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1.
Cancers (Basel) ; 16(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38672678

RESUMO

Colorectal cancer is the third most common cancer worldwide, and the liver is the most common localization of metastatic disease. The incidence of minimally invasive liver surgery is increasing, and robotic surgery (RLR) is believed to overcome some limitations of a laparoscopic approach (LRL). We performed a systematic review and meta-analysis of operative and short-term oncologic outcomes of the laparoscopic versus robotic-assisted liver resection for colorectal liver metastases. An online search of PubMed, Embase, Scopus, and the Cochrane databases was performed. Eight studies involving 3210 patients were considered eligible for the meta-analysis. In the LRL group, a higher conversion to open rate (12.4%) was observed compared to the RLR (6.7%; p = <0.001). 30-day mortality was 0.7% for the LRL group compared to 0.5% for the RLR group (p = 0.76). Mortality in longer periods among LLR and RLR amounted to 18.2% vs. 8.0% for 1-year mortality (p = 0.07), 34.1% vs. 26.7% for 2-year mortality (p = 0.13), and 52.3% vs. 48.3% for 3-year mortality (p = 0.46). The length of hospital stay was 5.6 ± 2.5 vs. 5.8 ± 2.1 days, respectively (p = 0.47). There were no significant differences between the incidence of individual complications in the LRL and RLR groups (p = 0.78). Laparoscopic or robotic approaches for colorectal liver metastases are comparable in terms of safety and effectiveness. There are significant advantages to robotic surgery, although there is still no long-term evidence concerning overall survival, and the number of patients operated on using RLR remains small.

2.
Environ Technol ; 33(13-15): 1781-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22988640

RESUMO

The aim of this research was to apply a simple and quick method of size and shape characterization by TEM to diesel exhaust particles from large-capacity, high-performance trucks. Particulate matter (PM) samples were collected while the engines were idling. Investigation of this type of emission is essential because vehicles are idling at stop lights, in traffic, or during slow movement, goods loading and unloading. In these conditions, PM emission cumulates in a small area. It was found that PM from vehicle exhaust emissions can be divided into three groups: soot, irregular-shaped particles and circular particles. Irregular-shaped particles and soot aggregates were present in the exhausts of the three types of vehicle tested. Circular particles were identified only in the samples collected from exhaust emissions from the MAN vehicle, and were present in small amounts. The average surface area was in the range of 0.06 microm2 to 0.24 microm2. Mean perimeter fluctuated from 2.09 microm to 4.14 microm, and Feret diameter from 0.21 microm to 0.31 microm. Circularity was in the range of 0.12 to 0.30. Aspect ratio was around 0.30 to 0.45. Feret diameter seems to be a good parameter to define the mean size of particles, but does not take into account the influence of the shape. Therefore, this measurement seems to be useful just in the case of spherical or very rounded particles, not for all diesel PM. Thus, it is necessary to consider circularity or aspect ratio for DPM characterization.


Assuntos
Poluentes Atmosféricos/análise , Microscopia Eletrônica de Transmissão/métodos , Tamanho da Partícula , Emissões de Veículos/análise , Monitoramento Ambiental/métodos , Veículos Automotores
3.
Anal Bioanal Chem ; 399(9): 3261-70, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21110012

RESUMO

The objectives of this work were to develop a means of sampling atmospheric dusts on the premises of an oil refinery for electron microscopic study to carry out preliminary morphological analyses and to compare these dusts with those collected at sites beyond the refinery limits. Carbon and collodion membranes were used as a support for collection of dust particles straight on transmission electron microscopy (TEM) grids. Micrographs of the dust particles were taken at magnifications from ×4,000 to ×80,000 with a Tesla BS500 transmission electron microscope. Four parameters were defined on the basis of the micrographs: surface area, Feret diameter, circumference, and shape coefficient. The micrographs and literature data were used to classify the atmospheric dusts into six groups: particles with an irregular shape and rounded edges; particles with an irregular shape and sharp edges; soot and its aggregates; spherical particles; singly occurring, ultrafine dust particles; and particles not allocated to any of the previous five groups. The types of dusts found in all the samples were similar, although differences did exist between the various morphological parameters. Dust particles with the largest Feret diameter were present in sample 3 (mean, 0.739 µm)-these were collected near the refinery's effluent treatment plant. The particles with the smallest diameter were found in the sample that had been intended to be a reference sample for the remaining results (mean, 0.326 µm). The dust particles collected in the refinery had larger mean Feret diameters, even 100% larger, than those collected beyond it. Particles with diameters from 0.1 to 0.2 µm made up the most numerous group in all the samples collected in the refinery.


Assuntos
Poluentes Atmosféricos/química , Poeira/análise , Monitoramento Ambiental/métodos , Microscopia Eletrônica de Transmissão/métodos , Tamanho da Partícula
4.
Crit Rev Anal Chem ; 41(4): 314-334, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-28094548

RESUMO

The present article reviews studies on air solid particles carried out with the use of electron microscopy. Particle analysis combining scanning and transmission electron microscopy (SEM and TEM) can be used to derive size-resolved information of the composition, mixing state, morphology, and complex refractive index of atmospheric aerosol particles. It seems that electron microscopy is more widely used in atmospheric particulate matter analysis, but the usage of this method is sometimes problematic. First of all, there is no standard methodology adapted for dust analysis, and it is difficult to compare the results coming from different laboratories. Nevertheless, it was shown that this method has potential to be used in the future as a standard monitoring procedure of air solid particles.

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