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1.
J Nanosci Nanotechnol ; 20(2): 810-818, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383076

RESUMO

Porous MgO nanostructures were synthesized in large-scale by a simple solution combustion method using citric acid and glucose as the fuel. The resulting porous nanostructure powders were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), transmission electron microscopy (TEM), and N2 adsorption-desorption isotherms. The SEM and TEM images demonstrated that the type of fuel used during the combustion synthesis strongly affects the morphology and structure. The use of glucose aggregated the structure with majority particle sizes in the range 3560 nm and a surface area of 40.55 m²g-1, while the use of citric acid results in a large network structure with smaller particle sizes (30-50 nm) and a larger surface area of 53.88 m²g-1. The two samples synthesized from glucose and citric acid exhibited excellent adsorption performance for Congo red with the maximum capacity reaching 1500.98 mg g-1 and 1638.08 mg g-1, respectively. These results indicate that the porous MgO synthesized by the solution combustion is a potential candidate for the removal of pollutant dye in water.

2.
Huan Jing Ke Xue ; 38(4): 1357-1365, 2017 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965136

RESUMO

Water quality is the key problem that water management departments concern. Water quality of Beijing segment of South-to-North Water Diversion Middle Route Project is closely related to water security and social stability in Beijing. Since the connection of Beijing part in Middle Route of South-to-North Diversion Project, water quality data of Daning regulation and storage reservoir and Daning surge tank was collected, and water quality indexes including water temperature, total nitrogen, nitrate nitrogen, chloride ion, sulfate, dissolved oxygen, permanganate index, pH, ammonia nitrogen, fluorine ion and total phosphorus, were monitored monthly. With variance analysis, water quality difference among different water sources of the South-to-North Water Diversion of Middle Route was analyzed. With factor analysis method, the water quality risk factors of Daning regulation and storage reservoir and Daning surge tank were identified. The results were as following, water from Hebei province had higher contents of nitrate nitrogen, total nitrogen, fluorine ion, chloride ion and sulfate than those of water from Danjiangkou reservoir, but the water quality was not as good as that from Danjiangkou reservoir. LSD difference test results showed that the dissolved oxygen, nitrate nitrogen and total nitrogen of the water from Hebei province had significant differences (P<0.05) between flood season and non-flood season, there was significant difference (P<0.05) in pH of water from Danjiangkou reservoir between flood season and non-flood season, and the water quality of Danjiangkou reservoir was more stable than water from Heibei province. No matter in flood season or non-flood season, there were no significant differences (P<0.05) in pH, dissolved oxygen, permanganate index, total phosphorus and ammonia nitrogen between the water from Danjiangkou reservoir and Heibei province, but there were significant differences (P<0.05) in nitrate nitrogen, total nitrogen, fluorine ion and sulfate ion and chloride ion. Contents of Nitrate nitrogen, total nitrogen, sulfate and chloride ion in 2015 (the mixture of water from Hebei province and Danjiangkou reservoir) in Daning regulation and storage reservoir were lower than those in 2012-2014 (water from Hebei province), and the water from Danjiangkou reservoir played a key role in dilution and adjustment of the water from Hebei province in Daning regulation and storage reservoir. The water quality differences test results between 2012-2014 and 2015 showed that there were significant differences (P<0.05) in the nitrate nitrogen, total nitrogen, fluorine ion, sulfate and chloride ion both in flood season and non-flood season, and the water quality of 2015 was better than that of 2012~2014 in non-flood season, but the differences of pH, dissolved oxygen, permanganate index, total phosphorus, ammonia nitrogen were not obvious (P<0.05). The difference test results between Daning regulation and storage reservoir and Daning surge tank showed that Permanganate index, total nitrogen, fluorine ion, sulfate and chloride ion had significant differences (P<0.05) both in flood season and non-flood season, and the contents of permanganate index, fluorine ion, sulfate and chloride ions in Daning regulation and storage reservoir were higher than those in Daning surge tank. The factor analysis results indicated that water quality potential risk factors both in Daning regulation and storage reservoir and Daning surge tank were mainly nitrogen, including ammonia nitrogen, nitrate nitrogen and total nitrogen, and potential risk factors also included total phosphorus in Daning regulation and storage reservoir.

3.
Gene ; 595(1): 83-91, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27693372

RESUMO

MicroRNAs (miRNAs) are a group of small RNAs involved in various biological processes through negative regulation of mRNAs at the post-transcriptional level. The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the most serious and destructive insect pests of rice. In the present study, two small RNA libraries of virulent N. lugens populations (Biotype I survives on susceptive rice variety TN1 and Biotype Y survives on moderately resistant rice variety YHY15) were constructed and sequenced using the high-throughput sequencing technology in order to identify the relationship between miRNAs of N.lugens and adaptation of BPH pests to rice resistance. In total 15,758,632 and 11,442,592 reads, corresponding to 3,144,026 and 2,550,049 unique sequences, were obtained in the two libraries (BPH-TN1 and BPH-YHY15 libraries), respectively. A total of 41 potential novel miRNAs were predicted in the two libraries, and 26 miRNAs showed significantly differential expression between two libraries. All miRNAs were significantly up-regulated in the BPH-TN1 library. Target genes likely regulated by these differentially expressed miRNAs were predicted using computational prediction. The functional annotation of target genes performed by Gene Ontology enrichment (GO) and Kyoto Encyclopedia of Genes and Genomes pathway analysis (KEGG) indicated that a majority of differential miRNAs were involved in "Metabolism" pathway. These results provided an understanding of the role of miRNAs in BPH to adaptability of BPH on rice resistance, and will be useful in developing new control strategies for host defense against BPH.


Assuntos
Adaptação Fisiológica/fisiologia , Regulação da Expressão Gênica/fisiologia , Hemípteros/metabolismo , MicroRNAs/biossíntese , Transcriptoma/fisiologia , Animais , Perfilação da Expressão Gênica , Hemípteros/genética , MicroRNAs/genética
4.
Wei Sheng Yan Jiu ; 44(4): 559-64, 569, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26454951

RESUMO

OBJECTIVE: To explore the relationship of left-behind children's mental health, coping style and personality, and analyze mediating effect of self-efficacy. METHODS: A total of 585 left-behind children were evaluated by questionnaires of MHT, EPQ, WCSQ and GSES. RESULT: Left-behind children's lonely tendency detection rate (6.3%) was significantly higher than their counterparts (χ2 = 4.225, P < 0.05). The subscales of MHT were positively related with remorse, fantasy, retreat (P < 0.01), but were negatively related with solve the problem, rationalization, self-efficacy. The analysis showed that self-efficacy had mediating effect affection. The structural modeling fitted the data well (χ2/df = 6.840, GFI = 0.972, AGFI = 0.918, NFI = 0.923, CFI = 0.962, RMSEA = 0.044). CONCLUSION: Personality has direct effect on the prediction of left-behind children's mental health. Self-efficacy has mediating effect affection on MHT and personality.


Assuntos
Adaptação Psicológica , Saúde Mental , Criança , Humanos , Personalidade , Autoeficácia , Inquéritos e Questionários
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 39(5): 477-82, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-24921393

RESUMO

OBJECTIVE: To determine the influence of stress on myocardial apoptosis in ischemic preconditioning group (IPC). METHODS: Twenty-four Japanese white rabbits were randomly divided into 4 groups (n=6): an etomidate group (the Etom group) of depressed stress established by intravenous etomidate, an IPC group, an ischemic reperfusion group (the IR group) and a methylprednisolone group (the MP group). Myocardial apoptosis was examined by DNA-laddering, in situ nick-end labeling (TUNEL) and Hoechst dyeing. RESULTS: The DNA ladder increased in the Etom group. The percentage of apoptosis by TUNEL method was 1.7%±0.2% in the IPC group, 2.3%±0.8% in the MP group, 3.8%±1.3% in the IR group and 3.0%±0.4% in the Etom group. Hoechst dying was 4.1%±0.9% in the IPC group, 3.5%±0.4% in the MP group, 6.2%±1.6% in the IR group and 7.6%±0.4% in the Etom group. There was significant difference between the IPC group and the Etom group or IR group, and also between the MP group and the IR group. CONCLUSION: A depressed stress response impairs the inhibition on myocardial apoptosis in ischemic preconditioning. Methylprednisolone may inhibit myocardial apoptosis.


Assuntos
Apoptose , Precondicionamento Isquêmico Miocárdico , Precondicionamento Isquêmico , Metilprednisolona/farmacologia , Miocárdio/patologia , Animais , Etomidato/farmacologia , Coração/efeitos dos fármacos , Coelhos
6.
J Huazhong Univ Sci Technolog Med Sci ; 34(2): 220-224, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24710936

RESUMO

The purpose of this study was to determine the combined effect of transmyocardial laser revascularization (TMLR) and the implantation of endothelial progenitor cells (EPCs) on cardiac function of ischemic hearts in canines. The left anterior descending artery (LAD) was occluded to establish the canine model of acute myocardial infarct (AMI). Four weeks later, the animals were randomly divided into four groups: TMLR group, in which transmyocardial laser-induced channels were established at the ischemic region; EPCs+TMLR group, in which EPCs were locally transplanted into laser-induced channels at the ischemic region; EPCs group, in which the EPCs were injected into the ischemic region; control group, in which the AMI animals received neither TMLR nor EPCs. The peripheral blood (50 mL) was sampled in all groups. Mononuclear cells from the peripheral blood were separated and cultured to obtain spindle-shaped attaching (AT) cells in vitro. AT cells were labeled with 1, 1'-dioctadecyl-1 to 3,3, 3',3'-tetramethyl-indocarbocyanine perchlorate (DiI) before injecting into the laser-induced channels or ischemic region. Four weeks after the first operation, TMLR was performed in the TMLR group and EPCs+TMLR group, and at the same time, the EPCs originating from the AT cells were mixed with calcium alginate (CA). Then the EPCs-CA composites were implanted into myocardial channels induced by laser in the EPCs+TMLR group, and into the myocardial infarct area in the EPCs group. All dogs underwent echocardiography at second month after LAD occlusion. Finally the samples of myocardium around the LAD were subjected to histochemical and immunohistologic examinations. The results showed there was no significant difference in the diameter of left atrium and ventricle before treatment among all groups (P>0.05). Eight weeks after modeling, the regional contractility in the LAD territory in the EPCs+TMLR group was increased as compared with control group and TMLR group, but there was no significant difference between control group and TMLR group. Neoangiogenesis was observed in the EPCs+TMLR group, and the fibrosis was seen in the TMLR group. There was no significant difference in neoangiogenesis around the channels induced by laser among EPCs+TMLR, EPCs and TMLR groups. It was concluded that TMLR combined with EPCs could improve the regional and global cardiac function in AMI, and augment neovascularizaiton in channels of ischemic myocardium induced by laser.


Assuntos
Isquemia Miocárdica/terapia , Transplante de Células-Tronco/métodos , Células-Tronco , Revascularização Transmiocárdica a Laser/métodos , Animais , Circulação Coronária , Vasos Coronários/patologia , Vasos Coronários/cirurgia , Cães , Humanos , Contração Muscular/fisiologia , Isquemia Miocárdica/patologia , Miocárdio/patologia , Neovascularização Fisiológica/fisiologia
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 38(8): 804-8, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23981998

RESUMO

OBJECTIVE: To determine the role of stress in myocardial protection of ischemic preconditioning (IPC). METHODS: Thirty rabbits were randomly divided into an IPC group, an etomidate (Etom) group, an ischemic/reperfusion (IR) group, a methylprednisolone (MP) group and a sham group. The ratio of infarction size versus risk area (infarct/risk) was calculated. The elevations of the serum creatine kinase (CK) activity and cardiac troponin I (cTnI) concentrations as well as the serum cortisol concentrations were measured. RESULTS: The percentages of infarct/risk in the IPC group, the MP group, the IR group, and the Etom group were (5.86±2.81)%, (11.28±3.62)%, (26.79±4.53)%, and (18.19±3.72)%, respectively. The elevations of the serum CK activity in the IPC group, the MP group, the IR group, and the Etom group were (255±89), (314±160), (855±371), and (768±404) U/L, respectively. The elevations of serum cTnI concentrations in the IPC group, the MP group, the IR group, and the Etom group were (3.6±0.6),(6.1±2.2), (8.1±3.6), and (6.4±1.6) µg/L, respectively. Those indicators among the groups were significantly different (P<0.05). Cortisol reaction was markedly diminished in the Etom group. CONCLUSION: A blunted cortisol reaction can markedly reduce the benefit of IPC while methylprednisolone shows cardioprotective effects, suggesting that stress might be involved in the myocardial protection of IPC.


Assuntos
Precondicionamento Isquêmico Miocárdico , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Estresse Fisiológico , Animais , Etomidato/farmacologia , Feminino , Hidrocortisona/sangue , Masculino , Coelhos
12.
Huan Jing Ke Xue ; 34(3): 882-91, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23745390

RESUMO

One of the key techniques in establishing and implementing TMDL (total maximum daily load) is to utilize hydrological model to quantify non-point source pollutant loads, establish BMPs scenarios, reduce non-point source pollutant loads. Non-point source pollutant loads under different years (wet, normal and dry year) were estimated by using SWAT model in the Zhangweinan River basin, spatial distribution characteristics of non-point source pollutant loads were analyzed on the basis of the simulation result. During wet years, total nitrogen (TN) and total phosphorus (TP) accounted for 0.07% and 27.24% of the total non-point source pollutant loads, respectively. Spatially, agricultural and residential land with steep slope are the regions that contribute more non-point source pollutant loads in the basin. Compared to non-point source pollutant loads with those during the baseline period, 47 BMPs scenarios were set to simulate the reduction efficiency of different BMPs scenarios for 5 kinds of pollutants (organic nitrogen, organic phosphorus, nitrate nitrogen, dissolved phosphorus and mineral phosphorus) in 8 prior controlled subbasins. Constructing vegetation type ditch was optimized as the best measure to reduce TN and TP by comparing cost-effective relationship among different BMPs scenarios, and the costs of unit pollutant reduction are 16.11-151.28 yuan x kg(-1) for TN, and 100-862.77 yuan x kg(-1) for TP, which is the most cost-effective measure among the 47 BMPs scenarios. The results could provide a scientific basis and technical support for environmental protection and sustainable utilization of water resources in the Zhangweinan River basin.


Assuntos
Monitoramento Ambiental , Chuva , Poluentes Químicos da Água/análise , Poluição da Água/estatística & dados numéricos , China , Análise Custo-Benefício , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Nitrogênio/análise , Fósforo/análise , Rios , Movimentos da Água , Poluição da Água/economia , Poluição da Água/prevenção & controle
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 38(3): 279-82, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23545833

RESUMO

OBJECTIVE: To determine the use of septal plication with Dor or Cooley procedure for post infarction anterior and anterior-septal aneurysm of the left ventricle. METHODS: A total of 23 patients with post infarction anterior and anterior-septal aneurysm of the left ventricle underwent septal plication and Dor or Cooley procedure along with coronary artery bypass grafting concomitantly. Data of NYHA grading, left ventricular end diastolic volume index (LVEDVI), left ventricular end systolic volume index (LVESVI) and left ventricular ejection fraction (LVEF) were recorded before the surgery, before discharge and 3 months after the surgery. RESULTS: Compared with the preoperative data, the NYHA grading before the discharge and 3 months after the surgery improved from 3.21 ± 0.62 to 1.72 ± 0.31 and 1.57 ± 0.23(P<0.05); LVEDVI decreased from (102.31 ± 18.71) mL/m² to (62.11 ± 6.21) mL/m² and (54.63 ± 4.54) mL/m² (P<0.05); LVESVI decreased from (69.32 ± 17.48) mL/m² to (30.23 ± 3.25)mL/m² and (28.34 ± 3.12) mL/m²; while LVEF increased from (32.92 ± 8.12)% to (48.78 ± 4.51)% and (50.52 ± 4.68)% (P<0.05), respectively. CONCLUSION: Ventricular septal plication combined with Dor or Cooley procedure can remarkably improve the left heart function in patients with post infarction ventricular aneurysm.


Assuntos
Aneurisma Cardíaco/cirurgia , Infarto do Miocárdio/complicações , Função Ventricular Esquerda/fisiologia , Septo Interventricular/cirurgia , Idoso , Ponte de Artéria Coronária/métodos , Feminino , Aneurisma Cardíaco/etiologia , Ventrículos do Coração/patologia , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
14.
Huan Jing Ke Xue ; 33(2): 359-69, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22509568

RESUMO

In this study, several statistical methods including cluster analysis, seasonal Kendall test, factor analysis/principal component analysis and principal component regression were used to evaluate the spatiotemporal variation of water quality and identify the sources of water pollution in the Zhangweinan River basin. Results of spatial cluster analysis and principal component analysis indicated that the Zhangweinan River basin can be classified into two regions. One is the Zhang River upstream located in the northwest of the Zhangweinan River basin where water quality is good. The other one covers the Wei River and eastern plain of the Zhangweinan River basin, where water is seriously polluted. In this region, pollutants from point sources flow into the river and the water quality changes greatly. Results of temporal cluster analysis and seasonal Kendall test indicated that the study periods may be classified into three periods and two different trends were detected during the period of 2002-2009. The first period was the year of 2002-2003, during which water quality had deteriorated and serious pollution was observed in the Wei river basin and eastern plain of the Zhangweinan River basin. The second period was the year of 2004-2006, during which water quality became better. The year of 2007-2009 is the third period, during which water quality had been improved greatly. Despite that water quality in the Zhangweinan River basin had been improved during the period of 2004-2009, the water quality in the Wei River (southwestern part of the basin), the Wei Canal River and the Zhangweixin River (eastern plain of the basin) is still poor. Principal component analysis and multi-linear regression of the absolute principal component scores showed that the main pollutants of the Zhangweinan River basin came from point source discharge such as heavy industrial wastewater, municipal sewage, chemical industries wasterwater and mine drainage in upstream. Non-point source pollution such as agricultural pollution and runoff pollution caused by heavy rainfalls also showed considerable impact on water quality in the Zhangweinan River basin during flood seasons. These results provide useful information for better pollution control strategies in the Zhangweinan River basin.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , China , Análise por Conglomerados , Análise de Componente Principal , Rios , Poluição Química da Água/prevenção & controle
15.
Huan Jing Ke Xue ; 32(3): 632-40, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21634157

RESUMO

Riparian zone hydrology is dominated by shallow groundwater with complex interactions between groundwater and surface water. There are obvious relations of discharge and recharge between groundwater and surface water. Flood is an important hydrological incident that affects groundwater quality in riparian zone. By observing variations of physical and chemical groundwater indicators in riparian zone at the Kouma section of the Yellow River Wetland, especially those took place in the period of regulation for water and sediment at the Xiaolangdi Reservoir, relationship between the groundwater quality in riparian zone and the flood water quality in the river is studied. Results show that, affected by the river and pond water, the highest point of groundwater temperature is near the pond in spring, and near the river in winter; and regulation for water and sediment at the Xiaolangdi Reservoir also affects groundwater temperature in riparian zone, which reaches its maximum at 100 m far from the river bank. There exists a strong zone of nitrification area at 50 m from the river bank, and in this area, the groundwater pH value is lower by 0.2 to 0.4 unit than that of the other regions, with great annual varieties. The turbidity of groundwater is affected by irrigation, which is more obvious than other indicators of groundwater. The turbidity of groundwater and river water increase rapidly during the early phase of flood retreat, and slope stability of river bank is the initial impact of the soil erosion of river bank. Conductivity, chloride and sulfate data show that the range of 50-200 m in riparian wetland is a very important salt accumulation zone, and the width of salt accumulation zone changes with seasons, and this area is also a very important zone of sulfur reduction. The quality of groundwater at 200 m from the river bank is also significantly affected by floods. Physical and chemical indicators of water change strongly in this area. The result indicates that there is a very close relationship between groundwater and surface water, and it is the typical land and water ecotone between groundwater of riparian zone and the river. Rational protection for this region is critical for the conservation of water quality both in the river and groundwater.


Assuntos
Inundações , Água Doce/análise , Movimentos da Água , Poluição da Água/análise , Áreas Alagadas , Fenômenos Químicos , China , Água Doce/química , Rios/química
16.
Huan Jing Ke Xue ; 32(2): 362-7, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21528555

RESUMO

The development and degradation processes of riparian wetlands are significantly affected by river hydrological processes. By observing the variation of groundwater levels in riparian wetlands at the Kouma section of the Yellow River Wetland, especially that during the period of regulation for water and sediment at the Xiaolangdi Reservoir, relationship between groundwater level in riparian wetlands and flood water level in the river is studied. The results show that groundwater level in riparian wetlands is significantly affected by water level in the river investigated. There is a negative exponential relationship between groundwater level and the distance between wells and river. The correlation coefficient shows the maximum (R2 > 0.98) during the period of regulation for water and sediment. Affected by the cultivation system in the flooding area, distance between monitoring wells and river bank, water level in the river variation of groundwater level in the wetland changed greatly. In artificial wetland, which is far from the river, the inter-annual variation in groundwater levels show a " (see symbol)" shape, while in the farmland, which is close to the river, the inter-annual variation of groundwater levels show a big peak. The groundwater level 400 m from the river is affected by flood events obviously, that in the area which is less than 200 m from the river is significantly affected by flood events in the area which is especially less than that in the area that is less than 100 m from the river, the groundwater level is affected by flood events intensively. The result indicated that there was a very close relationship between groundwater and surface water, and it was the hydrological ecotone between groundwater of riparian wetlands and the river. It is very important that rational protection for this region (very important for the area which is less than 100 m from the river, important for the area that is between 100 m and 200 m from the river) is critical for the conservation of water quality in the river and groundwater quality.


Assuntos
Inundações , Água Doce/análise , Movimentos da Água , Abastecimento de Água/análise , Áreas Alagadas , China , Água Doce/química , Rios , Poluição da Água/prevenção & controle
17.
J Environ Sci (China) ; 21(7): 933-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19862959

RESUMO

Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Using the field experiment method and an isotope tracing technique, the agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetland was studied in the Kouma Section of the Yellow River. The results showed that the retention of agricultural non-point nitrogen pollution by riparian wetland soil occurs mainly in top 0-10 cm layer. The amount of nitrogen retained by surface soils associated with three types of vegetation are 0.045 mg/g for Phragmites communis Trin Linn, 0.036 mg/g for Scirpus triqueter Linn, and 0.032 mg/g for Typha angustifolia Linn, which account for 59.21%, 56.25%, and 56.14% of the total nitrogen interception, respectively. Exogenous nitrogen in 0-10 cm soil layer changes more quickly than in other layers. One month after adding K(15)NO3 to the tested vegetation, nitrogen content was 77.78% for P. communis Trin, 68.75% for T. angustifolia, and 8.33% for S. triqueter in the surface soil. After three months, nitrogen content was 93.33% for P. communis Trin, 72.22% for S. triqueter, and 37.50% for T. Angustifolia. There are large differences among vegetation communities respecting to purification of agricultural non-point nitrogen pollution. The nitrogen uptake amount decreases in the sequence: new shoots of P. communis Trin (9.731 mg/g) > old P. communis Trin (4.939 mg/g) > S. triqueter (0.620 mg/g) > T. angustifolia (0.186 mg/g). Observations indicated that the presence of riparian wetlands as buffers on and adjacent to stream banks could be recommended to control agricultural non-point pollution.


Assuntos
Agricultura , Poluição Ambiental/análise , Nitrogênio/análise , Áreas Alagadas , China , Ecossistema , Monitoramento Ambiental , Rios
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(5): 667-70, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17062927

RESUMO

OBJECTIVE: To determine the effects of reacting cortisol on ischemic preconditioning (IPC). METHODS: Thirty rabbits were randomized into ischemic preconditioning (IPC) group, etomidate (Etom) group, ischemic/reperfusion (IR) group, methylprednisolone (MP) group and a control group. The ratios of infarction size versus risk area (Infarct/Risk) were calculated. The elevations of serum CK activity and cTnI concentrations as well as serum cortisol concentrations were measured. RESULTS: The ratios of Infarct/Risk were 5.9%+/-2.8% for IPC, 11.3%+/-3.6% for Etom, 26.8%+/-4.5% for IR and 18.2%+/-3.7% for MP. The elevations of serum CK activity (U/L) were 255+/-89 for IPC, 314+/-160 for Etom, 855+/-371 for IR and 768+/-404 for MP, the elevations of serum cTnI concentrations (microg/L) were 3.6+/-0.6 for IPC, 5.9+/-2.0 for Etom, 8.1+/-3.6 for IR and 6.1+/-2.3 for MP. Those indicators among groups are all significantly different (P<0.01). Cortisol reacting was markedly diminished in Etom group. CONCLUSION: A blunted cortisol reaction can markedly undermine the benefit of ischemic preconditioning, methylprednisolone show a certain myocardial protection. Cortisol may play an important role in the IPC process.


Assuntos
Creatina Quinase Forma MB/sangue , Precondicionamento Isquêmico Miocárdico , Metilprednisolona/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Etomidato/uso terapêutico , Feminino , Masculino , Traumatismo por Reperfusão Miocárdica/sangue , Coelhos , Distribuição Aleatória
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