Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Urol Int ; 107(1): 87-95, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35537444

RESUMO

INTRODUCTION: The aim of this study was to implement our technique for the initial dissection of the inferior hypogastric plexus and protection of the autonomic nerve supply to the corpora cavernosa in laparoscopic radical cystoprostatectomy with an orthotopic ileal neobladder and report the initial outcomes. METHODS: Eleven normally potent patients with preoperative cT2N0 bladder cancer who underwent bilateral nerve-sparing laparoscopic cystoprostatectomy performed by the same surgeon were selected from May 2018 to September 2020. In this procedure, the anterior part of the inferior hypogastric plexus was dissected first between the prehypogastric nerve fascia and rectal proper fascia medial to the distal ureter. Then the Denonvilliers' fascia and the nerves around the prostate were preserved according to current intrafascial principles. The preliminary operative, oncologic, and functional results are presented. RESULTS: The median follow-up duration was 18 months. We observed early and late complications in 5 patients, but none exceeded grade III. Of the 11 patients, ten gained daytime continence (90.9%), and 8 (72.7%) showed nocturnal continence at the last follow-up. Regarding postoperative potency, 10 of the 11 patients (90.9%) remained potent with or without oral medications, excluding one who had partial tumescence but did not follow our recommendations regarding medication use. No local recurrence or positive surgical margins were noted. CONCLUSION: In addition to emphasizing our cavernosal nerve-sparing procedure, this report on the precise dissection and protection of the inferior hypogastric plexus could be of clinical significance, providing potentially ideal short-term functional results.


Assuntos
Laparoscopia , Próstata , Masculino , Humanos , Plexo Hipogástrico , Bexiga Urinária , Laparoscopia/métodos , Pelve
2.
Nanomaterials (Basel) ; 11(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443954

RESUMO

Graphene has been widely used as a lubricating additive to reduce the energy consumption of engines and improve fuel economy because of its unique crystal structure. Herein, graphene (GR) and fluorinated graphene (F-GR) nanoparticles were prepared by ball milling and liquid-phase exfoliation. The SEM/EDS, HRTEM, XPS, Raman spectrometer, X-ray spectrometer, FTIR were used to investigate the morphologies, surface groups, and crystal structure of two kinds of graphene materials. The influence of loads on the tribological properties of two kinds of particles was investigated in Poly Alpha Olefin (PAO6) using a UMT-2 reciprocating tribometer. Results showed that the crystal structure of GR is better than F-GR. F-GR can improve the lubrication performance of PAO6. For PAO6 containing 1 wt% F-GR at 10 N, the average friction coefficient and average wear rate decreased by 12.3% and 87% relative to pure PAO6, respectively. However, the high load resulted in an inconspicuous anti-wear and anti-friction effect. The influence of F-GR on the tribological behavior of PAO6 was more substantial than that of GR. The friction and wear mechanisms attributed to F-GR quickly entered the interface between the friction pairs. Friction-induced F-GR nanosheets mainly took the tribo-chemical reactions to participate in the lubrication film formation and helped achieve a low friction coefficient and wear rate.

3.
Nanomaterials (Basel) ; 9(8)2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31382556

RESUMO

The objective of this study was to investigate the roles and tribological mechanisms of onion-like carbon nanoparticles derived from biodiesel soot (BDS) when applied in water (H2O) and liquid paraffin (LP). In this study, we prepared nitric acid-treated BDS (NA-BDS) as an additive to H2O and NA-BDS modified with oleylamine (NA-BDS-OLA) as an additive to LP. Raman spectroscopy, field-emission transmission electron microscopy, Fourier transform infrared spectroscopy, and zeta potentiometry were used to characterize the results of the nitric acid treatment and oleylamine modification. The tribological behaviors and corresponding mechanisms of the new onion-like carbon nanoparticles were evaluated using a ball-on-disc reciprocating tribometer, as well as field-emission scanning electron microscopy, three-dimensional laser scanning microscopy, and Raman spectroscopy. The results indicated that the additives NA-BDS and NA-BDS-OLA, which were onion-like carbon nanoparticles with sizes ranging from 35 to 40 nm, enhanced the antiwear and friction reduction properties of H2O and LP, respectively. Through tribo-mechanisms, these types of soot can serve as spacers and ball bearings between the rubbing surfaces. Moreover, exfoliation under a high load as a result of the formation of a graphitic layer facilitates easy shearing.

4.
Bioresour Technol ; 156: 1-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24472700

RESUMO

This paper investigated a novel hydrothermal liquefaction process of Chlorella pyrenoidosa catalyzed by Ce/HZSM-5. The chemical groups and components of the residues of C. pyrenoidosa were analyzed by Fourier transform infrared spectrometry and Gas Chromatograph-Mass Spectrometer. The crystal structure and micro surface topography of C. pyrenoidosa before and after catalytic liquefaction were characterized by X-ray diffraction and Scanning electron microscopy, respectively. The experimental results showed that the catalytic cracking effects of Ce/HZSM-5 were superior to that of HZSM-5 as a liquefaction catalyst of C. pyrenoidosa. Compared with HZSM-5, Ce/HZSM-5 has a significantly enhanced Lewis acid active center, smaller particle size, larger specific surface, and highly dispersed Ce4O7 with trivalent and tetravalent cerium in the zeolite skeleton channel that accelerate the catalytic liquefaction of C. pyrenoidosa. The rare earth modified zeolite Ce/HZSM-5 exhibits good potential and a beneficial nature for the preparation of bio-oil from microalgae with high efficiency.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Cério/farmacologia , Chlorella/metabolismo , Óleos/metabolismo , Zeolitas/farmacologia , Catálise , Chlorella/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Água/química , Difração de Raios X
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA