RESUMEN

Anthropogenic nitrogen (N) addition has increased soil nutrient availability, thereby affecting ecosystem processes and functions in N-limited ecosystems. Long-term N addition decreases plant biodiversity, but the effects of short-term N addition on soil microbial community is poorly understood. The present study examined the impacts of short-term N addition (NH4NO3) on these factors in a sandy grassland and semi-fixed sandy land in the Horqin Sandy Land. We measured the responses of soil microbial biomass C and N; on soil ß-1,4-glucosidase (BG) and ß-1,4-N-acetylglucosaminidase (NAG) activity; and soil microflora characteristics to N additions gradient with 0 (control), 5 (N5), 10 (N10), and 15 (N15) g N m-2 yr-1. The soil microbial biomass indices, NAG activity, and soil microflora characteristics did not differ significantly among the N levels, and there was no difference at the two sites. The competition for N between plants and soil microbes was not eliminated by short-term N addition due to the low soil nutrient and moisture contents, and the relationships among the original soil microbes did not change. However, N addition increased BG activity in the N5 and N10 additions in the sandy grassland, and in the N5, N10, and N15 additions in the semi-fixed sandy land. This may be due to increased accumulation and fixation of plant litter into soils in response to N addition, leading to increased microbial demand for a C source and increased soil BG activity. Future research should explore the relationships between soil microbial community and N addition at the two sites.

Asunto(s)

Microbiota/efectos de los fármacos , Nitrógeno/farmacología , Microbiología del Suelo , Suelo/química , Acetilglucosaminidasa/análisis , Proteínas Bacterianas/análisis , Biomasa , Fertilizantes , Nitrógeno/análisis , beta-Glucosidasa/análisis

RESUMEN

Objective To compare the Modified Early Warning Score(MEWS),blood glucose value score and the two scores combined with the ability to predict the prognosis of patients with acute complication of diabetes mellitus,and to explore the most suitable assessment tools. Methods 419 patients with acute complica-tions were collected in diabetic mellitus. To put the admission time as the inital observation point,MEWS score, blood glucose value score and MEWS combined with blood glucose value were assessed and compared between the time point of admission and discharge by ROC curve.Results Using death as a prediction index,MEWS score of subjects operating characteristic area under the curve of AUCROC was 0.875 and the optimal cut-off value of was over 4 in the sensitivity of 78.43%,specificity of 85.60%,the positive predictive valueof 43.01% and the negative predictive value of 96.63% independently. The average score of blood glucose area under ROC curve AUCROC was 0.681 and the optimal cut-off value was 2 in the sensitivity of 50.98%,the specificity of 85.33% the positive predictive value of 73.4% and negative predictive value of 67.5% respectively. Two scores combined with area under ROC curve AUCROCwas 0.982,and the optimal cut-off value was over 7 in the sensitivity of 94.12%,the specificity of 95.65%,the positive predictive value of 75% and the negative predictive value of 99.15% individually. Conclusion For predicting the prognosis of patients with acute complications of diabetes,the combined scores are better than the pure MEWS score and blood glucose value.It is worth of clinical application.

RESUMEN

Objective To evaluate efficiency of brain metastases tumor using X-knife under farctionational stereotactie radiotherapy (FSRT) combine with whole brain radiotherapy (WBRT). Methods Retrospective comparing 51 patients treated by FSRT plus WBRT (FSRT + WBRT group) with 35 patients treated by WBRT alone (WBRT group) on the effecting rate and survival rate. Results The completeness response rate was 49 % and 26 % (P < 0.05) in FSRT + WBRT and WBRT groups, respectively. The effecting rate was 80 % and 71 % (P 0.05) in FSRT + WBRT and WBRT groups, respectively. The middle survival time was (11.0 ± 1.5) months and (6.5 ± 0.5) months (P < 0.05) in FSRT + WBRT and WBRT groups, respeetivley. The 0.5-, 1.0- and 1.5-years survival rate was 63 % and 41 % (P 0.05), 51 % and 23 % (P 0.05) and 24 % and 9 % (P < 0.05) in FSRT + WBRT and WBRT groups, respectively. Conclusions The method with FSRT plus WBRT in the treatment of brain metastases tumor is safe and relieved focal symptom of patients quickly with lesser injury on normal tissue and the survival time be prolonged, it has better therapeutic effects than WBRT alone for treating brain metastases tumor.