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1.
Angew Chem Int Ed Engl ; 63(21): e202400769, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38544401

RESUMO

Generating circularly polarized luminescence (CPL) with simultaneous high photoluminescence quantum yield (PLQY) and dissymmetry factor (glum) is difficult due to usually unmatched electric transition dipole moment (µ) and magnetic transition dipole moment (m) of materials. Herein we tackle this issue by playing a "cascade cationic insertion" trick to achieve strong CPL (with PLQY of ~100 %) in lead-free metal halides with high glum values reaching -2.3×10-2 without using any chiral inducers. Achiral solvents of hydrochloric acid (HCl) and N, N-dimethylformamide (DMF) infiltrate the crystal lattice via asymmetric hydrogen bonding, distorting the perovskite structure to induce the "intrinsic" chirality. Surprisingly, additional insertion of Cs+ cation to substitute partial (CH3)2NH2 + transforms the chiral space group to achiral but the crystal maintains chiroptical activity. Further doping of Sb3+ stimulates strong photoluminescence as a result of self-trapped excitons (STEs) formation without disturbing the crystal framework. The chiral perovskites of indium-antimony chlorides embedded on LEDs chips demonstrate promising potential as CPL emitters. Our work presents rare cases of chiroptical activity of highly luminescent perovskites from only achiral building blocks via spontaneous resolution as a result of symmetry breaking.

3.
Heliyon ; 9(11): e21232, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37964835

RESUMO

Background: In this study, the regularity of drug containing borneol proprietary Chinese medicine was mined, to provide reference for the clinical application and new drug research and development of borneol. Methods: The database of proprietary Chinese medicines on Pharmaceutical Intelligence Network was searched for internal and external prescriptions that contained borneols and the diseases they treat. Microsoft Office Excel 2019 and SPSS Modeler 18.0 were used to analyze the properties, flavors, meridians tropisms and association rule analysis of the medicines, and Origin 21.0 software was used to draw the association rules diagram. Results: Among them, 528 prescriptions of internal Chinese patent medicine containing borneol and 387 prescriptions of external Chinese patent medicine were included. The diseases treated by internal prescription were mainly neurological diseases and heart diseases, among which Chinese medicines with higher frequency of compatibility with borneol were bezoar, licorice, cinnabar, musk and scutellaria. The diseases treated by external prescription were mainly physical disabilities, paralysis diseases, sore and ulcer diseases and so on. Among them, menthol, camphor, frankincense, angelica, and carthami flos and so on are the most frequently combined with borneol. Conclusion: The prescription of Chinese patent medicine containing borneol is composed of cold or warm, pungent or bitter Chinese medicine. Internal prescription primarily targets the meridians of the heart, liver, and lungs, and is often combined with sedative, antipyretic and detoxicating drugs to treat stroke, infantile convulsion and angina pectoris. External prescription mainly acts on liver, heart and spleen meridian, and is often combined with drugs for clearing heat, promoting blood circulation and removing blood stasis to treat rheumatic arthralgia syndrome and sore and ulcer diseases.

4.
Front Pharmacol ; 14: 1129125, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089924

RESUMO

Introduction: Vascular cognitive impairment (VCI) is one of the most common types of dementia. Naoxin'an capsule (NXA), a traditional Chinese medicine compound, has been used to treat VCI for a long time in the clinic. Previous studies proved that the NXA capsules could ameliorate the cerebral mitochondrion deficits of VCI animals. This study aimed to investigate the protectiveness of NXA on human brain structure and function in patients with VCI. Methods: In total, 100 VCI patients were enrolled in this 24-week trial and randomly divided into the NXA capsules group (n = 50) and the ginkgo biloba capsules control group (n = 50). Before and after the treatment, cognitive behavior tests and multimodal brain magnetic resonance imaging were analyzed to comprehensively evaluate the effectiveness of NXA treatment on VCI patients after 24 weeks. Results: We found that the NXA group significantly improved overall cognitive ability (Alzheimer's Disease Assessment Scale-Cognitive section, p = 0.001; Mini-Mental Status Examination, p = 0.003), memory (Rey-Osterrieth Complex Figure test, p < 0.001) and executive function (Trail Making Test-A, p = 0.024) performance after treatment compared with the control group. For brain function, the degree of centrality in the left middle frontal gyrus, right postcentral gyrus, and left supplementary motor area increased in the NXA group and decreased in the ginkgo biloba group after treatment. The fractional amplitude of low-frequency fluctuation (fALFF) of the left precentral and right superior parietal gyrus increased, and the fALFF of the right parahippocampal and left inferior temporal gyrus decreased in the NXA group after treatment. For brain structure, the gray matter density of the left postcentral gyrus increased in the NXA group after treatment, and the total volume of white matter hyperintensity showed a decreasing trend but was not statistically significant. Furthermore, the improvement effect of NXA on executive function was associated with changes in brain function. Conclusion: These findings suggest that the NXA capsules improved cognitive performance and multiregional brain function, as well as gray matter structure in the postcentral gyrus.

5.
Hum Brain Mapp ; 44(9): 3926-3938, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37086446

RESUMO

Based on the fluctuations ensembled over neighbouring neurons, blood oxygen level-dependent (BOLD) signal is a mesoscale measurement of brain signals. Intraregional temporal features (IRTFs) of BOLD signal, extracted from regional neural activities, are utilized to investigate how the brain functions in local brain areas. This literature highlights four types of IRTFs and their representative calculations including variability in the temporal domain, variability in the frequency domain, entropy, and intrinsic neural timescales, which are tightly related to cognitions. In the brain-wide spatial organization, these brain features generally organized into two spatial hierarchies, reflecting structural constraints of regional dynamics and hierarchical functional processing workflow in brain. Meanwhile, the spatial organization gives rise to the link between neuronal properties and cognitive performance. Disrupted or unbalanced spatial conditions of IRTFs emerge with suboptimal cognitive states, which improved our understanding of the aging process and/or neuropathology of brain disease. This review concludes that IRTFs are important properties of the brain functional system and IRTFs should be considered in a brain-wide manner.


Assuntos
Mapeamento Encefálico , Encéfalo , Humanos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Cabeça , Imageamento por Ressonância Magnética/métodos , Neurônios
6.
J Pharmacol Toxicol Methods ; 120: 107250, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36627002

RESUMO

OBJECTIVE: To develop a new method for quantitatively analyzing three immunomodulators (thalidomide, lenalidomide and pomadomide) by liquid chromatography tandem mass spectrometry (LC-MS/MS). METHODS: Using thalidomide-d4 as internal standard, the three analytes were separated on Agilent Zorbax SB-C18(2.1 mm × 100 mm, 3.5 µm, Agilent, USA) column and monitored in multiple reactions monitoring mode in Agilent G6460A triple quadrupole mass spectrometer operating in positive ionization mode. The sample was pretreated by protein precipitation using methanol at 3-fold volume to sample. The mobile phase was comprised of 0.1% formic acid in water (phase A) and acetonitrile (phase B) and was delivered in gradient elution program. The flow rate was 0.3 mL/min, and the injection volume was 5 µL. RESULTS: The accuracy and stability of the method are within ±15.0%, and the precision is not >15.0%. The recoveries were 85.04% âˆ¼ 119.07%, and the matrix effect was 73.68% âˆ¼ 116.75%. Specificity, linearity, LLOQ, carry-over and dilution were all in line with the requirements of pharmacopeia and guidelines. The peak concentrations of thalidomide, lenalidomide shows huge inter-individual differences. CONCLUSIONS: This newly developed method was sensitive, simple, and robust and can be used in therapeutic drug monitoring of three immunomodulators in multiple myeloma patients.


Assuntos
Espectrometria de Massas em Tandem , Talidomida , Humanos , Talidomida/química , Cromatografia Líquida/métodos , Lenalidomida , Espectrometria de Massas em Tandem/métodos , Plasma , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes
7.
Micromachines (Basel) ; 13(11)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36363831

RESUMO

Silicon surface barrier detectors (SSBDs) are normally used to detect high-energy particles due to their excellent properties. For better charge collection efficiency (CCE), the SSBD device should be operated at higher reverse voltages, but this can lead to device breakdown. Therefore, we used a PN junction as a guard ring to increase the breakdown voltage of the SSBD. The structures of two SSBD devices are drawn and simulated in this work. Compared with a conventional SSBD (c-SSBD), the use of a PN junction as a guard ring for an SSBD (Hybrid-SSBD) achieves higher breakdown voltages, of over 1500 V under reverse bias. This means that Hybrid-SSBD devices can operate at higher reverse voltages for better charge collection efficiency (CCE) to detect high-energy particles. Then, we simulated the different structure parameters of the Hybrid-SSBD guard rings. Among them, the doping depth and gap width of the guard ring (between the innermost guard ring and the active area) have a greater impact on the breakdown voltage. Finally, for Hybrid-SSBD devices, the optimal characteristics of the guard ring were 1 × 1019 cm-3 doping concentration, 1 µm doping depth, and innermost guard ring width and gap width of 5 µm and 3 µm, respectively.

8.
Micromachines (Basel) ; 13(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36144119

RESUMO

The Silicon Drift Detector (SDD) with square structure is often used in pixel-type SDD arrays to reduce the dead region considerably and to improve the detector performance significantly. Usually, the anode is located in the center of the active region of the SDD with square structure (square-SDD), but the different anode positions in the square-SDD active area are also allowed. In order to explore the effect on device performance when the anode is located at different positions in the square-SDD active region, we designed two different types of square-SDD in this work, where the anode is located either in the center (SDD-1) or at the edge (SDD-2) of its active region. The simulation results of current density and potential distribution show that SDD-1 and SDD-2 have both formed a good electron drift path to make the anode collect electrons. The experimental results of device performance at the temperature range from -60 °C to 60 °C show that the anode current of the two fabricated SDDs both decreased with the decrease of temperature, but their voltage divider characteristics exhibited high stability resistance value and low temperature coefficient, thereby indicating that they could both provide corresponding continuous and uniform electric field at different temperatures. Finally, SDD-1 and SDD-2 have energy resolutions of 248 and 257 eV corresponding to the 5.9 keV photon peak of the Fe-55 radioactive source, respectively. Our experimental results demonstrate that there is no significant impact on the device performance irrespective of the anode positions in the square-SDD devices.

9.
Appl Bionics Biomech ; 2022: 3369743, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465186

RESUMO

Under the background of national fitness, aerobics has become a popular sport. Aerobics has a good fitness effect and is one of the compulsory courses of physical education. But it also puts forward higher requirements for College Aerobics Teaching. The traditional teaching method is no longer applicable. In order to improve the teaching effect of aerobics, this paper puts forward the research of College Aerobics Teaching Method. In this paper, the traditional Aerobics Teaching Methods and the current popular information teaching mode are analyzed in detail. Through the comparison, the traditional aerobics teaching process is too boring to stimulate students' interest. But after the use of information technology teaching, students' self-learning ability has been improved. In the study of the effect of traditional teaching mode and information-based teaching mode, this paper makes relevant experimental investigation. The physical fitness of the experimental group was P > 0.05. There were significant differences in basic physical qualities such as push-ups, rope skipping, and flexibility between the two groups (P < 0.05).The experimental data show that the use of information-based teaching mode is more conducive to students' accurate grasp of action points, and because of the retrospectivity, students can consolidate knowledge and practice themselves more conveniently. The research of this paper promotes the innovation of traditional education, complements and promotes each other with traditional education, and creates greater learning and exploration space for students, in order to contribute to the construction of aerobics courses in colleges and universities.

10.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1114-1119, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285212

RESUMO

Based on the Drugdataexpy and the prescription modern application database, this study explored the formulation regularity of ancient and modern prescriptions for the treatment of sinusitis. The Chinese medicinal prescriptions for the treatment of sinusitis with various syndromes were retrieved from the above databases and the corresponding formulation regularity was investigated by frequency analysis, association rule analysis, and factor analysis. Eighty-seven Chinese medicinal prescriptions were included, involving five syndrome types of sinusitis and 160 Chinese medicine, which were mainly effective in releasing exterior, clearing heat, and tonifying deficiency, and acted on the lung meridian due to cold and warm nature and pungent and bitter flavor or on the spleen meridian due to warm nature and pungent flavor. Seventeen core Chinese medicine were screened out by topological data analysis, including Angelicae Dahuricae Radix, Magnoliae Flos, Glycyrrhizae Radix et Rhizoma, Xanthii Fructus, and Scutellariae Radix. Chinese medicine such as Magnoliae Flos, Angelicae Dahuricae Radix, and Xanthii Fructus were commonly used in the treatment of sinusitis of wind-heat in the lung meridian, while the combination of Glycyrrhizae Radix et Rhizoma, Magnoliae Flos, Angelicae Dahuricae Radix, Chuanxiong Rhizoma, etc. was the key compatibility in treating sinusitis of dampness-heat in the spleen and stomach. Six common factors were extracted from the factor analysis of the above two syndrome types. The findings indicate that the exterior-releasing, heat-clearing, and deficiency-tonifying Chinese medicine with cold and warm nature and pungent flavor are preferential options for the clinical treatment of sinusitis. Treatment should be based on syndrome differentiation and key therapeutic principles should be followed.


Assuntos
Meridianos , Sinusite , Mineração de Dados , Medicina Tradicional Chinesa , Rizoma , Sinusite/tratamento farmacológico
11.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2489-2500, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047095

RESUMO

This study aimed to elucidate the effective components of Shengxian Decoction and its mechanism of action in treating chronic heart failure. Firstly, UHPLC-Q-TOF-MS was established to identify the main chemical constituents in the rat serum after intragastric administration with Shengxian Decoction. Secondly, the absorbed components in serum were then used for the network pharmacology analysis to infer the mechanism and effective components. Targets for constituents in serum were predicted at TCMSP and Swiss-TargetPrediction database. An association network map was drawn by network visualization software Cytoscape 3.6.1. Finally, GO enrichment analysis and KEGG pathway enrichment analysis were carried out for the core target genes. By UHPLC-Q-TOF-MS, 18 prototype compounds were definitely identified, including five compounds from Astragali Radix, four compounds from Anemarrhenae Rhizoma, four compounds from Bupleuri Radix, four compounds from Cimicifugae Rhizoma, and one compound from Platycodonis Radix. Those components of Shengxian Decoction were closely associated with 13 key protein targets, including inflammatory factors, like IL6, IL1 B, TNF, PTGS2, IL10; redox enzymes CAT, HMOX1, and MPO; cardiovascular targets, like VEGFA, NOS3, and NOS2; and transmememial proteins CAV1 and INS. Network pharmacology analysis showed that the 18 compounds could be responsible for the treatment of chronic heart failure by regulating HIF-1 signaling pathways, PI3 K-Akt signaling pathways, cGMP-PKG signaling pathways, cAMP signaling pathways and TNF signaling pathways. This study provided a scientific basis for mechanism and effective ingredients of Shengxian Decoction.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Animais , Cromatografia Líquida de Alta Pressão , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/genética , Ratos , Rizoma , Transdução de Sinais
12.
ACS Nano ; 14(12): 16590-16599, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33044057

RESUMO

With the advent of the 5G era, electronic systems have become more and more powerful, miniaturized, integrated ,and intelligent. The thermal management of electronic systems requires more efficiency and multiple functions for their practical applications, especially for the portable 5G electronic devices of the future, as the undesired heat can cause thermal discomfort or even thermal injury to people who use these electronic devices. Herein, two thermal management strategies based on boron nitride (BN) aerogel films have been proposed and demonstrated for portable devices. First, a flexible BN aerogel film with high porosity (>96%), large specific surface area (up to 982 m2 g-1), and controllable thickness (in the range from 50 to 200 µm) was fabricated via molecular precursor assembly, sublimation drying, and pyrolysis reaction in sequence. The resulting BN aerogel film individuals, serving as a thermal insulation protecting layer in portable electronics, can significantly reduce heat transfer from electronics to skin. Second, BN phase change composite films, made by dipping BN aerogel films into the melts of the organic phase change materials (e.g., paraffin), can effectively cool the portable electronics as the organic phase change materials filled in the aerogel matrix can serve as a smart thermal-regulator to absorb the undesired heat via solid-liquid phase transition. These two typical strategies of the flexible BN aerogel film-directed thermal management could assist in efforts to miniaturize, integrate, and intelligentialize portable 5G electronic devices in the future.

13.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(6): 527-33, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-27324542

RESUMO

OBJECTIVE: To systematically investigate the efficacy and safety of glucocorticoids (GCs) combined with intravenous injection of immunoglobulin (IVIG) in the initial treatment of Kawasaki disease (KD). METHODS: EDLINE Database, PubMed Database, CNKI, Wanfang Data, and VIP Database were searched to collect prospective or retrospective controlled studies on the combination of GCs and IVIG as the initial treatment of KD, which were published up to March 2016. Two investigators independently screened the literature, extracted data, and assessed the quality of the articles included. Then, a Meta analysis was performed using RevMan 5.2 software. RESULTS: A total of 11 articles in English were included, with 7 prospective studies and 4 retrospective studies. The results of the Meta analysis showed that compared with the group using IVIG alone, the combination group had a significantly lower incidence rate of coronary artery lesion (CAL) (OR=0.44, 95%CI 0.23-0.86, P=0.02) and a significantly shorter duration of fever (MD=-1.66, 95%CI -2.32 to -1.01, P<0.00001). The combination group had a significantly lower rate of no response to initial treatment than the IVIG alone group (OR=0.37, 95%CI 0.27-0.51, P<0.00001). The recurrence rate of KD and the incidence rate of adverse events showed no significant differences between the two groups. CONCLUSIONS: GCs combined with IVIG as the initial treatment for KD can reduce the incidence rate of CAL and the rate of no response to initial treatment and shorten the duration of fever, and does not increase the recurrence rate of KD and the incidence rate of adverse events.


Assuntos
Glucocorticoides/administração & dosagem , Imunoglobulinas Intravenosas/administração & dosagem , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Doença da Artéria Coronariana/prevenção & controle , Quimioterapia Combinada , Humanos , Recidiva
14.
Rev Sci Instrum ; 86(8): 086106, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26329246

RESUMO

A high-pressure device with a large cavity was investigated using finite-element analysis. This device is called a double-beveled multilayer stagger-split die, and consists of two supported rings and a multilayer divided body assemblage. Each divided cylinder body has two bevels in the pressurized surface. We simulated the pressure capacity of this device according to different failure criteria. The results were compared with those of a multilayer stagger-split die and belt type die. The bearing capacity of the double-beveled multilayer stagger-split die was more than 7.3 GPa. A group of comparative experiments were conducted to validate the simulated results, and the experimental results show the actual pressure capacity was higher than the simulation.

15.
Rev Sci Instrum ; 86(12): 125113, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26724079

RESUMO

A new high pressure device with a split cylinder was investigated on the basis of the belt-type apparatus. The belt-type die is subjected to excessive tangential tensile stress and the tungsten carbide cylinder is easily damaged in the running process. Taking into account the operating conditions and material properties of the tungsten carbide cylinder, it is divided into 6 blocks to eliminate the tangential tensile stress. We studied two forms of the split type: radial split and tangential split. Simulation results indicate that the split cylinder has more uniform stress distribution and smaller equivalent stress compared with the belt-type cylinder. The inner wall of the tangential split cylinder is in the situation that compressive stress is distributed in the axial, radial, and tangential directions. It is similar to the condition of hydrostatic pressure, and it is the best condition for tungsten carbide materials. The experimental results also verify that the tangential split die can bear the highest chamber pressure. Therefore, the tangential split structure can increase the pressure bearing capacity significantly.

16.
Rev Sci Instrum ; 84(5): 053903, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23742562

RESUMO

A novel ultra-high pressure device, multilayer stagger-split die, has been constructed based on the principle of "dividing dies before cracking." Multilayer stagger-split die includes an encircling ring and multilayer assemblages, and the mating surfaces of the multilayer assemblages are mutually staggered between adjacent layers. In this paper, we investigated the stressing features of this structure through finite element techniques, and the results were compared with those of the belt type die and single split die. The contrast experiments were also carried out to test the bearing pressure performance of multilayer stagger-split die. It is concluded that the stress distributions are reasonable and the materials are utilized effectively for multilayer stagger-split die. And experiments indicate that the multilayer stagger-split die can bear the greatest pressure.

17.
Dalton Trans ; (2): 262-72, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-19089006

RESUMO

Liriodenine (), an active component of the anticancer traditional Chinese medicine (TCM), was isolated from Zanthoxylum nitidum. Its reactions with Pt(II) and Ru(II) afforded three metal complexes: cis-[PtCl2(L)] (), cis-[PtCl2(L)(DMSO)] (), and cis-[RuCl2(L)(DMSO)2].1.5H2O (), the crystal structures of , and were determined by single-crystal X-ray diffraction methods. These complexes were fully characterized by elemental analysis, IR spectrophotometry, 1H and 13C NMR spectroscopies, and ES mass spectrometry. The in vitro cytotoxicity of and complexes against 11 human tumour cell lines was assayed. The metal-based compounds exhibit enhanced cytotoxicity vs. free , suggesting that these compounds display synergy in the combination of metal ions and liriodenine. The binding properties of and its complexes to ct-DNA were investigated through UV-vis, fluorescence, CD spectra, viscosity and agarose gels electrophoretic measurements.


Assuntos
Antineoplásicos/farmacologia , Aporfinas/farmacologia , DNA/metabolismo , Medicina Tradicional Chinesa , Compostos de Platina/química , Compostos de Rutênio/química , Zanthoxylum/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Aporfinas/química , Aporfinas/isolamento & purificação , Linhagem Celular Tumoral , Dicroísmo Circular , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Raízes de Plantas/química , Caules de Planta/química , Compostos de Platina/farmacologia , Compostos de Rutênio/farmacologia
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