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1.
Sci Data ; 10(1): 765, 2023 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-37925513

RESUMEN

China contributed nearly one-fifth of the world maize production over the past few years. Mapping the distributions of maize cropland in China is crucial to ensure global food security. Nonetheless, 10 m maize cropland maps in China are still unavailable, restricting the promotion of sustainable agriculture. In this paper, we collect numerous samples to produce annual 10-m maize cropland maps in China from 2017 to 2021 with a machine learning based classification framework. To overcome the temporal variations of plants, the proposed framework takes Sentinel-2 sequence images as input and utilizes deep neural networks and random forest as classifiers to map maize in a zone-specific way. The generated maps have an overall accuracy (OA) spanning from 0.87 to 0.95 and the maize-cultivated areas estimated by the maps are highly consistent with the records in statistical yearbooks (R2 varying from 0.83 to 0.95). To the best of our knowledge, this is the first annual 10-m maize maps across China, which largely facilitates the sustainable agriculture development in China dominated by smallholder farmlands.


Asunto(s)
Agricultura , Zea mays , Agricultura/métodos , China , Productos Agrícolas
2.
Sci Data ; 10(1): 437, 2023 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-37419886

RESUMEN

As the major maize-cultivated areas, the one-season cropland of China is increasingly threatened by rapid urbanization and soybean rejuvenation. Quantifying the area changes of maize cropland is crucial for both food and energy security. Nonetheless, due to the lack of survey data related to planting types, long-term and fine-grained maize cropland maps in China dominated by small-scale farmlands are still unavailable. In this paper, we collect 75,657 samples based on field surveys and propose a deep learning-based method according to the phenology information of maize. With the generalization capability, the proposed method produces maize cropland maps with a resolution of 30 m from 2013 to 2021 in the one-season planting areas of China. The maize-cultivated areas derived from the maps are highly consistent with the data recorded by statistical yearbooks (R2 = 0.85 on average), which indicates that the produced maps are reliable to facilitate the research on food and energy security.


Asunto(s)
Productos Agrícolas , Zea mays , China , Estaciones del Año
3.
RSC Adv ; 8(11): 6013-6026, 2018 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35539596

RESUMEN

Active targeting of tumor receptors is a significant approach for cancer diagnosis. Additionally, development of photothermal agents for photothermal therapy (PTT) has attracted great interest in the field of nanomedicine. In the present study, copper sulfide (CuS) nanoparticles capped with bovine serum albumin (BSA), named CuS@BSA, was synthesized by a convenient method. Then, the near-infrared (NIR) fluorescence probe MBA and the tumor-targeting ligand cyclic RGD were further conjugated on the surface of CuS@BSA, and the obtained nanocomposite was named CuS@BSA-MBA-cRGD. The morphology, optical properties, biotoxicity, tumor-targeting capability and in vitro and in vivo tumor inhibition effect were all characterized comprehensively. This nanocomplex demonstrated enhanced photothermal effects and positive tumor targeting. Thus, the nanocomposite CuS@BSA-MBA-cRGD can used as a promising tumor-targeting PTT agent for simultaneous cancer imaging and photothermal treatment.

4.
Biomater Sci ; 5(3): 475-484, 2017 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-28078340

RESUMEN

Near-infrared (NIR) photothermal therapy (PTT) is a new approach to ablate cancer without affecting normal tissues. A pivotal concern of PPT is to develop photo-responsive agents with high biocompatibility as well as effective photothermal conversion efficiency. Copper sulfide (CuS) nanoparticles prepared are characterized by their low synthesis cost, wide NIR absorption range, good biocompatibility and favorable NIR photothermal conversion efficiency. CuS nanoparticles were then coated with mesoporous silicon dioxide (SiO2) by the Stober method, and further loaded with anticancer drug doxorubicin (DOX). The nanocomposites obtained were named CuS@MSN-DOX. The infrared thermal imaging of CuS@MSN-DOX demonstrated its favorable photothermal efficacy. The potential of CuS@MSN-DOX utilized as a multifunctional platform for combined PPT and chemotherapy was exploited both at the cell level and in a mice model. The result demonstrated that CuS@MSN-DOX was endowed with the synergistic effect of chemo-photothermal therapy, which confirmed that it is a promising candidate for combined therapy of cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Cobre/uso terapéutico , Doxorrubicina/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias/terapia , Animales , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Liberación de Fármacos , Humanos , Hipertermia Inducida/métodos , Ratones , Fototerapia/métodos , Dióxido de Silicio/uso terapéutico
5.
Biomaterials ; 100: 1-16, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27236844

RESUMEN

Dual targeting towards both extracellular and intracellular receptors specific to tumor is a significant approach for cancer diagnosis and therapy. In the present study, a novel nano-platform (AuNC-cRGD-Apt) with dual targeting function was initially established by conjugating gold nanocluster (AuNC) with cyclic RGD (cRGD) that is specific to αvß3integrins over-expressed on the surface of tumor tissues and aptamer AS1411 (Apt) that is of high affinity to nucleolin over-expressed in the cytoplasm and nucleus of tumor cells. Then, AuNC-cRGD-Apt was further functionalized with near infrared (NIR) fluorescence dye (MPA), giving a NIR fluorescent dual-targeting probe AuNC-MPA-cRGD-Apt. AuNC-MPA-cRGD-Apt displays low cytotoxicity and favorable tumor-targeting capability at both in vitro and in vivo level, suggesting its clinical potential for tumor imaging. Additionally, Doxorubicin (DOX), a widely used clinical chemotherapeutic drug that kill cancer cells by intercalating DNA in cellular nucleus, was immobilized onto AuNC-cRGD-Apt forming a pro-drug, AuNC-DOX-cRGD-Apt. The enhanced tumor affinity, deep tumor penetration and improved anti-tumor activity of this pro-drug were demonstrated in different tumor cell lines, tumor spheroid and tumor-bearing mouse models. Results in this study suggest not only the prospect of non-toxic AuNC modified with two targeting ligands for tumor targeted imaging, but also confirm the promising future of dual targeting AuNC as a core for the design of prodrug in the field of cancer therapy.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Oro/química , Sustancias Luminiscentes/química , Nanoconjugados/química , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Animales , Antibióticos Antineoplásicos/uso terapéutico , Aptámeros de Nucleótidos , Línea Celular Tumoral , Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Nanopartículas del Metal/química , Ratones Desnudos , Microscopía Confocal , Oligodesoxirribonucleótidos/química , Péptidos Cíclicos/química
6.
Mol Pharm ; 12(7): 2505-16, 2015 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-26030231

RESUMEN

Chloramphenicol (CAP) is one of the most effective antimicrobial agents, but its therapeutic efficacy is greatly limited by its nonspecific distribution and consequent side effects in neutrophils. Targeting to the infection sites, and thus restricting CAP nonselective delivery, provides an alternative way to overcome this limitation. The antibacterial peptide fragment UBI29-41 was identified to have a high bacterial affinity. However, no research so far has been carried out to utilize UBI29-41 as a ligand for bacteria-targeting therapies. In this Article, we first labeled a near-infrared fluorescent dye (ICG02) with UBI29-41 to investigate its targeting capability in different bacteria (S. aureus, E. coli, and P. auruginosa) and bacteria-infected mouse models. Subsequently, UBI29-41 was conjugated with the typical antibiotic (CAP) through the linker glutaric anhydride to form the conjugate CAP-UBI29-41 for the bacteria-targeting therapy. In vitro studies demonstrated the enhanced antibacterial effects of CAP-UBI29-41 on S. aureus and E.coil. Meanwhile, the toxicity of CAP-UBI29-41 on normal cells decreased distinctly in comparison with CAP. Most importantly, CAP-UBI29-41 exhibited more favorable antibacterial efficacy than CAP in bacteria-bearing mouse models. All these results demonstrated that UBI29-41 is an ideal targeting ligand to construct antibacterial agents for bacteria-targeting therapy.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Fragmentos de Péptidos/farmacología , Animales , Línea Celular , Cloranfenicol/farmacología , Humanos , Ratones , Ratones Endogámicos ICR , Espectroscopía Infrarroja Corta/métodos
7.
Lin Chuang Er Bi Yan Hou Ke Za Zhi ; 18(3): 152-4, 2004 Mar.
Artículo en Chino | MEDLINE | ID: mdl-15222266

RESUMEN

OBJECTIVE: To study the value of laryngeal endoscopic system in the treatment of laryngeal diseases with minimally invasive surgery. METHOD: This paper was to summarized retrospectively the clinical experience of 34 cases suffered from laryngeal diseases treated by minimally invasive surgery with laryngeal endoscopic system. The remain tumor and hemorrhage were treated by microwave machine. The malignant tumors were treated by radiotherapy with 60Co in 40 Gy, postoperatively. RESULT: The tumors were totally resected and no serious complications were revealed. Followed-up these 34 cases, 26 cases with benign pathological changes who had hoarseness preoperatively recovered to normal 1-month after operation. In 2 cases with vocal cord carcinoma at the early stage, the functions and construction of throat were retained and no recurrence was founded after 6-12 month postoperatively. CONCLUSION: The laryngeal endoscopic system is valuable in treating laryngeal pathological regions and early stage carcinoma for its minimally invasion, wide operative field, good illuminative degree and normal construction and function reserved.


Asunto(s)
Enfermedades de la Laringe/cirugía , Neoplasias Laríngeas/cirugía , Laringoscopía , Procedimientos Quirúrgicos Mínimamente Invasivos , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Papiloma/cirugía , Estudios Retrospectivos
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