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1.
Nano Lett ; 24(1): 67-73, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38149785

RESUMO

Two-dimensional transition metal nitrides offer intriguing possibilities for achieving novel electronic and mechanical functionality owing to their distinctive and tunable bonding characteristics compared to other 2D materials. We demonstrate here the enabling effects of strong bonding on the morphology and functionality of 2D tungsten nitrides. The employed bottom-up synthesis experienced a unique substrate stabilization effect beyond van-der-Waals epitaxy that favored W5N6 over lower metal nitrides. Comprehensive structural and electronic characterization reveals that monolayer W5N6 can be synthesized at large scale and shows semimetallic behavior with an intriguing indirect band structure. Moreover, the material exhibits exceptional resilience against mechanical damage and chemical reactions. Leveraging these electronic properties and robustness, we demonstrate the application of W5N6 as atomic-scale dry etch stops that allow the integration of high-performance 2D materials contacts. These findings highlight the potential of 2D transition metal nitrides for realizing advanced electronic devices and functional interfaces.

2.
Small ; 20(17): e2307728, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263806

RESUMO

Herein, the structure of integrated M3D inverters are successfully demonstrated where a chemical vapor deposition (CVD) synthesized monolayer WSe2 p-type nanosheet FET is vertically integrated on top of CVD synthesized monolayer MoS2 n-type film FET arrays (2.5 × 2.5 cm) by semiconductor industry techniques, such as transfer, e-beam evaporation (EBV), and plasma etching processes. A low temperature (below 250 °C) is employed to protect the WSe2 and MoS2 channel materials from thermal decomposition during the whole fabrication process. The MoS2 NMOS and WSe2 PMOS device fabricated show an on/off current ratio exceeding 106 and the integrated M3D inverters indicate an average voltage gain of ≈9 at VDD = 2 V. In addition, the integrated M3D inverter demonstrates an ultra-low power consumption of 0.112 nW at a VDD of 1 V. Statistical analysis of the fabricated inverters devices shows their high reliability, rendering them suitable for large-area applications. The successful demonstration of M3D inverters based on large-scale 2D monolayer TMDs indicate their high potential for advancing the application of 2D TMDs in future integrated circuits.

3.
BMC Pregnancy Childbirth ; 24(1): 401, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822253

RESUMO

BACKGROUND: Previous studies had found that the mechanical methods were as effective as pharmacological methods in achieving vaginal delivery. However, whether balloon catheter induction is suitable for women with severe cervical immaturity and whether it will increase the related risks still need to be further explored. RESEARCH AIM: To evaluate the efficacy and safety of Foley catheter balloon for labor induction at term in primiparas with different cervical scores. METHODS: A total of 688 primiparas who received cervical ripening with a Foley catheter balloon were recruited in this study. They were divided into 2 groups: Group 1 (Bishop score ≤ 3) and Group 2 (3 < Bishop score < 7). Detailed medical data before and after using of balloon were faithfully recorded. RESULTS: The cervical Bishop scores of the two groups after catheter placement were all significantly higher than those before (Group 1: 5.49 ± 1.31 VS 2.83 ± 0.39, P<0.05; Group 2: 6.09 ± 1.00 VS 4.45 ± 0.59, P<0.05). The success rate of labor induction in group 2 was higher than that in group 1 (P<0.05). The incidence of intrauterine infection in Group 1 was higher than that in Group 2 (18.3% VS 11.3%, P<0.05). CONCLUSION: The success rates of induction of labor by Foley catheter balloon were different in primiparas with different cervical conditions, the failure rate of induction of labor and the incidence of intrauterine infection were higher in primiparas with severe cervical immaturity.


Assuntos
Maturidade Cervical , Colo do Útero , Trabalho de Parto Induzido , Humanos , Trabalho de Parto Induzido/métodos , Feminino , Gravidez , Estudos Retrospectivos , Adulto , Paridade , Cateterismo/métodos , Nascimento a Termo , Adulto Jovem , Cateterismo Urinário/métodos , Cateterismo Urinário/instrumentação , Catéteres
4.
BMC Pregnancy Childbirth ; 24(1): 164, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408955

RESUMO

BACKGROUND: The causes of some stillbirths are unclear, and additional work must be done to investigate the risk factors for stillbirths. OBJECTIVE: To apply the International Classification of Disease-10 (ICD-10) for antepartum stillbirth at a referral center in eastern China. METHODS: Antepartum stillbirths were grouped according to the cause of death according to the International Classification of Disease-10 (ICD-10) criteria. The main maternal condition at the time of antepartum stillbirth was assigned to each patient. RESULTS: Antepartum stillbirths were mostly classified as fetal deaths of unspecified cause, antepartum hypoxia. Although more than half of the mothers were without an identified condition at the time of the antepartum stillbirth, where there was a maternal condition associated with perinatal death, maternal medical and surgical conditions and maternal complications during pregnancy were most common. Of all the stillbirths, 51.2% occurred between 28 and 37 weeks of gestation, the main causes of stillbirth at different gestational ages also differed. Autopsy and chromosomal microarray analysis (CMA) were recommended in all stillbirths, but only 3.6% received autopsy and 10.5% underwent chromosomal microarray analysis. CONCLUSIONS: The ICD-10 is helpful in classifying the causes of stillbirths, but more than half of the stillbirths in our study were unexplained; therefore, additional work must be done. And the ICD-10 score may need to be improved, such as by classifying stillbirths according to gestational age. Autopsy and CMA could help determine the cause of stillbirth, but the acceptance of these methods is currently low.


Assuntos
Classificação Internacional de Doenças , Natimorto , Gravidez , Feminino , Humanos , Natimorto/epidemiologia , Estudos Retrospectivos , Morte Fetal/etiologia , Encaminhamento e Consulta , Causas de Morte
5.
J Pediatr Orthop ; 44(6): e490-e495, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38533533

RESUMO

BACKGROUND: The shape of the labrum is strongly correlated with outcomes of developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) is the generally preferred imaging technique for observing the labrum. PURPOSE: We aimed to find a correlation between the labrum shape and anterior-posterior (AP) pelvic measurements in children with DDH. METHODS: Preoperative AP pelvic x-ray radiographs and MRI of patients with DDH from January 2019 to December 2021 were retrospectively collected and divided into three groups by labrum shape on MRI: everted, partly inverted, and inverted. The acetabular length ratio (RAL) in patients with unilateral DDH and the ratio of acetabular length to interpedicular distance (RALI) in all patients were calculated. T-tests were used to analyze differences between the groups. Receiver operating characteristic curve (ROC) analysis was performed between the everted group and the partly inverted and inverted groups. RESULTS: We found significant differences in RAL between the everted and partly inverted groups, everted and inverted groups, and everted and combined groups. The ROC analysis showed that the best cutoff value for RAL was 0.945 between the everted and combined groups, with an area under the curve (AUC) of 88.4%. The sensitivity at the best RAL value was 0.783, and the specificity was 0.887. Moreover, we observed a significant difference in RALI between the everted, partly inverted, and inverted groups, as well as between the everted and combined groups. The optimal cutoff value for RALI between the everted and combined groups was 0.575, with an AUC of 74.5%. The sensitivity at the best RALI value was 0.765, and the specificity was 0.674. CONCLUSION: The RAL or RALI values on pelvic AP radiographs can be used to predict the shape of the labrum. LEVEL OF EVIDENCE: III.


Assuntos
Acetábulo , Displasia do Desenvolvimento do Quadril , Imageamento por Ressonância Magnética , Radiografia , Humanos , Estudos Retrospectivos , Feminino , Masculino , Displasia do Desenvolvimento do Quadril/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Acetábulo/diagnóstico por imagem , Radiografia/métodos , Lactente , Pré-Escolar , Curva ROC
6.
J Org Chem ; 88(23): 16547-16555, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37971809

RESUMO

A photocatalytic three-component reaction of a nitroarene, a thiophenol, and a ketone for the synthesis of multifunctional diaryl sulfides was reported using a nitro group as the nitrogen source and thiophenol as the sulfur source. Thiophenol also serves as a proton donor to reduce nitroarene to arylamine as a key intermediate for the formation of C-N and C-S bonds. Good functional group tolerance and mild reaction conditions make this method have practical synthetic value for diversified multifunctional diaryl sulfides.

7.
Org Biomol Chem ; 21(47): 9341-9345, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37987693

RESUMO

A visible light-enabled cascade cyclization strategy is disclosed with concomitant phosphorylation and heterocycle construction. It provides a novel and environmentally benign approach for accessing tetrahydroindolizine-containing phosphonates under metal-free conditions. Mechanistic studies revealed that phosphinoyl radicals were generated from H-phosphonates via a HAT process.

8.
J Asian Nat Prod Res ; 25(11): 1085-1096, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36951955

RESUMO

The efficient total synthesis of anti-tumor natural product pongaflavone (1) was described starting from commercially available 2,4-dihydroxyacetophenone (9) via seven steps and in 16% overall yield. Its two natural analogues pongachromene (2) and 7,8-(2",2"-dimethylpyrano)-5,3',4'-trihydroxy-3-methoxyflavone (3) were also synthesized following the similar procedure with the yields of 11% and 18%, respectively. Their preliminary anti-tumor activities were evaluated by the inhibition effect on A549 cells. The result showed that this kind of natural products exhibited different levels of anti-tumor activity. Among them, pongachromene (2) displayed the best anti-tumor activity.


Assuntos
Produtos Biológicos , Flavonoides , Flavonoides/síntese química
9.
Int Orthop ; 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37442823

RESUMO

PURPOSE: Hip vessel examination provides key information on many hip-related pediatric diseases, and it has an important role in the evaluation of femoral head (FH) blood supply and diagnosis of avascular necrosis (AVN). The aim of this study was to investigate the feasibility of MR-enhanced high-resolution three-dimensional water-selective cartilage (3D-WATSc) sequence in visualizing the vessels of the hip joint in children. PATIENTS AND METHODS: Children with hip disease were randomly enrolled prospectively at our hospital from January 2021 to August 2022. We performed our institution's hip MRI protocol and enhanced high-resolution 3D-WATSc sequence. The 3D-WATSc images were reconstructed and analyzed, and images of the normal hip were categorized into grades 0-3. The abnormal hip images were compared with those of the normal side using the χ2 test. RESULTS: Twenty-four patients with unilateral hip abnormalities were included in this study. The cartilaginous vascular canal and ossification centre vessels of normal FHs were observed in 18 patients (75%) and met the grade 3 standard. An abnormal cartilaginous canal was observed in 16 patients (67%); meanwhile, 18 patients (75%) had abnormal extrachondral vessels. Comparison of high-resolution 3D-WATSc images with those of the normal side provided effective abnormal vascular information in 95.8% of patients. CONCLUSIONS: Enhanced high-resolution 3D-WATSc can visualize the blood vessels of the hip in children. This may provide a new method for the vascular study of various pediatric hip diseases.

10.
J Formos Med Assoc ; 121(1 Pt 2): 329-334, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34045124

RESUMO

BACKGROUND/PURPOSE: Voice therapy is frequently recommended as the first-line treatment for benign voice disorders. This study investigated the clinical effectiveness of voice therapy and the prognostic factors of treatment outcomes. METHODS: We recruited 103 consecutive patients with voice disorders, namely vocal nodules, polyps, and muscle tension dysphonia (MTD), from September 2014 to July 2016. All the patients received voice therapy as the primary treatment. Treatment outcomes were evaluated using auditory perceptual evaluation, acoustic analysis, maximum phonation time, and 10-item voice handicap index (VHI-10). Clinical effectiveness of voice therapy was defined by either 1) a posttreatment VHI-10 score ≤ 10 points or 2) decline of VHI-10 ≥ 4 points. RESULTS: After voice therapy, VHI-10 and perceptual rating of voice quality improved significantly (p < 0.05) in the three disease categories. In patients with nodules, all the outcome parameters improved significantly (p < 0.05). Patients with good adherence to voice therapy (attending more than four sessions) had a significantly higher effectiveness than those with poor adherence (87% vs. 64%, p < 0.05). Patients with high occupational vocal demand also demonstrated a better effectiveness than those with routine vocal demand (90% vs. 70%, p < 0.05). Subsequent multivariate analyses revealed that adherence and vocal demand were independently and significantly correlated with clinical effectiveness (p = 0.03). CONCLUSION: Voice therapy is effective for patients with vocal nodules, polyps, and MTD. Adherence to voice therapy and occupational vocal demand are significant prognostic factors for treatment outcomes.


Assuntos
Distúrbios da Voz , Humanos , Prognóstico , Resultado do Tratamento , Distúrbios da Voz/terapia
11.
Int J Mol Sci ; 23(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35163506

RESUMO

Pancreatic adenocarcinoma (PAC) is the 8th leading cause of cancer-related deaths in Taiwan, and its incidence is increasing. The development of PAC involves successive accumulation of multiple genetic alterations. Understanding the molecular pathogenesis and heterogeneity of PAC may facilitate personalized treatment for PAC and identify therapeutic agents. We performed tumor-only next-generation sequencing (NGS) with targeted panels to explore the molecular changes underlying PAC patients in Taiwan. The Ion Torrent Oncomine Comprehensive Panel (OCP) was used for PAC metastatic lesions, and more PAC samples were sequenced with the Ion AmpliSeq Cancer Hot Spot (CHP) v2 panel. Five formalin-fixed paraffin-embedded (FFPE) metastatic PAC specimens were successfully assayed with OCP, and KRAS was the most prevalent alteration, which might contraindicate the use of anti-EGFR therapy. One PAC patient harbored a FGFR2 p. C382R mutation, which might benefit from FGFR tyrosine kinase inhibitors. An additional 38 samples assayed with CHP v2 showed 100 hotspot variants, collapsing to 54 COSMID IDs. The most frequently mutated genes were TP53, KRAS, and PDGFRA (29, 23, 10 hotspot variants), impacting 11, 23, and 10 PAC patients. Highly pathogenic variants, including COSM22413 (PDGFRA, FATHMM predicted score: 0.88), COSM520, COSM521, and COSM518 (KRAS, FATHMM predicted score: 0.98), were reported. By using NGS with targeted panels, somatic mutations with therapeutic potential were identified. The combination of clinical and genetic information is useful for decision making and precise selection of targeted medicine.


Assuntos
Adenocarcinoma/genética , Povo Asiático/genética , Mutação , Neoplasias Pancreáticas/genética , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Metástase Neoplásica , Estudos Prospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Estudos Retrospectivos , Taiwan , Proteína Supressora de Tumor p53/genética , Neoplasias Pancreáticas
12.
Zhongguo Zhong Yao Za Zhi ; 47(4): 922-930, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285191

RESUMO

The present study explored the kinetics and variation of volatile components of Atractylodis Macrocephalae Rhizoma during the hot-air drying process to obtain the optimal process parameters under multiple goals such as drying efficiency and drying quality. The dry basis moisture content and drying rate curves along with the change of drying time of Atractylodis Macrocephalae Rhizoma were investigated at five levels of drying air temperatures(30, 40, 50, 60, and 70 ℃). The relationship between moisture ratio and time in the drying process of Atractylodis Macrocephalae Rhizoma was fitted and verified by Midilli model, Page model, Overhults model, Modified Page model, Logaritmic model, Two terms Exponential model, and Newton model. Meanwhile, the effective diffusion coefficient of moisture(D_(eff)) and activation energy(E_a) in Atractylodis Macrocephalae Rhizoma were calculated under different drying air temperatures. GC-MS was used to determine the volatile components and content changes of the fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures. The dry basis moisture content and drying rate of Atractylodis Macrocephalae Rhizoma were closely related to the temperature of the drying medium, and the moisture of the Atractylodis Macrocephalae Rhizoma decreased with the prolonged drying time. As revealed by the drying rate curve, the drying rate increased with the increase in hot air temperature, and the migration of moisture was accelerated. The comparison of the correlation coefficient(R~2), chi-square(χ~2), and root mean standard error(RMSE) of each model indicated that the parameter average of the Midilli model had the highest degree of fit, with R~2=0.999 2, χ~2=8.78×10~(-5), and RMSE=8.20×10~(-3). Besides, the D_(eff) at 30-70 ℃ was in the range of 1.04×10~(-9)-6.28×10~(-9) m~2·s~(-1), and E_a was 37.47 kJ·mol~(-1). The volatile components of fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures were determined by GC-MS, and 18, 18, 18, 17, 17, and 18 compounds were identified respectively, which accounted for more than 84.76% of the volatile components. In conclusion, the hot-air drying of Atractylodis Macrocephalae Rhizoma can be model-fitted and verified and the variation law of the moisture and volatile components of Atractylodis Macrocephalae Rhizoma with temperature is obtained. This study is expected to provide new ideas for exploring the drying characteristics and quality of aromatic Chinese medicine.


Assuntos
Atractylodes , Medicamentos de Ervas Chinesas , Temperatura Alta , Cinética , Rizoma
13.
J Org Chem ; 86(3): 2474-2488, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33415975

RESUMO

We present an efficient and versatile visible light-driven methodology to transform aryl aldehydes and ketones chemoselectively either to alcohols or to pinacol products with CdSe/CdS core/shell quantum dots as photocatalysts. Thiophenols were used as proton and hydrogen atom donors and as hole traps for the excited quantum dots (QDs) in these reactions. The two products can be switched from one to the other simply by changing the amount of thiophenol in the reaction system. The core/shell QD catalysts are highly efficient with a turn over number (TON) larger than 4 × 104 and 4 × 105 for the reduction to alcohol and pinacol formation, respectively, and are very stable so that they can be recycled for at least 10 times in the reactions without significant loss of catalytic activity. The additional advantages of this method include good functional group tolerance, mild reaction conditions, the allowance of selectively reducing aldehydes in the presence of ketones, and easiness for large scale reactions. Reaction mechanisms were studied by quenching experiments and a radical capture experiment, and the reasons for the switchover of the reaction pathways upon the change of reaction conditions are provided.

14.
Inorg Chem ; 60(24): 18990-19000, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34851093

RESUMO

Single-molecule magnets (SMMs) are expected to be promising candidates for the applications of high-density information storage materials and quantum information processing. Lanthanide SMMs have attracted considerable interest in recent years due to their excellent performance. It has always been interesting but not straightforward to study the relaxation and blocking mechanisms by embedding 3d ions into 4f SMMs. Here we report a family of air-stable 3d-4f ion-pair compounds, YFe (1), DyCr (2), DyFe (3), DyCo (4), and Dy0.04Y0.96Fe (5), composed of pentagonal bipyramidal (D5h) LnIII cations and transition metallocyanate anions. The ion-pair nature makes the dipole-dipole interactions almost the only component of the magnetic interactions that can be clarified and analytically resolved under proper approximation. Therefore, this family provides an intuitive opportunity to investigate the effects of 3d-4f and 4f-4f magnetic interactions on the behavior of site-resolved 4f SMMs. Dynamic magnetic measurements of 1 under a 4 kOe external field reveal slow magnetic relaxation originating from the isolated [FeIII]LS (S = 1/2) ions. Under zero dc field, compounds 2-5 show similar magnetic relaxation processes coming from the separated pentagonal bipyramidal (D5h) DyIII ions with high Orbach barriers of 592(5), 596(4), 595(3), and 606(4) K, respectively. Comparatively, both compounds 3 and 5 exhibit two distinct relaxation processes, respectively from the [FeIII]LS and DyIII [Ueff = 596(4) K for 3 and 610(7) K for 5] ions, under a 4 kOe dc field. The dipolar interactions between the neighboring TMIII (TM = transition metal, CrIII or [FeIII]LS) and DyIII ions were revealed to have little effect on the thermal relaxation in compounds 2, 3, and 5, or the coexistence of the two separate relaxation processes in compounds 3 and 5 under a 4 kOe dc field, but they significantly affect the quantum tunneling of magnetization and the magnetic hysteresis behavior of 2 and 3 at low temperatures compared to those of 4.

15.
Phys Chem Chem Phys ; 23(38): 21489-21495, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550130

RESUMO

Controllable fabrication of enantiospecific molecular superlattices is a matter of imminent scientific and technological interest. Herein, we demonstrate that long-range superlattice chirality in molecular self-assemblies can be tailored by tuning the interplay of weak intermolecular non-covalent interactions between hexaphenylbenzene-based enantiomers. By means of high-resolution scanning tunneling microscopy measurements, we demonstrate that the functionalization of a hexaphenylbenzene-based molecule with fluorine (F) atoms leads to the formation of molecular self-assemblies with distinct long-range chiral recognition patterns. We employed density functional theory calculations to quantify F-mediated lone pair F⋯π, C-H⋯F, and F⋯F interactions attributed to the distinct enantiospecific molecular self-organizations. Our findings underpin a viable route to fabricate long-range chiral recognition patterns in supramolecular assemblies by engineering the weak non-covalent intermolecular interactions.

16.
BMC Med Imaging ; 21(1): 160, 2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717585

RESUMO

BACKGROUND: Enhancement profiles of the pulmonary artery (PA) and aorta differ when using computed tomography (CT) angiography. Our aim was to determine the optimal CT protocol for a one-time CT scan that assesses both blood vessels. METHODS: We prospectively enrolled 101 cases of CT angiography in patients with suspected pulmonary embolism or aortic dissection from our center between 2018 and 2020. We also retrospectively collected the data of 40 patients who underwent traditional two-time CT scans between 2015 and 2018. Patients were divided into four groups: test bolus (TB) I, TB II, bolus-tracking (BT) I, and BT II. The enhancement of the PA and aorta, and the radiation doses used in the four groups were collected. Those who underwent two-time scans were classified into the traditional PA or aorta scan groups. Data were compared between the BT and traditional groups. RESULTS: The aortic enhancement was highest in BT II (294.78 ± 64.48 HU) followed BT I (285.18 ± 64.99 HU), TB II (186.58 ± 57.53 HU), and TB I (173.62 ± 69.70 HU). The radiation dose used was lowest in BT I (11.85 ± 5.55 mSv) and BT II (9.07 ± 3.44 mSv) compared with that used in the traditional groups (20.07 ± 7.78 mSv) and accounted for half of the traditional group (45.17-59.02%). The aortic enhancement was also highest in BT II (294.78 ± 64.48 HU) followed by BT I (285.18 ± 64.99 HU) when compared with that in the traditional aorta scan group (234.95 ± 94.18 HU). CONCLUSION: Our CT protocol with a BT technique allows for a lower radiation dose and better image quality of the PA and aorta than those obtained using traditional CT scans. TRIAL REGISTRATION: NCT04832633, retrospectively registered in April 2021 to the clinical trial registry.


Assuntos
Aneurisma Aórtico/diagnóstico por imagem , Dissecção Aórtica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Embolia Pulmonar/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Estudos Retrospectivos
17.
Surg Innov ; 28(5): 552-559, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33393435

RESUMO

Objectives. In this study, we performed a novel type of posterior en bloc elevation cervical laminoplasty (PEEL) to keep the integrity of the posterior structure, aiming to reduce axial symptoms complicated by a conventional cervical laminoplasty procedure. Methods. Twelve human cervical cadaveric spines (C2-T1) were sequentially tested in the following order: intact condition, open-door laminoplasty (ODL) through bilateral intermuscular approach (mini-invasive ODL), PEEL, and laminectomy (LN). After bilateral transecting at the junction of lamina and lateral mass through the tubular retraction system, the PEEL procedure symmetrically elevated all the posterior structure which was further stabilized with bone grafts and titanium plates. Computed tomography (CT) scan and biomechanical testing were performed after each condition. Results. Both mini-invasive ODL and PEEL procedures were accomplished with 2 small incisions on each side. Two types of laminoplasties could enlarge the spinal canal significantly both in cross-sectional area and anteroposterior diameter comparing with intact condition. The PEEL procedure demonstrated a significantly higher enlargement rate on a canal area and a symmetrical expansion pattern. Compared with intact condition, mini-invasive ODL performed from C3-C7 demonstrated significantly decreased motion in all testing directions except the flexion range of motion (ROM); the PEEL procedure showed mild and insignificant decrease on ROM in all directions. Laminectomy resulted in a statistically significant increase in all directions except the lateral bending ROM. Conclusions. Posterior en bloc elevation cervical laminoplasty can enlarge the canal more effectively and preserve better ROM after operation than the ODL procedure. Although technically challenging, the PEEL procedure probably would decrease the common complications associated with ODL laminoplasty.


Assuntos
Laminoplastia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Humanos , Laminectomia , Pescoço , Amplitude de Movimento Articular , Resultado do Tratamento
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(1): 98-103, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33474897

RESUMO

OBJECTIVE: R6G-ddATP was used as a dideoxy fluorescence substrate to establish the single base end extension (SNaPShot)-gel fluorescence method for the rapid detection of the genotypes of three high-risk human papillomaviruses (HR-HPV) ( HPV18, HPV33 and HPV35) genotypes. METHODS: HPV quality control products were used as as samples, and R6G-ddATP dideoxy fluorescence reagent was used as substrate. Firstly, HPV was amplified by using universal primers to obtain the first round of amplified products, which were purified and used as templates for subsequent SNaPShot reactions. Then, specific one-step extension primers were used to perform SNaPShot reaction to generate R6G-fluorescence-labeled DNA extension products. The product was subjected to agarose gel electrophoresis, the results of which were observed under a Gel Imager, and the HPV genotyping was done with different one-step extension primers. Each sample was tested three times and the results were compared with DNA sequencing results. RESULTS: The preferred annealing temperature for SNaPShot reaction is 55 ℃. Three HPV genotypes were examined by R6G-ddATP/SNaPShot gel fluorescence assay under optimal conditions, and the results were consistent with DNA sequencing results. CONCLUSION: The R6G-ddATP/SNaPShot-gel fluorescence method for the micro-detection methods of three HR-HPV genotypes was successfully established and can be used for rapid detection of HPV genotypes.


Assuntos
Alphapapillomavirus , Papillomaviridae , Infecções por Papillomavirus , DNA Viral/genética , Nucleotídeos de Desoxiadenina , Didesoxinucleotídeos , Genótipo , Humanos , Papillomaviridae/genética , Reação em Cadeia da Polimerase
19.
Small ; 16(15): e1904271, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32196957

RESUMO

Recently, 2D transition metal dichalcogenides (TMDs) have become intriguing materials in the versatile field of photonics and optoelectronics because of their strong light-matter interaction that stems from the atomic layer thickness, broadband optical response, controllable optoelectronic properties, and high nonlinearity, as well as compatibility. Nevertheless, the low optical cross-section of 2D-TMDs inhibits the light-matter interaction, resulting in lower quantum yield. Therefore, hybridizing the 2D-TMDs with plasmonic nanomaterials has become one of the promising strategies to boost the optical absorption of thin 2D-TMDs. The appeal of plasmonics is based on their capability to localize and enhance the electromagnetic field and increase the optical path length of light by scattering and injecting hot electrons to TMDs. In this regard, recent achievements with respect to hybridization of the plasmonic effect in 2D-TMDs systems and its augmented optical and optoelectronic properties are reviewed. The phenomenon of plasmon-enhanced interaction in 2D-TMDs is briefly described and state-of-the-art hybrid device applications are comprehensively discussed. Finally, an outlook on future applications of these hybrid devices is provided.

20.
Phys Rev Lett ; 124(3): 036402, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32031832

RESUMO

Platinum ditelluride (PtTe_{2}), a type-II Dirac semimetal, remains semimetallic in ultrathin films down to just two triatomic layers (TLs) with a negative gap of -0.36 eV. Further reduction of the film thickness to a single TL induces a Lifshitz electronic transition to a semiconductor with a large positive gap of +0.79 eV. This transition is evidenced by experimental band structure mapping of films prepared by layer-resolved molecular beam epitaxy, and by comparing the data to first-principles calculations using a hybrid functional. The results demonstrate a novel electronic transition at the two-dimensional limit through film thickness control.

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