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1.
J Environ Manage ; 333: 117440, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36758407

RESUMO

One under-studied microelement, manganese (Mn), due to its potential to considerably interact, and limit labile, and moderately-labile soil phosphorus (P) pools, was studied in Nanchang (NC), and Qiyang (QY) under paddy conditions. The Hedley's P sequential fractionation procedure was utilized to extract, and quantify various P fractions at both surface (0-20 cm) and subsurface (20-40 cm) layers. Unfertilized control (CK), nitrogen, phosphorus, and potassium (NPK), and NPK amended with animal manure (NPKM) were used as treatments. From both sites, the manure amended fertilizer (NPKM) compared to chemical NPK formed higher proportions of macro-aggregates (>2 and 2-0.25 mm) in both layers. Total P (TP) values of 842.1 (>2 mm), and 744.4 mg kg-1 (2-0.25 mm) from NC, and QY, respectively were accumulated by NPKM compared to NPK, and CK. Total P values of 806.4, and 350.4 mg kg-1 in the >2 mm aggregate size, respectively for NC, and QY were observed in the subsurface layer. Inorganic moderately labile P (NaOH-Pi) was the dominant fraction under all fertilizer treatments. Concentrations of 232.3 (<0.053 mm), and 202.1 mg kg-1 (0.25-0.053 mm) of NaOH-Pi were accumulated by NPKM, respectively for NC, and QY in the surface layer. In the subsurface layer, concentrations of NaOH-Pi (217.5 mg kg-1; <0.053 mm) from NC, and residual-P (57.3 mg kg-1; >2 mm) from QY were accumulated by NPKM. Similarly, NPKM in contrast to NPK contributed higher Mehlich-3 manganese (M3-Mn) oxide in all aggregate sizes from both sites. Generally, macro-aggregates contributed higher TP, fractions of P, and M3-Mn oxide than micro-aggregates. There was a positive relationship between P pools and M3-Mn oxide at both sites. Additions of animal manure were associated with increased P fractions, and Mn oxides in the paddy soil aggregates, which raises environmental concern.


Assuntos
Agricultura , Solo , Animais , Agricultura/métodos , Fósforo/análise , Fertilizantes/análise , Esterco , Manganês , Hidróxido de Sódio , Óxidos , Nitrogênio/análise , Fertilização , China
2.
PLoS One ; 14(5): e0216881, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31075143

RESUMO

The identification of phosphorus (P) fractions is essential for understanding the transformation and availability of P in paddy soils. To investigate the soil P fractions associated with soil properties under long-term fertilization, we selected three fertilization treatments, including no fertilization (CK), chemical fertilizers (NPK) and chemical fertilizers combined with manure (NPKM), from three long-term experiments located in Nanchang (NC), Jinxian (JX) and Ningxiang (NX). The results showed that chemical fertilizers combined with manure (NPKM) significantly (P ≤ 0.05) increased the soil total phosphorus, Olsen P and soil organic matter (SOM) by 2, 3 and 1 times, respectively, compared with the NPK treatment, and by 4, 17 and 2 times, respectively, compared with the CK treatment. NPKM significantly increased the grain yield compared with CK and NPK at all sites. The apparent P balance with NPK was higher in NC and NX but lower in JX compared with NPKM. Hedley fractionation revealed the predominance of most of the organic and inorganic phosphorus (Po and Pi) fractions with long-term fertilization, especially with the NPKM treatment, at all sites. The nonlabile P pool decreased by 14% and 18% whereas the moderately labile P pool proportions increased by 3 and 6 times with the NPK and NPKM treatments, respectively, compared to the CK treatment. The labile P pool showed a significant positive relationship with the SOM, total P and Olsen P contents. The moderately labile P was positively correlated with the total P and Olsen P. A significant positive correlation was observed between soil pH and the nonlabile P pool. Redundancy analysis revealed that the moderately labile P fraction (HCl dil. Pi fraction) was remarkably increased by the NPKM treatment and significantly correlated with the soil pH and total P concentration. The labile P fraction (NaHCO3-Pi) showed a strong relationship with the Olsen P and total P. However, the residual P fraction was negatively correlated with the HCl. dil. Pi fraction. We concluded that NPKM application improved P availability by many folds compared to NPK, which could lead to environmental pollution; therefore, the rate of combined application of manure and chemical fertilizer should be reduced compared to chemical fertilizer inputs to minimize the wastage of resources and environmental P losses.


Assuntos
Fertilizantes , Esterco , Nitrogênio/análise , Fósforo/análise , Solo/química , Agricultura , China
3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-745311

RESUMO

Objective To compare the effect of different therapeutic methods upon the survival of stage Ⅰ-Ⅱ A cervical cancer patients with intermediate risk factors and explore the optimal treatment for patients with early-stage cervical cancer undergoing radical hysterectomy and pelvic lymphadenectomy.Methods Clinical data of 323 patients with the following intermediate risk factors of lymphovascular space invasion,depth of stromal invasion or tumor size > 4 cm were retrospectively analyzed.The impact of observing (NT),chemotherapy (CT),radiotherapy (RT) and concurrent chemoradiotherapy (CCRT) on survival was statistically compared.The Kaplan-Meier method was used to survival analysis,and log-rank test difference,Cox model was used to prognostic factor analysis.Results The 5-year progression-free survival (PFS) and overall survival (OS) of all patients were 79.0% and 84.8%.Univariate and multivariate analyses demonstrated that TS> 4 cm and therapeutic method were the independent prognostic factors of PFS.The number of risk factors and therapeutic method were the independent prognostic factors of OS.In the whole group,both RT and CCRT could improve the prognosis of patients with no statistical significance (P>0.05).In the subgroup analysis,for patients with a single intermediate risk factor (low risk group),CT could significantly prolong the PFS (P=0.026) rather the 5-year OS (P=0.692).Compared with NT and CT,RT and CCRT could improve the PFS and OS,whereas no statistical significance was noted between the RT and CCRT (both P>0.05).For those with ≥2 risk factors (high risk group),CCRT could significantly prolong the PFS compared with CT (84.9% vs.70%;P=0.006),but did not improve the OS (P=0.107).Compared with RT,CCRT could significantly improve the PFS and OS (both P<0.05).Conclusion For patients with only one risk factor,RT can enhance the clinical prognosis.CCRT can improve the clinical prognosis of stage Ⅰ-Ⅱ A cervical cancer patients with ≥ 2 risk factors.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-745310

RESUMO

Objective To explore the prognostic factors for the recurrence of vaginal stump of earlystage cervical cancer after radical hysterectomy and evaluate the effect on clinical prognosis.Methods Clinical data of stage Ⅰ-ⅡA cervical cancer patients undergoing radical hysterectomy in Guizhou Cancer Hospital from January,2007 to December,2016 were retrospectively analyzed.Results A total of 493 patients were enrolled and followed up until May 30,2018.Among them,96.6%(474/493) completed the follow-up.The median age was 45 years.Patients aged 40-50 years had a high incidence rate.In total,451 cases (91.48%) had no recurrence of vaginal stump.The average time without stump recurrence was 51.2 months and the median time without stump recurrence was 44.8 months.Multivariate Cox regression analysis demonstrated that pelvic external irradiation and brachytherapy were the independent prognostic factors for the recurrence of vaginal stump (P=0.000,0.000).Tumor size,lymph node metastasis and pelvic external irradiation were the independent prognostic factors for overall survival (P=0.045,0.022,0.000).Conclusions Pelvic external irradiation and brachytherapy play an extremely pivotal role in reducing the risk of vaginal stump recurrence after radical hysterectomy for patients with stage Ⅰ-Ⅱ A cervical cancer.Tumor size,lymph node metastasis and pelvic external irradiation are the independent prognostic factors for overall survival of patients with stage Ⅰ-Ⅱ A cervical cancer following radical hysterectomy.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-515214

RESUMO

Objective To investigate the relationship between acute radiation proctitis and radiation dose,volume as well as radiation time,in the process of intensity-modulated radiation therapy (IMRT) for the cervical cancer patients.Methods A total of 51 patients with locally advanced cervical cancer were enrolled from January 2011 to December 2013.Those patients were then classified into grade 1 to 4 groups,according to the RTOG/EORTCtoxicity grading standard.The exposure dose volume and the average dose of rectum under the standard plan were evaluated with dose-volume histogram (DVH).The ANOVA test was used for analyzing Dmax,D mean,D1 cm3,D2cm3,D40 and V40 values of rectum and the average exposure dose of rectum.Results The average time of acute radiation proctitis with clinical symptoms was (23.06 ± 12.01) d after radiotherapy.Dmaxvalues of rectum in grade 2 group was lower than those in grade 3 and 4 groups (F =5.268,P < 0.05).Moreover,D1 cm3 and D2 cm3 values of rectum in grade 1 and 2 groups were also lower than those in grade 3 and 4 groups (F =4.893,4.406,P < 0.05).There was no statistically significant difference between D40 and V40 values.Conclusions The acute radiation proctitis could be frequently found around 20 days during the IMRT for cervical cancer patients.Mild and moderate acute radiation proctitis are more common,while severe acute radiation proctitis is rare.Minimizing Dmax,D1 cm3 and D2 cm3 values of rectum might reduce the incidence of severe acute radiation proctitis in cervical cancer patients receiving IMRT.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-452995

RESUMO

BACKGROUND:Epidermal stem cells as special stem cells of the skin not only plays an important role in maintaining the metabolism of skin, but also is closely related to wound repair, which are the basis for the occurrence and repair of skin and its appendages. Now, epidermal stem cells have been paid great attention on the research of gene therapy and celltherapy with its specific biological advantages. OBJECTIVE:To summarize the research status on features and clinical application of epidermal stem cells. METHODS:A computer-based online retrieval of CNKI, PubMed database and Google scholar was performed for searching papers about clinical application of epidermal stem cells using the keywords of“epidermal stem cells, stem cells division, stem cells culture, clinical application”in Chinese and English. Older theoretical perspectives and repetitive research were excluded. Finally, only 41 articles were included in result analysis. RESULTS AND CONCLUSION:Epidermal stem cells have the great potential of proliferation and multi-directional differentiation, and have important significances for large-area skin defects (burn and trauma), skin tissue engineering, and gene therapy. There are stil many problems that need to be solved, such as how to screen surface markers special for epidermal stem cells and how to induce skin differentiation of epidermal stem cells.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-359196

RESUMO

Singularity is a basic feature of biological signals. Based on the variations of wavelet transform modulus maxima in multi-scales, we studied the basic theorem for analyzing the singularity and proposed an algorithm for calculating lipschitz exponent. Then we applied the algorithm to calculate the singularity of R-wave in ECG. Our study found that the level of singularity of R-waves in ECG between the 10 arrhythm patients randomly chosen and the healthy persons was significantly different, with the level of singularity of R-wave of normal persons remarkably higher than that of arrhythmia patients.


Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Algoritmos , Arritmias Cardíacas , Eletrocardiografia , Métodos , Processamento de Sinais Assistido por Computador , Análise de Ondaletas
8.
Journal of Biomedical Engineering ; (6): 1025-1029, 2010.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-260946

RESUMO

Filter pass-band settings have impact not only on ECG output amplitude, but also on output signal wave-form of some types of digital electrocardiograph. Lower cut-off frequency is decided by Wander filter setting for some types of digital electrocardiograph, and higher cut-off frequency is decided by muscle filter when muscle filter functionality is "on". We research into various filter settings' impact on the output of digital electrocardiograph and have discussions on the malfunctions found in digital electrocardiograph measurement.


Assuntos
Humanos , Algoritmos , Artefatos , Eletrocardiografia , Métodos , Desenho de Equipamento , Processamento de Sinais Assistido por Computador
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