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1.
Heliyon ; 9(5): e16065, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206043

RESUMO

With the emergence of various filtering technologies, the radar jamming efficiency of the technology based on radar cross section is ever lower, therefore cannot meet military requirements. In this context, the jamming technology based on attenuation mechanism has been developed and plays an increasingly important role in disturbing radar detecting. Magnetically expanded graphite (MEG) has excellent attenuation efficiency because it can cause dielectric loss as well as magnetic loss. Moreover, MEG features good impedance matching, which makes more incidence of electromagnetic waves into the material; and its multi-layer structure is conducive for electromagnetic wave reflection and absorption. In this work, the structure model of MEG was established by analyzing the layered structure of expanded graphite (EG) and the dispersion of intercalated magnetic particles. The electromagnetic parameters of thus-modeled MEG were calculated based on the equivalent medium theory; and effects of EG size, magnetic particle type and volume fraction on the attenuation performance were studied by the variational method. It is indicated that MEG with 500-µm diameter has the best attenuation effect and the highest increment of absorption cross section appears at 50% volume fraction of the magnetic particles at 2 GHz. The imaginary part of complex permeability of the magnetic material has the most significant influence on the attenuation effect of MEG. This study provides guidance for the design and application of MEG materials in disturbing radar detecting field.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1540-1547, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627437

RESUMO

OBJECTIVE: To analyze the disease types, clinical manifestations, efficacy and outcome of JAK2 V617F and BCR-ABL double-mutant myeloproliferative neoplasms (MPN), and provide a reference for the diagnosis, treatment and prognosis of MPN. METHODS: The clinical characteristics, diagnosis, therapeutic efficacy and outcome of JAK2 V617F and BCR-ABL double-mutant MPN were analyzed comprehensitively by combining a clinical case diagnosed and treated in our hospital with literature cases from CNKI and PubMed databases. RESULTS: A total of 38 related literatures were retrieved from the two databases by searching "JAK2 V617F" and "BCR-ABL" as key words from 1990 to 2019, and 59 cases were involved. Among all the 60 cases, 41 were males (68.3%) with a median age of 61 (32-77) years old, while 19 were females (31.7%) with a median age of 58 (21-82) years old. The BCR-ABL fusion gene and JAK2 V617F mutation were found simultaneously in 21 cases (35%), 19 cases (31.7%) with JAK2 V617F mutation were found during the treatment of Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). Ph+CML was detectable in 20 cases (33.3%) during the treatment of JAK2 V617F mutation positive MPN. Polycythemia vera (PV) was the most common MPN coexisting with CML (30%), followed by essential thrombocythemia (ET) (26.7%) and primary myelofibrosis (PMF) (21.7%). In addition, there were 13 cases (21.7%) not classified in the literature. Among the 60 cases, 35 CML patients were clearly staged, including 31 in the chronic phase, 3 in the accelerated phase, and 1 in the blast crisis phase. As for the subtypes of BCR-ABL fusion gene, there were 30 cases with clear classification, including 28 cases of p210, 1 case of p190 and 1 case of p230. CONCLUSION: As cases of BCR-ABL and JAK2 V617F double-mutant MPN are reported, simultaneous detection of JAK2 V617F mutation and BCR-ABL fusion gene in MPN patients is necessary to avoid misdiagnosis and missed diagnosis.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Trombocitemia Essencial , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Proteínas de Fusão bcr-abl/genética , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/genética , Adulto Jovem
3.
Talanta ; 232: 122499, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074451

RESUMO

In this work, ZnO nanorods (ZnO NRs) with different sizes were hydrothermally grown on the surface of Whatman filter paper for the fabrication of a microfluidic paper-based device (µPAD) for the simultaneous detection of glucose and uric acid. As dual enzymatic reaction was employed for the colorimetric detection in this µPAD, the presence of ZnO NRs promoted the enzyme immobilization thus significantly enhancing the colorimetric signal. The coffee ring effect was effectively conquered by the uniform distribution of ZnO NR as well as a specialized double-layered µPAD design. Meanwhile, two color indicators with distinct colors were used to provide complementary results to better quantify the concentration of the analytes by naked eye. As a result, two linear calibration curves were obtained for the detection of glucose (0.01-10 mmol L-1) and uric acid (0.01-5 mmol L-1), along with a LOD of 3 µmol L-1 for glucose and 4 µmol L-1 for uric acid, respectively. The practical usefulness of the proposed µPAD was further validated by the simultaneous analysis of glucose and uric acid in serum samples and urine samples.


Assuntos
Técnicas Analíticas Microfluídicas , Nanotubos , Óxido de Zinco , Microfluídica , Papel
4.
Phys Rev Lett ; 126(1): 015702, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480773

RESUMO

Mixtures of ammonia and water are major components of the "hot ice" mantle regions of icy planets. The ammonia-rich ammonia hemihydrate (AHH) plays a pivotal role as it precipitates from water-rich mixtures under pressure. It has been predicted to form ionic high-pressure structures, with fully disintegrated water molecules. Utilizing Raman spectroscopy measurements up to 123 GPa and first-principles calculations, we report the spontaneous ionization of AHH under compression. Spectroscopic measurements reveal that molecular AHH begins to transform into an ionic state at 26 GPa and then above ∼69 GPa transforms into the fully ionic P3[over ¯]m1 phase, AHH-III, characterized as ammonium oxide (NH_{4}^{+})_{2}O^{2-}.

5.
Analyst ; 146(3): 1016-1022, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33295353

RESUMO

In recent years, α-glucosidase inhibitors (AGIs) have played a significant role in the treatment of type II diabetes (T2D), so it is necessary to develop a reliable and sensitive method to find new AGIs. Herein, we establish a novel method based on fluorescent carbon nitride nanoparticles (CNNPs) for the sensitive detection of the activity of α-glucosidase (α-glu) and the screening of its inhibitors. A CNNP-based fluorescent probe is synthesized from green raw materials, urea and lysine, by a one-pot method. In the presence of α-glu, the substrate 4-nitrophenyl-α-d-glucopyranoside (pNPG) is hydrolyzed to generate 4-nitrophenol (pNP), leading to the fluorescence (FL) quenching of CNNPs due to the inner filter effect (IFE). On the other hand, the activity of α-glu is inhibited after the addition of AGIs, which turns on the FL of CNNPs. In this way, the detection of α-glu activity and the screening of AGIs are achieved. The linear range is 1.25-10.00 U L-1 with a limit of detection as low as 0.17 U L-1 and the IC50 values of two typical inhibitors (gallic acid and acarbose) are 813 µM and 465 µM, respectively. The CNNP probe is further applied for the determination of α-glu activity in human serum samples with satisfactory results.


Assuntos
Diabetes Mellitus Tipo 2 , Nanopartículas , Carbono , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Corantes Fluorescentes , Humanos , Nitrilas , alfa-Glucosidases
6.
Talanta ; 221: 121668, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33076174

RESUMO

Rapid and sensitive diagnosis of bacterial infections at early stage is of great significance for food safety monitoring as well as clinical treatment. Herein, we construct a surface-enhanced Raman scattering (SERS) nanoprobe based on M13 phages for the selective detection and inactivation of Staphylococcus aureus (S. aureus). M13 phage with specific S. aureus-binding heptapeptide displayed on the N-terminal of pIII protein is selected from phage display peptide library. The S. aureus-specific SERS probe is thus constructed by in situ growth of gold nanoparticles (AuNPs) on M13 phage surface, followed by modification with 5,5-dithiobis-(2-nitrobenzoic acid) (DTNB) as SERS active molecule. Upon the addition of this SERS probe, M13 phage selectively binds with S. aureus to induce anchoring of AuNPs on S. aureus surface, and the SERS probe-labeled S. aureus cells are collected by centrifugation for SERS detection. For the quantification of S. aureus, a linear range of 10-106 cfu mL-1 is achieved in aqueous medium. It is further demonstrated by spiking recovery in soft drinks. Furthermore, this SERS probe exhibits bactericidal capabilities towards S. aureus, which shows promising potential to serve as a multifunctional platform for simultaneous detection and inactivation of S. aureus.


Assuntos
Ouro , Nanopartículas Metálicas , Bacteriófago M13 , Análise Espectral Raman , Staphylococcus aureus
7.
Oncol Lett ; 20(4): 21, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32774494

RESUMO

Clinical trials of chimeric antigen receptors (CARs) targeting CD19 have produced impressive results in hematological malignancies, including diffuse large B-cell lymphoma (DLBCL). However, a notable number of patients with DLBCL fail to achieve remission after CD19 CAR T-cell therapy and may therefore require a dual targeted CAR T-cell therapy. A 31-year-old man with refractory DLBCL was assessed in the present case report. The patient was treated with sequential infusion of single CD19 CAR T cells followed by dual CD19/CD22-targeted CAR T cells. The outcome was that the patient achieved partial remission after the first single CD19 CAR T-cell infusion and complete remission after the dual CD19/CD22-targeted CAR T-cell infusion. Grade 1 cytokine release syndrome (CRS) was observed after the single CD19 CAR T-cell infusion, while grade 3 CRS and hemophagocytic syndrome were observed after the dual targeted CAR T-cell infusion, but these adverse effects alleviated after the treatments. To the best of our knowledge, the present case report is the first to describe the successful application of dual CD19/CD22-targeted CAR T-cell therapy for the treatment of refractory DLBCL. The report suggests that dual CD19/CD22-targeted CAR T-cell therapy may represent a promising option for the treatment of refractory DLBCL; however, caution should be taken due to potential CRS development.

8.
Proc Natl Acad Sci U S A ; 117(24): 13374-13378, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482874

RESUMO

Molecular hydrogen forms the archetypical quantum solid. Its quantum nature is revealed by behavior which is classically impossible and by very strong isotope effects. Isotope effects between [Formula: see text], [Formula: see text], and HD molecules come from mass difference and the different quantum exchange effects: fermionic [Formula: see text] molecules have antisymmetric wavefunctions, while bosonic [Formula: see text] molecules have symmetric wavefunctions, and HD molecules have no exchange symmetry. To investigate how the phase diagram depends on quantum-nuclear effects, we use high-pressure and low-temperature in situ Raman spectroscopy to map out the phase diagrams of [Formula: see text]-HD-[Formula: see text] with various isotope concentrations over a wide pressure-temperature (P-T) range. We find that mixtures of [Formula: see text], HD, and [Formula: see text] behave as an isotopic molecular alloy (ideal solution) and exhibit symmetry-breaking phase transitions between phases I and II and phase III. Surprisingly, all transitions occur at higher pressures for the alloys than either pure [Formula: see text] or [Formula: see text] This runs counter to any quantum effects based on isotope mass but can be explained by quantum trapping of high-kinetic energy states by the exchange interaction.

9.
Phys Rev Lett ; 122(19): 199602, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144972
10.
Phys Rev Lett ; 119(6): 065301, 2017 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-28949614

RESUMO

In situ high-pressure low-temperature high-quality Raman data for hydrogen and deuterium demonstrate the presence of a novel phase, phase II^{'}, unique to deuterium and distinct from the known phase II. Phase II^{'} of D_{2} is not observed in hydrogen, making it the only phase that does not exist in both isotopes and occupies a significant part of P-T space from ∼25 to 110 GPa and below 125 K. For H_{2}, the data show that below 30 K the transition to phase II happens at as low as 73 GPa. The transformation from phase II to III commences at around ∼155 GPa and is completed by 170 GPa with the average pressure of ∼160 GPa being slightly higher than previously thought. The updated phase diagrams of H_{2} and D_{2} demonstrate the difference between the isotopes at low temperatures and moderate pressures, providing new information on the phase diagrams of both elements.

11.
J Tradit Chin Med ; 31(1): 7-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21563498

RESUMO

OBJECTIVE: To observe the effects of Lüfukang Capsules on arrhythmia induced by ligation of coronary artery in dogs. METHODS: Thirty dogs were randomly divided into 5 groups, the model group administrated with equal volume of distilled water, the positive control group administrated with Wenxin Granules, and the small, medium and large dosage LFKC groups, 6 dogs in each group. Thirty minutes after medication, electrocardiogram was conducted and the time of arrhythmia occurrence, times of ventricular premature beat (VP), and incidence rates of ventricular tachycardia (VT) and ventricular fibrillation (VF) were recorded in the model dogs with arrhythmia induced by ligation of coronary artery. RESULTS: Compared with the model group, the occurrence time of arrhythmia induced by the coronary artery ligation in the medium and large LFKC groups was significantly delayed (20.45 +/- 9.10 and 19.92 +/- 3.78, respectively, both P < 0.05). The frequency of VP in the medium and large LFKC groups was also significantly decreased (8.17 +/- 6.62 and 3.83 +/- 2.79, respectively, both P < 0.01). CONCLUSION: LFKC has anti-arrhythmic effects for the experimental arrhythmia induced by the ligation of coronary artery in dogs.


Assuntos
Antiarrítmicos/administração & dosagem , Arritmias Cardíacas/tratamento farmacológico , Vasos Coronários/cirurgia , Medicamentos de Ervas Chinesas/administração & dosagem , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/cirurgia , Vasos Coronários/efeitos dos fármacos , Modelos Animais de Doenças , Cães , Feminino , Humanos , Ligadura/efeitos adversos , Masculino
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