Yutaka Yoshii

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This paper describes circuit design and measurement results of a pure HBT MMIC power amplifier module (PA) operating with a 2.5-V low reference (Vref) and 2.8-V low collector supply voltages (Vcc). While covering 824-925-MHz broadband CDMA operation at 2.8-V Vcc, the PA allows a 1.1-V low Vcc and 18-dBm Pout operation. This is realized by an on-chip step(More)
Cigarette smoke (CS)-induced cellular senescence has been implicated in the pathogenesis of chronic obstructive pulmonary disease, and SIRT6, a histone deacetylase, antagonizes this senescence, presumably through the attenuation of insulin-like growth factor (IGF)-Akt signaling. Autophagy controls cellular senescence by eliminating damaged cellular(More)
Mitochondria are dynamic organelles that continuously change their shape through fission and fusion. Disruption of mitochondrial dynamics is involved in disease pathology through excessive reactive oxygen species (ROS) production. Accelerated cellular senescence resulting from cigarette smoke exposure with excessive ROS production has been implicated in the(More)
A 17-year-old-man developed left-sided pneumothorax in 1995. Chest computed tomography (CT) showed a thick-walled cavity in the left lower lobe. Video-assisted thoracic surgery was performed, and pathologic findings of the resected lung showed a cavity, organizing hematoma, and a fibrous nodule. Fragility of connective tissue was suspected, and biochemical(More)
The aim of the current study was to investigate the lethal complications of Legionella pneumonia. Severe complications and their outcomes in 65 patients with Legionella pneumonia were studied. All patients who eventually had a fatal outcome or who had severe complications received antimicrobial agents active against Legionella on the admission day. Many(More)
We encountered a 59-year-old man, whose chief complaints were sputum and dyspnea on effort. He had suffered from sinusitis since childhood, and chest computed tomography showed bronchiectasis. Electron microscopic examination of bronchial mucosa biopsied by bronchoscopy showed defect of the inner dynein arm in most of his cilia. We diagnosed primary ciliary(More)
We encountered a case of limited-disease small cell lung cancer with episodic syncope. The frequency of the syncopal attacks increased with the increase in the tumor size, thus a relationship was suspected to exist between the SCLC and syncope. Syncope was evaluated by history taking, 24-hour ECG monitoring, and coronary angiography. As orthostatic(More)
We have demonstrated the single-chip RF front-end GaAs MMIC for the Japanese Personal Handy-phone System. It has a high efficiency HPA, a T/R switch, a LNA and a low-distortion down converter mixer. The IC employs a negative voltage generator for use of single voltage DC power supply. The HPA provides an output power of 21.5 dBm, with an ACPR of −55 dBc and(More)
Respiratory infection is a major cause of exacerbation in chronic obstructive pulmonary disease (COPD). Infectious contributions to exacerbations remain incompletely described. We therefore analyzed respiratory tract samples by comprehensive real-time polymerase chain reaction (PCR) in combination with conventional methods. We evaluated multiple risk(More)
We report the case of a 75-year-old woman with mucoid impaction of the bronchi (MIB) due to Schizophyllum commune who improved with itraconazole (ITCZ) administration and relapsed after discontinuation of the drug. She improved again after readministration of ITCZ, and MIB has not recurred. This patient was not suffering from asthma and has been well(More)