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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(4): 339-345, 2024 Apr 12.
Artigo em Zh | MEDLINE | ID: mdl-38599809

RESUMO

Objective: To construct and characterize conditional Src homology region 2 protein tyrosine phosphatase 1 (SHP-1) knockout mice in airway epithelial cells and to observe the effect of defective SHP-1 expression in airway epithelial cells on the emphysema phenotype in chronic obstructive pulmonary disease (COPD). Methods: To detect the expression of SHP-1 in the airway epithelium of COPD patients. CRISPR/Cas9 technology was used to construct SHP-1flox/flox transgenic mice, which were mated with airway epithelial Clara protein 10-cyclase recombinase and estrogen receptor fusion transgenic mice (CC10-CreER+/+), and after intraperitoneal injection of tamoxifen, airway epithelial SHP-1 knockout mice were obtained (SHP-1flox/floxCC10-CreER+/-, SHP-1Δ/Δ). Mouse tail and lung tissue DNA was extracted and PCR amplified to discriminate the genotype of the mice; the knockout effect of SHP-1 gene in airway epithelial cells was verified by qRT-PCR, Western blotting, and immunofluorescence. In addition, an emphysema mouse model was constructed using elastase to assess the severity of emphysema in each group of mice. Results: Airway epithelial SHP-1 was significantly downregulated in COPD patients. Genotyping confirmed that SHP-1Δ/Δ mice expressed CC10-CreER and SHP-1-flox. After tamoxifen induction, we demonstrated the absence of SHP-1 protein expression in airway epithelial cells of SHP-1Δ/Δ mice at the DNA, RNA, and protein levels, indicating that airway epithelial cell-specific SHP-1 knockout mice had been successfully constructed. In the emphysema animal model, SHP-1Δ/Δ mice had a more severe emphysema phenotype compared with the control group, which was manifested by disorganization of alveolar structure in lung tissue and rupture and fusion of alveolar walls to form pulmonary alveoli. Conclusions: The present study successfully established and characterized the SHP-1 knockout mouse model of airway epithelial cells, which provides a new experimental tool for the in-depth elucidation of the role of SHP-1 in the emphysema process of COPD and its mechanism.


Assuntos
Enfisema , Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Humanos , Camundongos , Animais , Enfisema Pulmonar/genética , Enfisema Pulmonar/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Células Epiteliais/metabolismo , Camundongos Transgênicos , Camundongos Knockout , Fenótipo , DNA , Tamoxifeno
2.
Zhonghua Yi Xue Za Zhi ; 101(30): 2382-2386, 2021 Aug 10.
Artigo em Zh | MEDLINE | ID: mdl-34404131

RESUMO

Objective: To investigate the effect of axillary lymph node status on the prognosis of different types of invasive breast cancer. Methods: Patients with invasive breast cancer of different molecular subtypes diagnosed in the breast cancer prevention and treatment center of Beijing Cancer Hospital from January 2000 to July 2011 were collected as a historical cohort, and the influence of lymph node status on the prognosis of different types of breast cancer was analyzed. Results: A total of 4 269 female breast cancer patients with molecular subtypes [aged (50.8±11.2) years] information and 3 824 female breast cancer patients with complete axillary lymph node status information [aged (50.5±10.9) years] were included in the study, including 3 135 cases with both molecular subtypes and lymph node status information. The 10-year event free survival (EFS) rates of hormone receptor (HR)+/human epidermal growth factor receptor-2(HER2)-, HR-/HER2-and HER2+were 82.2%, 79.0% and 76.8%, respectively; the 10-year overall survival (OS) rates were 88.1%, 83.1% and 84.4%, respectively, and the differences of 3 molecular subtypes in EFS and OS were statistically significant (both P<0.001). The 10-year EFS rate of lymph node positive and negative patients was 68.8% and 88.2%, respectively; the 10-year OS rate was 76.7% and 92.5%, respectively, and the differences of lymph node status in EFS and OS were statistically significant (both P<0.001). In lymph node negative subgroup, 3 subtypes showed similar EFS and OS rate (both P>0.05); In lymph node positive subgroup, 3 subtypes showed significantly different EFS and OS (both P<0.05). No modification effect was detected of lymph node status on the correlation of molecular subtypes and EFS, DDFS and OS(all Pinteractive>0.1). Conclusions: Different molecular subtypes of breast cancer have different prognosis. Compared with molecular subtype, lymph node status may be a more important prognostic factor.


Assuntos
Neoplasias da Mama , Axila , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos , Prognóstico , Receptor ErbB-2
3.
Zhonghua Wai Ke Za Zhi ; 59(2): 127-133, 2021 Feb 01.
Artigo em Zh | MEDLINE | ID: mdl-33378805

RESUMO

Objective: To examine the difference of long-term recurrence rate and survivals between the young patients and the old patients undergoing breast conserving therapy (BCT). Methods: Women with primary invasive breast cancer receiving BCT between December 1999 and December 2014 were selected retrospectively from the database of Breast Cancer Center, Peking University Cancer Hospital & Institute. The median age of all patients was 47 years (range: 21 to 91 years). The cases were categorized according to age at diagnosis into two subgroups: the ≤40 years group and the>40 years group. A total of 2 778 patients were included: 677 patients in the ≤40 years group and 2 101 patients in the >40 years group. Clinicopathological characteristics between two groups were compared. The recurrence rate and survival were calculated using the Kaplan-Meier method. The differences of outcomes were compared in different aged groups using the Log-rank test. Factors affecting local recurrence, distant disease-free survival (DDFS), disease-free survival (DFS), and breast cancer-specific survival (BCSS) were assessed by multivariable Cox proportional hazard models. Results: Proportions of T1 (301/677 vs. 1 160/2 101, χ²=37.660, P<0.01), involved lymph node (314/677 vs. 713/2 101, χ²=34.966, P<0.01) hormone receptor-negative (490/677 vs. 1 581/2 101, χ²=6.981, P=0.030) and neoadjuvant chemotherapy (413/677 vs. 1 010/2 101, χ²=34.272,P<0.01)in the ≤40 years group were higher than that in the>40 years group. Median follow-up duration was 102 months. No significant difference in 10-year local recurrence was found between the two groups (2.5% vs. 1.6%, P=0.147). Ten-year DDFS rate in the ≤40 years group and in the>40 years group was 90.6% and 95.3%, respectively (P<0.01). Ten-year DFS rate in the ≤40 years group and in the>40 years group was 86.5% and 91.1%, respectively (P=0.001). Ten-year BCSS rate in the ≤40 years group and in the >40 years group was 91.0% and 93.7%, respectively (P=0.105). Age was not the prognosis factor of local recurrence. Lymph node status (positive vs. negative: HR=2.73, 95%CI: 1.94 to 3.84, P<0.01), age (≤40 years vs.>40 years: HR=1.73, 95%CI: 1.24 to 2.42, P=0.001) and T stage (>2 cm vs. ≤2 cm: HR=1.61, 95%CI: 1.14 to 2.28, P=0.001) were the prognosis factors of DDFS, and also for DFS. Hormone receptor status (positive vs. negative: HR=0.54, 95%CI: 0.39 to 0.74, P<0.01), lymph node status (positive vs. negative: HR=2.94, 95%CI: 2.12 to 4.07, P<0.01) and T stage (>2 cm vs. ≤2 cm: HR=1.45, 95%CI: 1.05 to 2.01, P=0.025) were the prognosis factors of BCSS. Conclusions: The risk of local recurrence was similar between ≤40 years patient and >40 years patients receiving breast conserving therapy. Worse survivals in the ≤40 years group were found comparing to those in the >40 years group.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Recidiva Local de Neoplasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
4.
Nanotechnology ; 31(31): 315206, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32299069

RESUMO

Recently, the arsenic monolayer has been successfully fabricated by micromechanical stripping. However, it is a non-magnetic semiconductor, including its derivatives. Here, we theoretically explore how to induce magnetism for arsenene armchair nanotubes (AsANTs) with a low-concentration TM (TM = Co, Y, Rh, Ni, Mo, Ru) atom doping, especially focusing on their structural stability, magneto-electronic property, carrier mobility, and strain effects. The high stability of these doped tubes are confirmed by the calculated binding energy and formation energy, as well as Forcite annealing molecular dynamics simulations. The AsANT can act as bandgap narrowed non-magnetic semiconductors or highly spin-polarized magnetic semiconductors (half-semiconductor or bipolar magnetic semiconductor) depending on TM types, suggesting different promising applications such as developing infrared photodetectors with broadband detectionin or spintronic devices. The magnetic thermal stability beyond room temperature is predicted for doped tubes. Furthermore, the carrier mobility of AsANTs can be tuned into a wide region by TM doping, but it is enhanced in most cases. The carrier and spin polarity of mobility can also be clearly observed. Particularly, the applied strain can induce a rich magnetic phase transition among a half-semiconductor, half-metal, bipolar magnetic semiconductor and nonmagnetic state. Furthermore, the presented stepwise change of total magnetic moment between high magnetized and nonmagnetic states is highly desirable for engineering a mechanical switch which can reversibly work between magnetism and demagnetism to control spin-polarized transport by applying strain.

5.
Phys Chem Chem Phys ; 22(41): 23665-23677, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33112338

RESUMO

Antimonene nanotubes, a class of important derivatives of the 2D counterpart (Sb monolayer), with transition metal (TM) atom adsorption were investigated systematically based on the first-principles calculations. For a stable geometry, the lengths of TM-Sb bonds on the tube surface strongly depend on their relative electronegativity. In particular, we find that the intrinsic magnetic moment magnitude of the TM atom plays a decisive role in inducing tube magnetism, and only TM atoms with a larger intrinsic magnetic moment (≥3.0 µB) can induce the magnetism for tubes. The strong interaction and coupling between the TM d-orbital and Sb p-orbital lead to variously favorable magnetic phases, such as the spin bipolar semiconductor and half-semiconductor, which is predicted to be stable beyond room temperature. In addition, the weakening or quenching of the magnetism for the adsorbed TM atom is intimately related to the expansion of the TM atom valence electron configuration and the charge transfer. Furthermore, the TM adsorption can also effectively regulate the tube carrier mobility to the difference of several orders of magnitude, and results in significant carrier polarity and spin polarity of mobility. A sensitive electric-magnetic coupling effect was also shown to cause continuous magnetic phase transition, providing more opportunity for obtaining magneto-electric materials.

6.
Zhonghua Zhong Liu Za Zhi ; 42(8): 682-686, 2020 Aug 23.
Artigo em Zh | MEDLINE | ID: mdl-32867462

RESUMO

Objective: To analyze the safety and short-term efficacy of breast-conserving surgery combined with intraoperative radiotherapy for early-stage breast cancer. Methods: A total of 101 consecutive patients who received breast-conserving surgery plus intraoperative radiotherapy were recruited to summarize the recent follow-up results and clinicopathological data. Univariate analysis and Logistic regression model were used to evaluate the factors affecting the postoperative adverse reactions and cosmetic effects. Results: Among 101 patients, 4 patients had recurrence or metastasis. The 3-years disease free survival rate was 94.9%, and the 3-years cumulative recurrence rate was 5.1%. Univariate analysis showed that the menstrual status and postoperative whole breast radiotherapy were associated with the postoperative adverse reactions (P<0.05). The T stage and applicator diameter were associated with the cosmetic effect (P<0.05). Multivariate analysis indicated that the diameter of the applicator (OR=3.701, P=0.026) and postoperative whole breast radiotherapy (OR=5.962, P=0.005) were independent factors for the postoperative adverse reactions, and the diameter of the applicator (OR=2.522, P=0.037) was an independent factor for the cosmetic effect. Conclusion: Breast-conserving surgery combined with intraoperative radiotherapy shows safety and good short-term efficacy in low-risk early-stage breast cancer.


Assuntos
Neoplasias da Mama/terapia , Mastectomia Segmentar , Radioterapia Adjuvante/métodos , Neoplasias da Mama/patologia , Terapia Combinada , Humanos , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Resultado do Tratamento
7.
Nanotechnology ; 30(14): 145201, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30593010

RESUMO

Phosphorene and its derivatives so far have attracted substantial research interest due to its promising properties for developing nanoscale electronic devices. Here, we present a theoretical investigation on the functionalized features, such as the improved electronic structure and carrier mobility, for armchair-edged single walled black phosphorus nanotubes (PNTs) with the substitutional doping of low-concentration transition-metal atoms (Ti, Mn, Fe, and Ni). They are predicted to be exceptional magnetic semiconductors (MSCs), such as half-semiconductor or bipolar MSC. Their spin-resolved carrier mobility at room temperature holds doping element- dependence as well as carrier and spin polarity. Particularly, the difference by two orders of magnitude for carrier mobility emerges due to different TM doping. More interestingly, the carrier mobility in armchair PNTs serving as the channel material of a spin field effect transistor is predicted to be modified strongly by a gate voltage. The enhanced carrier mobility and its gate voltage direction-dependent behavior, as well as the more obvious carrier and spin polarity of mobility, can be observed clearly under gate voltage, which further facilitates the separation of different carriers and spin states and also suggests that realistic carrier mobility is gate voltage-dependent in a field effect transistor.

8.
Nanotechnology ; 30(48): 485703, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31426048

RESUMO

Recently, a new type of quasi-1D graphene-like nanoribbons, periodically embedded with four- and eight- membered rings, has been successfully fabricated, and based on this structure, a novel planar 2D carbon allotrope, the so-called the net-Y, has been proposed. Here, we study various nanoribbons derived from such a 2D monolayer focusing on the structure stability, electronic, and transport properties, especially on the physical field coupling effects of electronic behaviors. Very high stability is predicted for various types of nanoribbons by the calculated binding energy and molecular dynamics simulation. Different edge shapes and widths have a significant influence on their electronic properties. Armchair nanoribbons are always semiconductors, and possess a high carrier mobility. After hydrogen termination, some metallic nanoribbons can become semiconductors or quasi-metals with massless Dirac-fermion behavior. In particular, the electronic properties of ribbons can be effectively modulated by applying strain and electric field. The band gap size and the transition from indirect to direct band gap can be realized upon strain or electric field. These flexibly tunable electronic properties for nanoribbons expand their applications in nanoelectronics and optoelectronics.

9.
Phys Chem Chem Phys ; 21(4): 1830-1840, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30629061

RESUMO

Functionalizing graphene to develop on-demand nanodevices is highly desirable, but still remains challenging. Here, we theoretically propose the functionalization of armchair graphene nanoribbons by low-concentration metal (M) atom (M = Ti, Ni, Sn, or Hg) doping and investigate the structural stability and electronic behaviors of these doped systems in depth. The calculated binding energy and formation energy as well as the molecular dynamics simulation show that the geometries of these hybridized ribbons are rather stable. With metal doping, the ribbons present rich and flexibly tunable bandgaps, depending on the metal atom and doping position, which can be attributed to newly emerged hybridized subbands near the Fermi level and the entire energy band structure shifting upward due to the increased electron number in the ribbon donated from the dopant. These bandgaps can also be further tuned substantially by the stress. And the carrier mobility is calculated based on the deformation potential theory, which shows that the different metal doping can effectively control the carrier mobility, and a large carrier polarity can also be clearly observed. Furthermore, the metal doping can significantly enhance the device properties of the ribbon as compared with those of the pristine ribbon, such as creating a large negative differential resistance phenomenon. These studies demonstrate that these doping systems might hold promising applications in nano-electronics.

10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(3): 267-271, 2019 Mar 06.
Artigo em Zh | MEDLINE | ID: mdl-30841665

RESUMO

Objective: To analyze the attributable burden of smoking on the deaths of cardio-cerebral vascular diseases (CCVD) in inhabitants aged 30 years and above in Jiangsu Province. Methods: Comparative risk assessment approach in Global Burden of Disease (GBD) was used with the data from Jiangsu Non-communicable Disease and Behavioral Risk Factor Surveillance System and Death Monitoring Surveillance System in 2013, and population attributable fraction (PAF), years of life lost (YLL), work of potential years of life lost, index of life lost and life loss attributed to smoking were calculated. Results: In 2013, there were 162 158 CCVD deaths aged 30 years and above in the surveillance areas of Jiangsu Province, of which 25 102 deaths were attributed to smoking (PAF: 15.48%, attributed mortality rate: 55.13/100 000). The YLL, work of potential years of life lost and index of life lost were 532 494 person years, 78 024 person years and 9.15 years respectively. The decline of life expectancy was 0.58 years. The PAF of CCVD attributed to smoking in male and female were 27.97% and 3.18%, respectively, and the mortality rate of cardio-cerebral diseases attributed to smoking in male and female were 100.13/100 000 and 11.27/100 000, respectively. The burden of ischemic heart disease and hemorrhagic stroke were most severe, with standardized YLL rate were 3.65‰ and 3.20‰, respectively. Conclusion: Smoking caused a great burden of cardio-cerebral disease deaths in inhabitants in Jiangsu province.


Assuntos
Doenças Cardiovasculares/mortalidade , Transtornos Cerebrovasculares/mortalidade , Fumar/efeitos adversos , Adulto , Causas de Morte , China/epidemiologia , Feminino , Humanos , Masculino
11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(2): 218-222, 2019 Feb 06.
Artigo em Zh | MEDLINE | ID: mdl-30744300

RESUMO

Objective: To evaluate the risk of 10-year risk of ischemic cardiovascular disease (ICVD) in patients with type 2 diabetes aged 35 years old and above in two cities of Jiangsu province. Methods: From December 2013 to January 2014, a total of 15 624 patients with type 2 diabetes aged 35 years old and above, who received national basic public health service in Changshu county of Suzhou city, Huai'an and Qinghe districts of Huai'an city, Jiangsu province, were recruited by cluster sampling method. Face-to-face questionnaire survey, anthropometric and laboratory measurements were conducted to collect exposures to ICVD risk factors. Improved Ten Year Risk Assessment Table of ICVD in Chinese was used to assess the risk score and the absolute risk of developing ICVD. Results: The participants were (62.2±9.7) years old, of which 6 137 were men (39.3%). Among the participants, the highest rate of exposure to ICVD risk factors was high systolic blood pressure (74.8%, n=11 685), followed by high total cholesterol (70.7%, n= 11 051).The score of 10-year risk for ICVD was (10.4±3.3) and the median (P(25)-P(75)) value of absolute risk was 15.6% (6.8%-32.7%). 16.7% (n=2 602) participants were under extremely high risk of 10-year risk for ICVD, 23.8% (n=3 714) under high-risk and 24.0% (n=3 746) under middle-risk. Among the total risk score of ICVD, age (49.1%), hypertension (17.7%) and diabetes (15.5%) accounted for relatively high proportion, however, smoking (11.0%) was the most important risk factor except for age (47.4%) and systolic blood pressure (20.5%) in male participants. Conclusion: Patients with type 2 diabetes aged 35 years old and above in two cities of Jiangsu Province have a high risk of developing ICVD for 10 years, especially in elderly, female, hypertension patients and male smokers.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Isquemia Miocárdica/epidemiologia , Adulto , Idoso , China/epidemiologia , Cidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Phys Chem Chem Phys ; 20(19): 13574-13579, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29736547

RESUMO

One-dimensional phosphorus nanotubes (PNTs) are important derivatives of phosphorene. Herein, the magneto-electronic properties for PNTs doped with low-concentration transition metals (TM) (Fe, Co, and Ni) both in their inner and outer layers were investigated in detail. TM-PNTs are very stable with high structural integrity and versatile magnetic properties. In particular, some important magnetic properties such as half-metallic and dilute magnetic semiconducting behaviors can be observed, which are the basis of the application of TM-PNTs in spintronics. Furthermore, the electric field can induce magnetic phase transitions and demagnetization can occur under a very low electric field due to Co-doping in the outer layer of the PNTs. This interesting feature is very attractive for constructing electric-field-controllable magnetic/nonmagnetic switch devices that are operated in two possible states.

13.
Zhonghua Yi Xue Za Zhi ; 98(4): 260-263, 2018 Jan 23.
Artigo em Zh | MEDLINE | ID: mdl-29397610

RESUMO

Objective: To construct a dynamic enhanced MR based predictive model for early assessing pathological complete response (pCR) to neoadjuvant therapy in breast cancer, and to evaluate the clinical benefit of the model by using decision curve. Methods: From December 2005 to December 2007, 170 patients with breast cancer treated with neoadjuvant therapy were identified and their MR images before neoadjuvant therapy and at the end of the first cycle of neoadjuvant therapy were collected. Logistic regression model was used to detect independent factors for predicting pCR and construct the predictive model accordingly, then receiver operating characteristic (ROC) curve and decision curve were used to evaluate the predictive model. Results: ΔArea(max) and Δslope(max) were independent predictive factors for pCR, OR=0.942 (95%CI: 0.918-0.967) and 0.961 (95%CI: 0.940-0.987), respectively. The area under ROC curve (AUC) for the constructed model was 0.886 (95%CI: 0.820-0.951). Decision curve showed that in the range of the threshold probability above 0.4, the predictive model presented increased net benefit as the threshold probability increased. Conclusions: The constructed predictive model for pCR is of potential clinical value, with an AUC>0.85. Meanwhile, decision curve analysis indicates the constructed predictive model has net benefit from 3 to 8 percent in the likely range of probability threshold from 80% to 90%.


Assuntos
Neoplasias da Mama , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Curva ROC , Resultado do Tratamento
14.
Phys Chem Chem Phys ; 19(30): 20137-20146, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28726864

RESUMO

New one-dimensional (1D) crystals, 1D quantum-dot arrays(1D QDAs), are proposed and constructed by an ordered arrangement of zigzag-edged triangular h-BN nanoflakes. Their geometrical stability is confirmed by the calculated binding energy, phonon dispersion and molecular dynamics simulation. These 1D QDAs demonstrate different quantum confinement effects on electronic and half-metallic properties due to different linking modes. For example, in the nonmagnetic state, different 1D QDAs are predicted to be semiconductors or metals remarkably depending on their linking manner, whereas in the ferromagnetic state, they are found to be all prominent half-metals but with greatly different gaps from ∼0.6 to 5.1 eV, reaching a difference almost as large as 10 times. In addition, the study on the electric-magnetic coupling effects suggests that the applied traversed electric field can significantly benefit the enhancement of 1D QDA half-metallicity by further enlarging the gap.

15.
Phys Chem Chem Phys ; 19(14): 9528-9536, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28345700

RESUMO

2D penta-graphene sheets were cut along typical crystallographic orientations in order to construct various penta-graphene nanoribbon (P-GNR) models, and their electronic structures and magnetic properties were systemically investigated. It was demonstrated that P-GNRs are very versatile with rich and unique electronic and magnetic properties. In particular, bipolar magnetic semiconducting features can be achieved in the ferromagnetic state for all magnetic P-GNRs, which makes P-GNRs valuable for developing next-generation information storage devices. More interestingly, studies on the electric-magnetic coupling revealed that an applied transverse electric field can transform a P-GNR from a magnetic semiconductor to a half-metal with a wide band gap of 0.88 eV, which can achieve complete spin filtering even at room temperature. Important advantages of magnetism over graphene nanoribbons are thus expected.

16.
Phys Chem Chem Phys ; 19(6): 4469-4477, 2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28120954

RESUMO

The structural and magneto-electronic properties and electric field-mediated effects for zigzag boron nitride nanoribbons (ZBNNRs) terminated with typical transition metal (TM) atoms (TM-ZBNNRs) are investigated systematically. Our work demonstrates that ZBNNRs form strong bonds with all studied termination atoms. The strong interactions and large orbital hybridizations of TM atoms to the ribbon make the magnetic anisotropy enhanced significantly, favorably to stabilize magnetism. The spin-split features for such hybridized structures can occur in most of the magnetic configurations, leading to a large magnetic moment. Higher spin polarization can be found in the ferromagnetic (FM) state. In particular, spin polarization exceeding 90% at the Fermi level can be achieved for Fe-ZBNNRs when an in-plane transverse electric field is applied. These results might be of interest from the prospects of both fundamental science and its potential applications.

17.
Zhonghua Yi Xue Za Zhi ; 97(20): 1576-1579, 2017 May 30.
Artigo em Zh | MEDLINE | ID: mdl-28592065

RESUMO

Objective: To explore the influence of adjuvant chemotherapy on the prognosis of hormone receptor negative breast cancer with residual lymph node disease(RLND)after neoadjuvant chemotherapy. Methods: A total of 110 hormone receptor negative breast cancer patients treated with 4-8 cycles of neoadjuvant chemotherapy were respectively analysed between 2002 and 2012. Residual lymph node disease was comfirmed by subsequent radical mastectomy. Then all these patients were classified into two groups: patients treated with adjuvant chemotherapy(group A) and patients untreated with adjuvant chemotherapy(group B). Results: All patients were female, the median age was 54.5 years old(IQR: 47-59 years). The median follow-up time was 61 months(IQR: 51-88 months). There were 82 patients (74.5%) in group A, and 28 patients (25.5%) in group B. The five-year disease-free survival (DFS) rate was 76.2% in group A and 57.6% in group B. The distant disease-free survival (DDFS) rate was 78.9% in group A and 60.4% in group B. Overall survival (OS) rate was 81.0% in group A and 60.0% in group B. Multivariate analysis showed that there were significant differences for DDFS rate (group A vs group B, P=0.033; hazard ratio [HR], 5.256; 95% confidence interval [95%CI], 1.14-24.17) and OS rates (group A vs group B, P=0.011; HR, 7.478; 95%CI, 1.58-35.30) between two groups. Conclusion: The patients who have hormone receptor negative breast cancer with RLND after neoadjuvant chemotherapy, may benefit from postoperative adjuvant chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Terapia Neoadjuvante , Neoplasias da Mama/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
18.
Zhonghua Wai Ke Za Zhi ; 55(2): 120-125, 2017 Feb 01.
Artigo em Zh | MEDLINE | ID: mdl-28162211

RESUMO

Objective: To explore the application value of pedicled thoracodorsal artery perforator flap in immediate partial breast reconstruction for breast cancer. Methods: This study is a prospective case series studies. Totally 128 cases of primary breast cancer patients who prepared to receive the breast-conserving surgery combine with immediate partial breast reconstruction of pedicled thoracodorsalartery perforator flap were enrolled in Breast Cancer Prevention and Treatment Center of Peking University Cancer Hospital from June 2013 to March 2016. Finally, the operations had been completed successfully in 33 eligible cases. All patients were female with a median age of 40 years (ranging from 22 to 52 years). The perforator vessel location, the donor area design, the post-operative complications, the influence of radiation and chemotherapy had been evaluated. Results: The average diameter of thoracic dorsal artery perforators measured by Doppler ultrasound before the operation was (1.5±0.4) mm (ranging from 0.6 to 2.7 mm). The average size of flaps was 15 cm×6 cm. The average time of operations was (271±72) minutes (ranging from 120 to 245 minutes). Drainage tube removed on (4.7±2.1) days after operation (ranging from 3 to 12 days). All patients received follow-up, and there was no local recurrence and distant metastasis during a median follow-up of 17(12) months (M(Q(R))) (ranging from 5 to 38 months). All TDAP flaps were survival, the wound complication rates was 6% (2/33). Conclusions: The breast reconstruction of pedicled thoracodorsal artery perforator flap is a good choice of repairing local breast defect of breast conserving surgery.Its advantages are no-influence of latissimus dorsi function and little complications in donor area.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia Segmentar , Retalho Perfurante , Adulto , Artérias , Feminino , Humanos , Mamoplastia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Estudos Prospectivos , Retalhos Cirúrgicos , Adulto Jovem
19.
Zhonghua Zhong Liu Za Zhi ; 38(3): 185-9, 2016 Mar 23.
Artigo em Zh | MEDLINE | ID: mdl-26988823

RESUMO

OBJECTIVE: To explore the relationship of clinicopathological features and response to neoadjuvant chemotherapy in women with BRCA1 and BRCA2 mutation-negative familial breast cancer. METHODS: A total of 6 200 women with breast cancer were treated at our hospital from October 2003 to December 2012. All subjects underwent genetic testing for BRCA1 and BRCA2 genes. Patients with BRCA1 and BRCA2 mutations were excluded. This cohort of 5 842 patients with BRCA1 and BRCA2 mutation-negative breast cancer was classified as two groups: familial breast cancer patients (n=480) and sporadic breast cancer patients (n=5 362). The clinicalpathological data and response to neoadjuvant chemotherapy of the 480 patients with BRCA1 and BRCA2 mutation-negative familial breast cancer and the 5 362 patients with BRCA1 and BRCA2 mutation-negative sporadic breast cancer were compared retrospectively. Then the influencing factors of response to neoadjuvant chemotherapy were analyzed. RESULTS: Among the BRCA1 and BRCA2 mutation-negative breast cancer patients, 4.4% of the patients were diagnosed before 30 years of age in the familial breast cancer group, significantly higher than that of 2.6% in the sporadic breast cancer group(P=0.020). 5.0% of the patients in the familial breast cancer group had bilateral breast cancer, significantly higher than that of 2.7% in the sporadic breast cancer group (P=0.004). Compared with BRCA1 and BRCA2 mutation-negative sporadic breast cancer patients, the relative risk of early-onset breast cancer (≤ 30 years) and bilateral breast cancer were 1.73 and 1.91, respectively, significantly higher than that in the BRCA1 and BRCA2 mutation-negative familial breast cancer cases (P=0.020 and P=0.004). 2 964 patients in this cohort of 5 842 case sreceived neoadjuvant chemotherapy.The pathologic complete response (pCR) rate was significantly higher in the BRCA1 and BRCA2 mutation-negative familial breast cancer group than in the BRCA1 and BRCA2 mutation-negative sporadic breast cancer group (21.7% vs. 14.0%, P=0.001). Independent factors associated with pCR in BRCA1 and BRCA2 mutation-negative breast cancer patients were tumor size less than 2 cm (P=0.012), histologic grade Ⅲ (P<0.001), triple-negative breast cancers (P<0.001), and BRCA1 and BRCA2 mutation-negative familial breast cancer(P=0.001). CONCLUSIONS: Compared with BRCA1 and BRCA2 mutation-negative sporadic breast cancer, BRCA1 and BRCA2 mutation-negative familial breast cancer is more likely diagnosed before the age of 30 years and has a higher risk to develop bilateral breast cancer. BRCA1 and BRCA2 mutation-negative familial breast cancers are more likely to respond to neoadjuvant chemotherapy than BRCA1 and BRCA2 mutation-negative sporadic breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Adulto , Fatores Etários , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Detecção Precoce de Câncer , Feminino , Predisposição Genética para Doença , Humanos , Terapia Neoadjuvante , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas
20.
Zhonghua Yi Xue Za Zhi ; 96(32): 2578-82, 2016 Aug 23.
Artigo em Zh | MEDLINE | ID: mdl-27596555

RESUMO

OBJECTIVE: To study the impact of anti-HER2 therapy and response of primary tumor on distant disease free survival (DDFS) of the patients with HER2-positive breast cancer. METHODS: The clinical data of the patients with HER2-positive breast cancer treated with neoadjuvant systemic therapy were analyzed retrospectively. RESULTS: Patients treated with preoperative anti-HER2 therapy and chemotherapy had a significant improved pathological complete response (pCR) rate (48.4%) compared with those treated with preoperative chemotherapy (17.2%) (P=0.000). The median follow-up period was 62(6-160) months. The 5-year DDFS in patients with anti-HER2 therapy and patients without anti-HER2 therapy was 93.5% and 83.3% respectively (P=0.006). The 5-year DDFS in patients achieving a pCR and patients not achieving a pCR was 94.7% and 82.6% respectively(P=0.001). Among patients achieving a pCR, anti-HER2 therapy did not improve DDFS significantly (P=0.960). Benefits of anti-HER2 therapy in DDFS among patients without a pCR achieved statistical significance (P=0.028). CONCLUSIONS: Combination of neoadjuvant anti-HER2 therapy and chemotherapy resulted in a higher pCR rate in HER2-overexpressing primary breast cancer. Patients treated with neoadjuvant systemic therapy who achieved a pCR have excellent outcome regardless of whether they received anti-HER2 therapy.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Antineoplásicos , Intervalo Livre de Doença , Humanos , Receptor ErbB-2 , Estudos Retrospectivos , Trastuzumab
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