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1.
Environ Res ; 257: 119251, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38815714

RESUMEN

The bioavailable diverse dissolved organic matter (DOM) present in glacial meltwater significantly contributes to downstream carbon cycling in mountainous regions. However, the comprehension of molecular-level characteristics of riverine DOM, from tributary to downstream and their fate in glacier-fed desert rivers remains limited. Herein, we employed spectroscopic and high-resolution mass spectrometry techniques to study both optical and molecular-level characteristics of DOM in the Tarim River catchment, northwest China. The results revealed that the DOC values in the downstream were higher than those in the tributaries, yet they remained comparable to those found in other glacier-fed streams worldwide. Five distinct components were identified using EEM-PARAFAC analysis in both tributary and downstream samples. The dominance of three protein-like components in tributary samples, contrasting with a higher presence of humic-like components in downstream samples, which implied that the dilution and alterations of the glacier DOM signature and overprinting with terrestrial-derived DOM. Molecular composition revealed that thousands of compounds with higher molecular weight and increased aromaticity were transformed, generated and introduced from terrestrial inputs during downstream transportation. The twofold rise in polycyclic aromatic and polyphenolic compounds observed downstream compared to tributaries indicated a greater influx of terrestrial organic matter introduced into the downstream during water transportation. The study suggests that the glacier-sourced DOM experienced minimal photodegradations, with limited influence from human activities, while also being shaped by terrestrial inputs during its transit in the alpine-arid region. This unique scenario offers valuable insights into comprehending the fate of DOM originating from glacial meltwater in arid mountainous regions.


Asunto(s)
Cubierta de Hielo , Ríos , China , Ríos/química , Cubierta de Hielo/química , Monitoreo del Ambiente/métodos , Compuestos Orgánicos/análisis , Contaminantes Químicos del Agua/análisis , Sustancias Húmicas/análisis , Espectrometría de Masas , Clima Desértico
2.
Water Res ; 249: 120881, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38016225

RESUMEN

Pharmaceuticals and personal care products (PPCPs) are emerging contaminants that have raised urgent environmental issues. The dissolved organic matter (DOM) plays a pivotal role on PPCPs' migration and transformation. To obtain a comprehensive understanding of the occurrence and distribution of PPCPs, a seasonal sampling focused on the riverine system in coastal zone, Tianjin, Bohai Rim was conducted. The distribution and transformation of thirty-three PPCPs and their interaction with DOM were investigated, and their sources and ecological risks were further evaluated. The total concentration of PPCPs ranges from 0.01 to 197.20 µg/L, and such value is affected by regional temperature, DOM and land use types. PPCPs migration at soil-water interface is controlled by temperature, sunlight, water flow and DOM. PPCPs have a high affinity to the protein-like DOM, while the humus-like DOM plays a negative influence and facilitates PPCPs' degradation. It is also found that protein-like DOM can represent point source pollution, while humus-like substances indicate non-point source (NPS) emission. Specific PPCPs can be used as markers to trace the source of domestic discharge. Additionally, daily use PPCPs such as ketoprofen, caffeine and iopromide are estimated to be the main risk substances, and their ecological risk varies on space, season and river hydraulic condition.


Asunto(s)
Cosméticos , Contaminantes Químicos del Agua , Estaciones del Año , Materia Orgánica Disuelta , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Cosméticos/análisis , China , Agua , Suelo , Ríos , Preparaciones Farmacéuticas
3.
World J Clin Cases ; 9(33): 10279-10285, 2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34904100

RESUMEN

BACKGROUND: Cerebral hemorrhage secondary to cerebral embolism after mechanical thrombectomy is characterized by high morbidity, disability and mortality. If the patient also has severe pulmonary embolism (PE) at the same time, the treatment becomes more complex. This report describes the treatment strategy for a patient with PE and cerebral hemorrhage secondary to cerebral embolism after mechanical thrombectomy. CASE SUMMARY: A 70-year-old woman presented to our emergency department with right-sided hemiplegia and mixed aphasia of 2.5 h duration. She was diagnosed with left cerebral embolism, left internal carotid artery occlusion, PE and left calf intramuscular vein thrombosis. Following mechanical thrombectomy, brain magnetic resonance imaging showed cerebral infarction with basal ganglia hemorrhage. We observed changes in cerebral hemorrhage on serial monitoring of brain computed tomography and adjusted the dose of anticoagulant drugs. After 3 wk of treatment, the patient's neurological and respiratory symptoms significantly improved, and a favorable prognosis was obtained. CONCLUSION: Anticoagulation could be a potential option for PE accompanied by hemorrhagic transformation of an ischemic infarct.

4.
J Clin Neurosci ; 63: 17-21, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30850180

RESUMEN

This retrospective study is to investigate the safety and efficacy of the stent implanting for treating severe symptomatic atherosclerotic stenosis of the intracranial vertebrobasilar artery (ICVBA). 213 patients who had undergone intervention for severe symptomatic ICVBA stenosis between September 2012 to May 2018 were enrolled into this study. Among the 213 enrolled patients, 210 patients (98.6%) obtained successfully revascularization and 206 patients (96.7%) had good revascularization after stenting. The extent of stenosis before and after intervention was 86.3 ±â€¯6.8% and 9.1 ±â€¯3.7%, respectively. Within 90 days after stenting, 10 patients (4.7%) experienced primary endpoint events, including 4 cases (4.2%) in the intracranial vertebral artery (V4) group and 6 (5.1%) in basilar artery (BA) group. Among them, 2 (2.1%) and 3 cases (2.5%) of ischemic stroke in V4 and BA group, respectively; and 2 (2.1%) and 2 (1.7%) cases of TIA in V4 and BA group, respectively. One (0.8%) case in the BA group dead because of the acute stent occlusion resulted in the top of the basilar syndrome. Six patients (2.8%) experienced adverse events, including 2 (2.1%) and 4 (3.4%) cases of groin hematoma in the V4 and BA group, respectively. No cases of hemorrhagic stroke, stent dislocation and vessel dissection in both groups. Our study showed that a low complication rate and a high and good revascularization rate would be achieved by the treatment of severe symptomatic atherosclerotic stenosis of the ICVBA using the stents.


Asunto(s)
Angioplastia/efectos adversos , Hemorragias Intracraneales/epidemiología , Complicaciones Posoperatorias/epidemiología , Stents/efectos adversos , Accidente Cerebrovascular/epidemiología , Insuficiencia Vertebrobasilar/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aterosclerosis/complicaciones , Aterosclerosis/cirugía , Femenino , Humanos , Hemorragias Intracraneales/etiología , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/etiología , Insuficiencia Vertebrobasilar/etiología
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