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Objective

This study explores the potential use of drones in searching for and locating victims and of motorized transportation of search and rescue providers in a mountain environment using a simulation model.

Methods

This prospective randomized simulation study was performed in order to compare two different search and rescue techniques in searching for an unconscious victim on snow-covered ground. In the control arm, the Classical Line Search Technique (CLT) was used, in which the search is performed on foot and the victim is reached on foot. In the intervention arm, the Drone-snowmobile Technique (DST) was used, the search being performed by drone and the victim reached by snowmobile. The primary outcome of the study was the comparison of the two search and rescue techniques in terms of first human contact time.

Results

Twenty search and rescue operations were conducted in this study. Median time to arrival at the mannequin was 57.3 min for CLT, compared to 8.9 min for DST. The median value of the total searched area was 88,322.0 m2 for CLT and 228,613.0 m2 for DST. The median area searched per minute was 1489.6 m2 for CLT and 32,979.9 m2 for DST (p < 0.01 for all comparisons).

Conclusions

In conclusion, a wider area can be searched faster by drone using DST compared to the classical technique, and the victim can be located faster and reached earlier with rescuers transported by snowmobile.  相似文献   
105.
Uzuner  Selcuk  Durcan  Gizem  Sahin  Sezgin  Bahali  Kayhan  Barut  Kenan  Kilicoglu  Ali Guven  Adrovic  Amra  Bilgic  Ayhan  Kasapcopur  Ozgur 《Clinical rheumatology》2021,40(12):5025-5032
Clinical Rheumatology - Having a child with a chronic illness is a source of stress for the whole family, especially the primary caregiver. The aim of this study was to evaluate the associations...  相似文献   
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Purpose

Splenectomy is associated with increased risk of overwhelming post-splenectomy infections despite proper anti-pneumococcal vaccination. As most studies concentrated on vaccination-induced humoral immunity, the cellular immune responses triggered in splenectomized patients are not yet well studied. The present study aims to investigate this area as it can contribute to the development of more effective vaccination strategies.

Methods

Five healthy and 14 splenectomized patients were vaccinated with pneumococcal conjugate polysaccharide vaccine (PCV) followed by pneumococcal polysaccharide vaccine according to the guidelines established by Advisory Committee on Immunization Practices. PBMC samples collected 0, 8, and 12 weeks after PCV immunization were in vitro stimulated with PCV. Levels of lymphoproliferation, TH cell differentiation, and cytokine release were assessed by carboxyfluorescein succinimidyl ester labeling, intracellular cytokine staining, and ELISA, respectively.

Results

While TH1-dominated immune response was detected in both groups, asplenic individuals generated significantly lower levels of TH1 cells following in vitro stimulation. Similarly, levels of IFN-γ, IL-4, and IL-17 release and lymphoproliferation were significantly lower in asplenic patients.

Conclusions

According to our data, splenectomy negatively influences the levels of PCV-induced lymphoproliferation, TH1 differentiation, and cytokine release. Besides, PCV failed to induce TH17-dominant immune response which is crucial for protection against extracellular pathogens.
  相似文献   
110.

Introduction

Serum leptin levels have been examined in various cancers, with conflicting results. However, there is limited information regarding serum leptin levels and insulin resistance in gastric cancer patients. Therefore, we aimed to investigate serum leptin levels, performance status, insulin levels and insulin resistance in patients with gastric cancer. In addition, we examined the relationship between these measurements and leptin levels.

Material and methods

Thirty-nine patients with gastric cancer and 30 control subjects were enrolled in the study. Serum leptin, total protein, albumin, growth hormone, insulin and glucose levels were measured. The homeostasis model assessment (HOMA) was used to assess insulin resistance.

Results

Serum levels of insulin, glucose and growth hormone and insulin resistance were significantly lower in gastric cancer patients than controls (p < 0.05 for all). In the Pearson correlation analysis, insulin resistance was found to be significantly correlated with serum leptin levels in gastric cancer patients (r = 0.320, p = 0.047). We observed a significant negative correlation between performance status and insulin resistance in patients with cachexia (r = –0.512, p = 0.030), while no association was found in non-cachectic patients.

Conclusions

We concluded that serum leptin levels are significantly lower in gastric cancer patients. In addition, gastric cancer patients have decreases in insulin levels, insulin resistance and growth hormone levels. This study found a positive association between serum leptin levels and insulin resistance. Moreover, there is a negative association between serum leptin levels and growth hormone levels. Thus, low insulin and growth hormone levels may suppress the production of leptin in gastric cancer patients.  相似文献   
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