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1.
Zhonghua Er Ke Za Zhi ; 62(7): 636-642, 2024 Jul 02.
Artigo em Chinês | MEDLINE | ID: mdl-38955681

RESUMO

Objective: To investigate the effects of modified endoscopic retrograde appendicitis therapy (mERAT) on the treatment of children with different severities of acute appendicitis. Methods: This study was a case-control study. A total of 586 children with acute appendicitis, who were admitted to the Pediatric Department of Second Affiliated Hospital of Air Force Medical University between January 2019 and November 2023, were selected as the research subjects. According to the severity of the disease, the patients were divided into simple appendicitis group, suppurative appendicitis group and perforated appendicitis group. The baseline data, hospitalization treatment and costs, outcomes, and recurrence in each group were analyzed, and the difference in the effectiveness of mERAT between the groups were compared by Kruskal-Wallis H test and χ2 test. Results: Among 586 children, there were 338 males and 248 females. The age at onset was 7.0 (4.6, 9.4) years. There were 475 cases of simple appendicitis, 78 cases of suppurative appendicitis, and 33 cases of perforated appendicitis. There were no significant differences in age and gender among the three groups (F=0.59, χ2=3.31, both P>0.05). However, there were statistically significant differences in body temperature, white blood cell counts, neutrophil percentage, lymphocyte percentage, nausea or vomiting, right lower abdominal pain, umbilical pain, right lower abdominal tenderness, and right lower abdominal rebound pain (H=7.56, 161.52, 169.11, and 169.61, χ2=12.05, 13.82, 12.05, 7.74, 20.35, and 94.61, all P<0.05). Also, the treatment time, postoperative hospital stay, total hospital stay, and cost showed statistically significant differences (H=4.70, 33.66, 34.99, 30.37, all P<0.05). There was no significant difference in the initial treatment success rate (98.1% (466/475) vs. 98.7% (77/78) vs. 90.9% (30/33), P=0.057). During the 30 (23, 36) months of follow-up, the recurrence rate was 7.9% (35/433) in the simple appendicitis group, 20.8% (15/72) in the suppurative appendicitis group, and 30.0% (9/30) in the perforated appendicitis group, with a statistically significant difference (χ2=23.56, P<0.001). Among the children with recurrent appendicitis, 15 cases still chose mERAT, of them 11 cases (31.2%) had simple appendicitis, 2 cases (2/15) had suppurative appendicitis, and 2 cases (2/9) had perforated appendicitis.The latest time to recurrence in the 3 groups was 32, 35 and 10 months, respectively. Conclusion: Treatment with mERAT has a good effect in pediatric simple appendicitis, but has a higher recurrence rate despite a better initial treatment success rate in suppurative appendicitis and perforated appendicitis.


Assuntos
Apendicite , Humanos , Apendicite/cirurgia , Apendicite/terapia , Masculino , Feminino , Criança , Estudos de Casos e Controles , Resultado do Tratamento , Pré-Escolar , Apendicectomia/métodos , Doença Aguda , Endoscopia/métodos , Índice de Gravidade de Doença , Recidiva , Hospitalização , Tempo de Internação
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(9): 1497-1503, 2023 Sep 06.
Artigo em Chinês | MEDLINE | ID: mdl-37743314

RESUMO

It is well known that vitamin D is engaged in calcium and phosphorus metabolism. However, vitamin D also plays an important role in other aspects over the past decades, such as immune response. Vitamin D has thus aroused the interest of the scientific community, especially the field of dermatology. The major source of vitamin D comes from the exposure of the skin to ultraviolet B. In turn, vitamin D regulates the proliferation and differentiation of keratinocytes, prevents opportunistic infection, and regulates the inflammatory response and immune response of the skin. Acne, psoriasis, atopic dermatitis, and other inflammatory skin diseases have been found to have a certain relationship with vitamin D. This article review the correlation between vitamin D and inflammatory skin diseases.

3.
Ann Oncol ; 34(6): 520-530, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36863483

RESUMO

BACKGROUND: The intestinal microbiome has been associated with response to immune checkpoint inhibitors (ICIs) in humans and causally implicated in ICI responsiveness in animal models. Two recent human trials demonstrated that fecal microbiota transplant (FMT) from ICI responders can rescue ICI responses in refractory melanoma, but FMT has specific limitations to scaled use. PATIENTS AND METHODS: We conducted an early-phase clinical trial of a cultivated, orally delivered 30-species microbial consortium (Microbial Ecosystem Therapeutic 4, MET4) designed for co-administration with ICIs as an alternative to FMT and assessed safety, tolerability and ecological responses in patients with advanced solid tumors. RESULTS: The trial achieved its primary safety and tolerability outcomes. There were no statistically significant differences in the primary ecological outcomes; however, differences in MET4 species relative abundance were evident after randomization that varied by patient and species. Increases in the relative abundance of several MET4 taxa, including Enterococcus and Bifidobacterium, taxa previously associated with ICI responsiveness, were observed and MET4 engraftment was associated with decreases in plasma and stool primary bile acids. CONCLUSIONS: This trial is the first report of the use of a microbial consortium as an alternative to FMT in advanced cancer patients receiving ICI and the results justify the further development of microbial consortia as a therapeutic co-intervention for ICI treatment in cancer.


Assuntos
Inibidores de Checkpoint Imunológico , Melanoma , Animais , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Ecossistema , Resultado do Tratamento , Transplante de Microbiota Fecal/métodos , Melanoma/tratamento farmacológico
4.
J Colloid Interface Sci ; 640: 52-60, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36841171

RESUMO

Although transition metal selenides are considered to be extremely promising anode materials for lithium-ion batteries (LIBs), severe volume changes and low electronic conductivity are their huge and unavoidable challenges. To solve these problems, CoSe nanoparticles in-situ grown on the inner surface of every macropore of 3D honeycomb C is successfully synthesized by three simple steps: dense assembling of polystyrene spheres, calcination and gaseous selenylation. The sizes of CoSe and honeycomb pores are 10-15 nm and 190 nm, respectively. The content of CoSe is 72 wt%. This unique architecture guarantees high electrochemical activity, rapid reaction kinetics and excellent structural stability of CoSe, as identified by cycling and rate performance measurements, various electrochemical kinetics analyses and ex-situ characterization of the cycled electrode material. As a result, the CoSe@honeycomb C anode exhibits extraordinary cycling performance (823.5 mAh g-1 after 200 cycles at 0.5 A g-1, 610.1 mAh g-1 after 250 cycles at 2 A g-1, 247 mAh g-1 after 1500 cycles at 5 A g-1) and exceptional rate capability (261.9 mAh g-1 at 10 A g-1, 1491.4 mAh g-1 at 0.1 A g-1), demonstrating that it is a potential anode material for high-performance LIBs.

5.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 40(10): 771-775, 2022 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-36348560

RESUMO

Objective: To compare the efficacy of high-flow nasal cannula oxygen therapy (HFNC) and non-rebreather face mask (NRFM) in the treatment of mild acute carbon monoxide poisoning (ACOP) in reducing carboxyhemoglobin (COHb) , and to explore the feasibility of HFNC in the treatment of ACOP. Methods: Patients with mild ACOP with COHb >10% who were admitted to the emergency department of Northern Jiangsu People's Hospital from January 2015 to December 2020 were analyzed, and those with altered consciousness, mechanical ventilation and those requiring hyperbaric oxygen therapy were excluded. The patients were divided into HFNC group and NRFM group according to the oxygen therapy used in the emergency department. The COHb decline value and COHb half-life in the two groups were observed. Results: Seventy-one patients were enrolled, including 39 in the NRFM group and 32 in the HFNC group. The baseline COHb in the HFNC group was 24.8%±8.3%, and that in the NRFM group was 22.5%±7.1%, with no significant difference between the two groups (t=1.27, P=0.094) . At 60 min, 90 min and 120 min of treatment, COHb in both groups decreased, but the COHb in HFNC group was lower than that in NRFM group at the same time point (P<0.05) . After 1 h of treatment, the COHb decrease in the HFNC group (16.9%±4.5%) was significantly higher than that in the NRFM group (10.1%±7.8%) (t=4.32, P=0.013) . The mean half-life of COHb in the HFNC group (39.3 min) was significantly lower than that in the NRFM group (61.4 min) (t=4.69, P=0.034) . Conclusion: HFNC treatment of mild ACOP can rapidly reduce blood COHb level, it is a potential oxygen therapy method for clinical treatment of ACOP.


Assuntos
Intoxicação por Monóxido de Carbono , Insuficiência Respiratória , Humanos , Intoxicação por Monóxido de Carbono/terapia , Cânula , Respiração Artificial , Máscaras , Oxigenoterapia/métodos , Carboxihemoglobina , Oxigênio/uso terapêutico , Insuficiência Respiratória/terapia
6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(10): 1079-1083, 2022 Oct 09.
Artigo em Chinês | MEDLINE | ID: mdl-36266084

RESUMO

The use of dynamic navigation technology in edentulous jaw implant restoration can solve many problems associated with traditional edentulous jaw implant restoration. The benefits of dynamic navigation include fine positioning guidance, restoration-guided surgery, good aesthetic results, and the possibility of simultaneous conceptual design and real-time implant guidance, as well as the transition from "blind" to "direct" vision during the implantation. It can guide clinicians and adjust the plan in real time, improve the efficiency of communication between the clinician, technician, and patient throughout the process and so on. The workflow, current clinical application and challenges, accuracy analysis, and limitations of the dynamic navigation technology in the edentulous jaw are discussed in this paper, as well as an outlook on its future development, with the goal of contributing to the clinical development of dynamic navigation-guided implantology in the edentulous jaw.


Assuntos
Implantes Dentários , Arcada Edêntula , Cirurgia Assistida por Computador , Humanos , Implantação Dentária Endóssea/métodos , Cirurgia Assistida por Computador/métodos , Estética Dentária , Arcada Edêntula/cirurgia , Tecnologia
7.
Zhonghua Er Ke Za Zhi ; 60(7): 647-654, 2022 Jul 02.
Artigo em Chinês | MEDLINE | ID: mdl-35768351

RESUMO

Objective: To investigate the epidemiology, characteristics and risk factors of functional constipation (FC) in children aged 0-4 years in Xi'an. Methods: From October, 2020 to June, 2021, a prevalence survey was conducted among 2 615 children aged 0-4 years in Xi'an by group sampling. The related factors of FC were investigated by questionnaire designed based on Rome Ⅳ diagnostic criteria.The children were divided into FC group and non-FC group. The prevalence, symptoms and signs of FC were analyzed, and its risk factors were analyzed by multivariate Logistic regression. Results: A total of 2 985 valid questionnaires were handed out, and 2 711 (90.8%) were received back. A total of 2 615 questionnaires were valid, with an effective rate of 96.5%. There were 1 338 males (51.2%) and 1 277 females (48.8%). There were 260 cases in FC group and 2 355 cases in non-FC group. The prevalence of FC in children aged 0-4 years in Xi 'an was 10.6%.There were significant differences in FC prevalence among children of different ages and sex (χ2=14.58,4.39, both P<0.05), but not in urban or rural residence (χ2=3.29, P=0.070). The main symptoms of FC group in the last month were large-diameter feces (73.5%, 191/260), painful defecation or dry and hard defecation (65.8%, 171/260). In the last month, FC group had higher incidences of the Bristol type 1, 2 and 3 stool, fecal retention, prolonged defecation, abdominal pain and incomplete defecation compared with non-FC group, with statistical significance (all P<0.05). Parental history of childhood constipation (OR=2.13, 95%CI 1.55-2.92), fever in the last month (OR=1.86, 95%CI 1.32-2.63), history of constipation (OR=3.24, 95%CI 2.46-4.26) and taking probiotics in the last month (OR=1.45, 95%CI 1.11-1.91) were risk factors of FC in children aged 0-4 years. Stratified with age, the results showed that complementary feeding earlier than 5 months of age or later than 6 months of age (OR=2.42, 95%CI 1.13-5.20), dry stools during the complementary feeding (OR=11.27, 95%CI 5.15-24.66), history of constipation (OR=2.29, 95%CI 1.23-4.29) and taking probiotics in the last month (OR=1.88, 95%CI 1.10-3.23) were risk factors of FC in children aged 0-<1 year, and breastfeeding (OR=0.53, 95%CI 0.29-0.94) was a protective factor of FC in children aged 0-<1 year. Family members' recent constipation history (OR=2.02, 95%CI 1.06-3.85) and past history of constipation (OR=3.06, 95%CI 1.74-5.38) were FC risk factors for children aged 1-<2 years. Parental history of childhood constipation (OR=3.12, 95%CI 2.00-4.85), frequency of eating vegetables less than 3 times per week (OR=3.28, 95%CI 2.00-5.38), history of constipation (OR=3.66, 95%CI 2.42-5.53) and taking antibiotics in the last month (OR=1.65, 95%CI 1.06-2.55) were risk factors for FC in children aged 2-4 years. Conclusions: FC in children aged 0-4 years in Xi'an is mainly manifested with large-diameter feces and painful defecation or dry and hard defecation in the last month. It is associated with a variety of risk factors, which are different in different age groups.


Assuntos
Constipação Intestinal , Defecação , Criança , Constipação Intestinal/diagnóstico , Constipação Intestinal/epidemiologia , Fezes , Feminino , Humanos , Lactente , Masculino , Fatores de Risco , Inquéritos e Questionários
8.
Zhonghua Yi Xue Za Zhi ; 102(19): 1417-1422, 2022 May 24.
Artigo em Chinês | MEDLINE | ID: mdl-35599405

RESUMO

Objective: To explore the changes of cerebral blood perfusion in patients with unilateral sudden sensorineural hearing loss (SSNHL) by using the three-dimensional pseudo-continuous arterial spin labeling (3D pCASL) technique. Methods: The clinical characteristics and ASL data of the 32 patients with unilateral SSNHL were retrospectively collected from November 2020 to June 2021 in Beijing Fuxing Hospital of Capital Medical University, among them, there were 7 males and 25 females, aged from 17 to 73 (44.9±14.4) years. According to the location of SSNHL, they were divided into the left SSNHL (L-SSNHL) group (18 cases) and the right SSNHL (R-SSNHL) group (14 cases). A total of 34 healthy volunteers, which including 14 males and 20 females, aged from 24 to 68 (46.2±14.4) years were enrolled from the local community. The parameter of cerebral blood flow (CBF) of each brain area was obtained using the CereFlow software. The Brainnetome Atlas software package based on MATLAB was used for visualization. The independent-samples t test was conducted to compare the difference of cerebral blood perfusion between the unilateral SSNHL group and healthy control (HC) group. Pearson correlation analysis was used to evaluate the correlation between changes in cerebral blood perfusion and clinical scale scores. Results: The CBF of left orbital gyrus part 5, left inferior temporal gyrus part 7, right orbital gyrus part 5, right inferior temporal gyrus part 1, right inferior temporal gyrus part 7, and right parahippocampal gyrus part 3 of the L-SSNHL group were higher than that in the HC group[(49.1±8.8) vs (31.6±10.9)ml·100g-1·min-1;(42.8±14.3) vs (27.1±13.6)ml·100g-1·min-1;(51.8±9.4) vs (27.2±11.2)ml·100g-1·min-1;(38.8±5.7) vs (28.0±9.2)ml·100g-1·min-1;(38.4±13.8) vs (23.6±10.3)ml·100g-1·min-1;(42.4±9.4) vs (30.1±12.6)ml·100g-1·min-1; all P<0.05]. The CBF of left superior frontal gyrus part 7 and left middle frontal gyrus part 3 of the L-SSNHL group were lower than that in the HC group[(48.2±7.9) vs (59.3±13.7)ml·100g-1·min-1;(46.4±10.3) vs (59.3±16.9)ml·100g-1·min-1;all P<0.05]. The CBF of left orbital gyrus part 5, right orbital gyrus part 5, right inferior temporal gyrus part 1, and right inferior temporal gyrus part 7 of the R-SSNHL group were higher than that in the HC group[(50.6±7.0) vs (31.6±10.9)ml·100g-1·min-1;(50.9±8.8) vs (27.2±11.2)ml·100 g-1·min-1;(38.0±7.2) vs (28.0±9.2)ml·100g-1·min-1;(35.7±8.5) vs (23.6±10.3)ml·100g-1·min-1;all P<0.05]; the CBF of right insular part 4 was lower than that in the HC group [(44.2±6.1) vs (54.4±11.3) ml·100 g-1·min-1, P=0.018]. In the L-SSNHL group, the CBF of left superior frontal gyrus part 7 and right orbital gyrus part 5 were negatively correlated with the VAS score(r=-0.83, -0.81, all P<0.05), and the CBF of right orbital gyrus part 5 was negatively correlated with the THI score(r=-0.75, P=0.013). There was no statistically significant correlation between the remaining differences in brain regions and clinical scale scores(all P>0.05). Conclusion: Changes in cerebral blood perfusion in multiple brain regions were found in patients with unilateral SSNHL by using the 3D pCASL technique.


Assuntos
Perda Auditiva Neurossensorial , Imageamento por Ressonância Magnética , Encéfalo , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Perfusão , Estudos Retrospectivos , Marcadores de Spin
11.
Eur Rev Med Pharmacol Sci ; 23(22): 10161-10168, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31799688

RESUMO

OBJECTIVE: The aim of this study was to explore the promoting effect of rosuvastatin on the osteogenic differentiation of mesenchymal stem cells in the rat model of osteoporosis through the Wnt/ß-catenin signal. MATERIALS AND METHODS: A total of 30 rats were purchased from the Animal Research Center of Shanxi Medical University. All rats were randomly allocated into three groups, including: group A (control group, n=10), group B (ovariectomized group, n=10), and group C (rosuvastatin gavage group, n=10). The bone metabolism indexes, bone mineral density (BMD) and the Wnt/ß-catenin signaling pathway-related proteins in blood samples of rats in each group were measured, respectively. Furthermore, the bone marrow mesenchymal stem cells of rats were used for alkaline phosphatase (ALP) staining. All data were analyzed using the Statistical Product and Service Solutions (SPSS) 22.0 software (IBM Corp., Armonk, NY, USA). RESULTS: The rats firstly received 9 consecutive weeks of feeding with drug intervention. The imaging results revealed that trabecular thickness in group A was significantly higher than that of group B and group C, showing statistically significant differences (p<0.05). After 9 consecutive weeks of feeding with drug intervention, BMD of the femurs of rats in group A and group C was significantly higher than that of group B, showing statistically significant differences (p<0.05). However, there was no significant difference in BMD between group A and group C (p>0.05). The level of calcium representing bone absorption level in serum of rats in group B was remarkably higher than that of group A, and the difference was statistically significant (p<0.05). However, the level of ALP representing bone absorption level in the serum of rats in group B was significantly lower than that of group A (p<0.05). No significant differences were found in the levels of calcium and ALP that represented bone absorption level between group C and group A (p>0.05). Meanwhile. the levels of phosphorus in the three groups were similar, showing no statistically significant difference (p>0.05). Moreover, the expression of ALP-positive cells in the rats of group A and group C was markedly higher than that of group B (p<0.05). After drug intervention through feeding for 9 consecutive weeks, no evident difference was found in the relative expression of Wnt/ß-catenin signaling pathway-related protein glycogen synthase kinase-3ß (GSK-3ß) among the three groups. The relative expression of the protein phosphorylated GSK-3ß (p-GSK-3ß) in group C was significantly lower than that of group B (p<0.05). Furthermore, the relative protein expressions of ß-catenin and cyclin D1 in group C were significantly higher than those in group B (p<0.05). CONCLUSIONS: Rosuvastatin can improve bone metabolism in osteoporosis rats and increasing BMD of bone tissues in rats with osteoporosis. Besides, the Wnt/ß-catenin signaling pathway plays a crucial role in the regulation of the stem cell self-renewal and bone genesis.


Assuntos
Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Rosuvastatina Cálcica/administração & dosagem , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoporose/etiologia , Osteoporose/metabolismo , Ovariectomia/efeitos adversos , Distribuição Aleatória , Ratos , Rosuvastatina Cálcica/farmacologia , Resultado do Tratamento
12.
Eur Rev Med Pharmacol Sci ; 23(2): 732-739, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30720181

RESUMO

OBJECTIVE: Cerebrovascular disease is a disease which has the highest mortality in China. Angiogenesis in the ischemic region after cerebral infarction is closely related to its prognosis. Recent studies found that microRNAs (miRNAs) are involved in the regulation of neovascularization. MicroRNA-153 (MiR-153) has protective effects on the ischemic injury, but its relationship with the Sonic Hedgehog (Shh) signaling pathway is still unclear. This work aimed to investigate the role of miR-153 in angiogenesis of middle cerebral artery occlusion (MCAO) rats through the Shh signaling pathway. MATERIALS AND METHODS: The rat cerebral ischemic injury (MCAO) model was established by thread embolism and treated by Agomir-153 and 5-EI. MiR-153 expression was detected using Real Time-Polymerase Chain Reaction (RT-PCR). The neurological function was assessed. The infarct area of the brain and the capillary density were determined using 2,3,5-triphenyl tetrazolium chloride (TTC) method. The Shh signaling pathway and angiogenesis-related factors were tested by Western blot assay. RESULTS: Agomir-153 or Agomir-153 combined with 5-EI significantly increased miR-153 expression, reduced the infarct area, and promoted the generation of cerebral capillaries in the MCAO model. 5-EI partially blocked the protective effects of Agomir-153 and angiogenesis. The up-regulation of miR-153 markedly inhibited patched (PTC) expression and activated the Shh signaling pathway. CONCLUSIONS: The up-regulation of miR-153 rats activated the Shh signaling pathway to promote angiogenesis and improve prognosis through lipid-coated Patch (PTC) in MCAO. MiR-153 was considered to be a new therapeutic target for promoting angiogenesis after MCAO.


Assuntos
Proteínas Hedgehog/metabolismo , Infarto da Artéria Cerebral Média/patologia , MicroRNAs/metabolismo , Neovascularização Fisiológica/genética , Transdução de Sinais/genética , Animais , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Proteínas Hedgehog/antagonistas & inibidores , Humanos , Receptor Patched-1/genética , Ratos , Transdução de Sinais/efeitos dos fármacos
13.
Nanoscale ; 10(38): 18282-18290, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30246846

RESUMO

An efficient route is proposed to actively manipulate directional scattering based on magneto-optical (MO) effects and multipolar interferences with a coated MO cylinder. We demonstrate that the presence of an external magnetic field B contributes to breaking the degeneracy of multipoles and making them rotate. The rotated modes further interfere with each other, thus reshaping scattering profiles and introducing novel directional optical switching (OS) phenomena. As a result, we show that forward scattering (FS) and backward scattering (BS) can be flexibly altered by turning on or off the B for both s-polarization and p-polarization, and optical switching exhibits broadband performance as well. More specifically, the proposed nanostructure also operates robust and reliable functionalities when considering realistic MO materials with optical loss and dispersion; therefore, they are ideal candidates to develop reconfigurable, tunable and versatile optical devices.

15.
Opt Express ; 26(6): 7235-7252, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29609409

RESUMO

We have achieved efficient polarization manipulations based on dipolar interferences and lattice couplings in one-dimensional cylindrical metalattices. First, we employ the scattering asymmetry factor g to quantify the directional scattering ability and find the maximum |g|max=1/2 for a cylinder with effective excitations of electric and magnetic dipoles simultaneously. Further, the strong negative-g (gp = -0.38) for p-polarization and positive-g (gs = 0.68) for s-polarization are obtained within a narrow visible band using c-Si with experimental data. Inspired by the polarization-dependent phenomena, we design a metalattice-based linear polarizer considering lattice effects with an optimal particle arrangement. The metalattice performs near-perfect reflection for p-polarized waves but with zero reflection for s-polarized waves with large extinction ratios for transmission (17 dB) and reflection (24 dB). The perfect functionalities can be attributed to the near-field lattice couplings with dipolar interferences. And, we reveal that the polarization-dependent scattering coefficients, which are sensitive to the lattice period, can be largely tuned owing to lattice effects, therefore contributing to modifying far-field scattering patterns. More specifically, the proposed linear polarizers also show robust and reliable functionalities when considering lattice imperfections, the effects of system sizes, oblique incident angles, and the tunbility for different working wavelengths. The present study paves a way to stimulate many advanced practical implements based on multipolar interferences and lattice couplings.

16.
Opt Express ; 25(16): 18760-18773, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-29041070

RESUMO

Engineering light-matter interaction using cold atomic arrays is one of the central topics in modern optics. Here we have demonstrated the capability of two-dimensional asymmetric cold atomic arrays as microscopic metasurfaces for controlling polarization states of light. The designed linear polarizer can lead to an extinction ratio over 20dB as well as a high transmittance over 0.8 for the permitted polarization at zero detuning. For detuned driving light, changing lattice constants can also achieve high performance linear polarizers. We have also accomplished a circular polarizer by manipulating the phases of transmitted light. A theoretical analysis based on Bloch theorem shows the underlying mechanism for this performance is actually attributed to cooperative effects in periodic lattices. Finally, we discuss in detail the effects of system size, lattice imperfection and nonzero driving light linewidth in practical implementation. The present study paves a way to design extremely miniaturized metasurfaces using cold atoms and other two-level systems, showing great potential in quantum information and quantum metrology sciences as well as the fundamental physics of light-matter interaction.

17.
Opt Lett ; 42(10): 1879-1882, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28504749

RESUMO

In this Letter, we propose a method to design ultrabroadband near-perfect absorbers, consisting of a periodic dielectric-metal multilayer. In the method, the Bloch theorem and optical topological transition (OTT) of iso-frequency surfaces are employed to manipulate the start and end of the near-perfect spectral absorption band, respectively. Moreover, we design and fabricate an ultrabroadband near-perfect absorber utilizing the proposed method. The average absorption of the designed absorber is ∼95% in the focused visible and near-infrared range (0.4-2 µm). This omnidirectional and polarization-independent near-perfect absorber is promising for solar energy harvesting, emissivity control, and thermal imaging.

18.
Zhonghua Er Ke Za Zhi ; 55(3): 200-204, 2017 Mar 02.
Artigo em Chinês | MEDLINE | ID: mdl-28273703

RESUMO

Objective: To explore the composition of the gastrointestinal bacterial flora of mouse embryos and the placenta tissue bacterial flora. Method: Twenty-four specimens were collected from pregnant Kunming mouse including 8 mice of early embryonic (12-13 days) gastrointestinal tissues, 8 cases of late embryonic (19-20 days)gastrointestinal tissues, 8 of late pregnancy placental tissues.The 24 samples were extracted by DNeasy Blood & Tissue kit for high-throughput DNA sequencing. Result: The level of Proteobacteria, Bacteroidetes, Actino-bacteria and Firmicutes were predominantin all specimens.The relative content of predominant bacterial phyla in each group: Proteobacteria (95.00%, 88.14%, 87.26%), Bacteroidetes(1.71%, 2.15%, 2.63%), Actino-Bacteria(1.16%, 4.10%, 3.38%), Firmicutes(0.75%, 2.62%, 2.01%). At the level of family, there were nine predominant bacterial families in which Enterobacteriaeae, Shewanel laceae and Moraxellaceae were dominant.The relative content of dominant bacterial family in eachgroup: Enterobacteriaeae (46.99%, 44.34%, 41.08%), Shewanellaceae (21.99%, 21.10%, 19.05%), Moraxellaceae(9.18%, 7.09%, 5.64%). From the species of flora, the flora from fetal gastrointestinal in early pregnancy and late pregnancy (65.44% and 62.73%) were the same as that from placenta tissue in the late pregnancy.From the abundance of bacteria, at the level of family, the same content of bacteria in three groups accounted for 78.16%, 72.53% and 65.78% respectively. Conclusion: It was proved that the gastrointestinal bacterial flora of mouse embryos and the placenta tissue bacterial flora were colonized. At the same time the bacteria are classified.


Assuntos
Bactérias , DNA Bacteriano , Placenta/microbiologia , Animais , Bacteroidetes , Embrião de Mamíferos , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Camundongos , Gravidez , RNA Ribossômico 16S
19.
Artigo em Chinês | MEDLINE | ID: mdl-29771043

RESUMO

Objective:The aim of this study is to investigate the inhibitory effect and mechanism of tanshinone ⅡA combined with cisplatin on tumor Fadu cells in pharyngeal squamous cell carcinoma. Method:Cytotoxicity was determined by CCK8 assay. Flow cytometry was used to detect apoptosis and cell cycle distribution. Western blotting was used to assess the protein expression of related signaling proteins. Result:Compared with the two single drug groups treated with Tan ⅡA and DDP respectively, the combination group showed significantly higher anti-proliferative rate (P<0.01), arrested cell cycle at S phase, and resulted in observably higher apoptotic cell fractions in human hypopharyngeal squamous cell carcinomas Fadu cells; Western blotting showed that the protein expression of cleaved caspase 3 and cleaved PARP increased ,while survivin significantly decreased in the cells treated with the combination of tanshinone ⅡA and cisplatin. Conclusion:Tanshinone ⅡA potentiates the efficacy of Cisplatin in Fadu cells, which may be attributed to the downregulation of survivin protein expression.


Assuntos
Abietanos/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Proteínas Inibidoras de Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Humanos , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Hipofaríngeas/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Survivina
20.
Phys Chem Chem Phys ; 18(39): 27078-27082, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27711679

RESUMO

A one dimensional nanostructure array has been considered as a successful charge transport material for perovskite solar cells (PSCs), because of its large internal surface area, superior charge collection efficiency and fast charge transport. Herein we demonstrate a ZnO nanorod (NR) array as the electron collector in a hole-conductor-free PSC with a carbon counter electrode (CE). A relatively low initial power conversion efficiency (PCE) of 5.6% was achieved using a 1 µm long ZnO NR array as an electron collector. However, by introduction of a thin TiO2 coating layer on the surface of ZnO via TiCl4 treatment, the PCE of the cell has been improved to the highest value of 8.24%. It is revealed that the performance enhancement of the ZnO/TiO2 NR based PSCs is largely attributed to the larger surface area, reduced electron combination, and superior electron transport properties.

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