to levels reported in other teleosts following acclimation to saltwater. Serum osmolality and Na+, Cl- concentrations increased significantly with the initial increase in salinity. Afterwards, levels tended to stabilize and then decrease. Serum K+ levels did not change during acclimation to saltwater. Gill Na+/K+-ATPase activity increased initially as salinity was increased. However, the activity later decreased and, finally stabilized at 3.7±0.1 μmol Pi/mg·prot·h in 25 saltwater (1.6 times higher than the level in those in freshwater). In fish that were held only in freshwater, the chloride cells were located in the interlamellar regions of the filament and at the base of the lamella. Following acclimation to 25 saltwater for 30 d, the number and size of chloride cells increased significantly. Our results suggest that juvenile Amur sturgeon is able to tolerate, and grow in, relatively high concentrations of saltwater.
基金supported by the National Natural Science Foundation of China(Nos.20575007 and 30872109)
文摘In this article, a novel strong interaction by forming complex between bovine serum albumin （BSA） and copper ion was utilized for the preparation of molecular imprinted bydrogel in aqueous solution. Results show that the inclusion of copper ion in preparation can bridge the template BSA and functional monomers together and improve the imprinting effect compared to the polymer made without copper ion added. High selectivity factor and large adsorption capacity are also observed for the obtained BSA-imprinted hydrogel.
文摘The loss of electrolyte balance in diets of broiler chickens has resulted in a serious distur-bance of blood acid-base balance, coupled with elevated body temperature. The body losses carbon dioxide (CO2) and bicarbonate (HCO3), resulting in respiratory alkalosis or acidosis. Under tropical conditions of high environmental temperatures, the balance of electrolytes in feeds must be set much higher as to maintain equal metabolic and digestive efficiency. However, information on the ideal dietary electrolyte balance (DEB) that could effectively correct acid-base imbalance in broiler chickens under severe heat stress condition is scanty. Therefore, the effects of varying electrolyte balance in diets on haematology, blood glucose and serum inorganic elements were assessed in broiler chickens at starter (0 - 21 d) and finisher (22 - 35 d) phases, under temperature-humidity index of 24.97 - 35.19. One day-old Arbor Acre chicks (n = 300) were procured and randomly allotted to diets supplemented with potassium chloride and sodium bicarbonate, to balance monovalent ions (sodium, potassium and chloride) at 210 (T1), 240 (T2), 270 (T3), 300 (T4), 330 (T5) and 360 (T6) mEq/kg DEB, in a completely randomised design. On days 21 and 35, blood (5 mL) samples were collected from birds in each replicate whose weights were closest to the mean class weight for haematology and serum biochemical indices using standard procedures. Data were analysed using descriptive statistics and ANOVA at α = 0.05. Different levels of DEB did not significantly affect (P > 0.05) haematology and blood glucose at starter phase. However, at finisher phase, heterophil: lymphocyte of birds on 270 and 240 mEq/kg DEB were lower (P < 0.05) compared to other dietary treatments. Blood acid-base balance was relatively enhanced in birds on aggregate DEB level of 360 mEq/kg with reduced chloride ion and relatively lower incidence of hemodilution with respect to high haemoglobin levels as this level is advantageous in balancing blood acid to base ratio in broiler chickens reared under severe environmental temperatures higher than 43?C ± 5?C as against some previous opinions that did not take into consideration, the inherent dietary electrolyte balance in feedstuff, other functional mono or divalent ions, and the severity of environmental factors.
