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1.
Phys Rev Lett ; 132(18): 186001, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38759199

RESUMEN

The kagome materials AV_{3}Sb_{5} (A=K, Rb, Cs) host an intriguing interplay between unconventional superconductivity and charge-density waves. Here, we investigate CsV_{3}Sb_{5} by combining high-resolution thermal-expansion, heat-capacity, and electrical resistance under strain measurements. We directly unveil that the superconducting and charge-ordered states strongly compete, and that this competition is dramatically influenced by tuning the crystallographic c axis. In addition, we report the absence of additional bulk phase transitions within the charge-ordered state, notably associated with rotational symmetry breaking within the kagome planes. This suggests that any breaking of the C_{6} invariance occurs via different stacking of C_{6}-symmetric kagome patterns. Finally, we find that the charge-density-wave phase exhibits an enhanced A_{1g}-symmetric elastoresistance coefficient, whose large increase at low temperature is driven by electronic degrees of freedom.

2.
Ecotoxicol Environ Saf ; 274: 116199, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38492485

RESUMEN

This study established a residue detection method based on the QuEChERS pre-treatment method and combined it with high-performance liquid chromatography-tandem mass spectrometry to test six herbicides (metamitron, clopyralid, desmedipham, phenmedipham, ethofumesate, and haloxyfop-p-methyl) in sugar beet plants, soil, and roots. The degradation dynamics and terminal residues of each herbicide in sugar beets were analysed. Finally, the dietary risks of various herbicides in sugar beets were evaluated based on the dietary structure of Chinese people, and the risk quotient values were below 100%. Using this detection method, all reagents exhibited good linearity (0.9724 ≤ R2 ≤ 0.9998), The limit of quantification (LOQ) ranged from 0.01 to 0.05 mg/L, the matrix effect ranged from -1.2% to -50%, the addition recovery rate ranged from 77.00% to 103.48%, and the relative standard deviation ranged from 1.61% to 16.17%; therefore, all indicators of this method met the residue detection standards. Under field conditions, the half-lives (t1/2) ranged about 0.65 ∼ 2.96 d and 0.38 ∼ 27.59 d in sugar beet plants and soil, respectively. All herbicides were easily degraded in sugar beet plants and soil (t1/2 < 30 d). The terminal residue amounts in the beet plants, soil, and roots ranged from < LOQ to 0.243 mg/kg. The dietary risk assessment of each pesticide was conducted based on the residual median of the terminal residues and the highest residual values on the edible part of the beetroot. The chronic exposure risk quotient (RQc) and acute exposure risk quotient (RQa) values were < 100%, indicating that the residue of each pesticide in beetroot posed low risks to consumers in China at the recommended dosage.


Asunto(s)
Beta vulgaris , Compuestos de Flúor , Herbicidas , Residuos de Plaguicidas , Plaguicidas , Piridinas , China , Herbicidas/análisis , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Suelo/química , Azúcares , Verduras
3.
Microbiol Spectr ; 12(2): e0336823, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38197657

RESUMEN

Terrestrial plants can influence the growth and health of adjacent plants through interspecific interaction. Here, the mechanisms of interspecific plant interaction on microbial function and nutrient utilization in the plant-soil interface (non-rhizosphere soil, rhizosphere soil, and root) were studied by soybean- and potato-poplar intercropping. First, metagenomics showed that soybean- and potato-poplar intercropping influenced the composition and co-occurrence networks of microbial communities in different ecological niches, with higher stability of the microbial community in soybean intercropping. Second, the gene abundance related to carbon metabolism, nitrogen cycling, phosphorus cycling, and sulfur cycling was increased at the poplar-soil interface in soybean intercropping. Moreover, soybean intercropping increased soil nutrient content and enzymatic activity. It showed higher metabolic potential in nutrient metabolism and transportation. Third, functional microorganisms that influenced nutrient cycling and transportation in different intercropping have been identified, namely Acidobacteria, Sphingomonas, Gemmatimonadaceae, Alphaproteobacteria, and Bradyrhizobium. Therefore, intercropping can construct microbial communities to alter metabolic functions and improve nutrient cycling and absorption. Interspecific plant interactions to influence the microbiome were revealed, opening up a new way for the precise regulation of plant microbiome.IMPORTANCEPoplar has the characteristics of wide distribution, strong adaptability, and fast growth, which is an ideal tree species for timber forest. In this study, metagenomics and elemental analysis were used to comprehensively reveal the effects of interspecific plant interactions on microbial communities and functions in different ecological niches. It can provide a theoretical basis for the development and application of the precise management model in poplar.


Asunto(s)
Microbiota , Suelo , Suelo/química , Agricultura , Glycine max , Bacterias/genética , Microbiología del Suelo
4.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36499002

RESUMEN

Low temperature is an important environmental factor that affects the growth and development of trees and leads to the introduction of failure in the genetic improvement of trees. Acer pseudosieboldianum is a tree species that is well-known for its bright red autumn leaf color. These trees are widely used in landscaping in northeast China. However, due to their poor cold resistance, introduced A. pseudosieboldianum trees suffer severe freezing injury in many introduced environments. To elucidate the physiological indicators and molecular mechanisms associated with freezing damage, we analyzed the physiological indicators and transcriptome of A. pseudosieboldianum, using kits and RNA-Seq technology. The mechanism of A. pseudosieboldianum in response to freezing stress is an important scientific question. In this study, we used the shoots of four-year-old A. pseudosieboldianum twig seedlings, and the physiological index and the transcriptome of A. pseudosieboldianum under low temperature stress were investigated. The results showed that more than 20,000 genes were detected in A. pseudosieboldianum under low temperature (4 °C) and freezing temperatures (-10 °C, -20 °C, -30 °C, and -40 °C). There were 2505, 6021, 5125, and 3191 differential genes (DEGs) between -10 °C, -20°C, -30°C, -40 °C, and CK (4 °C), respectively. Among these differential genes, 48 genes are involved in the MAPK pathway and 533 genes are involved in the glucose metabolism pathway. In addition, the important transcription factors (MYB, AP2/ERF, and WRKY) involved in freezing stress were activated under different degrees of freezing stress. A total of 10 sets of physiological indicators of A. pseudosieboldianum were examined, including the activities of five enzymes and the accumulation of five hormones. All of the physiological indicators except SOD and GSH-Px reached their maximum values at -30 °C. The enzyme activity of SOD was highest at -10 °C, and that of GSH-Px was highest at -20 °C. Our study is the first to provide a more comprehensive understanding of the differential genes (DEGs) involved in A. pseudosieboldianum under freezing stress at different temperatures at the transcriptome level. These results may help to clarify the molecular mechanism of cold tolerance of A. pseudosieboldianum and provide new insights and candidate genes for the genetic improvement of the freezing tolerance of A. pseudosieboldianum.


Asunto(s)
Acer , Regulación de la Expresión Génica de las Plantas , Acer/genética , Perfilación de la Expresión Génica , Transcriptoma , Congelación
5.
BMC Musculoskelet Disord ; 23(1): 982, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36376871

RESUMEN

STUDY DESIGN: Retrospective study. OBJECTIVES: To explore the incidence and risk factors for symptomatic adjacent segment disease (ASD) in patients enveloped in degenerative lumbar diseases after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). METHODS: Data were retrospectively analyzed on 744 patients who underwent MIS-TLIF for degenerative lumbar diseases in our hospital from October 2012 to December 2018. The patients were divided into the ASD group and non-ASD (N-ASD) group on the basis of developing ASD at follow-up, and then the incidence of ASD was calculated. Clinical and radiological risk factors were assessed over time to determine their association with ASD by excluding less important factors. RESULTS: Data were missing for 26 patients, while a total of 718 patients were successfully monitored after MIS-TLIF. Of the 718 individuals participated in the study, 34 (4.7%) patients plagued by ASD required surgical intervention. The average onset time of ASD was 62.7 ± 15.1 months. Univariate analysis results shows that age, bone mineral density (BMD), body mass index (BMI), preoperative adjacent intervertebral disc height and preoperative adjacent segment disc degeneration were significantly different between the ASD and N-ASD groups (p < 0.05). The logistic regression analysis results demonstrated that BMD (p = 0.039, OR = 0.986, 95% CI 0.899-1.115), BMI (p = 0.041, OR = 1.119, 95% CI 1.103-2.397), and preoperative adjacent intervertebral disc degeneration (p = 0.023, OR = 1.215, 95% CI 1.015-1.986) may be seen as risk factors for ASD after MIS-TLIF. CONCLUSIONS: The incidence of ASD was about 4.7% in patients suffer from degenerative lumbar diseases after MIS-TLIF. BMD, BMI and preoperative adjacent intervertebral disc degeneration might be the risk factors for the occurrence of ASD after MIS-TLIF. Our research also suggested that patients with lower BMD, higher BMI and disc preoperative adjacent segment disc degeneration were more likely to develop ASD after MIS-TLIF.


Asunto(s)
Degeneración del Disco Intervertebral , Fusión Vertebral , Humanos , Fusión Vertebral/efectos adversos , Fusión Vertebral/métodos , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/epidemiología , Degeneración del Disco Intervertebral/cirugía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Estudios Retrospectivos , Incidencia , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Resultado del Tratamiento , Factores de Riesgo
6.
J Healthc Eng ; 2022: 4457673, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295173

RESUMEN

Background: The apoptosis of nucleus pulposus (NP) cells reduces the number of nucleus pulposus cells in intervertebral disc tissue, resulting in intervertebral disc degeneration (IDD). MicroRNAs (miRNAs) play an important regulatory role in abnormal cell proliferation and apoptosis. Methods: The miR-27a-3p expressions in degenerative NP tissue and cells were measured via qPCR. The impacts of miR-27a-3p on the proliferation and apoptosis of human NP cells were evaluated by flow cytometry assays, MTT assays, and western blot analyses. In addition, target scan and luciferase reporter assay were applied to confirm that RASSF5 was directly binding to miR-27a-3p. Western blot was applied to assess the relationship between miR-27a-3p, RASSF5 and MST1/LATS1, and RAS/RAC1 signaling pathway. Results: MiR-27a-3p was downregulated in degenerative NP tissues and cells by comparison with the control group. MiR-27a-3p overexpression enhanced cell proliferation and suppressed apoptosis of NP cells, while the above factors showed an opposite tendency after in the miR-27a-3p inhibitor group. The western blot experiment similarly suggested mir-27a-3p apparently downregulated apoptosis-related proteins (Bax and caspase-3) and upregulated antiapoptotic proteins (Bcl-2). In addition, RASSF5 was confirmed to be directly regulated by miR-27a-3p using the luciferase reporter assay. Overexpressed RASSF5 could reverse the effects caused by miR-27a-3p mimic. Finally, miR-27a-3p could downregulate RASSF5 and affected the MST1/LATS1 and RAS/RAC1 pathway. Conclusion: MiR-27a-3p may target RASSF5 and enhance cell proliferation and imped cell apoptosis of the nucleus pulposus cells via the MST1/LATS1 and RAS/RAC1 pathway, lessening the degeneration of intervertebral discs.


Asunto(s)
Degeneración del Disco Intervertebral , MicroARNs , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Degeneración del Disco Intervertebral/genética , Luciferasas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Serina-Treonina Quinasas , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo , Transducción de Señal
7.
Phys Rev Lett ; 126(10): 107001, 2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33784111

RESUMEN

Interactions between nematic fluctuations, magnetic order and superconductivity are central to the physics of iron-based superconductors. Here we report on in-plane transverse acoustic phonons in hole-doped Sr_{1-x}Na_{x}Fe_{2}As_{2} measured via inelastic x-ray scattering, and extract both the nematic susceptibility and the nematic correlation length. By a self-contained method of analysis, for the underdoped (x=0.36) sample, which harbors a magnetically ordered tetragonal phase, we find it hosts a short nematic correlation length ξ∼10 Å and a large nematic susceptibility χ_{nem}. The optimal-doped (x=0.55) sample exhibits weaker phonon softening effects, indicative of both reduced ξ and χ_{nem}. Our results suggest short-range nematic fluctuations may favor superconductivity, placing emphasis on the nematic correlation length for understanding the iron-based superconductors.

8.
World Neurosurg ; 147: e343-e350, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33346054

RESUMEN

OBJECTIVE: To evaluate effectiveness of regular and modified drill templates used to guide cervical anterior transpedicular screw (ATPS) placement. METHODS: This study included 15 adult cadaveric specimens. Computed tomography images were imported into Mimics software. Three-dimensional modeling of all cervical vertebrae was done, and the ideal trajectories were designed for ATPSs. Models of regular and modified templates were designed for every level on the left or right side randomly. After three-dimensional printing, 2 types of templates were used to guide the insertion. Postoperative computed tomography scans were used to measure deviations between real and ideal trajectories in the direction and positioning of entry points. The deviations in the 2 groups were compared using paired t test. RESULTS: There were 120 templates and ATPSs fabricated and placed. Postoperative images showed that 7 screws perforated pedicles in the regular group, with an accuracy rate of 88.3%. Deviations between real and ideal trajectories in cranially inclined angles and extroversive angles were 1.13° ± 0.61° and 0.97° ± 0.60°, respectively, and deviations of entry point position in the x-axis and y-axis were 0.72 ± 0.38 mm and 0.95 ± 0.47 mm, respectively. In the modified group, there were 2 malposition screws with accuracy rate of 96.7%. Deviations in cranially inclined angles were 0.66° ± 0.53° and 0.66° ± 0.55° in extroversive angles, respectively, and deviations in entry point positions in the x-axis and y-axis were 0.45 ± 0.37 mm and 0.51 ± 0.34 mm, respectively. The differences in deviations between groups were statistically significant. CONCLUSIONS: Compared with regular drill templates, modified drill templates can provide higher accuracy and stronger trajectory control in ATPS insertions.


Asunto(s)
Tornillos Óseos , Vértebras Cervicales/cirugía , Fijadores Internos , Cuello/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Cirugía Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos
9.
Phys Rev Lett ; 124(25): 257601, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32639769

RESUMEN

The nature of the hidden-order (HO) state in URu_{2}Si_{2} remains one of the major unsolved issues in heavy-fermion physics. Recently, torque magnetometry, x-ray diffraction, and elastoresistivity data have suggested that the HO phase transition at T_{HO}≈ 17.5 K is driven by electronic nematic effects. Here, we search for thermodynamic signatures of this purported structural instability using anisotropic thermal expansion, Young's modulus, elastoresistivity, and specific-heat measurements. In contrast to the published results, we find no evidence of a rotational symmetry breaking in any of our data. Interestingly, our elastoresistivity measurements, which are in full agreement with published results, exhibit a Curie-Weiss divergence, which we however attribute to a volume and not to a symmetry-breaking effect. Finally, clear evidence for thermal fluctuations is observed in our heat-capacity data, from which we estimate the HO correlation length.

10.
Zhongguo Gu Shang ; 32(6): 524-530, 2019 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-31277535

RESUMEN

OBJECTIVE: The 3D model of lumbar spine was established by using Mimics software. To observe the applicability and needling parameters of lumbar vertebral kyphoplasty with unilateral puncture by backward rotation method using simulated puncture. METHODS: Twenty-four patients (12 males and 12 females) with osteoporotic thoracic fracture in the first time and no signs of lumbar misalignment and bone destruction were scanned by spiral CT on the lumbar spine. The original DICOM file was modeled in 3D with Mimics software, and the vertebral bodies were separated. After being imported into 3-matic software, the posterior wall of the vertebral body was restrained for standardized measurement. A sketch perpendicular to the mid-section of the pedicle and the posterior wall of the vertebral body was drawn. The simulated puncture was performed on the sketch. The angle and distance parameters of the range of motion of the puncture needle were recorded, and the puncture needle was recorded at the top. The crossing points of the anterior, middle and posterior zones of the tangential line of the vertebral body were located at the high extraversion angle, and the results were compared and analyzed. RESULTS: All the data in the left and right sides had no significantly differences(P>0.05). Data of different segments in different gender were significantly differences(P<0.05). The maximal extraversion angle in lumbar spine increased gradually from (33.41±1.31) degree to (56.53±4.71) degree in males, as same as in females from(28.58±2.55) to (53.86±2.68) degree. There was no crossing point in area A, 3.3% of males and 26.67% of females in area B, rest in area C. The distribution areas on gender showed statistically significance (P<0.05). CONCLUSIONS: Backward rotation method can theoretically meet the requirements of puncture point for vertebral compression fracture, especially for males and lower lumbar spine. The determination of the maximum inclination angle is of guiding significance to the backward rotation method.


Asunto(s)
Fracturas por Compresión , Cifoplastia , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Femenino , Humanos , Vértebras Lumbares , Masculino , Punciones , Rotación , Vértebras Torácicas , Resultado del Tratamiento
11.
J Phys Condens Matter ; 30(38): 385702, 2018 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-30106004

RESUMEN

We present high-resolution thermal-expansion and specific-heat measurements of single crystalline α-RuCl3. An extremely hysteretic structural transition expanding over 100 K is observed by thermal-expansion along both crystallographic axes, which we attribute to a change of stacking sequence of the RuCl3 layers. Three magnetic transitions are observed, which we link to the different stacking sequences. Using our data and thermodynamic relations, we derive the uniaxial and hydrostatic pressure derivatives of all three magnetic transitions. Our results demonstrate that magnetic order of the major transition at ∼7 K should be totally suppressed by very moderate pressures of 0.3 GPa. Finally, we discuss why our results differ from recent hydrostatic pressure measurements and suggest a possible route to reaching the spin-liquid state in α-RuCl3.

12.
Zhongguo Zhen Jiu ; 37(3): 259-264, 2017 Mar 12.
Artículo en Chino | MEDLINE | ID: mdl-29231431

RESUMEN

OBJECTIVE: To observe the effects of micro-invasive embedding combined with montelukast sodium and simple montelukast sodium for children cough variant asthma (CVA). METHODS: A total of 240 patients were randomly assigned into an observation group and a control group, 120 cases in each one. Considering of cases dropping, 101 patients in the observation group and 105 cases in the control group were included. Montelukast sodium chewable tablets were applied before sleep for 3 months in the control group, 5 mg a time, once a day. Based on the treatment as the control group, micro-invasive embedding was used for 3 months in the observation group, twice in the first month and once in the other two months. The acupoints were Feishu (BL 13), Danzhong (CV 17), Dingchuan (EX-B 1), and Zusanli (ST 36). Follow-up was conducted 9 months after treatment in the two groups. The cough score, serum immunoglobulin (IgE, IgG, IgA), platelet activating factor (PAF) were observed before and after treatment. The indices were compared before and after treatment and at follow-up, including pulmonary function indices[peak expiratory flow rate (PEF), forced expiratory volume at the 1st second (FEV1)], and small airway function indices[forced expiratory flow rate with remaining 25% vital capacity (MEF25%), forced expiratory flow rate with remaining 50% vital capacity (MEF50%), forced expiratory flow rate with remaining 75% vital capacity (MEF75%) and mid expiratory flow rate (MEF25%-75%)]. Also, the total effects were evaluated. RESULTS: ①The total effective rate in the observation group was 93.1% (94/101), which was better than 87.6% (92/105) in the control group (P<0.05). The cough disappearance time of the cured children in the observation group was (10.38±2.64) d, and it was shorter than (10.72 ±2.60) d of those in the control group (P<0.05). After treatment, the cough score apparently decreased compared with those before treatment in the two groups (both P<0.05), with better result in the observation group (P<0.05). At follow-up, the recurrence frequency of the observation group was (1.43±1.20), and it was less than (1.91±1.71) in the control group (P<0.05). ②The levels of serum IgA and IgG after treatment in the two groups increased, and those of serum IgE and PAF decreased, compared with those before treatment. There was statistically significance except IgG in the control group before and after treatment (all P<0.05), with better Results in the observation group after treatment (all P<0.05). ③ Compared with those before treatment, all the pulmonary function indices were improved obviously after treatment and at follow-up in the two groups (all P<0.05), without statistically significance between the two groups (both P>0.05). ④ There was no statistically significance before and after treatment on small airway function indices in the two groups (all P>0.05). The indices at follow-up increased compared with those before treatment in the two groups (all P<0.05), with better Results in the observation group (all P<0.05). CONCLUSIONS: Micro-invasive embedding combined with montelukast sodium achieved de-finite effect for children CVA, which can improve the body's immune and microcirculation. The effect is better than that of simple montelukast sodium on improving small airway function, etc.


Asunto(s)
Acetatos/uso terapéutico , Terapia por Acupuntura/métodos , Antiasmáticos/uso terapéutico , Asma/terapia , Tos/terapia , Quinolinas/uso terapéutico , Puntos de Acupuntura , Niño , Ciclopropanos , Volumen Espiratorio Forzado , Humanos , Sulfuros
13.
Nat Commun ; 8(1): 504, 2017 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-28894127

RESUMEN

High-temperature superconductivity in the Fe-based materials emerges when the antiferromagnetism of the parent compounds is suppressed by either doping or pressure. Closely connected to the antiferromagnetic state are entangled orbital, lattice, and nematic degrees of freedom, and one of the major goals in this field has been to determine the hierarchy of these interactions. Here we present the direct measurements and the calculations of the in-plane uniform magnetic susceptibility anisotropy of BaFe2As2, which help in determining the above hierarchy. The magnetization measurements are made possible by utilizing a simple method for applying a large symmetry-breaking strain, based on differential thermal expansion. In strong contrast to the large resistivity anisotropy above the antiferromagnetic transition at T N, the anisotropy of the in-plane magnetic susceptibility develops largely below T N. Our results imply that lattice and orbital degrees of freedom play a subdominant role in these materials.Interplay between lattice, orbital, magnetic and nematic degrees of freedom is crucial for the superconductivity in Fe-based materials. Here, the authors demonstrate the subdominant roles of pure lattice distortions and/or orbital ordering in BaFe2As2 by characterizing the in-plane magnetic susceptibility anisotropy.

14.
Zhongguo Gu Shang ; 30(1): 93-96, 2017 Jan 25.
Artículo en Chino | MEDLINE | ID: mdl-29327560

RESUMEN

As a common type of fracture in cervical, atlas fracture is frequently unstable due to its special anatomical structure. In a previous treatment, external fixation was likely to bring low bony union rate and long-term neck pain, while occipito-cervical fusion and atlantoaxial fusion sacrifice range of motion in cervical spine. Reduction and single section fixation of atlas by anterior lateral mass screws through the transoral approach were reported by some scholars, and the retrospective study demonstrated the high healing rate, reservation of cervical ROM and less bleeding. But it also has high risks of cervical spinal cord and vertebral artery damage, as well as the post-operation infection. Moreover, the indication and fixation strength require further evidences. As a result, this surgical option provides a new way for spinal surgeons to deal with unstable atlas fractures.


Asunto(s)
Articulación Atlantoaxoidea/cirugía , Atlas Cervical/lesiones , Fracturas de la Columna Vertebral/cirugía , Fusión Vertebral , Fijación Interna de Fracturas , Humanos , Estudios Retrospectivos
15.
Eur Spine J ; 25(6): 1716-23, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26931331

RESUMEN

STUDY DESIGN: We evaluated the trajectory and the entry points of anterior transpedicular screws (ATPS) in the cervicothoracic junction (CTJ). OBJECTIVE: This study aimed at investigating the feasibility of ATPS fixation in the CTJ. Application of an ATPS in the lower cervical spine has been reported; however, there were no reports exploring the feasibility of anterior transpedicular screw fixation in the CTJ. METHODS: CT scans were performed in 50 cases and multiplanar reformation was used to measure the related parameters on pedicle axis view at C6-T2. Transverse pedicle angle, outer pedicle width, pedicle axis length, distance transverse intersection point (DtIP), sagittal pedicle angle, anterior vertebral body height, outer pedicle height, and distance sagittal intersection point (DsIP) were measured. The prozone of CTJ was divided into three different regions, which were named as the "manubrium region", the region "above" and "below" the manubrium. The distribution of the trajectory of sagittal pedicle axes was recorded in the three regions and the related data were statistically analyzed. RESULTS: There was no statistical difference in gender (P > 0.05). The transverse pedicle angle decreased from C6 (46.77° ± 2.72°) to T2 (20.62° ± 5.04°). DtIP increased from C6 to T2. DsIP was an average of 7.17 mm. The sagittal pedicle axis lines of the C6 and C7 were located in the region above the manubrium. T1 was mainly in the manubrium region followed by the region above the manubrium. T2 was mainly located in the manubrium region followed by the region below the manubrium. CONCLUSION: Implantation of ATPS at C6, C7, and some T1 is feasible through the low anterior cervical approach, while it is almost impossible to approach T2 that way.


Asunto(s)
Vértebras Cervicales/cirugía , Procedimientos Ortopédicos , Tornillos Pediculares , Vértebras Torácicas/cirugía , Adulto , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Ortopédicos/instrumentación , Procedimientos Ortopédicos/métodos , Procedimientos Ortopédicos/estadística & datos numéricos , Tomografía Computarizada por Rayos X , Adulto Joven
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 63(3): 614-8, 2006 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-16455294

RESUMEN

High qualities Raman spectra of pyridine carboxylic acid in silver colloidal solution and on silver-coated ITO glass at near infrared laser excitation were obtained in this article. The calculations based on density functional theory (DFT) were used to analysis the absorption behavior of these molecules. By comparing the experimental frequencies with the calculated ones, it can be concluded that the carboxylate-to-metal interaction is the key factor during the adsorption process, and the nitrogen-to-metal coordination seemed to play a secondary role in the process.


Asunto(s)
Ácidos Carboxílicos/química , Nanoestructuras/química , Piridinas/química , Plata/química , Espectrofotometría/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Adsorción , Coloides/química , Simulación por Computador , Ácidos Isonicotínicos/química , Modelos Químicos , Niacina/química , Programas Informáticos , Espectrofotometría Infrarroja , Espectrometría Raman
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 62(4-5): 958-63, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16303634

RESUMEN

Ag nanoparticles, organized on indium tin oxide (ITO) surface, can act as a new surface enhanced Raman scattering (SERS) active substrate as well as a dry electrode. Compared with the traditional SERS-active substrate, its notable advantage is that the microcosmic changes of the film can be reflected by the SERS spectrum during the investigation of the film's electrical and other macroscopic characteristics. To illuminate the above-mentioned property of this new substrate, a series of n-hydroxybenzoic acids (n-HBA; n=p, m and o) was tested as probe molecules by SERS technique. These SERS spectra indicate that the significant changes of frequencies as well as intensities, respectively, arise from the changes of the adsorption behavior along with the proportional variation of molecules and silver nanoparticles. Excellent SERS signals prove that the silver nanoparticles-coated ITO is a highly SERS-active substrate and can efficiently reflect the microcosmic property of the film, which suggest it has promising potential of being a new technique for further application in the field of thin-film research.


Asunto(s)
Hidroxibenzoatos/química , Espectrometría Raman/métodos , Coloides/química , Dispersión de Radiación , Plata , Espectroscopía Infrarroja por Transformada de Fourier , Compuestos de Estaño/química
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