Publications by authors named "Hirofumi Yagi"

The present study elucidated the pathogenesis of allergic symptoms (AS) related to contact lens (CL) wear by assaying CL care solutions in lens storage cases and tears from subjects with AS using molecular biology techniques. A total of 15 CL storage cases were collected from subjects with AS (n=9) and healthy, asymptomatic control CL wearers (n=6). Bacterial populations in CL care solutions and tears were assayed by culture and 16S rDNA sequencing.

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Periodontitis affects oral tissues and induces systemic inflammation, which increases the risk of cardiovascular disease and metabolic syndrome. Subgingival plaque accumulation is a trigger of periodontitis. Fusobacterium nucleatum (FN) contributes to subgingival biofilm complexity by intercalating with early and late bacterial colonizers on tooth surfaces.

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Clostridium perfringens possesses the ethanolamine (EA) utilization (eut) system encoded within the eut operon, which utilizes the EA as a carbon, nitrogen and energy source. To determine the role of the eut system in C. perfringens growth, an in-frame deletion of the eutABC genes was made in strain HN13 to generate the eutABC-deleted mutant strain HY1701.

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The purpose of this study was to discuss the optimal X-ray beam quality for detection of simulated lung nodule on a computed radiography system. We set up four types of X-ray beam quality (90 kV, 120 kV, 150 kV, and 120 kV + gadolinium filter), and kept the incident dose on the patient at 0.3 mGy.

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Although patient exposure has been increasing in recent years, few institutions have dosimeters and are able to ascertain patients' exposure dose. Internationally, however, it is necessary to adopt safety levels for patient exposure doses, and guidance levels have been introduced. Therefore, the need for measurement in areas of x-ray diagnosis has been increasing.

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The half-value layer (HVL) of an X-ray beam for film-screen mammography is considered an important parameter for image quality and patient dose. Thus, HVL must be measured in accordance with The Manual of Accuracy for Mammography printed by the Japanese Society of Radiological Technology. The manual prescribes exactly the geometry of measurement, chamber position of measurement in the field, selection of chamber, and so on.

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Already, the 30 year have passed since that the CT scanner was developed by Hunsfield. And now above 16,000 sets are at work. On the other hand, as the improvements of image reconstruction algorithm and variations os scan method, the medical exposure is increasing.

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Various types of X-ray examinations are currently being carried out for the purpose of diagnosis. However, since dose limits for contamination by medical examinations have not been set, management of dose measurements and contamination records is called for. With increasing use of the IVR technique, reports of radiation injury and the symptoms associated with it have become more common.

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The DBL (MCF-2) proto-oncogene is a prototype guanine nucleotide exchange factor (GEF) that modulates the Rho family of GTPases. In this communication we describe the isolation of three novel splicing variants of Dbl. The prototype Dbl gene (designated var.

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The use of CT has increased rapidly in the past two decades, in part because of the development of helical CT and multidetector row CT. The benefits obtained by CT are not, however, without risks. This paper emphasizes the importance of keeping radiation doses during CT procedures as low as reasonably possible, especially for pediatric and small adult patients.

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