156 research outputs found

    Existence of Monotone Positive Solution of Neutral Partial Difference Equation

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    AbstractThis paper is concerned with a class of neutral partial difference equations. The conditions for the existence of monotone eventually positive solutions are established which improve and extend some of the criteria existing in the literature. Comparison theorems are also derived. Results are obtained on the existence of a monotone eventually positive solution of dual equation

    Laparoscopic versus open distal pancreatectomy: A meta-analysis

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    SummaryObjectiveLaparoscopic distal pancreatectomy (LDP) is a minimally invasive surgical technique. The aim of the present study was to evaluate the currently available literature and compare the short-term clinical outcomes of patients who underwent LDP for left-sided pancreatic pathology with patients who underwent traditional open surgery.MethodsA literature search was performed to identify and compare studies that reported the clinical outcomes of both LDP and open distal pancreatectomy (ODP). Pooled odds ratios (OR) and weighted mean differences (WMD) with 95% confidence intervals (95% CI) were calculated using either fixed-effects or random-effects models.ResultsNineteen nonrandomized controlled studies were identified that matched the selection criteria and reported the clinical outcomes of 1935 patients, of whom 805 underwent LDP and 1130 underwent ODP. Compared with open surgery, reports on laparoscopic resection indicate potentially favorable outcomes in terms of operative blood loss (WMD: -273.11; 95% CI: -404.61 to -141.61), the requirement of a blood transfusion (OR: 0.28; 95% CI: 0.11–0.71), postoperative time until oral intake (WMD: -1.19; 95% CI: -1.87 to -0.50), time to first flatus (WMD: -1.03, 95% CI: -1.93 to -0.12), length of hospital stay (WMD: -3.87, 95% CI: -5.06 to -2.68), and overall morbidity (OR: 0.70, 95% CI: 0.56–0.87). There were no differences in terms of the extent of oncologic clearance and postoperative mortality.ConclusionLDP results in a faster postoperative recovery and a comparable oncologic clearance in comparison with open surgery. Additional large trials are required to delineate the long-term clinical outcomes of patients diagnosed with malignant neoplasms who undergo either of these two surgeries

    Solitary hepatic lymphangioma: a one-case report

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    Hepatic lymphangiomas, malformations of the liver lymphatic system, are extremely rare conditions in adults. A 41-year-old man presented with right upper abdominal pain for 6 months was introduced in this report. Ultrasound (US) and computed tomography (CT) scan demonstrated a giant cystictumor with a pedunculatedextrahepatic growth pattern. Due to diagnostic uncertainty, a partial hepatectomy was performed and pathological results confirmed the diagnosis of solitary hepatic lymphangioma. In this article, we reviewed the clinical and pathology features, preoperative diagnostic challenges, and treatments of hepaticlymphangiomas

    Deformation and Failure Mechanism of the Lower Roadway in a Close-Range Residual Coal Pillar Area

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    The Tashan coal mine is selected as a case study to determine the deformation and damage mechanisms of the lower roadway in a close-range residual coal pillar area. Roof drilling peephole technology is applied to detect the damage to the roadway roof surrounding rock. A boundary invisibility equation is derived for the plastic zone of a circular hole based on the theory of a butterfly plastic zone in a non-uniform stress field in which the principal stress occurs at an arbitrary angle to the vertical. Maple mathematical drawing software is combined with FLAC3D numerical simulations to investigate the influence of the principal stress ratio and direction on the roadway plastic zone. The results indicate that the plastic zone of the roadway surrounding rock assumes a butterfly shape when the bidirectional stress ratio is large, and the direction of the butterfly-shaped failure of the roadway is related to the principal stress direction. Field test images are combined to show that the asymmetric damage pattern of the lower roadway in a close-range residual coal pillar area is influenced by the presence of the roadway in a non-uniform stress field in which the main stress direction is deflected

    Facile bioactive transformation of magnesium alloy surfaces for surgical implant applications

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    The market for orthopedic implant alloys has seen significant growth in recent years, and efforts to reduce the carbon footprint of medical treatment (i.e., green medicine) have prompted extensive research on biodegradable magnesium-based alloys. Magnesium alloys provide the mechanical strength and biocompatibility required of medical implants; however, they are highly prone to corrosion. In this study, Mg-9Li alloy was immersed in cell culture medium to simulate degradation in the human body, while monitoring the corresponding effects of the reaction products on cells. Variations in pH revealed the generation of hydroxyl groups, which led to cell death. At day-5 of the reaction, a coating of MgCO3 (H2O)3, HA, and α -TCP appeared on sample surfaces. The coating presented three-dimensional surface structures (at nanometer to submicron scales), anti-corrosion effects, and an altered surface micro-environment conducive to the adhesion of osteoblasts. This analysis based on bio-simulation immersion has important implications for the clinical use of Mg alloys to secure regenerated periodontal tissue

    Mimotopes selected with neutralizing antibodies against multiple subtypes of influenza A

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    <p>Abstract</p> <p>Background</p> <p>The mimotopes of viruses are considered as the good targets for vaccine design. We prepared mimotopes against multiple subtypes of influenza A and evaluate their immune responses in flu virus challenged Balb/c mice.</p> <p>Methods</p> <p>The mimotopes of influenza A including pandemic H1N1, H3N2, H2N2 and H1N1 swine-origin influenza virus were screened by peptide phage display libraries, respectively. These mimotopes were engineered in one protein as multi- epitopes in Escherichia coli (E. coli) and purified. Balb/c mice were immunized using the multi-mimotopes protein and specific antibody responses were analyzed using hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA). The lung inflammation level was evaluated by hematoxylin and eosin (HE).</p> <p>Results</p> <p>Linear heptopeptide and dodecapeptide mimotopes were obtained for these influenza virus. The recombinant multi-mimotopes protein was a 73 kDa fusion protein. Comparing immunized infected groups with unimmunized infected subsets, significant differences were observed in the body weight loss and survival rate. The antiserum contained higher HI Ab titer against H1N1 virus and the lung inflammation level were significantly decreased in immunized infected groups.</p> <p>Conclusions</p> <p>Phage-displayed mimotopes against multiple subtypes of influenza A were accessible to the mouse immune system and triggered a humoral response to above virus.</p
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