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1.
Ecol Appl ; 33(2): e2757, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36193869

RESUMO

The desertification reversal is a process of revegetation and natural restoration in fragile dryland areas due to human activities and climate change mediation. Understanding the impact of desertification reversion on terrestrial ecosystems, including vegetation greenness and photosynthetic capacity, is crucial for land policy-making and carbon-cycle model improvement. However, the phenomenon of desertification reversal is rarely mentioned in previous studies, which dramatically limits the understanding of vegetation dynamics in the arid area. Therefore, it is of great necessity to investigate the status of desertification reversal on the ecosystem in arid areas. In this study, we first reported the phenomenon of desertification reversion over the southern edge of the Gurbantunggut Desert through the Moderate-resolution Imaging Spectroradiometer classification map year by year. We discussed the consequences, ways, and causes of desertification reversion. Our results showed that the desertification reversal significantly increased vegetation greenness and photosynthetic capacity, which largely offset the negative impact of desertification on the ecosystem productivity; cropland expansion and grassland's natural restoration were the two main ways of desertification reversal; the improvement of soil-water condition was an essential environmental factor leading to the phenomenon of reverse desertification. This finding highlights the importance of desertification reversal in the carbon cycle of dryland ecosystems and prove that desertification reversal is an integral part of global and dryland vegetation greening.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Fluorescência , Clima Desértico , Clorofila , China
2.
N Engl J Med ; 387(15): 1373-1384, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36239645

RESUMO

BACKGROUND: The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied. METHODS: In a trial conducted over a 5-year period in China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality. RESULTS: A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval [CI], 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy. CONCLUSIONS: Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).


Assuntos
Arteriopatias Oclusivas , Artéria Basilar , Procedimentos Endovasculares , Acidente Vascular Cerebral , Trombectomia , Humanos , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/mortalidade , Arteriopatias Oclusivas/cirurgia , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/cirurgia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Isquemia Encefálica/cirurgia , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etiologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Fatores de Tempo , Resultado do Tratamento
3.
Exp Ther Med ; 10(1): 145-153, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26170926

RESUMO

The aim of the present study was to analyze the feasibility, rate of procedure-related complications and midterm angiographic follow-up outcomes using the Enterprise (EP) and Solitaire™ AB (ST) stents in the stent-assisted coiling of intracranial aneurysms. In total, 81 patients with 90 aneurysms were included in the study, with the aim to treat 43 aneurysms with the EP stent (47.8%) and 47 aneurysms with the ST stent (52.2%). The 90 aneurysms were successfully stented and subsequently coiled; however, in four patients undergoing treatment with the EP stent, the stent was not navigable; thus, treatment with the ST stent was employed (EP, n=39, 43.3%; ST, n=51, 56.7%). Of the 90 aneurysms, 44 cases were ruptured aneurysms, with 74 located in the anterior circulation and 16 located in the posterior circulation. The stenting success rate of the ST stent was significantly higher compared with the EP stent. However, no statistically significant differences were observed with regard to the packing density, complete occlusion, progressive occlusion, recurrence rate, procedure-related complications, in-stent stenosis and stent migration rates between the two groups. In conclusion, the two common medical devices used for intracranial aneurysms are relatively safe and effective for the treatment of intracranial aneurysms. However, due to the higher stenting success rate of the ST stent, this medical devise was demonstrated to be more flexible and feasible compared with the EP stent.

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