Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Chem Commun (Camb) ; 60(10): 1285-1288, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38197129

RESUMO

Herein, we reported an efficient indium catalyzed dithianyl-alkyne metathesis (DAM) reaction. This strategy allows for the formation of a new C-C double bond and valuable C-S bonds during the metathesis event, and was successfully applied to the synthesis of diverse vinyl dithianyl substituted organic molecules.

3.
Iran J Immunol ; 20(1): 129-134, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36934323

RESUMO

Several cases of the hemolytic disease of the fetus and newborn (HDFN) caused by immunoglobulin G (IgG) anti-M antibodies have been reported, in which almost all the HDFN-associated anti-M were warmly reacting. Here we report two cases of severe HDFN associated with cold-reacting IgG anti-M. In both cases, pregnancy was terminated, in weeks 33 and 23 respectively, due to a diagnosis of fetal growth retardation (FGR). To our knowledge, these are the most severe HDFN cases caused by cold-reacting IgG anti-M.


Assuntos
Antígenos de Grupos Sanguíneos , Eritroblastose Fetal , Gravidez , Feminino , Recém-Nascido , Humanos , Imunoglobulina G , Eritroblastose Fetal/diagnóstico , Eritroblastose Fetal/etiologia , Feto
4.
Nanoscale Res Lett ; 17(1): 118, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36484877

RESUMO

Structure has been considered to play an important role in photocatalytic performance of the semiconductors, but the intrinsic factors were rarely revealed. Herein, ZnO nanomaterials in the structures of thin film, nanowire array and nanosheet array were synthesized, and their structural characteristics, optical properties, photocurrent response and photocatalytic efficiency were compared with each other for illustrating the issue. The photoluminescence intensity decreased in the order of nanosheets, thin film and nanowires for improved lifetime of the photoexcited charges. The absorption of the nanosheets and nanowires improved obviously in the visible range with a redshift of the absorption edge than that of the thin film. The nanowires possessed the highest response current of 82.65 µA at a response time of 2.0 ms in a sensitivity of 87.93 at the light frequency of 1 Hz, and gained the largest catalytic efficiency of 2.45 µg/cm2 h for the methylene blue degradation in UV light. Nevertheless, the improvement of catalytic efficiency of the nanosheets (up to 42.4%) was much larger than that of nanowires (5.7%) and thin film (2.6%) for the Au coating. The analysis revealed that the photocatalytic efficiency of the ZnO nanomaterials was modulated by the structure as it contained different surface area, roughness, defect and doping states, vacancies, polar and non-polar crystalline faces, which would provide structural design of semiconductor nanomaterials for the photoelectric and photocatalytic applications.

5.
Opt Express ; 30(5): 6700-6712, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299449

RESUMO

Magneto-optical (MO) properties of the bilayed Au/BIG and trilayered Au/BIG/Au magneto-plasmonic crystals (MPCs) were analyzed by the finite-difference time-domain method. In contrast to the low deflection angle and transmission of the smooth thin film, all the heterostructures with perforated holes in the top Au film displayed a similar trend with two strong resonant bands in Faraday rotation and transmittance in the near infrared wavelength range. The bands and electric distribution relative to the component and hole structure were revealed. The MPC with plasmonic hexagonal holes was found to own superior Faraday effects with distinctive anisotropy. The evolution of the resonant bands with the size and period of hexagonal holes, the thickness of different layers, and the incident light polarization was illustrated. The Faraday rotation of the optimized bilayed and trilayered hexagonal MPCs was improved 15.3 and 17.5 times, and the transmittance was enhanced 12.1 and 11.1 folds respectively at the resonant wavelength in comparison to the continuous Au/BIG film, indicating that the systems might find potential application in MO devices.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-939705

RESUMO

OBJECTIVE@#To analyze the molecular polymorphisms of CD36 among 58 blood donors with CD36 deficiency and compare with CD36 positive controls.@*METHODS@#A total of 58 donors with CD36 deficiency during a screening conducted in the laboratory from September 2019 to December 2020 were enrolled as the test group, including 39 males and 19 females, while 120 platelet donors with CD36 positive were randomly selected as the controls, including 76 males and 44 females. All of the subjects were Han nationality. The PCR-SBT method was used to detect coding region of CD36 gene, and molecular mutations were compared with those CD36 positive controls.@*RESULTS@#Among the 58 donors with CD36 deficiency, mutations appears in 32 individuals. The detection rate for type I was 71.43% (5/7), and type II was 51.92% (27/52), while among the 120 controls, mutations appears in 12 donors (10%). In the CD36 antigen-deficient donors, 16 variations were found, in which 329-330 del AC with the highest frequency accounted for 20.69%, followed by 1228-1239 del ATTGTGCCTATT(15.52%) and 1156 C>T(10.34%). Two variations, 198-205 del GATCTTTG and 220 C>T, led to premature termination of translation; four mutations, 329-330 del AC, 560 ins T, 1011-1049 39bp dupl and 1343-1344 ins TCTT, caused translation frame shift; 1228-1239 del ATTGTGCCTATT led to deletion of four amino acids (Ile-Val-Pro-Ile) at sites 410-413 of the peptide chain. The 1140 T>A and 1275 G>A were synonymous mutations, and the other 7 mutations resulted in the substitution of single nucleotide. The platelet expression in the donors of CD36 positive with 329-330 del AC or 1228-1239 del ATTGTGCCTATT mutation (heterozygote) was lower than those CD36 positive individuals without mutations (homozygote).@*CONCLUSION@#Multiple gene mutations in the CD36 coding region may cause CD36 deficiency, and the heterozygous individuals with mutations may lead to CD36 antigen reduction or deletion. Mutation is not detected in 44.83% of CD36 deficient individuals, there may be some other reasons for the CD36 antigen deficiency.


Assuntos
Feminino , Humanos , Masculino , Doadores de Sangue , Transtornos Plaquetários/metabolismo , Plaquetas/metabolismo , Antígenos CD36/metabolismo , Doenças Genéticas Inatas
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-936358

RESUMO

OBJECTIVE@#To investigate the effect of dihydromyricetin (DHM) on cardiac insufficiency in diabetic rats and explore the underlying mechanism.@*METHOD@#Twenty-four male SD rats were randomized equally into normal control group, type 2 diabetes (T2DM) group fed on a high-glucose and high-fat diet for 6 weeks with low-dose streptozotocin (STZ) injection, metformin (MET) group with daily intragastric administration of MET (150 mg/kg) for 8 weeks after T2DM modeling, and dihydromyricetin (DHM) group with daily intragastric administration of DHM (250 mg/kg) for 8 weeks after modeling. The levels of fasting blood glucose, low density lipoprotein (LDL-C), triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL-C) and glycosylated hemoglobin (HbA1c) of the rats were measured, and plasma levels of insulin and high mobility group protein-1 (HMGB1) were detected with ELISA. The cardiac function of the rats was assessed using color echocardiography, ECG was measured using a biological signal acquisition system, and myocardial pathology was observed with HE staining. The protein expressions of HMGB1, nuclear factor-κB (NF-κB) p65 and phospho-NF-κB p65 (p-NF-κB p65) in the myocardial tissue were detected using Western blotting.@*RESULTS@#Compared with the control group, the rats in T2DM group showed significant anomalies in cardiac function after modeling with significantly increased plasma HMGB1 level and expressions of HMGB1, NF-κB p65 and p-NF-κB p65 proteins in the myocardial tissue (P < 0.05 or 0.01). Treatment with DHM significantly improved the indexes of cardiac function of the diabetic rats (P < 0.05 or 0.01), decreased plasma HMGB1 level and down-regulated the protein expressions of HMGB1 and p-NF-κB p65 in the myocardial tissue (P < 0.05 or 0.01).@*CONCLUSION@#DHM treatment can improve cardiac function in diabetic rats possibly by down-regulation of HMGB1 and phospho-NF-κB p65 expressions in the myocardium.


Assuntos
Animais , Masculino , Ratos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Flavonóis , Proteína HMGB1 , Insuficiência Cardíaca , Metformina/uso terapêutico , NF-kappa B/metabolismo , Ratos Sprague-Dawley
8.
Org Lett ; 23(12): 4834-4837, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34076451

RESUMO

A formal (4 + 1)-cycloaddition of vinylcyclopropanes and Et2SiH2 to afford 3,4-disubstituted silolanes is reported. The reaction sequence commences with the known B(C6F5)3-catalyzed alkene hydrosilylation with dihydrosilanes. Cleavage of the remaining Si-H bond in the hydrosilylation product assisted by B(C6F5)3 leads to formation of a cyclopropane-stabilized silylium ion. The activated cyclopropane ring is then opened by the in situ-generated borohydride accompanied by ring closure to the silolane. The diastereoselectivity is rationalized by a mechanistic model.

9.
Environ Sci Pollut Res Int ; 28(14): 17636-17647, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33400121

RESUMO

In this work, copper hexacyanocobaltate was electro-deposited at amino-graphene-coated indium-tin-oxide glass to form multifunctional heterogeneous catalyst (CuCoG/ITO), which was confirmed by field emission scanning microscope, infrared spectra, X-ray diffraction, and electro-chemistry techniques. A novel heterogeneous photo-electro-Fenton-like system was established using CuCoG/ITO as an air-diffusion electrode, in which hydrogen peroxide (H2O2) and hydroxyl radical (•OH) could be simultaneously generated by air O2 reduction. The productive rate of •OH could reached to 70.5 µmol h-1 at - 0.8 V with 300 W visible light irradiation at pH 7.0, 0.1 M PBS. Levofloxacin could be quickly degraded at CuCoG/ITO during heterogeneous photo-electro-Fenton process in neutral media with a first-order kinetic constant of 0.49 h-1.


Assuntos
Grafite , Poluentes Químicos da Água , Catálise , Cobre , Eletrodos , Peróxido de Hidrogênio , Levofloxacino , Oxirredução , Poluentes Químicos da Água/análise
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1003975

RESUMO

【Objective】 To analyze the blood samples sent by hospitals in Shenzhen to solve ABO cross-match incompatibility during 2011 to 2020, so as to find corresponding solutions to improve the efficacy of blood transfusion. 【Methods】 The clinical data of 1 770 cases of cross-match incompatibility in our laboratory from January 2011 to December 2020 were collected and reviewed. The causes of cross-match incompatibility were analyzed, the types of unexpected antibodies were determined. The overall incidence of antibodies was evaluated by statistical method of classified variables. The safety of blood transfusion was safeguarded by ABO homotype plus cross-matching compatibility. 【Results】 1) The 1 770 samples, presenting cross-matching incompatibility, involved 956 patients. The average number of cross-matching per patient from 2011 to 2015 was 1.32(307/232), which increased from 1.27(103/81) in 2016 to 2.23(286/128) in 2018, and remained stable in 2019 and 2020. 2) Among 956 patients, auto-and/or allo-antibody in plasma were yielded in 90.38%(864/956), including auto-antibody plus alloantibody in 42.26%(404/956), solo auto-antibody in 20.71%(198/956) and solo allo-antibody in 27.41%(262/956). Up to 20 kinds of specific allo-antibodies were detected, belonging to 8 blood groups. Among them, 70.82%(551/778) were Rh blood group, such as anti-E(37.15%)>anti-c(20.95%)>anti-C(5.27%)=anti-e(5.27%)>anti-D(2.19%), followed by MNS [11.40%(112/778)], Kidd [5.66%(44/778)], Leiws [3.21%(25/778)], Duffy [1.80%(14/778)], Diego [1.03%(8/778)], P1 [0.39%(3/778)] and H [0.26%(2/778)]. 3) 86%(37/43) of multiple transfusion recipients, aged below 20 years old, were thalassemia, and 1-4 kinds of allo- and/or auto-antibody were yielded. 【Conclusion】 The cross-matching incompatibility were mainly caused by allo- and/or auto-antibodies, which may be induced by blood transfusion, pregnancy or autoimmune diseases such as autoimmune hemolytic anemia.Those suspicious blood samples in clinical should be sent to blood group reference laboratory for further determination, in order to ensure the safety and efficacy of blood transfusion.

11.
Org Lett ; 22(18): 7383-7386, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32903017

RESUMO

A hydrosilylation of vinylcyclopropanes (VCPs) catalyzed by the strong boron Lewis acid B(C6F5)3 is reported. For the majority of VCPs, little or no ring opening of the cyclopropyl unit is observed. Conversely, for VCPs with bulky R groups, such as ortho-substituted aryl rings or branched alkyl residues, ring opening is the exclusive reaction pathway. This finding is explained by the thwarted hydride delivery to a sterically shielded, ß-silicon-stabilized cyclopropylcarbinyl cation intermediate.

12.
Chem Commun (Camb) ; 56(30): 4188-4191, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32167108

RESUMO

A highly chemoselective platinum-catalyzed mono-lateral diboration of dialkynylsilanes for the construction of silicon-tethered alkynyl diborylalkenes is described, in which tris(4-methoxyphenyl)phosphine was found to be an effective ligand for the cis-addition of diboron agents to the silicon-tethered alkynes, and the chiral ligand (AFSi-Phos)-mediated diboration of dialkynylsilanes resulted in the desymmetric construction of silicon-stereogenic centers with promising enantioselectivity.

13.
Chem Sci ; 12(2): 569-575, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34163787

RESUMO

A trityl-cation-initiated annulation of benzyl-substituted vinylcyclopropanes (VCPs) with hydrosilanes is reported. Two Si-C(sp3) bonds and one C(sp2)-C(sp3) bond are formed in this process where an intramolecular 6-endo-tet Friedel-Crafts alkylation of a silylium-ion-activated cyclopropane ring is the rate-determining key step. The reaction mechanism is proposed based on computations and is in agreement with experimental observations. The new reaction leads to an unprecedented silicon-containing 6/6/5-fused ring system. A phenethyl-substituted VCP derivative yields another unknown tricycle having 6/6/6 ring fusion by reacting in a related but different way involving a 6-exo-tet ring closure.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-818944

RESUMO

Objective To investigate the Blomia tropicalis breeding status in the ground dust rice collected in Haikou City. Methods Totally 17 samples of ground dust rice were collected from 10 sampling sites in Haikou City. Then 10 g of dust rice was taken from each individual sample for isolation of the mites that were made of slide specimen, and the mites were identified and classified under a microscope. Results B. tropicalis mites were found in all the 17 samples with the detection rate of 100%. A total of 1 176 heads of B. tropicalis were isolated, with an average breeding density of 6.91 heads/g. Conclusion B. tropicalis breeding status is severe in Haikou City. The effective measures should be taken to prevent and control the harm associated with B. tropicalis contamination.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-817759

RESUMO

@#【Objective】To assess the difference in volume load between different blood pressure control levels in outpatients with hypertension. To investigate the effect of clinical factors on volume load in outpatients with hypertension. To analyze the clinical baseline characteristics and use of antihypertensive drugs in outpatients with hypertension. 【Methods】 A total of 514 outpatients with hypertension were included from July to November 2017. Clinical indicators including gender,age,height,weight,years of hypertension,blood pressure levels,treatment options for hypertension and comorbidities of these patients were recorded. The body volume load was evaluated by detecting the ratio of extracellular fluid(ECW)to total body water(TBW)using a Bioimpedance Analyzer. Whole body ECW/TBW≥0.39 was defined as high volume load. The effects of clinical factors on the volume load of hypertensive patients and whether there was a difference in volume load between different antihypertensive therapy were analyzed. 【Results】The blood pressure compliance rate of outpatients with hypertension was 15.37% ,which was still very low. Male patients had lower blood pressure compliance rate than female patients. Blood pressure was more difficult to control in patients with older age ,higher body mass index (BMI),higher waist-to-hip ratio(WHR)or longer duration of hypertension. The higher the blood pressure grading,the higher the proportion of combination medication. Diuretics were still the most widely used antihypertensive drugs. Age ,gender and different hypertension grades were the main factors affecting the volume load of hypertensive patients. Volume load was higher in female,older or higher systolic blood pressure(SBP)patients. Among them,age was the most important factor affecting the volume load of hypertensive patients.【Conclusion】The blood pressure compliance rate of outpatients with hypertension was still low. Effectively reducing the volume load was one of the important means to control blood pressure,which was more important in female,older or higher SBP patients.

16.
ACS Appl Mater Interfaces ; 10(35): 29909-29917, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30047262

RESUMO

It is highly challenging to achieve an optically deformable polymer with good controllability, stability, and self-healability for fabricating an optically controlled microrobotics. Here, we present a photo-responsive self-healing supramolecular assembly cross-linked by 3,3',5,5'-azobenzenetetracarboxylic acid (t-Azo) enabling the controllable and stable deformation. The network (PAA-u) of polyacrylic acid (PAA) grafted with 2-ureido-4[1 H]-pyrimidinone (UPy) is formed via multiple intermolecular hydrogen bonds (H-bonds) between UPy and t-Azo moieties. Molecular H-bonds stabilize the cis-isomer, enables stress transfer at the interface, and also contributes to fast healability. The PAA-u/t-Azo assembly shows a green-light-induced bending deformation, which recovers its shape under the irradiation of UV light. On the basis of this controllable and reversible deformation, the PAA-u/t-Azo "hand" realizes reversible light-driven grabbing and releasing of an object by optimizing bending and recovery. The assembly also shows a fast and excellent self-healing performance irradiated by green light during deformation. The multiple-H-bonding-cross-linked assembly with stable deformation and fast self-healability can be used for the development of a multitude of advanced microrobotics.

17.
Nanoscale ; 10(34): 15989-15997, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29856449

RESUMO

We describe sonication-assisted liquid-phase exfoliation of rhombohedral germanium telluride (α-GeTe) to obtain a good dispersion of α-GeTe nanosheets in ethanol. The thickness of the α-GeTe nanosheets is dependent on the exfoliation conditions, and few-layer α-GeTe nanosheets of 2-4 layers and even monolayer α-GeTe were obtained. We use first-principles calculations to investigate the structural, electronic, and optical properties of monolayer and bulk α-GeTe and compare the optical band gap of centrifugally fractionated α-GeTe nanosheet dispersions with the computational predictions. We demonstrate that few layer α-GeTe nanosheets are purified selectively through centrifugation, and they exhibit high sensitivity to Fe3+. The scalable production of two-dimensional α-GeTe nanosheets can be used in the future optoelectronic industry.

18.
Chem Commun (Camb) ; 54(22): 2727-2730, 2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29411784

RESUMO

A fluorine-doped reduced graphene oxide (F-rGO), predominantly in the form of CF2 groups, was synthesized using the reduced-graphene-oxide precursor devoid of residual hydroxyl and carboxyl groups through a solvothermal process. The vacancies and defects accompanying the formation of the highly stable and electrochemically inert CF2 groups contribute to the excellent cycling stability of F-rGO, when it is applied as the anode material in a lithium-ion battery.

19.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(3): 343-345, 2018 Jun 05.
Artigo em Chinês | MEDLINE | ID: mdl-31544424

RESUMO

OBJECTIVE: To investigate the Blomia tropicalis breeding status in the ground dust rice collected in Haikou City. METHODS: Totally 17 samples of ground dust rice were collected from 10 sampling sites in Haikou City. Then 10 g of dust rice was taken from each individual sample for isolation of the mites that were made of slide specimen, and the mites were identified and classified under a microscope. RESULTS: B. tropicalis mites were found in all the 17 samples with the detection rate of 100%. A total of 1 176 heads of B. tropicalis were isolated, with an average breeding density of 6.91 heads/g. CONCLUSIONS: B. tropicalis breeding status is severe in Haikou City. The effective measures should be taken to prevent and control the harm associated with B. tropicalis contamination.


Assuntos
Cruzamento , Ácaros , Oryza , Animais , China , Parasitologia de Alimentos , Oryza/parasitologia , Densidade Demográfica
20.
RSC Adv ; 8(31): 17325-17333, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35539238

RESUMO

Amorphous red phosphorus/pyrolyzed bacterial cellulose (P-PBC) free-standing films are prepared by thermal carbonization and a subsequent vaporization-condensation process. The distinctive bundle-like structure of the flexible pyrolyzed bacterial cellulose (PBC) matrix not only provides sufficient volume to accommodate amorphous red-phosphorus (P) but also restricts the pulverization of red-P during the alternate lithiation/delithiation process. When the mass ratio of raw materials, red-P to PBC, is 70 : 1, the free-standing P-PBC film anode exhibits high reversible capacity based on the mass of the P-PBC film (1039.7 mA h g-1 after 100 cycle at 0.1C, 1C = 2600 mA g-1) and good cycling stability at high current density (capacity retention of 82.84% after 1000 cycles at 2C), indicating its superior electrochemical performances.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...