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1.
Sci Total Environ ; 926: 172016, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38547999

RESUMEN

Vegetables are the most consumed non-staple food globally, and their production is crucial for dietary diversity and public health. Use of enhanced-efficiency fertilizers (EEFs) in vegetable production could improve vegetable yield and quality while reducing reactive nitrogen (Nr) losses. However, different management and environmental factors has significantly distinctive impacts on the effectiveness of EEFs. In this study, a worldwide meta-analysis based on the data collected from 144 studies was performed to assess the impacts of EEF (nitrification inhibitor [NI] and polymer-coated urea [PCU]) application on vegetable yield, nitrogen (N) uptake, nitrogen use efficiency (NUE), vegetable quality and Nr losses (nitrous oxide [N2O] emissions, ammonia [NH3] volatilization, and nitrate [NO3-] leaching). The effects of the applied EEFs on vegetable yields and N2O emissions were assessed with different management practices (cultivation system, vegetable type and N application rate) and environmental conditions (climatic conditions and soil properties). Compared to conventional fertilizers, EEFs significantly improved vegetable yield (7.5-8.1 %) and quality (vitamin C increased by 10.7-13.6 %, soluble sugar increased by 9.3-10.9 %, and nitrate content reduced by 17.2-25.1 %). Meanwhile, the application of EEFs demonstrated a great potential for Nr loss reduction (N2O emissions reduced by 40.5 %, NO3- leaching reduced by 45.8 %) without compromising vegetable yield. The NI was most effective in reducing N2O emissions (40.5 %), but it significantly increased NH3 volatilization (32.4 %). While PCU not only significantly reduced N2O emissions (24.4 %) and NO3- leaching (28.7 %), but also significantly reduced NH3 volatilization (74.5 %). And N application rate, soil pH, and soil organic carbon (SOC) were the main factors affecting the yield and environmental effects of EEFs. Moreover, the yield-enhancing effect of NI and PCU were better at low soil N availability and SOC, respectively. Thus, it is important to adopt the appropriate EEF application strategy targeting specific environmental conditions and implement it at the optimal N application rate.


Asunto(s)
Suelo , Verduras , Suelo/química , Agricultura , Nitrógeno/análisis , Fertilizantes/análisis , Carbono , Nitratos , Óxido Nitroso/análisis , Amoníaco/análisis , Urea
2.
Glob Health Res Policy ; 8(1): 53, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38105284

RESUMEN

Primary health care (PHC) is the most effective way to improve people's health and well-being, and primary care services should act as the cornerstone of a resilient health system and the foundation of universal health coverage. To promote high quality development of PHC, an International Symposium on Quality Primary Health Care Development was held on December 4-5, 2023 in Beijing, China, and the participants have proposed and advocated the Beijing Initiative on Quality Primary Health Care Development. The Beijing Initiative calls on all countries to carry out and strengthen 11 actions: fulfill political commitment and accountability; achieve "health in all policies" through multisectoral coordination; establish sustainable financing; empower communities and individuals; provide community-based integrated care; promote the connection and integration of health services and social services through good governance; enhance training, allocation and motivation of health workforce, and medical education; expand application of traditional and alternative medicine for disease prevention and illness healing; empower PHC with digital technology; ensure access to medicinal products and appropriate technologies; and last, strengthen global partnership and international health cooperation. The Initiative will enrich the content of quality development of PHC, build consensus, and put forward policies for quality development of PHC in China in the new era, which are expected to make contributions in accelerating global actions.


Asunto(s)
Atención Primaria de Salud , Cobertura Universal del Seguro de Salud , Humanos , Beijing , Atención a la Salud , Calidad de la Atención de Salud
3.
Curr Med Imaging ; 19(6): 654-657, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36263473

RESUMEN

INTRODUCTION: Hemangioblastomas are highly vascular benign tumors that may increase in size during pregnancy. The concurrence of cerebellar hemangioblastoma in high-risk pregnancy is extremely rare and the treatment in this situation can be challenged. CASE: Here, we report a case of a 30-year-old woman in the 33rd PW who had experienced a severe headache, dizziness, vomiting, and limb weakness. Cesarean section was performed in the 34th PW, followed by neurosurgery under multidisciplinary discussion. DISCUSSION: The pathological exam suggested hemangioblastomas. Finally, both the pregnancy and the fetus had a good outcome. CONCLUSION: This case emphasizes that the timing of surgery should be determined according to the neurological symptoms of the pregnancy and the gestational age (GA) and condition of the fetus.


Asunto(s)
Neoplasias Cerebelosas , Hemangioblastoma , Humanos , Embarazo , Femenino , Adulto , Hemangioblastoma/diagnóstico por imagen , Hemangioblastoma/cirugía , Embarazo de Alto Riesgo , Cesárea , Neoplasias Cerebelosas/diagnóstico por imagen , Neoplasias Cerebelosas/cirugía
4.
Plants (Basel) ; 11(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36235377

RESUMEN

Assessment of the nitrogen (N) inputs and outputs in croplands would help effectively manage the distribution of N to improve crop growth and environmental sustainability. To better understand the N flow of the main cereal systems in China, soil N balance, N use efficiency (NUE), N losses and the potential environmental impacts of maize, wheat and rice cropping systems were estimated at the regional and national scales from 2004 to 2018. Nationally, the soil N balance (N inputs-N outputs) of maize, wheat, single rice and double rice decreased by 28.8%,13.3%, 30.8% and 34.1% from 2004-2008 to 2014-2018, equivalent to an average of 33.3 to 23.7 kg N ha-1, 82.4 to 71.4 kg N ha-1, 93.6 to 64.8 kg N ha-1 and 51.8 to 34.1 kg N ha-1, respectively. The highest soil N balance were observed in Southeast (SE) region for maize and double rice, North central (NC) region for wheat single rice and Northwest region for wheat, whereas Northeast (NE) region had the lowest N balance for all crops. The NUE increased from 49.8%, 41.2%, 49.7% and 53.7% in 2004-2008 to 54.8%, 45.9%, 55.5% and 56.5% in 2014-2018 for maize, wheat, single rice and double rice, respectively. The fertilizer N losses (i.e., N2O emission, NO emission, N2 emission, NH3 volatilization, N leaching and N runoff) were estimated as 43.7%, 38.3%, 40.2% and 36.6% of the total N inputs for maize, wheat, single rice and double rice, respectively in 2014-2018. Additionally, the highest global warming potential and acidification effects were found in NE and NC regions for maize, NC region for wheat, the middle and lower reaches of Yangtze River for single rice and SE region for double rice, respectively. The highest risk of water contamination by N leaching and surface runoff was observed in NC region for all crops mainly due to high N fertilizer input. Furthermore, the dynamics of N balance for all crops were closely tied with grain yields, except for single rice, the N balance of which was mainly correlated with N fertilizer input. Our results could help researchers and policy makers effectively establish optimized fertilization strategies and adjust the regional allocation of grain cropping areas in response to environmental risks and climate change caused by food crop cultivation in China.

5.
Glob Chang Biol ; 28(17): 5121-5141, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35678108

RESUMEN

Inhibitors are widely considered an efficient tool for reducing nitrogen (N) loss and improving N use efficiency, but their effectiveness is highly variable across agroecosystems. In this study, we synthesized 182 studies (222 sites) worldwide to evaluate the impacts of inhibitors (urease inhibitors [UI], nitrification inhibitors [NI] and combined inhibitors) on crop yields and gaseous N loss (ammonia [NH3 ] and nitrous oxide [N2 O] emissions) and explored their responses to different management and environmental factors including inhibitor application timing, fertilization regime, cropping system, water management, soil properties and climatic conditions using subgroup meta-analysis, meta-regression and multivariate analyses. The UI were most effective in enhancing crop yields (by 5%) and reducing NH3 volatilization (by 51%), whereas NI were most effective at reducing N2 O emissions (by 49%). The application of UI mitigates NH3 loss and increases crop yields especially in high NH3 -N loss scenarios, whereas NI application would minimize the net N2 O emissions and the resultant environmental impacts especially in low NH3 -N loss scenarios. Alternatively, the combined application of UI and NI enables producers to balance crop production and environmental conservation goals without pollution tradeoffs. The inhibitor efficacy for decreasing gaseous N loss was dependent upon soil and climatic conditions and management practices. Notably, both meta-regression and multivariate analyses suggest that inhibitors provide a greater opportunity for reducing fertilizer N inputs in high-N-surplus systems and presumably favor crop yield enhancement under soil N deficiency situations. The pursuit of an improved understanding of the interactions between plant-soil-climate-management systems and different types of inhibitors should continue to optimize the effectiveness of inhibitors for reducing environmental losses while increasing productivity.


Asunto(s)
Óxido Nitroso , Suelo , Agricultura , Amoníaco/análisis , Fertilizantes/análisis , Nitrógeno/análisis , Óxido Nitroso/análisis
6.
J Environ Manage ; 318: 115583, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35753128

RESUMEN

The excessive and inappropriate application of nitrogen (N) fertilizer in open vegetable fields is a major anthropogenic source of gaseous N losses including nitrous oxide (N2O) and ammonia (NH3) emissions in China. A 2-yr Chinese cabbage (Brassica pekinensis L.) experiment was carried out to explore the impacts of optimized N management (reduced N application rate, controlled-release urea [CRF] and nitrification inhibitor [NI]) on cabbage yield, soil inorganic N, and N2O and NH3 emissions, and to assess their economic benefits by a cost-benefit analysis. Six treatments including i) no N fertilizer (CK), ii) conventional urea fertilizer at 400 kg N ha-1 based on farmers' practices (CN), iii) conventional urea at 320 kg N ha-1 (RN), iv) conventional urea (320 kg N ha-1) with the addition of NI (RN + NI), v) CRF at 320 kg N ha-1 (CR) and vi) CRF (320 kg N ha-1) with the addition of NI (CR + NI) were implemented in an open Chinese cabbage field. No significant differences were found in the cabbage yields and soil NH4+-N contents under different N fertilization treatments. Only CR + NI treatment had significantly lower soil NO3--N contents than CN by 17.6%-34.6% at the early growing stages of cabbage in both years. Compared with CN, the N2O emissions were significantly decreased by 8.61%, 34.4%, 37.8% and 46.6% under RN, RN + NI, CR and CR + NI, respectively, indicating that CR + NI favors N2O abatement especially when NH3 has been suppressed by other 4 R practices. Meanwhile, the NH3 volatilization was 20.6% higher under RN + NI and 30.8% and 17.3% lower under CR and CR + NI compared to CN, respectively, which implied that CR was the most effective treatment in reducing the NH3 volatilization and total gaseous N loss in high NH3-N loss scenarios. Moreover, the net benefit of RN decreased by $945 USD ha-1 and those of RN + NI, CR and CR + NI treatments increased by $855, $930 and $1004 USD ha-1 compared to CN, respectively. This study recommends CR + NI as the optimal N fertilizer management for the sustainable production of vegetables with the lowest environmental risks and the greatest economic benefits.


Asunto(s)
Brassica , Nitrógeno , Agricultura , Amoníaco/análisis , Fertilizantes/análisis , Gases , Nitrógeno/análisis , Óxido Nitroso/análisis , Suelo , Urea , Verduras
7.
Plants (Basel) ; 12(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36616210

RESUMEN

Open vegetable fields in China are a major anthropogenic source of nitrous oxide (N2O) emissions due to excessive nitrogen (N) fertilization. A 4 yr lettuce experiment was conducted to determine the impacts of controlled-release fertilizers (CRFs) and nitrification inhibitors (NIs) on lettuce yield, N2O emissions and net economic benefits. Five treatments included (i) no N fertilizer (CK), (ii) conventional urea at 255 kg N ha-1 based on farmers' practice (FP), (iii) conventional urea at 204 kg N ha-1 (OPT), (iv) CRF at 204 kg N ha-1 (CU) and (v) CRF (204 kg N ha-1) added with NI (CUNI). No significant differences were found in the lettuce yields among different N fertilization treatments. Compared with FP, the cumulative N2O emissions were significantly decreased by 8.1%, 38.0% and 42.6% under OPT, CU and CUNI, respectively. Meanwhile, the net benefits of OPT, CU and CUNI were improved by USD 281, USD 871 and USD 1024 ha-1 compared to CN, respectively. This study recommends the combined application of CRF and NI at a reduced N rate as the optimal N fertilizer management for the sustainable production of vegetables in China with the lowest environmental risks and the greatest economic benefits.

8.
Case Rep Neurol ; 13(1): 259-266, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34054465

RESUMEN

Solitary fibrous tumor is a very rare mesenchymal tumor that occurs mostly in the pleura, and there are few reported cases of a presence in the central nervous system, particularly in the cerebellum. In 2016, the WHO classified solitary fibrous tumors into grade I. In this article, we present a case of malignant solitary fibrous tumor recurring 8 years after surgery in a 63-year-old male. Magnetic resonance imaging showed low to intermediate mixed signal intensity on T1W1. Immunohistochemical staining positivity for Vimentin, CD99, CD34 and Bcl-2, it is consistent with the immunohistochemical characteristics of solitary fibrous tumor. We resected the patient's tumor, and the patient was followed up for 3 months with no signs of recurrence. Solitary fibrous tumors are very rare in the central nervous system. Immunohistochemical staining positivity for CD34 and Bcl-2 is strongly expressed in most solitary fibrous tumor. Surgical resection is the preferred treatment. Due to the small number of cases, the biological behavior and prognosis of this tumor need to be further explored.

9.
Medicine (Baltimore) ; 96(50): e9086, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29390304

RESUMEN

RATIONALE: Meningiomas are mostly regarded as benign tumors histologically,accounting for 13% to 26% of all primary intracranial tumors.It is testified that multiple meningiomas occur in <10% of cases.A case of concurrent grades I and II in the same patient in our hospital was described. PATIENT CONCERN: A 66-year-old man who was experiencing headache and weakening in the left limbs, which gradually improved.Then, the myodynamia of left limb was weakening to level 3 and the muscular tension of left limbwas too strong for 1 year. Finally the man was admitted to our department of neurosurgery. DIAGNOSES: According the symptoms, signs and imaging data the patient. The 2 masses was diagnosed as the meningioma.Finally the histological examination showed the meningioma located in the right parietal lobe was diagnosed as fibrous meningioma,WHOgrade I, whereas meningioma reaching to the skull as atypical meningioma, WHO grade II. INTERVENTIONS: The 2 masses including the invaded dura mater,parietal skull, and adjacent subcutaneous tissue were excised wholly In the process of surgery. OUTCOMES: There is no sign caused by recurrent tumor. within the half year.The physical of the patient is good LESSONS:: The patient with multicentric meningiomas should keep follow-up closely in case the meningiomas show the malignant characteristics.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias Meníngeas/patología , Meningioma/patología , Anciano , Neoplasias Encefálicas/cirugía , Humanos , Masculino , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Clasificación del Tumor , Lóbulo Parietal/patología
10.
Int J Environ Res Public Health ; 12(7): 7100-17, 2015 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-26114243

RESUMEN

The purpose of this study was to assess soil heavy metal contamination and the potential risk for local residents in Suxian county of Hunan Province, southern China. Soil, rice and vegetable samples from the areas near the mining industrial districts were sampled and analyzed. The results indicate that the anthropogenic mining activities have caused local agricultural soil contamination with As, Pb, Cu and Cd in the ranges of 8.47-341.33 mg/kg, 19.91-837.52 mg/kg, 8.41-148.73 mg/kg and 0.35-6.47 mg/kg, respectively. GIS-based mapping shows that soil heavy metal concentrations abruptly diminish with increasing distance from the polluting source. The concentrations of As, Pb, Cu and Cd found in rice were in the ranges of 0.02-1.48 mg/kg, 0.66-5.78 mg/kg, 0.09-6.75 mg/kg, and up to 1.39 mg/kg, respectively. Most of these concentrations exceed their maximum permissible levels for contaminants in foods in China. Heavy metals accumulate to significantly different levels between leafy vegetables and non-leafy vegetables. Food consumption and soil ingestion exposure are the two routes that contribute to the average daily intake dose of heavy metals for local adults. Moreover, the total hazard indices of As, Pb and Cd are greater than or close to the safety threshold of 1. Long-term As, Pb and Cd exposure through the regular consumption of the soil, rice and vegetables in the investigated area poses potential health problems to residents in the vicinity of the mining industry.


Asunto(s)
Monitoreo del Ambiente , Contaminación de Alimentos/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Suelo/química , Adulto , Niño , China , Humanos , Minería , Oryza/química , Medición de Riesgo , Verduras/química
11.
Int J Environ Res Public Health ; 10(10): 5163-77, 2013 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-24135822

RESUMEN

Metal mines release toxic substances into the environment and can therefore negatively impact the health of residents in nearby regions. This paper sought to investigate whether there was excess disease mortality in populations in the vicinity of the mining area in Suxian District, South China. The spatial distribution of metal mining and related activities from 1985 to 2012, which was derived from remote sensing imagery, was overlapped with disease mortality data. Three hotspot areas with high disease mortality were identified around the Shizhuyuan mine sites, i.e., the Dengjiatang metal smelting sites, and the Xianxichong mine sites. Disease mortality decreased with the distance to the mining and smelting areas. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. The risk of dying according to disease mortality rates was analyzed within 7-25 km buffers. The results suggested that there was a close relationship between the risk of disease mortality and proximity to the Suxian District mining industries. These associations were dependent on the type and scale of mining activities, the area influenced by mining and so on.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Ambientales/efectos adversos , Contaminación Ambiental/efectos adversos , Metales , Minería , China , Demografía , Ecosistema , Exposición a Riesgos Ambientales , Sistemas de Información Geográfica , Humanos , Mortalidad , Tecnología de Sensores Remotos , Factores de Tiempo
12.
Huan Jing Ke Xue ; 33(1): 110-6, 2012 Jan.
Artículo en Chino | MEDLINE | ID: mdl-22452197

RESUMEN

Basing on the data of livestock in 2001-2009 in Anhui province, the farmland pollution loading and water equal standard pollution loading of livestock manure were calculated utilizing the discharge rate of livestock manure. In addition, the risk assessment was evaluated on the livestock pollution in farmland and water bodies in this province. The industrial production of animal manure of this industry in 2008-2009 in Anhui amounted to 0.67 billion tons, and the averaged farmland loading of livestock manure, N, and P were 16.2 t x hm(-2), 83.8 kg x hm(-2), and 34.5 kg x hm(-2), respectively. The overall averaged risk constant of livestock manure loading in farmland was 0.36 (approximately risk level I). As to the water bodies, the averaged equal standard pollution loading was 7.03. However, significant differences were observed for the farmland and water contamination with livestock manure in different areas of Anhui, suggesting that some areas might receive much higher doses than the averaged amounts. The contamination weakened comparing with that in 2001-2002. But there was a trend of increase for P pollution. According to the information in 2008-2009, the farmland and water bodies in the areas of Hefei, Suzhou, and Bengbu still borne the livestock manure contamination. Results of this work provide some useful information for the water and farmland environmental protection in Huaihe river basin in Anhui province.


Asunto(s)
Ganado , Estiércol , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis , Animales , China , Productos Agrícolas/crecimiento & desarrollo , Monitoreo del Ambiente , Nitrógeno/análisis , Fósforo/análisis , Aves de Corral , Medición de Riesgo
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