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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(3): 230-236, 2024 Mar 09.
Artigo em Chinês | MEDLINE | ID: mdl-38432654

RESUMO

Objective: To evaluate the impact of preemptive analgesia with ibuprofen on postoperative pain following the extraction of impacted mandibular third molars in a Chinese population, aiming to provide a clinical reference for its application. Methods: This multicenter, randomized, double-blind, placebo-controlled parallel-group trial was conducted from April 2022 to October 2023 at the Capital Medical University School of Stomatology (40 cases), Beijing TianTan Hospital, Capital Medical University (22 cases), and Beijing Chao-Yang Hospital, Capital Medical University (20 cases). It included 82 patients with impacted mandibular third molars, with 41 in the ibuprofen group and 41 in the control group. Participants in the ibuprofen group received 300 mg of sustained-release ibuprofen capsules orally 15 min before surgery, while the control group received a placebo. Both groups were instructed to take sustained-release ibuprofen capsules as planned for 3 days post-surgery. Pain intensity was measured using the numerical rating scale at 30 min, 4 h, 6 h, 8 h, 24 h, 48 h, and 72 h after surgery, and the use of additional analgesic medication was recorded during days 4 to 6 postoperatively. Results: All 82 patients completed the study according to the protocol. No adverse events such as nausea, vomiting, or allergies were reported in either group during the trial. The ibuprofen group exhibited significantly lower pain scores at 4 h [2.0 (1.0, 4.0) vs. 4.0 (3.0, 5.0)] (Z=-3.73, P<0.001), 6 h [2.0 (1.0, 4.0) vs. 5.0(2.5, 6.0)] (Z=-3.38, P<0.001), and 8 h [2.0 (1.0, 4.0) vs. 5.0 (2.0, 6.0)] (Z=-2.11, P=0.035) postoperatively compared to the control group. There were no statistically significant differences in pain scores between the groups at 30 min, 24 h, 48 h, and 72 h postoperatively (P>0.05). Additionally, 11 out of 41 patients (26.8%) in the ibuprofen group and 23 out of 41 patients (56.1%) in the control group required extra analgesic medication between days 4 and 6 post-surgery, with the ibuprofen group taking significantly fewer additional pills [0.0 (0.0, 1.0) vs. 1.0 (0.0, 3.0)] (Z=-2.81, P=0.005). Conclusions: A pain management regimen involving 300 mg of oral sustained-release ibuprofen capsules administered 15 minutes before surgery and continued for 3 d postoperatively effectively reduces pain levels and the total amount of analgesic medication used after the extraction of impacted mandibular third molars. Considering its efficacy, safety, and cost-effectiveness, ibuprofen is recommended as a first-line drug for perioperative pain management, enhancing patient comfort during diagnosis and treatment in a feasible manner.


Assuntos
Analgesia , Ibuprofeno , Humanos , Ibuprofeno/uso terapêutico , Ibuprofeno/efeitos adversos , Dente Serotino/cirurgia , Preparações de Ação Retardada/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Analgésicos/uso terapêutico , Método Duplo-Cego , Extração Dentária/efeitos adversos
2.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(5): 1007-1011, 2021 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-34650310

RESUMO

To investigate the surgical effect of hip arthroscopic labrum reconstruction. A retrospective study was performed on the clinical data of 12 patients who underwent hip arthroscopic labrum reconstruction in our department from September 2017 to February 2021 and were followed up for 5-46 months, with an average of 21.5 months. All the patients had a hip joint space of more than 2 mm, and Tonnis grade less than level Ⅱ. These 12 patients underwent arthroscopic debridement of hyperplastic synovium, femoral head and neck and/or acetabular osteoplasty, and labrum reconstruction using autograft iliotibial band or gracilis tendon. After the surgery, we conducted follow-up and data collection, recorded the satisfaction of the patients and occurrence of complications, as well as the cartilage lesion of hip joint observed under the arthroscopy. We compared the alpha angle of Dunn X-ray film, center-edge angle (CE angle) of AP X-ray film, modified Harris hip score (mHHS score), hip outcome score (HOS), international hip outcome tool 12 score (iHOT12 Score), and visual analogue scale (VAS scale) before and after the arthroscopic operation, to assess clinical symptom relief and joint function recovery. The 12 patients were followed up for 5-46 (21.5±12.8) months. The VAS scale were (5.3±2.5) and (2.5±1.4) before and after the surgery, showing significant decrease (P=0.018). The mHHS score were (60.6±22.2) and (83.1±5.8) before and after the surgery, showing significant increase (P=0.003). The patient satisfaction was high (7.8±2.0) (range: 0-10). None of the 12 patients had serious complications, revision surgery, or total hip replacement at the end of the last follow-up. Autologous tendon transplantation for reconstruction of acetabular labrum under arthroscopy can improve the clinical symptoms and joint function of patients with femoroacetabular impingement (FAI), which is a safe and effective treatment.


Assuntos
Impacto Femoroacetabular , Acetábulo/cirurgia , Artroscopia , Impacto Femoroacetabular/cirurgia , Seguimentos , Articulação do Quadril/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento
3.
Lymphology ; 52(2): 71-81, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31525828

RESUMO

We sought to investigate the effects of mesenteric lymph-derived γδ T cells trafficking into intestinal mucosa on gut injury after intestinal ischemia-reperfusion (IIR). γδ T cells were separated from mesenteric lymph and then infused into the femoral vein of rats after the γδ T cells were labeled with 51Cr. Migration of γδ T cells in vivo across the intestinal mucosa was determined by γ-counter. Meanwhile, TNF-α activity and endotoxin concentration in mesenteric lymph were detected. The population of γδ T cells of Peyer's patches in the small intestines was analyzed by immunofluorescence double staining methods and flow cytometry. After IIR injury, the mean optical density value (MOD) and population of γδ T cells in Peyer's patches of the gut and migration of 51Cr-γδ T cells across the intestinal mucosa were significantly increased, which had highly positive correlations to degree of intestinal injury, TNF-α levels and endotoxin concentration in mesenteric lymph after reperfusion. The increased population of γδ T cells derived from mesenteric lymph trafficking into the intestinal mucosa might promote the small intestinal injury after IIR.


Assuntos
Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Linfa , Mesentério , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Subpopulações de Linfócitos T/metabolismo , Animais , Biomarcadores , Biópsia , Movimento Celular , Modelos Animais de Doenças , Suscetibilidade a Doenças , Endotoxinas/efeitos adversos , Imuno-Histoquímica , Imunofenotipagem , Contagem de Linfócitos , Masculino , Nódulos Linfáticos Agregados , Ratos , Traumatismo por Reperfusão/patologia
4.
Phys Rev Lett ; 121(8): 086801, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30192565

RESUMO

Novel mechanisms for electromagnetic wave emission in the terahertz frequency regime emerging at the nanometer scale have recently attracted intense attention for the purpose of searching next-generation broadband THz emitters. Here, we report broadband THz emission, utilizing the interface inverse Rashba-Edelstein effect. By engineering the symmetry of the Ag/Bi Rashba interface, we demonstrate a controllable THz radiation (∼0.1-5 THz) waveform emitted from metallic Fe/Ag/Bi heterostructures following photoexcitation. We further reveal that this type of THz radiation can be selectively superimposed on the emission discovered recently due to the inverse spin Hall effect, yielding a unique film thickness dependent emission pattern. Our results thus offer new opportunities for versatile broadband THz radiation using the interface quantum effects.

5.
J Phys Condens Matter ; 30(30): 305802, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29893723

RESUMO

Ultrathin films of ß-tungsten provide very promising substrates for applications in spintronics, and the possibility of incorporating them into multilayers extends such expectations. Our calculations indicate that it is viable to deposit a single layer of Mn on two non-equivalent (0 0 1) surfaces of ß-tungsten that have easy axes along orthogonal directions [0 1 0] and [1 0 0], respectively. The ferromagnetic structure of this Mn monolayer adsorbed to either of those surfaces displays a giant in-plane magneto-crystalline anisotropy that exceeds 12 meV per Mn atom. Furthermore, when coated with additional layers of ß-tungsten the magnetization easy axis becomes perpendicular to the planes. We envisage that magnetic multilayers involving mono-crystalline thin films of ß-tungsten oriented along high-symmetry directions offer a very fruitful playground for spintronic applications.

6.
Nat Mater ; 17(3): 226-230, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29335610

RESUMO

As a generic property, all substances transfer heat through microscopic collisions of constituent particles 1 . A solid conducts heat through both transverse and longitudinal acoustic phonons, but a liquid employs only longitudinal vibrations2,3. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here, we report liquid-like thermal conduction observed in the crystalline AgCrSe2. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive, and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. These microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.

7.
Fa Yi Xue Za Zhi ; 33(3): 236-238, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29230985

RESUMO

OBJECTIVES: To promote the further research on body stature estimation and the innovative applications based on the distances between the anatomical landmarks on body torso surface. METHODS: A specification for the collection of distances between the anatomical landmarks on body torso surface was established. The data of 933 cases of adult population in Yangtze River Delta region were collected. Multiple linear regression method was used to statistical analyse and establish the regression equation of stature estimation. RESULTS: A regression equation about 5 variables including gender (x1), cervical vertebrae-coccyx line (x2), sterna-pubis line (x3), distance between acromion and iliospinale anterius (x4) and shoulder breadth (x5), and stature (y) was established, y=105.406+5.414 x1+0.436 x2+0.286 x3+0.225 x4+ 0.193 x5. CONCLUSIONS: The method is suitable for the rapid, simple and accurate estimation of stature for the forensic experts.


Assuntos
Estatura , Vértebras Cervicais/anatomia & histologia , Antropologia Forense/métodos , Tronco/anatomia & histologia , Adulto , Osso e Ossos/anatomia & histologia , Feminino , Humanos , Modelos Lineares , Masculino , Análise de Regressão
8.
Nanoscale ; 9(9): 2974-2980, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28221386

RESUMO

Topological insulators hold great potential for efficient information processing and storage. Using density functional theory calculations, we predict that a honeycomb lead monolayer can be stabilized on an Al2O3 (0001) substrate to become topologically non-trivial with a sizeable band gap (∼0.27 eV). Furthermore, we propose to use a hexagonal boron-nitride (h-BN) monolayer as a protection for the topological states of Pb/Al2O3 and Sn/Al2O3. Our findings suggest new possibilities for designing and protecting two-dimensional TIs for practical applications.

9.
J Chem Phys ; 144(20): 204704, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27250322

RESUMO

Structural and magnetic properties of many transition-metal dimers embedded in a defected hexagonal boron nitride monolayer are investigated through density functional calculations to search for systems with magnetic anisotropy energies (MAEs) larger than 30meV. In particular, Ir-Ir@Dh-BN is found to have both large MAE (∼126 meV) and high structural stability against dissociation and diffusion, and it hence can serve as magnetic unit in spintronics and quantum computing devices. This giant MAE mainly results from the spin orbit coupling and the magnetization of the upper Ir atom, which is in a rather isolated environment.

10.
Phys Rev Lett ; 115(24): 249901, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26705662

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.115.077002.

11.
Phys Rev Lett ; 115(7): 077002, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26317742

RESUMO

A major obstacle to using superconducting quantum interference devices (SQUIDs) as qubits is flux noise. We propose that the heretofore mysterious spins producing flux noise could be O_{2} molecules adsorbed on the surface. Using density functional theory calculations, we find that an O_{2} molecule adsorbed on an α-alumina surface has a magnetic moment of ~1.8 µ_{B}. The spin is oriented perpendicular to the axis of the O-O bond, the barrier to spin rotations is about 10 mK. Monte Carlo simulations of ferromagnetically coupled, anisotropic XY spins on a square lattice find 1/f magnetization noise, consistent with flux noise in Al SQUIDs.

12.
Sci Rep ; 3: 3521, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24343479

RESUMO

Magnetostriction of ferromagnetic materials describes the change of their shape or dimension in response to the reorientation of magnetization under the influence of external magnetic field. Fe(100-x)Ga(x) binary alloys (Galfenol) have large magnetostriction and excellent ductility; and they are very promising rare-earth free materials for applications in sensors, actuators, energy-harvesters and spintronic devices. Here we report results of large-scale ab initio molecular dynamics (AIMD) simulations for Galfenol, especially regarding the mechanism that leads to the sudden drop of tetragonal magnetostriction at x ~ 19, a long-standing puzzle for the community. Based on rigid band analysis, we propose possible ways to further optimize the performance of Galfenol for device applications. For example, we found that the substitution of a small amount of Cu for Ga (1.6%) in certain configuration may double the magnetostriction of Galfenol.

13.
Phys Rev Lett ; 110(15): 156101, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25167285

RESUMO

It has been widely assumed that Se terminates the surface of the topological insulator, bismuth selenide. Although some Se is initially at the surface after cleaving at 80 K, low energy ion scattering reveals a complete Bi termination at room temperature. Density functional theory shows that a Bi bilayer atop the bulk-terminated structure is energetically favorable. It is thus proposed that a thermally activated process induces a spontaneous termination change after cleaving. This has profound implications on the electrical transport and long-term stability of such materials and devices.

14.
Phys Rev Lett ; 106(23): 236103, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21770524

RESUMO

To understand the tribological properties of Ne and Kr on Pb(111), the potential energy surfaces for sliding motion of Ne, Kr, and Xe monolayers on the Pb(111) surface are examined through density functional calculations, using either local density or self-consistent nonlocal van der Waals functionals. The calculated adsorption energy for Xe/Pb(111) agrees well with experiment, validating the present approach and parameters. Activation energies along a sliding path indicate that Ne motion is much faster than Kr and Xe on Pb(111) at T∼6 K, which explains the puzzling experimental observation.

15.
Science ; 333(6040): 324-8, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21764744

RESUMO

Kondo lattice systems can exhibit unusual many-body behaviors that result from the interplay between onsite Kondo screening and intersite coupling. We used scanning tunneling microscopy to image the Kondo resonance in a nonconventional Kondo lattice formed by self-assembled oxygen (O(2)) molecules, which are paramagnetic, on the gold reconstructed surface [Au(110)-1×2]. The interplay between the intermolecular coupling for molecules adsorbed along chains and the onsite Kondo effect leads to the coexistence of both local and nonlocal Kondo screening at the atomic level. The latter provides evidence for collective deconfinement of magnetization induced in Au, whereas the former shows local "hybridization" between the Kondo clouds of nearest-neighbor O(2) molecules.

16.
J Phys Condens Matter ; 23(22): 225502, 2011 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-21576768

RESUMO

Substrate-induced spin-orbit splitting in graphene on Ni, Au and Ag(111) is examined on the basis of density-functional theory. The Rashba splitting of π bands along the ΓM direction of the graphene surface Brillouin zone in graphene on Ni(111) is found to be very small (a few millielectronvolts), consistent with the experimental report of Rader et al. Instead, very strong Rashba splitting (near 100 meV) can be obtained for graphene with a certain stretch distortion on a Au substrate. It can be ascribed to the effective match in energy between the C 2p and Au 5d bands, obtained from the analysis of densities of states. The net charge transfer between the graphene and the substrates just affects the spin-orbit effect indirectly. The small spin-orbit splitting induced by the Ag substrates indicates that heavy metals do not always produce large SO splitting. Our findings provide important insights that are useful for understanding the metal-induced Rashba effect in graphene.

17.
J Dent Res ; 90(5): 561-72, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20940368

RESUMO

Cancer is now viewed as a systems biology disease, and oral squamous cell carcinoma (OSCC) can be viewed in a similar fashion. In this paper, we highlight some of the novel molecular events in OSCC, revealed through an integrative strategy of systems biology based on high-throughput omics analysis such as genomics and/or proteomics, the most powerful hypothesis-generating means available today. These approaches have resulted not only in the identification of novel genes for OSCC, but also in more comprehensive networks that describe the mechanisms by which those identified events work, with the promise of developing this knowledge into biomarkers for diagnosis, prognosis, and prediction of therapeutic responses in OSCC patients. Long-term, population-based prospective studies of OSCC patients, and those at high risk of developing OSCC, will then be needed to validate these biomarkers.


Assuntos
Biomarcadores Tumorais , Carcinoma de Células Escamosas/etiologia , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Neoplasias Bucais/etiologia , Biologia de Sistemas/métodos , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Comunicação Celular/fisiologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Papillomavirus Humano 16/patogenicidade , Humanos , Tolerância Imunológica/fisiologia , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Invasividade Neoplásica/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Saliva/química
18.
J Phys Condens Matter ; 22(4): 046001, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-21386325

RESUMO

We address the room-temperature (RT) carbon ferromagnetism by considering the magnetic states of low-dimensional carbons linked by sp-hybridized carbon atoms. Based on the spin-polarized density functional theory calculations, we find that the sp(*) orbitals of carbon atoms can bring magnetic moments into different carbon allotropes which may eventually give rise to the long-range ferromagnetic ordering at room temperature through an indirect carrier-mediated coupling mechanism. The fact that this indirect coupling is Fermi-level-dependent predicts that the individual magnetism of diverse carbon materials is governed by their chemical environments. This mechanism may help to illuminate the RT magnetic properties of carbon-based materials and to explore the new magnetic applications of carbon materials.

19.
J Phys Condens Matter ; 22(17): 175501, 2010 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-21393668

RESUMO

First-principles calculations based on density functional theory were performed to study the stable geometries, electronic structure and magnetic properties of the adsorption of a single Mn atom on a graphitic ZnO sheet and a (9, 0) single-wall ZnO nanotube. For the graphitic ZnO sheet, the Mn atom prefers to reside above the center of a hexagon (H site), with a relatively large binding energy of 1.24 eV. The H site is also the most stable site for adsorption of an Mn atom inside the ZnO nanotube, with a large binding energy of 1.47 eV. In both of these cases, the total magnetic moment is 5.0 µ(B) per Mn atom, which is the same as that of a free Mn atom. When the Mn atom is adsorbed outside the tube, the most energetically favorable site is the atop oxygen site. The magnetic moment is 3.19 µ(B) for this configuration. The smaller magnetic moment is mainly due to the strong p-d mixing of O and Mn orbitals. The different adsorption behaviors are related to the curvatures of the nanostructures.

20.
Phys Rev Lett ; 99(12): 127201, 2007 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17930547

RESUMO

We report ferromagnetism in carbon-doped ZnO. Our first-principles calculations based on density functional theory predicted a magnetic moment of 2.02 mu(B) per carbon when carbon substitutes oxygen in ZnO, and an ferromagnetic coupling among magnetic moments of the carbon dopants. The theoretical prediction was confirmed experimentally. C-doped ZnO films deposited by pulsed-laser deposition showed ferromagnetism with Curie temperatures higher than 400 K. The measured magnetic moment based on the content of carbide in the films [(1.5-3.0) mu(B) per carbon] was in agreement with the theoretical prediction. The magnetism is due to the Zn-C system in the ZnO environment.

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