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961.

Introduction

The study aimed to clarify the difficulties concerning insertion of advanced airway devices during cardiac arrest.

Method

In an observational study using manikins, we examined the airway management techniques of 19 teams at the Osaka Senri medical rally. For ex-post verification, we recorded chest compression and ventilation using the Resusci® Anne Advanced Skill Trainer (Laerdal, Norway) and recorded actions of the teams using a video camera.

Results

Only a small proportion of teams did not adopt advanced airway management (4 teams, 21.1%). Thirteen teams selected tracheal intubation. None showed chest compression interruptions during intubation manipulation, and the median duration of chest compression interruption during confirmation of postintubation was 6.4 seconds. The median duration of ventilation interruption during intubation was 45.5 seconds. When teams were evaluated for the duration of direct laryngoscopy, that is, so-called duration of intubation, the median duration was 19 seconds, which constituted a large underestimate compared with the duration of ventilation interruption. This represents an underestimation of about 27 seconds. We considered the issues to be identified for shortening the duration of ventilation interruption.

Conclusion

From this study, it is clear that the strategy of Guideline 2005 that was designed to minimize chest compression interruption has permeated deeply. The recommendation that the duration of intubation manipulation should not exceed 30 seconds has had various interpretations, but it is important to focus on the duration of ventilation interruption.  相似文献   
962.
963.
964.
Diffuse optical tomography (DOT) is an advanced imaging method used to visualize the internal state of biological tissues as 3D images. However, current continuous-wave DOT requires high-density probe arrays for measurement (less than 15-mm interval) to gather enough information for 3D image reconstruction, which makes the experiment time-consuming. In this paper, we propose a novel DOT measurement system using multi-directional light sources and multi-directional photodetectors instead of high-density probe arrays. We evaluated this system’s multi-directional DOT through computer simulation and a phantom experiment. From the results, we achieved DOT with less than 5-mm localization error up to a 15-mm depth with low-density probe arrays (30-mm interval), indicating that the multi-directional measurement approach allows DOT without requiring high-density measurement.OCIS codes: (100.3010) Image reconstruction techniques, (110.0113) Imaging through turbid media, (170.3880) Medical and biological imaging  相似文献   
965.
ObjectiveWe describe a case of intracranial and extracranial multiple arterial dissecting aneurysms in rheumatoid arthritis (RA).Case PresentationA 29-year-old man with a medical history of RA since 18 years of age was admitted to our hospital for vomiting, dysarthria, and conscious disturbance. At 23, he underwent ligation of the left internal carotid artery (ICA) with superficial temporal artery to middle cerebral artery anastomosis because of acute infarct of the left hemisphere caused by arterial dissection of the left ICA. During the current admission, computed tomography (CT) revealed subarachnoid hemorrhage, and digital subtraction angiography (DSA) demonstrated dissecting aneurysms of the left intracranial vertebral artery (VA) and right extracranial VA. We diagnosed him with a ruptured dissecting aneurysm of the left intracranial VA and performed endovascular parent artery occlusion on the left VA. For the right unruptured VA aneurysm, we performed coil embolization simultaneously. At 2 weeks after the endovascular treatment, follow-up DSA revealed that multiple de novo dissecting aneurysms developed on the origin of the left VA and left and right internal thoracic arteries. Those aneurysms were treated with coil embolization. Other remaining aneurysms on the left thyrocervical trunk, right transverse cervical artery, and both common iliac arteries were treated by conservative therapy. While continuing medical treatment for RA, the patient recovered and was discharged to a rehabilitation hospital.ConclusionConsidering that RA-induced vasculitis can be a potential risk of vascular complications including multiple arterial dissections, physicians should carefully perform endovascular interventional procedures for patients with long-term RA.  相似文献   
966.
A 46-year-old man with alcoholic cirrhosis was admitted to our hospital for treatment of high-risk esophageal varices in February 2000. Images of the esophageal varices, paraesophageal veins and palisade veins were obtained by endoscopic color Doppler ultrasonography (ECDUS) before endoscopic injection sclerotherapy (EIS). Prophylactic EIS was performed six times per week for esophageal varices, and EIS was continued until the esophageal varices were completely eradicated. In July 2002, endoscopy revealed esophageal varices graded as Cb, F1, Lm, and RC(−), and color flow images of the palisade veins (hepatofugal flow), esophageal varices, and a developed paraesophageal vein were obtained with ECDUS. In April 2003, endoscopy showed esophageal varices graded as Cb, F1, Lm, and RC(−), and color flow images of the palisade veins and esophageal varices were obtained using ECDUS. The blood in the palisade veins flowed in an alternate direction on color flow images, and pulsatile waves were delineated at the gastroesophageal junction. In January 2004, endoscopy revealed esophageal varices graded as F0 and RC(−), and pulsatile waves were delineated in the lower esophagus with ECDUS. However, the esophageal varices and palisade veins had disappeared from color flow images. In conclusion, ECDUS was useful for evaluating hemodynamic changes after EIS.  相似文献   
967.
We report a 45-year-old woman with iron deficient anemia (IDA) who underwent a collection of allogeneic peripheral blood stem cells (PBSCs) induced by granulocyte-colony stimulating factor (G-CSF) after a rapid improvement of IDA by iron replacement. Her peripheral red blood cells (RBCs) after iron therapy were composed of two different-sized subpopulations; one consisted of microcytes, which were iron deficient RBCs, and another of normocytes, which were produced after iron replacement. On the first day of PBSC collection, the interface setting was maintained aiming at 2% hematocrit as usual; however, PBSCs could not be collected adequately. Sedimentation of iron deficient, lighter RBCs under centrifugation within a blood cell separator could be similar to that of mononuclear cells, and the lighter RBCs could contaminate the mononuclear cell layer, resulting in the collection of the lighter layers of mononuclear cells than desired. On the second day, we succeeded in obtaining enough PBSCs by collecting heavier layers than those collected on the first day by using a 4% hematocrit and monitoring white blood cell counts of the collection line serially. It should be noted that the lighter RBCs from a donor with a history of IDA could complicate collection of PBSCs.  相似文献   
968.
Chitosan-graft-polyethylenimine as a gene carrier.   总被引:16,自引:0,他引:16  
Chitosans have been proposed as biocompatible alternative cationic polymers that are suitable for non-viral delivery. However, the transfection efficiency of chitosan-DNA nanoparticles is still very low. To improve transfection efficiency, we prepared chitosan-graft-polyethylenimine (CHI-g-PEI) copolymer by an imine reaction between periodate-oxidized chitosan and polyethylenimine (PEI). The molecular weight and composition of the CHI-g-PEI copolymer were characterized, using multi-angle laser scattering (GPC-MALS) and (1)H nuclear magnetic resonance ((1)H NMR), respectively. The copolymer was complexed with plasmid DNA (pDNA) in various copolymer/DNA (N/P) charge ratios, and the complex was characterized. CHI-g-PEI showed good DNA binding ability and high protection of DNA from nuclease attack. Also, with an increase in charge ratio, the sizes of the CHI-g-PEI/DNA complex showed a tendency to decrease, whereas the zeta potential of the complex showed an increase. The CHI-g-PEI copolymer had low cytotoxicity, compared to PEI 25K from cytotoxicity assays. At high N/P ratios, the CHI-g-PEI/DNA complex showed higher transfection efficiency than PEI 25K in HeLa, 293T and HepG2 cell lines. Our results indicate that the CHI-g-PEI copolymer has potential as a gene carrier in vitro.  相似文献   
969.
Group A streptococcal (GAS) tonsillopharyngitis is one of the few conditions for which antibiotics are advocated among common upper respiratory infections. Although a 3-day course of azithromycin is attracting attention as a treatment of choice for the condition, it is not clear if the efficacy of the treatment is comparable with that of treatment with cephalosporins. A prospective, randomized, comparative multicenter study was conducted to compare the efficacy of azithromycin (AZM) given once daily for 3 days with that of cefcapene-pivoxyl (CFPN-PI) divided into three daily doses for 5 days. 88 patients (male: 38, mean age: 16.5) were treated with AZM and 69 (male: 34, mean age: 16.9) with CFPN-PI. The symptoms of all but 5 (2 for AZM and 3 for CFPN-PI) of the patients were resolved by the 8th day of the treatment. By the 4th day of the treatment, criteria for clinical efficacy were fulfilled in 71 (80.7%) subjects who were treated with AZM and in 48 (67.6%) of those treated with CFPN-PI (p = 0.07). The same figures on the 8th day of the treatment were 86 (97.7%) and 68 (95.8%), respectively (p = 0.66), confirming there was no significant difference in clinical efficacy between the two treatments. Mild adverse reactions were reported by two patients treated with AZM and by none treated with CFPN-PI. The clinical efficacy of a 3-day course with AZM was comparable with that of a 5-day course of CFPN-PI for GAS tonsillopharyngitis.  相似文献   
970.
Several treatments for coronary artery disease have been developed. Current techniques for both coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) have improved the outcomes after procedures. However, patients referred for CABG have been changing because of the recent advancement of PCI. The number of patients referred for CABG has decreased; furthermore, those patients have significant comorbid conditions and multiple severe coronary artery disease. Several randomized controlled clinical trials demonstrated the superiority of CABG regarding major adverse cardiac and cerebral events to PCI. The selection of these two invasive therapies including hybrid approach should be done by both patients' clinical condition and anatomical characteristics of coronary artery.  相似文献   
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