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1.
Artigo em Chinês | MEDLINE | ID: mdl-30141606

RESUMO

Objective: To diagnose and treat the first imported active case of Plasmodium knowlesi infection in China. Methods: The clinical information of the patient was collected. Microscopy of blood smear was conducted after Giemsa staining. Genomic DNA was extracted from blood, and PCR was conducted to amplify rDNA. The PCR products were sequenced and analyzed with BLAST Results: The patient returned from a one-week tour in a tropical rain forest in Malaysia. The first disease attack occurred in Guangzhou on Oct. 16, 2014, with fever, shivering and sweating. The patient was initially diagnosed as malaria and hospitalized on Oct. 26, 2014. Microscopic observation revealed typical forms of P. knowlesi in blood smear. The red blood cells became enlarged, with big trophozoites appearing as a ring with dual cores and dark brown malaria pigment. The trophozoites were slightly bigger and thicker than P. falciparum. The schizont had 6-8 merozoites, with obvious brown malaria pigment. PCR resulted in a specific band of 1 099 bp. BLAST analysis showed that the sequence of the PCR product was 99% homologous to P. knowlesi (acession No. AM910985.1, L07560.1 and AY580317.1). The patient was diagnosed as P. knowlesi infection, and was then given an 8-day treatment with chloroquine and primaquine, together with dihydroartemisinin piperaquine phosphate tablet. The patient was discharged after recovery on Oct. 28, 2014. Conclusion: According to the clinical symptoms, epidemiological history and laboratory test, the patient has been confirmed as P. knowlesi infection. It may also be the first active case of knowlesi malaria reported in China.


Assuntos
Malária , Plasmodium knowlesi , Animais , Antimaláricos , Artemisininas , China , Cloroquina , Eritrócitos , Hemeproteínas , Humanos , Microscopia , Reação em Cadeia da Polimerase , Primaquina , Quinolinas , Trofozoítos
2.
Int J Biol Macromol ; 273(Pt 1): 132993, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38862049

RESUMO

Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.

3.
Artigo em Chinês | MEDLINE | ID: mdl-24818403

RESUMO

The epidemiological features of 298 imported malaria cases during 2008-2012 in Guangzhou were analyzed. Among the cases, 169 (56.7%) were falciparum malaria, 106 (35.6%) were vivax malaria, and 23 (7.7%) were unidentified. The proportion of falciparum malaria cases was raising gradually in the last 5 years. Most of the cases were infected in malaria endemic regions of Africa and South-East Asia. Among them, 160 (53.7%) were business services, 78 (26.2%) were export laborers, 20 (6.7%) were peasants, and 18 (6.0%) were others.


Assuntos
Malária/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Int J Biol Macromol ; 245: 125597, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37385310

RESUMO

Galactomannan-based biogums were derived from fenugreek, guar, tara, and carob and consisted of mannose and galactose with different ratios, as well as the implementation of high-value utilization was very significant for sustainable development. In this work, renewable and low-cost galactomannan-based biogums were designed and developed as functional coatings protected on the Zn metal anodes. The molecule structure of galactomannan-based biogums were explored on the effect of anticorrosion ability and uniform deposition behavior through the introduction of fenugreek gum, guar gum, tara gum, and carob gum with different ratios of mannose to galactose as 1.2:1, 2:1, 3:1, and 4:1. The existence of biogum protective layers can reduce the contact area between Zn anodes and aqueous electrolyte to enhance the anticorrosion ability of Zn anodes. Rich oxygen-containing groups in galactomannan-based biogums can coordinate with Zn2+ and Zn atoms to form ion conductivity gel layer and adsorb closely on the surface of Zn metal, which can induce uniform deposition of Zn2+ to avoid dendrite growth. Zn electrodes protected by biogums can cycle impressively for 1980 h with 2 mA cm-2 and 2 mAh cm-2. This work can provide a novel strategy to enhance Zn metal anodes' electrochemical performance, as well as implement the high-value application of biomass-based biogums as functional coatings.


Assuntos
Fabaceae , Zinco , Galactose , Manose , Metais , Eletrodos
5.
ACS Appl Mater Interfaces ; 15(16): 20040-20052, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37043697

RESUMO

The commercial application of high-safety aqueous zinc (Zn) secondary batteries is hindered by the poor cycling life of Zn metal anodes. Here we propose a dendrite growth and hydrogen evolution corrosion reaction mechanism from the binding energy of the deposited crystal plane on the Zn surface and the adsorption energy of H2O molecules on different crystal planes as well as the binding energy of H2O molecules with Zn2+ ions. The biomass-based alkyl polyglucoside (APG) surfactant is adopted as an electrolyte additive of 0.15% to regulate the preferential growth of a parallel Zn(002) plane and enhance the anticorrosion ability of Zn metal anodes. The robust binding and adsorption energies of APG with Zn2+ ions in the aqueous electrolyte and the Zn(002) plane on Zn surface generate a synergistic effect to increase the concentration of Zn2+ ions on the APG-adsorbed Zn(002) plane, endowing the continuous growth of the preferential parallel Zn(002) plane and the excellent anticorrosion capacity. Accordingly, the long-term cycle stability of 4000 h can be achieved for Zn anodes with APG additives, which is better than that with pure ZnSO4 electrolyte. With the addition of APG in the anolyte electrolyte, Zn-I2 full cells display excellent cycling performance (70 mAh g-1 after 20000 cycles) as compared with that without APG additives.

6.
ACS Appl Mater Interfaces ; 13(1): 639-649, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356103

RESUMO

Binders play a crucial role in the development of silicon (Si) anodes for lithium-ion batteries with high specific energy. The large volume change of Si (∼300%) during repeated discharge and charge processes causes the destruction and separation of electrode materials from the copper (Cu) current collector and ultimately results in poor cycling performance. In the present study, we design and prepare hydrogen-bonding cross-linked thiourea-based polymeric binders (denoted CMC-co-SN) in consideration of their excellent binding interaction with the Cu current collector and low cost as well. The CMC-co-SN binders are formed through in situ thermopolymerization of chain-type carboxymethylcellulose sodium (CMC) with thiourea (SN) in the drying process of Si electrode disks. A tight and physical interlocked layer between the CMC-co-SN binder and Cu current collector is derived from a dendritic nonstoichiometric copper sulfide (CuxS) layer on the interface and enhances the binding of electrode materials with the Cu current collector. When applying the CMC-co-SN binders to micro- (∼3 µm) (µSi) and nano- (∼50 nm) (nSi) Si particles, the Si anodes exhibit high initial Coulomb efficiency (91.5% for µSi and 83.2% for nSi) and excellent cyclability (1121 mA h g-1 for µSi after 140 cycles and 1083 mA h g-1 for nSi after 300 cycles). The results demonstrate that the CMC-co-SN binders together with a physical interlocked layer have significantly improved the electrochemical performance of Si anodes through strong binding forces with the current collector to maintain electrode integrity and avoid electric contact loss.

7.
Artigo em Chinês | MEDLINE | ID: mdl-24490402

RESUMO

OBJECTIVE: To understand the status of Enterobius vermicularis infection of children in Huadu District, Guangzhou City so as to provide the evidence for improving the control work. METHODS: In 2012, 24 kindergartens and 24 primary schools were selected as survey sites by the stratified random sampling method and 200 or more children aged below 10 years per site were investigated for the Enterobius vermicularis infection by the cellophane tape method. The relevant influencing factors (environment conditions, sanitary facilities and management system, and health habits of families and individuals) were surveyed with questionnaire, and all the data were analyzed statistically with the Excel software. RESULTS: From September to December, 2012, totally 9 777 children were investigated and 760 ones were detected with Enterobius vermicularis infection (7.77%). With a school as the unit, the highest infection rate reached to 33.82% (69/204). The infection rate in urban areas was 4.63% (195/ 4 213), and the rate in villages was 10.15% (760/5 546) ( chi2 =102.126, P <0.01). The infection rate of preschool children was 3.51% (1 70/4 840) and the rate of school children was 11.95% (590/4 973), and the latter was much higher than the former (chi2 =242.732, P < 0.01). The infection rates of the male and the female were 7.44% (412/5 537) and 8.21% (348/4, 240) respectively ( chi2 = 1.969, P > 0.05). The survey of relevant influencing factors showed that the conditions of the kindergartens were better than those in the primary schools, and the conditions in the urban areas were better than those in the villages. CONCLUSIONS: The Enterobius vermicularis infection of children in Huadu District is high. The control key points should be put on the schools with poor sanitary facilities and environment conditions in villages and urban areas.


Assuntos
Enterobíase/epidemiologia , Criança , China/epidemiologia , Feminino , Humanos , Incidência , Masculino , Inquéritos e Questionários
8.
Artigo em Chinês | MEDLINE | ID: mdl-23236799

RESUMO

OBJECTIVE: To understand the transmission of human parasites in Qushui Village, Yangqing Town, Suixi County, Zhanjing City, Guangdong Province. METHODS: The direct stool smear, floatation, Kato-Katz technique, and hookworm larva culture were used for the parasite infections. The questionnaire survey was applied for the hazards of parasites. The dissections on rats and snails were used for Angiostrongylus cantonensis infection. RESULTS: Five parasites were found and the total infection rate was 10.75%. The infection rates of hookworm (Necator americanus), Ascaris lumbricoides and Trichuris trichiura were 6.07%, 1.87% and 1.87%, respectively, and the infection rates of Enterobius vermicularis and Tyroglyrhus farinae were both 0.47%. The infections were not correlated with the career and age but preferred to males. The densities of infections were slight. The rate of dermatitis caused by hookworm larvae was 69.23%. The infection rates of Angiostrongylus cantonensis were 16.66%, 13.04% and 10.00%, respectively in rats, Achatina fulica and Ampularum crossean. CONCLUSION: The main species of human parasites are nematodes, with hookworm predominately, in Qushui Village, Suixi County. This area is the natural foci of Angiostrongylus cantonensis.


Assuntos
Doenças Parasitárias/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade
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