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Objective:To investigate the regularity of lymph node metastasis of gastrocolic ligament in colon cancer at hepatic flexure,and to explore the feasibility and necessity of the dissection.Methods:The dissection number and the metastasis number of gastrocolic lymph nodes in 96 patients with colon cancer on the hepatic flexure were analyzed retrospectively.The related factors affecting the lymph node metastasis of gastrocolonic ligament were analyzed.Results:Lymph node metastasis of gastrocolic ligament was found in 7 of 96 patients, and the metastasis rate was 7%. Metastasis was found in all three parts of gastrocolic lymph node. Gastrocolic lymph nodes metastasis were related to perineural invasion,tumor budding, N stage and intestinal obstruction (all P<0.05). Conclusion:The dissection of gastrocolic lymph node of hepatic flexure colon cancer is safe and feasible, and can provide more accurate pathological staging, which provides a basis for follow-up adjuvant therapy.
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In indoor environments with limited ventilation, recirculating portable air filtration (PAF) units may reduce COVID-19 infection risk via not only the direct aerosol route (i.e., inhalation) but also via an indirect aerosol route (i.e., contact with the surface where particles deposited). We systematically investigated the impact of PAF units in a mock classroom, as a supplement to background ventilation, on localized and whole-room surface deposition and particle concentration. Fluorescently tagged particles with a volumetric mean diameter near two micrometers were continuously introduced into the classroom environment via a breathing simulator with a prescibed inhalation-exhalation waveform. Deposition velocities were inferred on >50 horizontal and vertical surfaces throughout the classroom, while aerosol concentrations were spatially monitored via optical particle spectrometry. Results revealed a particle decay rate consistent with expectations based upon the reported clean air delivery rates of the PAF units. Additionally, the PAF units reduced peak concentrations by a factor of around 2.5 compared to the highest concentrations observed and led to a statistically significant reduction in deposition velocities for horizontal surfaces >2.5 m from the aerosol source. Our results not only confirm PAF units can reduce particle concentrations but also demonstrate that they may lead to reduced particle deposition throughout an indoor environment when properly positioned. Practical ImplicationsO_LIPortable air filtration units should be prioritized in classrooms as part of a multi-layed strategy to mitigate potentially infectious particle transmission by direct aerosol transmission via inhalation and indirect aerosol transmission via particle deposition to surfaces and later contact with said surfaces. C_LIO_LIWhen placing portable air filtration unit(s) within a classrom space, one should consider the airflow field within the classroom, the characteristic operational mode (heating vs. cooling) of the heating, ventilation, and air conditioning system, the predominantly occupied areas of the classroom, and interference with the regular teaching and learning activities. C_LI
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Objective:To compare the results of lymph node dissection boundaries along the right or left sides of SMA in laparoscopic radical resection for right colon cancer.Methods:One hundred and two patients with advanced right colon cancer were selected for retrospective analysis, the patients were divided into study group (48 cases) and control group (54 cases) according to the extent of lymph node resection. The medial boundary of lymph node dissection in the study group was on the left side of SMA, and the control group was on the right side of SMA. The operation duration, hospital stays, CRP(postoperative day 1), the number of dissected lymph nodes and the complications were compared.Results:The operation duration of the study group was longer than that of the control group[(169±24)min vs.(138±28)min, t=4.827, P<0.05], but there was no statistically significant difference in hospital stays[(10.5±1.7)d vs.(9.7±2.0)d, t=1.172, P>0.05], CRP(postoperative day 1) [(110±44)mg/L vs.(100±39)mg/L, t=1.287, P>0.05], incidence of postoperative complication(12 cases vs. 9 cases, P>0.05) between the two groups.The number of lymph nodes removed in the study group was more than that in the control group[(23.8±8.2) vs.(19.7±6.8), t=2.191, P<0.05], though the number of positive lymph nodes removed in the two groups was not significantly different[(2.2±4.9) vs.(1.4±2.8), t=0.863, P>0.05]. Conclusions:Laparoscopic radical resection for right colon cancer along the left sides of SMA removed more lymph nodes without significant increase of the surgical complications.
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Objective To study the effects of mechanical load on in vivo degradation performance of high-purity magnesium (HP Mg, 99.99 wt.%) quantitatively. Methods Cylindrical Mg specimens, with a 2 mm diameter and a 14 mm length, were mounted in polyetheretherketone (PEEK) rings to bear compressive stresses ［（6.2±0.6） MPa］, tensile stresses ［（4.6±0.1） MPa］ or no stress (as control). The specimens under different stress states were implanted subcutaneously in dorsal abdominal regions of SD rats for 4 weeks. The mass loss, residual volume and surface morphology of the specimens and staining of surrounding soft tissues were used to analyze the degradation rate of HP Mg. Results Specimens and rings were completely encapsulated by membranous tissues after implantation for 4 weeks. No significant differences in the degradation rates were noted between specimens bearing stress and the control. The corrosion layers of specimens under each stress state were uniform. Conclusions The compressive and tensile stresses (4-6 MPa) could not affect significantly HP Mg degradation performance in vivo. The research findings provide theoretical references for the design and clinical application of Mg-based degradable implants.
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Three-dimensional poly (epsilon-caprolactone)/silk sericin (PCL/SS) porous nanofibrous scaffolds were prepared by electrospinning. The structure and properties of the scaffolds were characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and water contact angle instrument. Studies on cell adhension and proliferation were carried out by culturing human primary skin fibroblast cells (FEK4) on these scaffolds using SEM and MTS. The experimental results showed that the PCL/SS nanofibrous scaffolds with SS nanoparticles had porous non-woven mesh structure with nanofibrous cross-linked with each other. Fiber diameter was very uniform and precise, and the secondary structure of SS protein had not been changed. Furthermore, the capability of hydrophile increased with the SS addition, which improved FEK4 cells adhesion and proliferation on the scaffolds.
Subject(s)
Biocompatible Materials , Chemistry , Cell Adhesion , Cells, Cultured , Fibroblasts , Cell Biology , Microscopy, Electron , Nanofibers , Chemistry , Polyesters , Chemistry , Sericins , Chemistry , Silk , Chemistry , Spectroscopy, Fourier Transform Infrared , Tissue Scaffolds , ChemistryABSTRACT
Objective To investigate the expression and sensitivity of 6 muhidmg resistance gene products(MDR) : GST-π、LRP、MRP、Topo Ⅱ、P-gp、TS in gastric cancer during neoadjuvant chemotherapy. Methods Expression of the 6 muhidrug resistance gene was detected by immunohistoehemistry in 35 cases of stomach cancer tissues before and after neoadjuvant chemotherapy. The relationship between muhidrug resistance gene and neoadjuvant chemotherapy was analyzed. All patients were given FOLFOX4, and the effects were evaluated according to World Health Organization criteria. Results The overall response rates to chemotherapy was 46%, expression of the 6 mtdtidrug resistance gene in 35 cases of stomach cancer tissues were as follows:GST-π was 40% ,LRP was 69% ,MRP was 34% ,Topo Ⅱ was 37% ,P-gp was 86%, TS was 40%, expression of the 6 muhidrug resistance gene did not change during neoadjuvant chemotherapy; GST-π、LRP、MRP、Topo Ⅱ、P-gp were not correlated with chemotherapy sensitivity(P > 0.05), while TS was significantly correlated with chemotherapy sensitivity (P = 0.0048). Conclusion FOLFOX4 does not effect a change in the expression of the 6 muhidrug resistance gene: GST-π、LRP、MRP、Topo Ⅱ、P-gp and TS, while TS is significantly correlated with gastric cancer chemotherapy sensitivity.
