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1.
Cancer Invest ; 39(5): 369-378, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33886387

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors combined with endocrine therapy (ET) for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER-2-) advanced breast cancer (ABC) patients. METHODS: We searched clinical trials of CDK4/6 inhibitors combined with ET and calculated the clinical outcomes. RESULTS: HR+/HER-2- ABC patients treated with CDK4/6 inhibitors combined with ET had significantly prolonged progression-free survival (PFS) and improved objective response rate (ORR) and clinical benefit rate (CBR). CONCLUSIONS: CDK4/6 inhibitors combined with ET can bring more clinical benefits to ABC patients, and the safety profile is acceptable.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Receptores de Estrogênio/uso terapêutico , Receptores de Progesterona/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Feminino , Humanos
2.
Nano Lett ; 19(6): 3432-3439, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-30608711

RESUMO

Controlling the spin angular momentum of light (or circular polarization state) plays a crucial role in the modern photonic applications such as optical communication, circular dichroism spectroscopy, and quantum information processing. However, the conventional approaches to manipulate the spin of light require naturally occurring chiral or birefringent materials of bulky sizes due to the weak light-matter interactions. Here we experimentally demonstrate an approach to implement spin-selective transmission in the infrared region based on chiral folded metasurfaces that are capable of transmitting one spin state of light while largely prohibiting the other. Due to the intrinsic chirality of the folded metasurface, a remarkable circular dichroism as large as 0.7 with the maximum transmittance exceeding 92% is experimentally demonstrated. The giant circular dichroism is interpreted within the framework of charge-current multipole expansion. Moreover, the intrinsic chirality can be readily controlled by manipulating the folding angle of the metasurface with respect to the cardinal plane. Benefiting from its strong chirality and spin-dependent transmission characteristics, the proposed folded metasurface may be applied to a range of novel photon-spin selective devices for optical communication technologies and biophotonics.

3.
Nano Lett ; 19(7): 4551-4559, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31241975

RESUMO

With strong spin-orbit coupling (SOC), ultrathin two-dimensional (2D) transitional metal chalcogenides (TMDs) are predicted to exhibit weak antilocalization (WAL) effect at low temperatures. The observation of WAL effect in VSe2 is challenging due to the relative weak SOC and three-dimensional (3D) transport nature in thick VSe2. Here, we report on the observation of quasi-2D transport and WAL effect in sublimed-salt-assisted low-temperature chemical vapor deposition (CVD) grown few-layered high-quality VSe2 nanosheets. The WAL magnitudes in magnetoconductance can be perfectly fitted by the 2D Hikami-Larkin-Nagaoka (HLN) equation in the presence of strong SOC, by which the spin-orbit scattering length lSO and phase coherence length lϕ have been extracted. The phase coherence length lϕ shows a power law dependence with temperature, lϕ∼ T-1/2, revealing an electron-electron interaction-dominated dephasing mechanism. Such sublimed-salt-assisted growth of high-quality few-layered VSe2 and the observation of WAL pave the way for future spintronic and valleytronic applications.

4.
Nano Lett ; 16(11): 6870-6878, 2016 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-27786486

RESUMO

The capabilities to tune the conduction properties of materials by doping or electric fields are essential for the design of electronic devices. However, in two-dimensional materials substitutional doping has been achieved in only a few systems, such as Nb substitutional doping in MoS2. Surface charge transfer is still one of the popular ways to control whether the conduction is dominated by holes or electrons. Here, we demonstrate that a capping layer of cross-linked poly(methyl methacrylate) modifies the potential in a black phosphorus (BP) layer so that conduction in the absence of an external electric field is dominated by electrons, rather than holes. Using this technique to form adjoining regions dominated by hole and electron conduction, a family of novel planar devices, such as BP-gated diodes, BP bidirectional rectifier, and BP logic inverters, can be fabricated. The devices are potentially useful for electronic applications, including rectification and switching.

5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 41(4): 302-305, 2017 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-29862796

RESUMO

The craniospinal radiotherapy method was studied by using the whole body positioning frame and base dose plan compensation (BDPC) technique.11 patients with central nervous system malignancies in our hospital were studied. Use whole body positioning frame with the head-neck shoulder and body membrane to immobilize posture, then use BDPC for the intensity-modulated radiotherapy. Target area conformability index(CI), homogeneity index (HI), dose of endangerment organ (OAR) and beam connecting dose distribution are evaluated. The use of base-dosecompensation intensity-modulated plan combined with whole-body positioning technology improves the target area conformability and target uniformity, simplifies the design of craniospinal radiotherapy, improves the placement accuracy and ensure good placement repeatability. We measure beam connecting dose distribution. Cold and hot spots do not appear, and calculated values are basically identical. The application of whole-body positioning technique combined with BDPC optimization method in the treatment of the craniospinal radiotherapy meets the clinical requirements of dosimetry. Moreover, it is simple and can improve the treatment planning efficiency.


Assuntos
Radiação Cranioespinal , Radioterapia de Intensidade Modulada , Humanos , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
6.
J Nanosci Nanotechnol ; 13(2): 1199-202, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23646602

RESUMO

The movement of the magnetic domain wall could result in the changing of the contact resistance. Such a resistance change is named as the domain wall Magnetoresistance (DWMR), which can be used as a basic signal of nanodevices. For application, a large DWMR is necessary to improve the device performance. An approach to improve the DWMR value is to fabricate magnetic structures with narrow contact width. However, due to the proximity effect during the process of electron beam lithography (EBL), it is not easy to fabricate sub-20 nm width structures by EBL technique directly. In this paper, we investigated the fabrication of sub-20 nm width nanocontact structures by combined techniques of EBL and shadow evaporation. Upon optimizing the resist thickness, opening width, and the evaporation angle, the contact width was tuned and the corresponding variation trends with these parameters were explored. Using the optimized fabrication conditions, 14 nm wide ferromagnetic contact structures were successfully fabricated.

7.
Eur J Med Res ; 28(1): 470, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37898776

RESUMO

BACKGROUND: Insulin resistance (IR) had been reported to be associated with age; however, few studies have explored the association between IR and biological age (BA). The HOMA-IR value is a useful indicator of the extent of IR. This cross-sectional study is to explore the relationship between HOMA-IR and BA/advanced aging in the US population. METHODS: This study is a cross-sectional analysis of National Health and Nutrition Examination Survey (NHANES) data. The survey comprised 12,266 people from the NHANES, and their full HOMA-IR data as well as BA data were extracted. Four multiple linear regressions were performed to analyze the association between HOMA-IR and BA, and four multiple logistic regression models were performed to analyze the association between HOMA-IR and advanced aging. In addition, trend tests and stratified analysis were performed and smoothed fitted curves were plotted to test the robustness of the results. RESULTS: HOMA-IR was positively correlated with BA [ß: 0.51 (0.39, 0.63)], and it was the same to advanced aging [OR: 1.05 (1.02, 1.07)], and both showed a monotonically increasing trend. The trend tests showed that the results were stable (all P for trend < 0.0001). The smoothed fitted curves showed that there were non-linear relationships between HOMA-IR and BA/advanced aging. And the stratified analysis indicated that the relationship between HOMA-IR and BA/advanced aging remained robust in all subgroups. CONCLUSION: The study suggested that HOMA-IR is positively correlated with BA and advanced aging in the US adult population, with a monotonic upward trend. This is a new finding to reveal the relationship between HOMA-IR and age from new standpoint of BA rather than chronological age (CA). And it may contribute to a better understanding of human health aging and may aid future research in this field.


Assuntos
Resistência à Insulina , Adulto , Humanos , Estudos Transversais , Inquéritos Nutricionais , Envelhecimento , Inquéritos e Questionários
8.
Nanotechnology ; 23(27): 275503, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22706679

RESUMO

Metamaterials (MMs) have shown huge potential in sensing applications by detecting their optical properties, which can be designed to operate at frequencies from visible to mid-IR. Here we constructed complementary split ring resonator (CSRR) based metamaterials in nanoscale with unit length of 100 nm and slit width of 30 nm, and observed obvious responses in the visible waveband from 600 to 900 nm. These visible responses show a good tunability with the structure's geometry, and are well suited for dielectric detection. We demonstrated good refractive index sensing of CSRR based metamaterials in the visible region under both 0° and 90° polarized incidence. Our results extend the study of CSRR based metamaterials to the visible region, which is expected to deepen the understanding of the response mechanism of CSRRs and benefit their sensing applications in the visible region.


Assuntos
Nanopartículas/química , Nanopartículas/ultraestrutura , Nanotecnologia/instrumentação , Refratometria/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
9.
Micromachines (Basel) ; 13(6)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35744470

RESUMO

Three-dimensional (3D) nanostructures have attracted widespread attention in physics, chemistry, engineering sciences, and biology devices due to excellent functionalities which planar nanostructures cannot achieve. However, the fabrication of 3D nanostructures is still challenging at present. Reliable fabrication, improved controllability, and multifunction integration are desired for further applications in commercial devices. In this review, a powerful fabrication method to realize 3D nanostructures is introduced and reviewed thoroughly, which is based on atomic layer deposition assisted 3D assembly through various sacrificial templates. The aim of this review is to provide a comprehensive overview of 3D nanofabrication based on atomic layer assembly (ALA) in multifarious sacrificial templates for 3D nanostructures and to present recent advancements, with the ultimate aim to further unlock more potential of this method for nanodevice applications.

10.
Mol Biol Rep ; 38(2): 929-37, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20495874

RESUMO

RNA-dependent RNA polymerases (RDRs) play an important role in RNA silencing, antiviral and developmental progress. Here, we firstly isolated the full-length cDNA, genomic DNA and 5'-flanking region of RDR6 from Nicotiana glutinosa (NgRDR6). Sequences analysis revealed that the cDNA of NgRDR6 was 3,921 bp in length, and the deduced protein consisted of 1,197 amino acids, containing all highly conserved sequence motifs that are present among all RDRs families. Moreover, two introns were detected in the genomic sequences. We also firstly investigated the expression profiles of plant RDR6 under the treatments of gibberellin A (GA), H(2)O(2,) methyl jasmonate (MeJA), Potato virus Y (PVY), Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV), Rhizoctonia Solani and Colletotrichum nicotianae. In addition, the expression patterns of RDR6 in Nicotiana glutinosa under the treatments of salicylic acid (SA) and abscisic acid (ABA) were also been analyzed. The results indicated that the NgRDR6 mRNA accumulation could be induced by ABA, GA, MeJA, CMV, Rhizoctonia Solani and Colletotrichum nicotianae. In contrast, the expression level of NgRDR6 exhibited no remarkable difference under the treatments of PVY, TMV, H(2)O(2) and SA. Further investigation suggested several potential cis-acting elements were found in the 5'-flanking sequence of NgRDR6, which might be responsible for the enhanced response to phytohormones.


Assuntos
Proteínas de Arabidopsis/genética , Nicotiana/enzimologia , Nicotiana/genética , RNA Polimerase Dependente de RNA/genética , Acetatos/química , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Ciclopentanos/química , Primers do DNA/genética , DNA Complementar/metabolismo , Perfilação da Expressão Gênica , Giberelinas/química , Peróxido de Hidrogênio/química , Dados de Sequência Molecular , Oxilipinas/química , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
11.
J Am Chem Soc ; 132(3): 944-6, 2010 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-20030310

RESUMO

We report that gold thermally deposited onto n-layer graphenes interacts differently with these substrates depending on the number layer, indicating the different surface properties of graphenes. This results in thickness-dependent morphologies of gold on n-layer graphenes, which can be used to identify and distinguish graphenes with high throughput and spatial resolution. This technique may play an important role in checking if n-layer graphenes are mixed with different layer numbers of graphene with a smaller size, which cannot be found by Raman spectra. The possible mechanisms for these observations are discussed.


Assuntos
Ouro/química , Grafite/química , Membranas Artificiais , Nanopartículas Metálicas/química , Tamanho da Partícula , Silício/química , Dióxido de Silício/química , Propriedades de Superfície
12.
J Nanosci Nanotechnol ; 10(11): 7138-41, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21137882

RESUMO

In this paper, we report the fabrication of permalloy nanocontact structures with greatly improved surface and edge smoothness. Magnetic sputtering and thermal evaporation were used for metal film deposition, and lift-off and dry etching techniques were employed for nanocontact structure patterning. The compositional properties of the resulting nanocontacts were investigated using energy dispersive analysis of X-ray (EDAX). Atom force microscope and scanning electron microscope were used for morphological characterisation. We found that high quality permalloy nanocontact structures can be obtained by using the combination of thermal evaporation and lift-off with optimised processing parameters; meanwhile, in the case of depositing metal films using magnetic sputtering, dry etching technique rather than lift-off was used for improved surface morphology of the nanostructures.

13.
J Nanosci Nanotechnol ; 10(11): 7300-2, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21137919

RESUMO

Nanopores embedded in a thin membrane with diameter below 10 nm are suitable for the biomacromolecule detection. For such purpose, in this study, we developed a technique of how to obtain small nanopores in silicon nitride films using a focused-ion-beam (FIB) system. By changing the process parameters, such as the beam current, the film thickness of the membrane and the ion beam exposure time, the diameter of the nanopore can be tuned. Under an optimized condition, high quality nanopores with diameter as low as 6 nm was fabricated on a 7 nm thick membrane. Our result suggests that FIB direct writing technique might be a suitable approach for biomacromolecule detector fabrication.


Assuntos
DNA/análise , Nanoporos , Microscopia Eletrônica de Transmissão
14.
J Nanosci Nanotechnol ; 10(11): 7477-80, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21137963

RESUMO

Carbon nanotubes, particularly multiwall carbon nanotubes (MWCNTs) can serve as interconnects in nanoelectronic devices and integrated circuits because of their extremely large current-carrying capacity. Many experimental results about the transport properties of individual MWCNTs by contacting outer shell or all shells have been reported. In this work, a compatible method with integrated circuit manufacturing process was presented to compare the transport property of an individual multiwall carbon nanotube (MWCNT) by contacting outer shell only and all shells successively. First of the Ti/Au electrodes contacting outer shell only were fabricated onto the nanotube through the sequence of electron beam lithography (EBL) patterning, metal deposition and lift-off process. After the characterization of its transport property, focused ion beam (FIB) was used to drill holes through the same nanotube at the as-deposited electrodes. Then new contact to the holes and electrodes were made by ion-induced deposition of tungsten from W(CO)6 precursor gas. The transport results indicated that the new contact to all shells can clear up the intershell resistance and the electrical conductance of the tube can be improved about 8 times compared to that of by contacting outer shell only.

15.
Zookeys ; 996: 37-58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33312045

RESUMO

In this study, four new dextral camaenid from China are reported, based on shell morphology, reproductive system anatomy, and molecular phylogenetic analyses: Camaena funingensis Zhou, Wang & Lin, sp. nov., Camaena gaolongensis Zhou, Wang & Lin, sp. nov., Camaena maguanensis Zhou, Wang & Hu, sp. nov., and Camaena yulinensis Zhou, Wang & Hu, sp. nov. Detailed descriptions of the morphological characteristics including shells and genitalia, DNA sequences, and living environments of the four new species are provided, with further comparisons with congeners.

16.
Integr Med Res ; 9(4): 100431, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32637314

RESUMO

BACKGROUND: The evidence of Acupuncture combined with speech rehabilitation training for post-stroke dysarthria is insufficient and there is no consensus on its efficacy. METHODS: We searched seven Chinese and English medicine databases for randomized controlled trials (RCTs) from their inception to November 2019. The primary outcome measure was the clinical response rate, assessed with the Frenchay Dysarthria Assessment (FDA) tool. We assessed risk of bias using the Cochrane risk-of-bias tool. We used GRADE to assess the certainty of evidence (CoE). RESULTS: Thirty studies were included in this systematic review, 23 of which were pooled in meta-analysis. Acupuncture combined with speech rehabilitation training is likely beneficial for was response rate (n = 1685; RR = 1.37; 95% CI [1.29, 1.46], P < 0.01, I 2 = 34%; 17 studies, low CoE) compared to speech rehabilitation treatment alone. CONCLUSION: The combination of acupuncture and speech rehabilitation training may improve total response rate of stroke patients with dysarthria. However, more RCTs with rigorous study design and validated outcome measures are needed to confirm the evidence.

17.
J Nanosci Nanotechnol ; 9(2): 1119-22, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19441468

RESUMO

Zinc oxide nanowires were grown on molybdenum grids with a simple chemical vapor transport and deposition method through thermal evaporation of zinc powder at a temperature of 600 degrees C. These nanowires are 20-50 nm in diameter and over ten microns in length. High resolution transmission electron microscopy studies show that the as-grown nanowires are single crystal of wurtzite structure and grow along the (0001) direction. The growth process was explained with a vapor-solid mechanism under zinc-rich conditions. We further patterned electrodes on individual ZnO nanowires by e-beam lithography and studied thier electrical properties.

18.
Hortic Res ; 5: 23, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29736248

RESUMO

Litchi is one of the most important subtropical evergreen fruit trees in southern Asia. Previous studies indicated that high-temperature conditions encourage growth of rudimentary leaves in panicles and suppress flowering. We have demonstrated that methyl viologen dichloride hydrate (MV) and sodium nitroprusside (SNP) promoted flowering in litchi partially by inhibiting the growth of rudimentary leaves via reactive oxygen species (ROS) and nitric oxide (NO). In the present study, we examined the microstructure and ultrastructure, programmed cell death (PCD) ratio, nuclei morphology of the rudimentary leaves, and the expression of senescence-related genes after the treatment with ROS or NO. The results showed that chromatins of the ROS- or NO-treated cells in the rudimentary leaves were condensed. Fusion of the cytoplasm-digesting vesicles with the vacuole and degradation of cytoplasm forming scattered debris were found in those of the treated cells. Treatment with ROS or NO increased the cell PCD ratio. Morphology of the nuclei stained by propidium iodide (PI) showed that nuclei shape became irregular after the ROS or NO treatment. Further, the expression levels of LcRboh, LcMC-1-like, and LcPirin were higher in the ROS- and NO-treated rudimentary leaves than those in the control ones, suggesting that these genes may be involved in the ROS and NO-induced senescence and abscission of the rudimentary leaves in litchi. Our results suggested that ROS and NO play an important role in inducing the senescence of the rudimentary leaves, and ROS- and NO-induced PCD may be involved in the regulation of the rudimentary leaf growth in litchi.

19.
Sci Rep ; 7(1): 15590, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29142227

RESUMO

The phylogeographic structure of the land snail Camaena cicatricosa was analyzed in this study based on mitochondrial gene (COI and 16srRNA, mt DNA) and internal transcribed spacer (ITS2) sequences in 347 individuals. This snail is the vector of the zoonotic food-borne parasite Angiostrongylus cantonensis and one of the main harmful snails distributed exclusively in China. The results revealed significant fixation indices of genetic differentiation and high gene flow between most populations except several populations. An isolation-by-distance test showed no significant correlation between genetic distance and geographical distance among C. cicatricosa populations, which suggested that gene flow was not restricted by distance. The levels of haplotype and nucleotide diversity of C. cicatricosa were generally high, except those in some special populations, according to the mt DNA and ITS2 data. Furthermore, the phylogenetic trees and asteroid networks of haplotypes indicated nonobvious genetic structure, the same as results got based on the synonymous and non synonymous sites of 347 sequences of the COI gene. All lines of evidence indicated that climatic changes and geographical and human barriers do not substantially affect the current population structure and distribution of the investigated snails.


Assuntos
DNA Intergênico/genética , DNA Mitocondrial/genética , Genética Populacional , Caramujos/genética , Animais , China , Estruturas Genéticas , Variação Genética/genética , Haplótipos/genética , Humanos , Filogeografia , RNA Ribossômico 16S/genética
20.
Opt Express ; 14(21): 10014-20, 2006 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-19529395

RESUMO

An in-plane, three-port filter consisting of input/output waveguides and two point-defect cavities in a 2D PC slab is designed and fabricated, where a new feedback method is introduced, and its transmission properties are measured. The measured minimum output wavelength spacing between two channels is 1.5 nm, which is realized by slightly adjusting the size of the resonant cavities. The measured resonant wavelengths of two cavities agree well with the calculated ones and the quality factors of the cavities are almost the same. It is believed that this kind of filter may be useful in optical integrated circuits with high density.

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