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1.
Phys Rev Lett ; 123(4): 047203, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31491273

RESUMO

The recent discovery of intrinsic ferromagnetic order in the atomically thin van der Waals crystal CrXTe_{3} (X=Si, Ge) stimulates intensive studies on the nature of low-dimensional magnetism because the presence of long-range magnetic order in two-dimensional systems with continuous symmetry is strictly prohibited by thermal fluctuations. By combining advanced many-body calculations with angle-resolved photoemission spectroscopy we investigate CrSiTe_{3} single crystals and unveil the pivotal role played by the strong electronic correlations at both high- and low-temperature regimes. Above the Curie temperature (T_{c}), Coulomb repulsion (U) drives the system into a charge transfer insulating phase. In contrast, below T_{c} the crystal field arranges the Cr-3d orbitals such that the ferromagnetic superexchange profits, giving rise to the bulk ferromagnetic ground state with which the electronic correlations compete. The excellent agreement between theory and experiment establishes CrSiTe_{3} as a prototype low-dimensional crystal with the cooperation and interplay of electronic correlation and ferromagnetism.

2.
Medicine (Baltimore) ; 97(41): e12752, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30313081

RESUMO

The study aims to evaluate the clinical efficacy of bilateral costotransverse debridement, transpedicular fixation, fusion, and local continuous chemotherapy in 20 patients of contiguous multisegmental thoracic spinal tuberculosis (CMTSTB). We analyzed 20 patients with contiguous thoracic spinal tuberculosis (TB) who underwent surgery via bilateral costotransverse debridement, fusion, posterior instrumentation, and postural drainage with local continuous chemotherapy. The clinical outcomes were evaluated in terms of kyphotic angle, bone fusion, neurologic status, erythrocyte sedimentation rate (ESR), and intraoperative and postoperative complications. All of the patients (8M/12F), averaged 45.8 ±â€Š15.6 years old. The mean duration of postoperative follow-up was 30.7 ±â€Š4.0 months. There was no recurrent TB infection. The values of ESR returned to normal levels at final follow-up. All patients got bony fusion within 8.1 ±â€Š2.3 months after surgery. The average preoperative Cobb angle was 39.9°â€Š±â€Š8.6°, correcting to 9.8°â€Š±â€Š2.3° postoperatively and 10.8°â€Š±â€Š2.3° at the last follow-up. All patients with neurological deficit had dramatic improvement at the final follow-up. Our results showed that bilateral costotransverse surgery and local continuous chemotherapy are feasible and effective procedures in the treatment of CMTSTB. The approach can provide radical debridement, rebuild spinal stability, and cure TB.


Assuntos
Antituberculosos/administração & dosagem , Desbridamento/métodos , Drenagem Postural/métodos , Fusão Vertebral/métodos , Tuberculose da Coluna Vertebral/terapia , Adulto , Idoso , Sedimentação Sanguínea , Terapia Combinada , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vértebras Torácicas/cirurgia , Resultado do Tratamento , Adulto Jovem
3.
Sci Adv ; 4(9): eaat8355, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30225369

RESUMO

Semiconductors are essential materials that affect our everyday life in the modern world. Two-dimensional semiconductors with high mobility and moderate bandgap are particularly attractive today because of their potential application in fast, low-power, and ultrasmall/thin electronic devices. We investigate the electronic structures of a new layered air-stable oxide semiconductor, Bi2O2Se, with ultrahigh mobility (~2.8 × 105 cm2/V⋅s at 2.0 K) and moderate bandgap (~0.8 eV). Combining angle-resolved photoemission spectroscopy and scanning tunneling microscopy, we mapped out the complete band structures of Bi2O2Se with key parameters (for example, effective mass, Fermi velocity, and bandgap). The unusual spatial uniformity of the bandgap without undesired in-gap states on the sample surface with up to ~50% defects makes Bi2O2Se an ideal semiconductor for future electronic applications. In addition, the structural compatibility between Bi2O2Se and interesting perovskite oxides (for example, cuprate high-transition temperature superconductors and commonly used substrate material SrTiO3) further makes heterostructures between Bi2O2Se and these oxides possible platforms for realizing novel physical phenomena, such as topological superconductivity, Josephson junction field-effect transistor, new superconducting optoelectronics, and novel lasers.

4.
Comput Stat Data Anal ; 110: 134-144, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28603325

RESUMO

Marginal screening has been established as a fast and effective method for high dimensional variable selection method. There are some drawbacks associated with marginal screening, since the marginal model can be viewed as a model misspecification from the joint true model. A principal components adjusted variable screening method is proposed, which uses top principal components as surrogate covariates to account for the variability of the omitted predictors in generalized linear models. The proposed method is demonstrated with superior numerical performance compared with the competing methods. The efficiency of the method is also illustrated with the analysis of the Affymetrix genechip rat genome 230 2.0 array data and the European American SNPs data.

5.
Neurochem Int ; 108: 372-380, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28532680

RESUMO

Diabetic neuropathic pain (DNP) plays a major role in decreased life quality of diabetes patients, however, the neural mechanisms underlying DNP remain unclear. Endomorphins are the endogenous ligands for mu-opioid receptor. There is increasing evidence implicating the involvement of spinal endomorphin-2 (EM2) in neuropathic pain. In this study, using a streptozotocin induced diabetic rat model that displayed obvious mechanical allodynia, it was found that the expression of spinal EM2 was significantly decreased in DNP rats. While intrathecal administration of exogenous EM2 attenuated mechanical allodynia in DNP rats, the mu-opioid receptor antagonist ß-funaltrexamine facilitated these events. It was found that the reduction in spinal EM2 was mediated by increased activity of dipeptidylpeptidase IV, possibly as a consequence of diabetes-induced oxidative stress. Taken together, our results provide the first evidence that the reduction in the level of an endogenous opioid in primary afferents was significantly associated with DNP. This indicates that the chronic pain associated with DNP might be due to the loss of an inhibitory effect on pain signal transmission.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Hiperalgesia/metabolismo , Oligopeptídeos/metabolismo , Receptores Opioides mu/metabolismo , Medula Espinal/metabolismo , Animais , Diabetes Mellitus Experimental/patologia , Neuropatias Diabéticas/patologia , Hiperalgesia/patologia , Masculino , Medição da Dor/métodos , Ratos , Ratos Sprague-Dawley , Medula Espinal/patologia , Estreptozocina
6.
Adv Mater ; 29(27)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28481053

RESUMO

Graphene has demonstrated great potential in new-generation electronic applications due to its unique electronic properties such as large carrier Fermi velocity, ultrahigh carrier mobility, and high material stability. Interestingly, the electronic structures can be further engineered in multilayer graphene by the introduction of a twist angle between different layers to create van Hove singularities (vHSs) at adjustable binding energy. In this work, using angle-resolved photoemission spectroscopy with sub-micrometer spatial resolution, the band structures and their evolution are systematically studied with twist angle in bilayer and trilayer graphene sheets. A doping effect is directly observed in graphene multilayer system as well as vHSs in bilayer graphene over a wide range of twist angles (from 5° to 31°) with wide tunable energy range over 2 eV. In addition, the formation of multiple vHSs (at different binding energies) is also observed in trilayer graphene. The large tuning range of vHS binding energy in twisted multilayer graphene provides a promising material base for optoelectrical applications with broadband wavelength selectivity from the infrared to the ultraviolet regime, as demonstrated by an example application of wavelength selective photodetector.

7.
Nat Commun ; 8: 14468, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28186084

RESUMO

The observation of replica bands in single-unit-cell FeSe on SrTiO3 (STO)(001) by angle-resolved photoemission spectroscopy (ARPES) has led to the conjecture that the coupling between FeSe electrons and the STO phonons are responsible for the enhancement of Tc over other FeSe-based superconductors. However the recent observation of a similar superconducting gap in single-unit-cell FeSe/STO(110) raised the question of whether a similar mechanism applies. Here we report the ARPES study of the electronic structure of FeSe/STO(110). Similar to the results in FeSe/STO(001), clear replica bands are observed. We also present a comparative study of STO(001) and STO(110) bare surfaces, and observe similar replica bands separated by approximately the same energy, indicating this coupling is a generic feature of the STO surfaces and interfaces. Our findings suggest that the large superconducting gaps observed in FeSe films grown on different STO surface terminations are likely enhanced by a common mechanism.

8.
Cell Physiol Biochem ; 39(5): 1930-1940, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27771708

RESUMO

BACKGROUND/AIMS: The purpose of this study was to investigate the implications of protein kinase C-epsilon (PKCε), Extracellular Signal-regulated Kinase 1/2 (ERK1/2) and mitochondrial permeability transition pore (mPTP) in myocardial protection induced by morphine postconditioning (MpostC). METHODS: The isolated rat hearts were randomly assigned into one of eight groups. Hearts in time control (TC) group were constantly perfused for 105min. Hearts in ischemia-reperfusion (I/R) group were subjected to 45 min of ischemia followed by 1 h of reperfusion. MpostC was induced by 10 min of morphine administration at the onset of reperfusion. εV1-2 (an inhibitor of PKCε) and PD (an inhibitor of ERK1/2) was administered with or without morphine during the first 10 min of reperfusion following the 45 min of ischemia. I/R injury was assessed by functional parameters, creatine kinase-MB (CK-MB) release and infarct size (IS/AAR). Additional hearts were excised at 20 min following reperfusion to detect the membrane-specific translocation of PKCε, ERK1/2 phosphorylation, mitochondrial permeability transition (MPT) and cytochrome C (Cyt-c) release. RESULTS: MpostC markedly reduced infarct size (IS/AAR), CK-MB release, and improved cardiac function recovery. However, these protective effects were partly abolished in the presence of εV1-2 or PD. Compared to TC group, the membrane translocation of PKCε, ERK1/2 phosphorylation, mPTP opening, and Cyt-c release were significantly increased in I/R hearts. MpostC further increased the membrane translocation of PKCε and ERK1/2 phosphorylation, and significantly inhibited mPTP opening and Cyt-c release. However, those protective effects induced by MpostC were abolished by εV1-2 or PD, which, used alone, showed no influence on reperfusion injury. CONCLUSIONS: These findings suggest that MpostC protects isolated rat hearts against ischemia-reperfusion injury via activating PKCε-ERK1/2 pathway and inhibiting mPTP opening.


Assuntos
Proteínas de Transporte da Membrana Mitocondrial/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Morfina/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Proteína Quinase C-épsilon/genética , Animais , Creatina Quinase Forma MB/metabolismo , Citocromos c/metabolismo , Regulação da Expressão Gênica , Pós-Condicionamento Isquêmico/métodos , Masculino , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Morfina/antagonistas & inibidores , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Técnicas de Cultura de Órgãos , Fragmentos de Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Quinase C-épsilon/metabolismo , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
9.
J Zhejiang Univ Sci B ; 17(7): 568, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27381734

RESUMO

The original version of this article unfortunately contained a mistake. In "Abstract" and the 1st para-graph of Section 2.1, the full name of the abbreviation "ASA" was incorrect in "American Standards Association (ASA)". The correct version should be "American Society of Anesthesiologists (ASA)".

10.
Nano Lett ; 16(8): 4738-45, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27357620

RESUMO

Layered transition metal chalcogenides with large spin orbit coupling have recently sparked much interest due to their potential applications for electronic, optoelectronic, spintronics, and valleytronics. However, most current understanding of the electronic structure near band valleys in momentum space is based on either theoretical investigations or optical measurements, leaving the detailed band structure elusive. For example, the exact position of the conduction band valley of bulk MoS2 remains controversial. Here, using angle-resolved photoemission spectroscopy with submicron spatial resolution (micro-ARPES), we systematically imaged the conduction/valence band structure evolution across representative chalcogenides MoS2, WS2, and WSe2, as well as the thickness dependent electronic structure from bulk to the monolayer limit. These results establish a solid basis to understand the underlying valley physics of these materials, and also provide a link between chalcogenide electronic band structure and their physical properties for potential valleytronics applications.

11.
Cell Physiol Biochem ; 39(1): 61-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27322569

RESUMO

BACKGROUND: The purpose of this study was to determine whether c-jun NH2 amino-terminal kinases (JNK) and p38 mitogen-activated protein kinases (MAPK) were involved in morphine postconditioning (MpostC). METHODS: The isolated rat hearts were randomly assigned into one of the following groups. Hearts in the time control (TC) group were constantly perfused for 105min. Hearts in the ischemia-reperfusion (I/R) group were subjected to 45 min of ischemia followed by 1 h of reperfusion. MpostC was induced by 10 min of morphine administration at the onset of reperfusion. Anisomycin (an activator of JNK/p38 kinases) was administered with or without morphine during the first 10 min of reperfusion following the 45 min of ischemia. Mitochondria and cytosolic proteins were prepared to detect mitochondrial permeability transition (MPT) and cytochrome C (Cyt-c) respectively. RESULTS: MpostC markedly reduced infarct size (IS/AAR), CK-MB release, and improved cardiac function recovery. However, these protective effects were partly abolished in the presence of anisomycin. I/R significantly increased the phosphorylation of JNK and p38 kinases, mitochondrial permeability transition (MPT) opening and Cyt-c release, while these effects were partly abolished by MpostC. The inhibitory effects of MpostC on the phosphorylation of JNK/p38 kinases, MPT opening and Cyt-c release were totally reversed by Anisocycin, which, used individually, did not show any influence on perfusion injury. CONCLUSIONS: These findings suggest that MpostC protects isolated rat hearts against reperfusion injury via inhibiting JNK/p38 MAPKs and mitochondrial permeability transition pores signaling pathways.


Assuntos
Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Morfina/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Analgésicos Opioides/farmacologia , Animais , Western Blotting , Cardiotônicos/farmacologia , Citocromos c/metabolismo , Coração/efeitos dos fármacos , Coração/fisiopatologia , Técnicas In Vitro , Masculino , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Fosforilação/efeitos dos fármacos , Distribuição Aleatória , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia
12.
Sci Rep ; 6: 26903, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27228908

RESUMO

Recently, the layered semimetal WTe2 has attracted renewed interest owing to the observation of a non-saturating and giant positive magnetoresistance (~10(5)%), which can be useful for magnetic memory and spintronic devices. However, the underlying mechanisms of the giant magnetoresistance are still under hot debate. Herein, we grew the stoichiometric and non-stoichiometric WTe2 crystals to test the robustness of giant magnetoresistance. The stoichiometric WTe2 crystals have magnetoresistance as large as 3100% at 2 K and 9-Tesla magnetic field. However, only 71% and 13% magnetoresistance in the most non-stoichiometry (WTe1.80) and the highest Mo isovalent substitution samples (W0.7Mo0.3Te2) are observed, respectively. Analysis of the magnetic-field dependent magnetoresistance of non-stoichiometric WTe2 crystals substantiates that both the large electron-hole concentration asymmetry and decreased carrier mobility, induced by non-stoichiometry, synergistically lead to the decreased magnetoresistance. This work sheds more light on the origin of giant magnetoresistance observed in WTe2.

13.
Rev Sci Instrum ; 87(1): 011301, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26827301

RESUMO

We developed a table-top vacuum ultraviolet (VUV) laser with 113.778 nm wavelength (10.897 eV) and demonstrated its viability as a photon source for high resolution angle-resolved photoemission spectroscopy (ARPES). This sub-nanosecond pulsed VUV laser operates at a repetition rate of 10 MHz, provides a flux of 2 × 10(12) photons/s, and enables photoemission with energy and momentum resolutions better than 2 meV and 0.012 Å(-1), respectively. Space-charge induced energy shifts and spectral broadenings can be reduced below 2 meV. The setup reaches electron momenta up to 1.2 Å(-1), granting full access to the first Brillouin zone of most materials. Control over the linear polarization, repetition rate, and photon flux of the VUV source facilitates ARPES investigations of a broad range of quantum materials, bridging the application gap between contemporary low energy laser-based ARPES and synchrotron-based ARPES. We describe the principles and operational characteristics of this source and showcase its performance for rare earth metal tritellurides, high temperature cuprate superconductors, and iron-based superconductors.

14.
Eur Spine J ; 25(2): 557-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26071944

RESUMO

AIM: To investigate the efficacy and safety of temporary internal distraction corrective surgery for extremely severe scoliosis. METHODS: Eleven scoliosis patients (3 males and 8 females) with curves ≥130° (mean 148.8°; range 130°-157°) who underwent a two-stage surgery, including a posterior temporary internal distraction correction and definitive posterior spinal correction with posterior pedicle screw instrumentation from 2008 to 2011 were retrospectively reviewed. Minimum follow-up was 2-years (mean 41.8 months; range 27.0-63.0 months). The analysis focused on the impact of temporary internal distraction on curve correction, pulmonary function tests (PFTs), complications and surgical outcomes. Neurosurveillance of sensory (somatosensory-evoked potentials) and motor (motor-evoked potentials) potential was performed in all cases. Posterior instrumentation was used in all patients. RESULTS: After the use of internal distraction, the preoperative major curve (mean 148.8°; range 130°-157°) was corrected to a mean of 79° (range 63°-87°), the T5-T12 kyphosis Cobb angle (mean 79°; range 30°-97°) was corrected to a mean of 59° (range 20°-75°), the coronal imbalance (mean 0.8 cm; range -3.6 to 2.8 cm) was improved to a mean of 0.6 cm (range -1.5 to 2.0 cm), the forced vital capacity percentage (FVC%) was improved from 59.3 ± 11.6 to 68.7 ± 13.7, and the forced expiratory volume in 1 s (FEV1%) was improved from 61.4 ± 13.6 to 71.3 ± 9.3. The average increase in body height was 6.7 cm, and the dorsum razor was corrected to 3-5 cm. During definitive surgery, the final major curves were corrected to a mean of 55° (range 32°-72°), the T5-T12 kyphosis Cobb was corrected to 35° (range 15°-68°), the coronal imbalance was improved to 0.5 cm (range -1.2 to 1.8 cm), the FVC% was improved to 71.2 ± 8.3, the FEV1% was improved to 76.3 ± 16.7, the increase in body height was 3.1 cm, and the dorsum razor was corrected to 1-3 cm. The mean interval time between the two surgeries was 3.5 months. None of the patients exhibited postoperative neurologic deficits or infections. No instrument complications were found during the final follow-up. CONCLUSIONS: Temporary internal distraction in a two-stage corrective surgery provided patients who had extremely severe and rigid scoliosis, an effective and safe solution for scoliosis without significant complications.


Assuntos
Cifose/cirurgia , Parafusos Pediculares , Escoliose/cirurgia , Fusão Vertebral/métodos , Adolescente , Estatura , Potencial Evocado Motor , Potenciais Somatossensoriais Evocados , Feminino , Humanos , Cifose/fisiopatologia , Masculino , Complicações Pós-Operatórias , Período Pós-Operatório , Testes de Função Respiratória , Estudos Retrospectivos , Escoliose/fisiopatologia , Índice de Gravidade de Doença , Resultado do Tratamento , Capacidade Vital , Adulto Jovem
15.
J Zhejiang Univ Sci B ; 16(12): 1042-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26642187

RESUMO

OBJECTIVE: To explore the relationship of postoperative cognitive dysfunction (POCD) in one-lung ventilation (OLV) patients and regional cerebral oxygen saturation (rSO2). METHODS: Twenty-nine male and twenty-one female cases of OLV received thoracic surgery, with American Standards Association (ASA) physical status being at Grades I-III. Neuropsychological tests were performed on the day before operation and 7 d after operation, and there was an intraoperative continuous monitoring of rSO2. The values of rSO2 before anesthesia induction (t1), at the beginning of OLV (t2), and at the time of OLV 30 min (t3), OLV 60 min (t4), the end of OLV (t5), and the end of surgery (t6) were recorded. The intraoperative average of rSO2 , the intraoperative minimum value of rSO2 (rSO(2, min)), and the reduced maximum percentage of rSO2 (rSO(2, %max)) when compared with the baseline value were calculated. The volume of blood loss, urine output, and the amount of fluid infusion was recorded. RESULTS: A total of 14 patients (28%) in the 50 cases suffered from POCD. The values of mini-mental state examination (MMSE), the digit span and the digit symbol on the 7th day after the operation for POCD in OLV patients were found to be significantly lower than those before the operation (P<0.05). The values of MMSE and vocabulary fluency scores were significantly lower than those in the non-POCD group (P<0.05). The values of rSO2 in the POCD group of OLV patients at t2 and t3 and the values of rSO2 in the non-POCD group at t2 were found to be significantly higher than those at t1 (P<0.05). The values of rSO(2, %max) in the POCD group were significantly higher than those in the non-POCD group (P<0.05). When the value of rSO(2, %max) is more than 10.1%, it may act as an early warning index for cognitive function changes. CONCLUSIONS: POCD after OLV may be associated with a decline in rSO2.


Assuntos
Encéfalo/metabolismo , Transtornos Cognitivos/etiologia , Ventilação Monopulmonar/efeitos adversos , Oxigênio/sangue , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Encéfalo/irrigação sanguínea , Estudos de Casos e Controles , Cognição , Transtornos Cognitivos/sangue , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Valor Preditivo dos Testes , Fatores de Risco , Fatores de Tempo
16.
Int J Clin Exp Med ; 8(8): 14115-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550379

RESUMO

OBJECTIVE: To discuss the effect of preemptive analgesia with parecoxib sodium in patients undergoing radical resection of lung cancer. METHODS: 115 cases of lung cancer patients with American society of anesthesiologists class (ASA) grade I~II who received selective operation were randomly divided into the research group and the control group. The research group patients were given preoperative parecoxib sodium 40 mg plus postoperative normal saline 2 ml, while the control group patients were treated with preoperative normal saline 2 ml plus postoperative parecoxib sodium 40 mg. The pain condition at postoperative 1, 2, 4, 8, 12, 24 and 48 h were evaluated by visual analogue scale (VAS), and emergence agitation was tested by agitation score. RESULTS: Finally there were 56 cases and 57 cases can be used for evaluation in the research group and control group. The VAS scores after 1, 2, 4, 8, 12, 24 and 48 h in the research group and control group were [2.23±0.45, 2.35±0.48, 2.51±0.51, 2.41±0.45, 2.28±0.42, 2.16±0.39, 2.11±0.40] and [3.80±0.62, 4.01±0.64, 4.31±0.67, 4.10±0.64, 3.65±0.70, 3.12±0.66, 2.46±0.53], respectively. The research group were obviously lower than the control group, the difference were statistically significant (P<0.05). The rate of agitation was 24.44% (11/56) in the research group, significantly lower than the control group of 59.65% (34/57) (P<0.05). CONCLUSION: Preemptive analgesia with parecoxib sodium can obviously relieve acute pain using in patients undergoing radical resection of lung cancer, and is helpful to reduce the incidence of emergence agitation.

17.
Arch Orthop Trauma Surg ; 135(4): 491-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25720848

RESUMO

OBJECTIVE: Our objective was to evaluate the efficacy and safety of Batroxobin on blood loss during spinal operations. METHODS: After obtaining approval from the ethics committee at the hospital along with informed written consent, we performed a double-blind, randomized, placebo-controlled study with 100 patients who were randomized equally into 2 groups (Batroxobin and placebo). Patients received either 2 ku IV 15 min before surgery and followed 1 ku IM of Batroxobin following surgery, or an equivalent volume of placebo (normal saline). Cost of Batroxobin treatment is amounted to 84.75 euros. The primary outcomes were intraoperative, 24 h postoperative, and total perioperative blood loss. Secondary outcomes were hemoglobin (Hb), red blood cell count (RBC), the volume of blood/fluid transfusion intraoperatively, and 24 h postoperatively. Safety evaluation parameters were the incidence of venous thrombosis in the lower extremities, active partial thromboplastin time, prothrombin time, thrombin time, and fibrinogen. The data were analyzed using the Statistical Package for the Social Science Version 12.0. The results were presented as mean ± SEM. The Mann-Whitney test and Independent Student t test, when appropriate, were used to compare the 2 groups, and differences were considered significant if the P value was <0.05. RESULTS: 88 patients were included in the analysis while 12 patients were withdrawn from the study due to extended surgical duration, change of surgical procedure, or after the patients' request. The total perioperative blood loss was approximately 31% lower in patients given Batroxobin versus placebo (700.5 ± 45.81 vs 485.7 ± 30.01 mL, P = 0.001). The Batroxobin group had significantly less intraoperative blood loss (326.1 ± 24.16) compared to the placebo group (556.0 ± 43.58), but there was no difference in the amount of blood/fluid transfused, postoperatively Hb, or RBC between the two groups. After the operation, coagulation parameters were not significantly different between the 2 groups at the days 1 or 3 postoperatively. No adverse events related to the use of Batroxobin were recorded. There were no cases of superficial wound infection. None of the subjects died during the study. CONCLUSIONS: In this study, prophylactic use of Batroxobin provided an effective and cheap method for reducing blood loss without coagulopathy during or after operations. The use of Batroxobin for patients undergoing one-level PLIF surgery safely and effectively reduced the total amount of perioperative blood loss.


Assuntos
Batroxobina/administração & dosagem , Perda Sanguínea Cirúrgica/prevenção & controle , Fusão Vertebral , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Hemostáticos/administração & dosagem , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Adulto Jovem
18.
Nat Nanotechnol ; 9(2): 111-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24362235

RESUMO

Quantum systems in confined geometries are host to novel physical phenomena. Examples include quantum Hall systems in semiconductors and Dirac electrons in graphene. Interest in such systems has also been intensified by the recent discovery of a large enhancement in photoluminescence quantum efficiency and a potential route to valleytronics in atomically thin layers of transition metal dichalcogenides, MX2 (M = Mo, W; X = S, Se, Te), which are closely related to the indirect-to-direct bandgap transition in monolayers. Here, we report the first direct observation of the transition from indirect to direct bandgap in monolayer samples by using angle-resolved photoemission spectroscopy on high-quality thin films of MoSe2 with variable thickness, grown by molecular beam epitaxy. The band structure measured experimentally indicates a stronger tendency of monolayer MoSe2 towards a direct bandgap, as well as a larger gap size, than theoretically predicted. Moreover, our finding of a significant spin-splitting of ∼ 180 meV at the valence band maximum of a monolayer MoSe2 film could expand its possible application to spintronic devices.

19.
Nat Nanotechnol ; 6(11): 705-9, 2011 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-21963714

RESUMO

Topological insulators exhibit a bulk energy gap and spin-polarized surface states that lead to unique electronic properties, with potential applications in spintronics and quantum information processing. However, transport measurements have typically been dominated by residual bulk charge carriers originating from crystal defects or environmental doping, and these mask the contribution of surface carriers to charge transport in these materials. Controlling bulk carriers in current topological insulator materials, such as the binary sesquichalcogenides Bi2Te3, Sb2Te3 and Bi2Se3, has been explored extensively by means of material doping and electrical gating, but limited progress has been made to achieve nanostructures with low bulk conductivity for electronic device applications. Here we demonstrate that the ternary sesquichalcogenide (Bi(x)Sb(1-x))2Te3 is a tunable topological insulator system. By tuning the ratio of bismuth to antimony, we are able to reduce the bulk carrier density by over two orders of magnitude, while maintaining the topological insulator properties. As a result, we observe a clear ambipolar gating effect in (Bi(x)Sb(1-x))2Te3 nanoplate field-effect transistor devices, similar to that observed in graphene field-effect transistor devices. The manipulation of carrier type and density in topological insulator nanostructures demonstrated here paves the way for the implementation of topological insulators in nanoelectronics and spintronics.


Assuntos
Antimônio/química , Bismuto/química , Magnetismo , Membranas Artificiais , Nanoestruturas/química , Nanotecnologia/instrumentação , Telúrio/química , Ligas/química , Cristalização/métodos , Eletrônica , Teste de Materiais , Nanoestruturas/ultraestrutura , Propriedades de Superfície , Temperatura Ambiente , Transistores Eletrônicos
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