A flock of AA breed chickens were reared in peterstme brood-vait chamber using high energy pelleted feed, at 14 days of age, 400 birds were separated into 3 groups randomly as follows:100 birds were exposed to normal ...A flock of AA breed chickens were reared in peterstme brood-vait chamber using high energy pelleted feed, at 14 days of age, 400 birds were separated into 3 groups randomly as follows:100 birds were exposed to normal ambient temperature (20℃) as control group, 150 birds were exposed to low ambient temperature (11℃) in order to induce ascites as treatment I group, another 100 birds were also exposed to low ambient temperature (11℃) and fed the diets containing 1% L-arginine for ascitic prophylactic treatment as treatment I group. The blood samples were collected on 3, 4, 5, 6, 7 wk, respectively, to measure the contents of plasma endothelin (ET-1), angiotensin Ⅱ(Ang Ⅱ) and cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). The results indicated that the contents of cAMP, cGMP, AngⅡ and the ratio of cAMP/cGMP in treatment I and ascitic broilers were higher than that of correspondent control group(P<0.01, P<0.05), ET-1 of preascitic broilers were higher than that of control group(P<0. 05), while there were insignificant differences with later ascitic broilers, the contents of cAMP and cGMP in treatment Ⅱ were higher than treatment I and control group(P<0.01, P<0.05), whereas, the ratio of cAMP/ cGMP and the contents of Ang Ⅱ were gradually decreased than that of control group (P<0. 05), the contents of ET-1 were not changed. By further analysis, the increased plasma Ang I at low ambient temperature condition in broilers made endothelium cell secretion of increased ET-1, cAMP, cGMP and decreased NO. So low temperature accelarated ascites syndrome in broilers. Supplemented L-arginine can decrease ET-1, cAMP and cAMP/cGMP. It is concluded that cAMP mediated pulmonary hypertension syndrome in broilers.展开更多
Under the influence of the rapid development of modern industry, the market demand for energy is increasing day by day, which makes the existing energy reserves decrease day by day. At present, the world's power e...Under the influence of the rapid development of modern industry, the market demand for energy is increasing day by day, which makes the existing energy reserves decrease day by day. At present, the world's power energy is mostly dependent on thermal power generation. However, the polluted dust and gas released from it will directly affect human health and the natural environment, which is contrary to the concept of sustainable development. Under this background, wind energy has attracted the attention of the energy market due to its renewable and pollution-free advantages. Especially under the background of increasingly mature wind power generation technology, the application rate of wind turbines has been gradually increased, effectively easing the pressure on electricity consumption in the market. In this regard, this paper will analyze the principle of wind power generation and the key points of wind power generation technology, aiming at promoting the promotion of economic and social benefits of wind power generation by improving the control degree of wind power application.展开更多
In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjian...In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjiang Province, China, and were randomly devided into 4 groups with 5 for each. ① supplemented with 0.7 mg·kg -1 iodine(potassium iodine), ② supplemented with 0.2 mg·kg -1 selenium (sodium selenite), ③ supplemented with 0.7 mg·kg -1 iodine(potassium Iodine) plus 0.2 mg·kg -1 selenium (sodium selenite) per day for 30 days, respectively. ④control group. The whole blood glutathione peroxidase (GSH-px) and catalase (CAT) activities, free radicals (FR) concentration, erythrocyte superoxide dismutase (SOD) activity and molonaldehyde (MDA) concentration, the serum triiodothyronine (T 3)、thyroxine (T 4) and thyrotropin (TSH) were determined on the day of supplementation day-0 and day-30, respectively. It was showed that average iodine concentration in drinking water and diet were 3.82 μg·L -1 and 0.285mg·kg -1 , respectively, Diet selenium was 0.0498mg·kg -1 , Serum protein bound iodine(PBI) was 7.02 μg·100 mL, Blood selenium was 0.14 mg·L -1 , the schoolchildren′s goiter was 21.8%. It indicated that iodine and selenium were deficient in the investigated area. Whole blood GSH-px and CAT activities and serum T 3 concentration were significantly higher (P< 0.01 ), FR concentration and serum TSH were significantly lower(P<0.01) in the first three groups than that of the control, T 4 content in the first group was higher(P<0.05), T 4 was also higher (P>0.05) in the second group. and lower in the third group. The SOD and MDA in erythrocyte were not changed during the experimental period, The results also showed that GSH-px and CAT activities were increased, and FR decreased oberviously in the third group more than the other two groups, In addition, Thyroid hormone metabolism was more coincided with the physiologic status in the third group. the iodine and the selenium played an important role in the pathologic process of free radical metabolic disorder. selenium not only had the function of antioxidation by derectly scavenging free radicals, but also affected through GSH-px and CAT activities. iodine deficiency results in the Goiter, selenium deficiency aggravated iodine deficiency, Iodine and the selenium were dependent and restrained each other in the course of free radicals and thyroid hormone metabolism with a synergistic state.展开更多
文摘A flock of AA breed chickens were reared in peterstme brood-vait chamber using high energy pelleted feed, at 14 days of age, 400 birds were separated into 3 groups randomly as follows:100 birds were exposed to normal ambient temperature (20℃) as control group, 150 birds were exposed to low ambient temperature (11℃) in order to induce ascites as treatment I group, another 100 birds were also exposed to low ambient temperature (11℃) and fed the diets containing 1% L-arginine for ascitic prophylactic treatment as treatment I group. The blood samples were collected on 3, 4, 5, 6, 7 wk, respectively, to measure the contents of plasma endothelin (ET-1), angiotensin Ⅱ(Ang Ⅱ) and cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). The results indicated that the contents of cAMP, cGMP, AngⅡ and the ratio of cAMP/cGMP in treatment I and ascitic broilers were higher than that of correspondent control group(P<0.01, P<0.05), ET-1 of preascitic broilers were higher than that of control group(P<0. 05), while there were insignificant differences with later ascitic broilers, the contents of cAMP and cGMP in treatment Ⅱ were higher than treatment I and control group(P<0.01, P<0.05), whereas, the ratio of cAMP/ cGMP and the contents of Ang Ⅱ were gradually decreased than that of control group (P<0. 05), the contents of ET-1 were not changed. By further analysis, the increased plasma Ang I at low ambient temperature condition in broilers made endothelium cell secretion of increased ET-1, cAMP, cGMP and decreased NO. So low temperature accelarated ascites syndrome in broilers. Supplemented L-arginine can decrease ET-1, cAMP and cAMP/cGMP. It is concluded that cAMP mediated pulmonary hypertension syndrome in broilers.
文摘Under the influence of the rapid development of modern industry, the market demand for energy is increasing day by day, which makes the existing energy reserves decrease day by day. At present, the world's power energy is mostly dependent on thermal power generation. However, the polluted dust and gas released from it will directly affect human health and the natural environment, which is contrary to the concept of sustainable development. Under this background, wind energy has attracted the attention of the energy market due to its renewable and pollution-free advantages. Especially under the background of increasingly mature wind power generation technology, the application rate of wind turbines has been gradually increased, effectively easing the pressure on electricity consumption in the market. In this regard, this paper will analyze the principle of wind power generation and the key points of wind power generation technology, aiming at promoting the promotion of economic and social benefits of wind power generation by improving the control degree of wind power application.
文摘In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjiang Province, China, and were randomly devided into 4 groups with 5 for each. ① supplemented with 0.7 mg·kg -1 iodine(potassium iodine), ② supplemented with 0.2 mg·kg -1 selenium (sodium selenite), ③ supplemented with 0.7 mg·kg -1 iodine(potassium Iodine) plus 0.2 mg·kg -1 selenium (sodium selenite) per day for 30 days, respectively. ④control group. The whole blood glutathione peroxidase (GSH-px) and catalase (CAT) activities, free radicals (FR) concentration, erythrocyte superoxide dismutase (SOD) activity and molonaldehyde (MDA) concentration, the serum triiodothyronine (T 3)、thyroxine (T 4) and thyrotropin (TSH) were determined on the day of supplementation day-0 and day-30, respectively. It was showed that average iodine concentration in drinking water and diet were 3.82 μg·L -1 and 0.285mg·kg -1 , respectively, Diet selenium was 0.0498mg·kg -1 , Serum protein bound iodine(PBI) was 7.02 μg·100 mL, Blood selenium was 0.14 mg·L -1 , the schoolchildren′s goiter was 21.8%. It indicated that iodine and selenium were deficient in the investigated area. Whole blood GSH-px and CAT activities and serum T 3 concentration were significantly higher (P< 0.01 ), FR concentration and serum TSH were significantly lower(P<0.01) in the first three groups than that of the control, T 4 content in the first group was higher(P<0.05), T 4 was also higher (P>0.05) in the second group. and lower in the third group. The SOD and MDA in erythrocyte were not changed during the experimental period, The results also showed that GSH-px and CAT activities were increased, and FR decreased oberviously in the third group more than the other two groups, In addition, Thyroid hormone metabolism was more coincided with the physiologic status in the third group. the iodine and the selenium played an important role in the pathologic process of free radical metabolic disorder. selenium not only had the function of antioxidation by derectly scavenging free radicals, but also affected through GSH-px and CAT activities. iodine deficiency results in the Goiter, selenium deficiency aggravated iodine deficiency, Iodine and the selenium were dependent and restrained each other in the course of free radicals and thyroid hormone metabolism with a synergistic state.
