Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
BMC Womens Health ; 24(1): 7, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166995

RESUMEN

BACKGROUND: In this study, the prognostic and reproductive outcomes of women who underwent excision of uterine myomas and were sutured using different techniques while undergoing a cesarean section were investigated. METHODS: A total of 299 females who underwent cesarean section between January 2015 and June 2022 due to a scarred uterus were enrolled in this study. These participants were segregated into two categories: the experimental group (comprising 155 cases) in which uterine myoma (single lesion) was excised during the cesarean procedure, and the control group (consisting of 144 cases) in which only the cesarean section was conducted. A comparison between the two groups was carried out based on the following parameters: volume of intraoperative bleeding (mL), additional measures taken for intraoperative hemostasis (n, %), percentage (%) of patients experiencing postoperative fever, duration required for the passage of gas (hours [h]), length of hospital stay (days [d]), weight of newborns (kg) and their Apgar scores, and the reproductive outcomes of the experimental group assessed two years after the surgical procedure. RESULTS: In the experimental group, the amount of bleeding during surgery, occurrence of postoperative fever among women, time taken for patients to resume passing gas, and length of hospital stay were 540.65 ± 269.12 mL, 9.03%, 15.99 ± 4.68 h, and 5.08 ± 1.18 days, respectively. In contrast, the control group had values of 409.03 ± 93.24 mL, 2.77%, 16.24 ± 4.92, and 4.47 ± 0.70 days, respectively (P < 0.05). No notable increase was observed in the need for additional intraoperative hemostasis measures, and there was no significant difference in the time it took for patients to pass gas after the surgery. All newborns had positive health status. In the experimental group, 25 patients underwent subsequent pregnancies, and 15 of them successfully reached full-term deliveries, all of which had positive outcomes. CONCLUSION: Combining myomectomy with various suture methods during cesarean delivery did not cause excessive bleeding and resulted in healthy newborns. This approach offers the advantage of avoiding additional surgeries under anesthesia and can be considered a viable option. Subsequent pregnancies after myomectomy were considered high-risk.


Asunto(s)
Leiomioma , Mioma , Miomectomía Uterina , Neoplasias Uterinas , Femenino , Humanos , Recién Nacido , Embarazo , Cesárea , Leiomioma/cirugía , Leiomioma/patología , Pronóstico , Estudios Retrospectivos , Miomectomía Uterina/métodos , Neoplasias Uterinas/cirugía , Neoplasias Uterinas/patología , Complicaciones Neoplásicas del Embarazo/patología , Complicaciones Neoplásicas del Embarazo/cirugía
2.
BMC Genomics ; 24(1): 760, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082218

RESUMEN

BACKGROUND: The functional roles of the Wall Associated Kinase (WAK) and Wall Associated Kinase Like (WAKL) families in cellular expansion and developmental processes have been well-established. However, the molecular regulation of these kinases in maize development is limited due to the absence of comprehensive genome-wide studies. RESULTS: Through an in-depth analysis, we identified 58 maize WAKL genes, and classified them into three distinct phylogenetic clusters. Moreover, structural prediction analysis showed functional conservation among WAKLs across maize. Promoter analysis uncovered the existence of cis-acting elements associated with the transcriptional regulation of ZmWAKL genes by Gibberellic acid (GA). To further elucidate the role of WAKL genes in maize kernels, we focused on three highly expressed genes, viz ZmWAKL38, ZmWAKL42 and ZmWAKL52. Co-expression analyses revealed that their expression patterns exhibited a remarkable correlation with GA-responsive transcription factors (TF) TF5, TF6, and TF8, which displayed preferential expression in kernels. RT-qPCR analysis validated the upregulation of ZmWAKL38, ZmWAKL42, ZmWAKL52, TF5, TF6, and TF8 following GA treatment. Additionally, ZmWAKL52 showed significant increase of transcription in the present of TF8, with ZmWAKL52 localizing in both the plasma membrane and cell wall. TF5 positively regulated ZmWAKL38, while TF6 positively regulated ZmWAKL42. CONCLUSIONS: Collectively, these findings provide novel insights into the characterization and regulatory mechanisms of specific ZmWAKL genes involved in maize kernel development, offering prospects for their utilization in maize breeding programs.


Asunto(s)
Fitomejoramiento , Zea mays , Humanos , Zea mays/metabolismo , Filogenia , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas
3.
Cleft Palate Craniofac J ; 60(4): 446-453, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34918551

RESUMEN

The common cold and/or an associated fever during pregnancy have/has been suspected to harm the developing fetus. We sought possible correlations between a maternal common cold or fever during pregnancy and the risk of orofacial clefts in the offspring.We systematically searched PubMed and Embase using appropriate keywords, and we checked the reference lists of retrieved articles. We used random-effects models to estimate overall relative risks.Incidence of orofacial clefts.We included 13 case-control studies. Modest but statistically significant associations were found between a maternal common cold and cleft lip with or without a cleft palate (CL/CP) (odds ratio [OR] 2.17; 95% confidence interval [CI] 1.66-2.83) and a cleft palate only (CPO) (OR 3.08; 95% CI 1.5-6.34). Furthermore, maternal fever was also associated with an increased risk of CL/CP (OR 1.91, 95% CI 1.3-2.8) and CPO (OR 1.48, 95% CI 0.83-2.63) in the offspring. Further analyses of maternal influenza (alone) yielded similar results.Although evidence of heterogeneity should be carefully evaluated, our findings suggest that maternal common cold or fever during pregnancy may be associated with a greater risk of CL/CP or CPO in the offspring. Future cohort studies using valid assessments of maternal common cold exposure during pregnancy that consider the severity of fever are needed to clarify the contribution of maternal common cold or fever status to the risk of orofacial clefts in children.


Asunto(s)
Labio Leporino , Fisura del Paladar , Resfriado Común , Femenino , Embarazo , Niño , Humanos , Labio Leporino/complicaciones , Fisura del Paladar/complicaciones , Resfriado Común/complicaciones , Factores de Riesgo , Estudios de Casos y Controles
4.
J Gastroenterol Hepatol ; 37(12): 2229-2242, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36068012

RESUMEN

BACKGROUND: N6-methyladenosine (m6A) is the most prevalent methylation modification of eukaryotic RNA, and methyltransferase-like 3 (METTL3) plays a vital role in multiple cell functions. This study aimed to investigate the role of m6A methylase METTL3 in slow transit constipation (STC). MATERIAL AND METHOD: The expression of METTL3 and DGCR8 was measured in STC tissues and glutamic acid-induced interstitial cells of Cajal (ICCs). The effects of METTL3, miR-30b-5p, and DGCR8 on the biological characteristics of ICCs were investigated on the basis of loss-of-function analyses. Luciferase reporter assay was used to identify the direct binding sites of miR-30b-5p with PIK3R2. RESULTS: The results showed that the METTL3, DGCR8, miR-30b-5p, and the methylation level of m6A were significantly increased in STC tissues and glutamic acid-induced ICCs. Silencing of METTL3 and miR-30b-5p inhibited apoptosis, autophagy, and pyroptosis of glutamic acid-induced ICCs. Moreover, overexpression of miR-30b-5p reversed the cytoprotection of METTL3 knockdown in glutamic acid-induced ICCs. Besides, DGCR8 knockdown could facilitate cell growth and decrease apoptotic glutamic acid-induced ICCs. Mechanically, we illustrated that METTL3 in glutamic acid-induced ICCs significantly accelerated the maturation of pri-miR-30b-5p by m6A methylation modification, resulting in the reduction of PIK3R2, which results in the inhibition of PI3K/Akt/mTOR pathway and ultimately leads to the cell death of STC. CONCLUSIONS: Collectively, these data demonstrated that METTL3 promoted the apoptosis, autophagy, and pyroptosis of glutamic acid-induced ICCs by interacting with the DGCR8 and successively modulating the miR-30b-5p/PIK3R2 axis in an m6A-dependent manner, and METTL3 may be a potential therapeutic target for STC.


Asunto(s)
Estreñimiento , MicroARNs , Proteínas de Unión al ARN , Humanos , Ácido Glutámico , Metiltransferasas , MicroARNs/genética , Fosfatidilinositol 3-Quinasas , Proteínas de Unión al ARN/genética , Serina-Treonina Quinasas TOR/genética , Estreñimiento/genética , Tránsito Gastrointestinal
5.
Opt Express ; 23(22): 29231-44, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26561193

RESUMEN

ZnO nanorods (NRs) self-organized into flowers were synthesized at different temperatures ranging from 100°C to 180°C by using the hydrothermal method. The existence of Zn interstitials (Zn(i)) was confirmed by X-ray photoelectron spectroscopy and a larger amount of Zn(i) was found in the ZnO NRs prepared at higher temperatures. A redshift of the emission peak of more than 15 nm was observed for the ZnO NRs under single photon excitation. The nonlinear optical properties of the flower-like ZnO NRs were characterized by using focused femtosecond laser light and strong three-photon-induced luminescence was observed at an excitation wavelength of ~750 nm. More interestingly, a large redshift of the emission peak was observed with increasing excitation intensity, resulting in efficient blue emission with a narrow bandwidth of ~30 nm. It was confirmed that the large redshift originates from the heating of the ZnO NRs to a temperature of more than 800°C and the closely packed ZnO NRs in the flowers play a crucial role in heat accumulation. The stable and efficient three-photon-induced blue emission from such ZnO NRs may find potential applications in the fields of optical display, high-temperature sensors and light therapy of tumors.

6.
Opt Express ; 22(23): 28086-99, 2014 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-25402049

RESUMEN

Periodic surface structures with periods as small as about one-tenth of the irradiating femtosecond (fs) laser light wavelength were created on the surface of a titanium (Ti) foil by exploiting laser-induced oxidation and third harmonic generation (THG). They were achieved by using 100-fs laser pulses with a repetition rate of 1 kHz and a wavelength ranging from 1.4 to 2.2 µm. It was revealed that an extremely thin TixOy layer was formed on the surface of the Ti foil after irradiating fs laser light with a fluence smaller than the ablation threshold of Ti, leading to a significant enhancement in THG which may exceed the ablation threshold of TixOy. As compared with Ti, the maximum efficacy factor for TixOy appears at a larger normalized wavevector in the direction perpendicular to the polarization of the fs laser light. As a result, the THG-dominated laser ablation of TixOy induces 100-nm periodic structures parallel to the polarization of the fs laser light. The depth of the periodic structures was found to be ~10 nm by atomic force microscopy and the formation of the thin TixOy layer was verified by energy dispersive X-ray spectroscopy.


Asunto(s)
Rayos Láser , Microscopía de Fuerza Atómica/instrumentación , Espectrometría por Rayos X/instrumentación , Titanio/química , Diseño de Equipo , Propiedades de Superficie
7.
Opt Lett ; 39(12): 3555-8, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24978535

RESUMEN

We report on the efficient blue light emission from In0.16Ga0.84N/GaN multiple quantum wells excited by femtosecond laser pulses with long wavelengths ranging from 1.24 to 2.48 µm. It is found that the trap states in GaN barrier layers lead to an efficient cascade multiphoton absorption in which the carriers are generated through simultaneous absorption of n (n=1 and 2) photons to the trap states, followed by simultaneous absorption of m (m=3, 4, and 5) photons to the conduction band. The dependence of the upconversion luminescence on excitation intensity exhibits a slope between n and n+m, which is in good agreement with the prediction based on the rate equation model.

8.
Appl Opt ; 53(2): 189-94, 2014 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-24514048

RESUMEN

We investigated the second and third harmonic generation (SHG and THG) in ZnO nanorods (NRs) by using a femtosecond laser (optical parametric amplifier with tunable wavelengths) with a long excitation wavelength of 1350 nm and a low repetition rate of 1 kHz. The damage threshold for ZnO NRs in this case was sufficiently large, enabling us to observe the competition between SHG and THG. The transition from red to blue emission and the mixing of red and blue light with different ratios were successfully demonstrated by simply varying excitation intensity, implying the potential applications of ZnO NRs in all-optical display.

9.
Eur J Obstet Gynecol Reprod Biol ; 299: 208-212, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38889572

RESUMEN

OBJECTIVE: This study aims to investigate the correlation between endometriosis (EMS) and adverse obstetric outcomes. METHODS: In this retrospective study 2,925 cesarean section cases were analyzed at the Women and Children's Hospital of Ningbo University, Department of Obstetrics, between May 2019 and December 2023. The study included 1,363 women diagnosed with endometriosis during pregnancy at the time of surgery (study group) and 1,562 women without such a diagnosis (control group). The comparative assessment covered the age of first-time mothers, number of pregnancies and births, gestational age at delivery, incidence rates of assisted reproductive technology (ART), spontaneous abortion, preterm birth, placenta previa, placental adhesion, and postpartum hemorrhage. RESULTS: The study group demonstrated a higher average age of first-time mothers, fewer pregnancies and births, and a significantly shorter gestational age at delivery (P < 0.05) compared to the control group. Incidences of primary infertility, spontaneous abortion, and ART utilization were higher in the study group. The occurrence of placenta previa, placental adhesion, and postpartum hemorrhage was also higher in the study group, indicating significant statistical differences (P < 0.05). No significant difference was observed in preterm birth rates between the groups (P > 0.05). CONCLUSION: Pregnancy in women with endometriosis is associated with a higher likelihood of adverse outcomes, therefore highlighting the need for increased clinical awareness.


Asunto(s)
Endometriosis , Complicaciones del Embarazo , Resultado del Embarazo , Humanos , Femenino , Embarazo , Endometriosis/epidemiología , Endometriosis/complicaciones , Adulto , Estudios Retrospectivos , Resultado del Embarazo/epidemiología , Complicaciones del Embarazo/epidemiología , Técnicas Reproductivas Asistidas/estadística & datos numéricos , Cesárea/estadística & datos numéricos , Cesárea/efectos adversos , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , China/epidemiología
10.
World J Clin Cases ; 12(16): 2881-2886, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38899312

RESUMEN

BACKGROUND: Granulomatosis with polyangiitis (GPA) is one of the most prevalent forms of the antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. GPA is characterized histologically by necrotizing granulomatous inflammation in addition to vasculitis. The diagnosis of GPA depends on clinical presentation, serological evidence of a positive ANCA, and/or histological evidence of necrotizing vasculitis or granulomatous destructive parenchymal inflammation. Cytoplasmic ANCA (c-ANCA) is positive in 65%-75% of GPA patients, accompanied by proteinase 3 (PR3), the main target antigen of c-ANCA, another 5% of GPA patients had negative ANCA. CASE SUMMARY: The patient, a 52-year-old male, presented with unexplained nasal congestion, tinnitus, and hearing loss. After a duration of 4 months experiencing these symptoms, the patient subsequently developed fever and headache. The imaging examination revealed the presence of bilateral auricular mastoiditis and partial paranasal sinusitis, and the ANCA results were negative. The anti-infective therapy proved to be ineffective, but the patient's symptoms and fever were quickly relieved after 1 wk of treatment with methylprednisolone 40 mg once a day. However, after continuous use of methylprednisolone tablets for 3 months, the patient experienced a recurrence of fever accompanied by right-sided migraine, positive c-ANCA and PR3, and increased total protein in cerebrospinal fluid. The patient was diagnosed with GPA. After receiving a treatment regimen of intravenous methylprednisolone 40 mg/d and cyclophosphamide 0.8 g monthly, the patient experienced alleviation of fever and headache. Additionally, the ANCA levels became negative and there has been no recurrence. CONCLUSION: For GPA patients with negative ANCA, there is a potential for early missed diagnosis. The integration of histopathological results and multidisciplinary communication plays a crucial role in facilitating ANCA-negative GPA.

11.
Mol Neurobiol ; 61(1): 519-532, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37644280

RESUMEN

Propofol is one of the most used intravenous anesthetic agents, which is widely used in clinical anesthesia induction and maintenance of pediatric patients. Exposure of the developing brain to propofol has been reported to lead to adverse brain changes, which in turn can induce persistent behavioral abnormalities in adulthood. However, the mechanisms by which propofol exposure in the developing brain induces cognitive impairment remain unclear. Here we report that repeated propofol exposure during the second postnatal week impairs spatial learning and memory in young mice. The reduced excitatory synaptic function and synaptogenesis in hippocampal CA1 neurons underlie this cognitive impairment. Propofol exposure specifically activates Toll-like receptor 4 (TLR4)-myeloid differentiation primary response protein 88 (MyD88)-NF-κB signaling pathway. TLR4 deficiency recues propofol exposure-induced synaptic function and cognitive deficits in young mice. Thus, we provide evidence that the activation of the TLR4-mediated pathway by propofol exposure may serve as a crucial trigger for the cognitive impairment in young adulthood caused by repeated exposure to propofol in the developing brain.


Asunto(s)
Disfunción Cognitiva , Propofol , Animales , Ratones , Anestésicos Intravenosos/toxicidad , Cognición , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/metabolismo , Hipocampo/metabolismo , Plasticidad Neuronal , Propofol/farmacología , Receptor Toll-Like 4/metabolismo
12.
Opt Express ; 21(4): 4439-46, 2013 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-23481977

RESUMEN

The femtosecond laser ablation of silicon surface near the ablation threshold was investigated and the preferential ablation along different directions was observed in different stages. It was found that the ripples formed in the initial stage facilitate the ablation along the direction perpendicular to the ripples, leading to the formation of an elliptical ablation area. With increasing length and depth of the ripples, however, nanohole arrays formed in the ripples will modify the distribution of electric field which benefits the ablation along the direction parallel to the ripples. Consequently, the ablation area is gradually changed to a circular one after irradiating sufficient number of pulses.


Asunto(s)
Rayos Láser , Nanopartículas/química , Nanopartículas/ultraestructura , Silicio/química , Silicio/efectos de la radiación , Nanopartículas/efectos de la radiación , Dosis de Radiación , Propiedades de Superficie/efectos de la radiación
13.
Nanotechnology ; 24(7): 075201, 2013 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-23358516

RESUMEN

We investigate systematically the competition between the second harmonic generation (SHG) and two-photon-induced luminescence (TPL) that are simultaneously present in Au nanoparticles excited by using a femtosecond (fs) laser. For a large-sized (length ~ 800 nm, diameter ~ 200 nm) Au nanorod, the SHG appears to be much stronger than the TPL. However, the situation is completely reversed when the Au nanorod is fragmented into many Au nanoparticles by the fs laser. In sharp contrast, only the TPL is observed in small-sized (length ~ 40 nm, diameter ~ 10 nm) Au nanorods. When a number of the small-sized Au nanorods are optically trapped and fused into a large-sized Au cluster by focused fs laser light, the strong TPL is reduced while the weak SHG increases significantly. In both cases, the morphology change is characterized by scanning electron microscope. In addition, the modification of the scattering and absorption cross sections due to the morphology change is calculated by using the discrete dipole approximation method. It is revealed that SHG is dominant in the case when the scattering is much larger than the absorption. When the absorption becomes comparable to or larger than the scattering, the TPL increases dramatically and will eventually become dominant. Since the relative strengths of scattering and absorption depend strongly on the size of the Au nanoparticles, the competition between SHG and TPL is found to be size dependent.

14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(10): 1315-9, 2013 Oct.
Artículo en Zh | MEDLINE | ID: mdl-24432670

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of PMC therapy (Prednisone, Methotrexate, Chloroquine) combined Langchuang Fuzheng Jiedu Capsule (LFJC), thus choosing a better therapy of integrative medicine for SLE in the period of glucocorticoid use. METHODS: Sixty active SLE patients were randomly assigned to two groups, the control group and the treatment group. Those in the control group received PMC therapy (As for Prednisone, it was given at the daily dose of 1 mg/kg till 2 weeks after the condition being stable or after 8 weeks of treatment. Then the dose was reduced by 10% every two weeks. When the dose was reduced to 0.5 mg/kg daily, it was reduced by 2.5 mg per two weeks. When the dose was reduced to 15 mg daily, the dose was reduced to 2.5 mg per four weeks. As for Methotrexate, 10 mg each time, once a week. As for Chloroquine, 100 mg each time, twice daily), while those in the treatment group received PMC therapy (the same way as that for the control group) combined with LFJC (consisting of Astragalus membranaceus 50 g, Angelica sinensis 20 g, Ligusticum Chuanxiong 20 g, prepared Rehmannia Rhizome 30 g, Herba Serissae 30 g, Centella 30 g, centipede 4 g, scorpions 10 g, nidus versace 12 g, et al., 0.5 g per pill, containing 5.7 g crude drug. When the hormone was given at a large dose, LFJC was administered at 12 pills each time, three times daily). When the hormone was given at a middle dose, LFJC was administered at 8 pills each time, three times daily. When the hormone was given at a small dose, LFJC was administered at 6 pills each time, three times daily. The treatment course was six months. The improvement of symptoms and signs between before and after treatment, SLE disease activity index (SLEDAI), efficacy of Chinese medical syndrome, UPro quantitation, erythrocyte sedimentation rate (ESR), complement 3 (C3), C-reactive protein (CRP), the reduction and withdrawal of hormones, and infection of the respiratory tract were observed. RESULTS: The difference in post-SLEDAI was obviously larger in the treatment group than in the control group (P < 0.05). The fatigue severity scale (FSS) was less after treatment than before treatment in the treatment group, showing statistical difference when compared with that of the control group (P < 0.05). The total effective rate was 93.33% in the treatment group, showing statistical difference when compared with that of the control group (86.66%; chi2 = 6.736, P < 0.05). The ESR decreased after treatment in the treatment group, showing statistical difference when compared with that of the control group (P < 0.01). C3 increased after treatment in the treatment group, showing statistical difference when compared with that of the control group (P < 0.05). The hormone was reduced to (13.70 +/- 5.42) mg/d by the end of the therapeutic course in the treatment group, obviously less than that of the control group [(17.63 +/- 7.80) mg/d, P < 0.05). Seven patients suffered from secondary infection of the respiratory tract infection in the treatment group (5 from upper respiratory tract infection and 2 from lower respiratory tract infection), obviously less than those of the control group (25 from upper respiratory tract infection and 10 from lower respiratory tract infection) (P < 0.05). CONCLUSIONS: PMC combined LFJC was a better treatment program for severe active SLE (SLEDAI > or = 15). It was more safe and effective when compared with using Western medicine alone. It could enhance the efficacy of hormones and help reduction/withdrawal of hormones.


Asunto(s)
Medicina Integrativa , Lupus Eritematoso Sistémico/tratamiento farmacológico , Fitoterapia/métodos , Adolescente , Adulto , Antiinflamatorios/uso terapéutico , Cloroquina/uso terapéutico , Quimioterapia Combinada , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Humanos , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Prednisona/uso terapéutico , Adulto Joven
15.
Opt Express ; 20(10): 10963-70, 2012 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-22565719

RESUMEN

We investigate the simultaneous trapping and melting of a large number of gold (Au) nanorods by using a single focused laser beam at 800 nm which is in resonance with the longitudinal surface plasmon resonance of Au nanorods. The trapping and melting processes were monitored by the two-photon luminescence of Au nanorods. A multi-ring-shaped pattern was observed in the steady state of the trapping process. In addition, optical trapping of clusters of Au nanorods in the orbits circling the focus was observed. The morphology of the structure after trapping and melting of Au nanorods was characterized by scanning electron microscope. It was revealed that Au nanorods were selectively melted in the trapping region. While Au nanorods distributed in the dark rings were completely melted, those located in the bright rings remain unmelted. The multi-ring-shaped pattern formed by the interference between the incident light and the scattered light plays an important role in the trapping and melting of Au nanorods.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanotecnología/métodos , Óptica y Fotónica , Diseño de Equipo , Calor , Interferometría/métodos , Rayos Láser , Luz , Microscopía Electrónica de Rastreo/métodos , Nanotubos/química , Fotones , Dispersión de Radiación , Resonancia por Plasmón de Superficie , Temperatura
16.
Opt Express ; 20(2): 905-11, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-22274437

RESUMEN

The high spatial frequency periodic structures induced on metal surface by femtosecond laser pulses was investigated experimentally and numerically. It is suggested that the redistribution of the electric field on metal surface caused by the initially formed low spatial frequency periodic structures plays a crucial role in the creation of high spatial frequency periodic structures. The field intensity which is initially localized in the grooves becomes concentrated on the ridges in between the grooves when the depth of the grooves exceeds a critical value, leading to the ablation of the ridges in between the grooves and the formation of high spatial frequency periodic structures. The proposed formation process is supported by both the numerical simulations based on the finite-difference time-domain technique and the experimental results obtained on some metals such as stainless steel and nickel.


Asunto(s)
Rayos Láser , Materiales Manufacturados , Níquel/química , Acero Inoxidable/química , Simulación por Computador , Análisis de Elementos Finitos , Microscopía Electrónica de Rastreo , Análisis Numérico Asistido por Computador
17.
Opt Express ; 20(9): 9616-23, 2012 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-22535053

RESUMEN

We proposed a method to assemble microspheres into a three-dimensional crystal by utilizing the giant nonequilibrium depletion force produced by nanoparticles. Such assembling was demonstrated in a colloid formed by suitably mixing silica microspheres and magnetic nanoparticles. The giant nonequilibrium depletion force was generated by quickly driving magnetic nanoparticles out of the focusing region of a laser light through both optical force and thermophoresis. The thermophoretic binding of silica beads is so tight that a colloidal photonic crystal can be achieved after complete evaporation of solvent. This technique could be employed for fabrication of colloidal photonic crystals and molecular sieves.


Asunto(s)
Cristalización/métodos , Rayos Láser , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestructura , Dióxido de Silicio/química , Nanopartículas de Magnetita/efectos de la radiación , Ensayo de Materiales , Dióxido de Silicio/efectos de la radiación , Estrés Mecánico
18.
Opt Lett ; 37(6): 1106-8, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22446240

RESUMEN

We report on the formation of one- and two-dimensional (1D and 2D) nanohole arrays on the surface of a silicon wafer by scanning with a femtosecond laser with appropriate power and speed. The underlying physical mechanism is revealed by numerical simulation based on the finite-difference time-domain technique. It is found that the length and depth of the initially formed gratings (or ripples) plays a crucial role in the generation of 1D or 2D nanohole arrays. The silicon surface decorated with such nanohole arrays can exhibit vivid structural colors through efficiently diffracting white light.

19.
J Neuroimmunol ; 368: 577896, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35660138

RESUMEN

We report an extremely rare case of hypertrophic pachymeningitis in which a 71-year-old man presented with an intractable recurrent headache for >1 year. During this period, he became positive for immunoglobulin G4 and proteinase 3-antineutrophil cytoplasmic antibodies. Contrast-enhanced magnetic resonance imaging showed characteristic diffuse thickening of the dura. Symptoms were improved by intravenous methylprednisolone (500 mg per day for 5 days) and cyclophosphamide pulse therapy during corticosteroid withdrawal; he remained symptom-free during 1-year follow-up. This case suggests that this disease can be treated by corticosteroids combined with immunosuppressive agents.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos , Meningitis , Corticoesteroides , Anciano , Humanos , Hipertrofia/diagnóstico por imagen , Inmunoglobulina G , Inmunosupresores/uso terapéutico , Imagen por Resonancia Magnética , Masculino , Meningitis/complicaciones , Meningitis/diagnóstico por imagen , Meningitis/tratamiento farmacológico
20.
Risk Manag Healthc Policy ; 15: 1315-1323, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35832904

RESUMEN

Objective: To discuss the application value of the plan-do-check-act (PDCA) cycle in shortening the decision to delivery interval (DDI) time. Methods: A total of 106 DDI cases from the Ningbo Women and Children's Hospital (China) from January 2019 to December 2020 were selected as the subjects of this study. The causes for the prolongation of DDI were analyzed and protocols were developed. Through continuous summaries and improvement, a standardized process was established to direct clinical application, ie, the PDCA cycle. Results: The DDI was shortened from 14.26 min in 2019 to 12.18 min in 2020 and the neonatal asphyxia rate significantly decreased from 34.69% in 2019 to 12.50% in 2020 (P < 0.05). Conclusion: The PDCA cycle management mode effectively shortened the DDI time and reduced the neonatal asphyxia rate, without increasing adverse maternal outcomes.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA