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Guided bronchoscopy has been found to be useful for the diagnosis of solid peripheral pulmonary lesions (PPLs) but more evidence on ground glass opacities (GGOs), especially those without a solid component, are lacking. A 69-year-old male, asymptomatic, heavy smoker was referred to our department for non-surgical diagnosis of a focal pure GGO in the right upper lobe that was found incidentally on computed tomography (CT). Transbronchial biopsy (TBB) with the aide of endobronchial ultrasound with a guide sheath (EBUS-GS), virtual bronchoscopic navigation (VBN), and fluoroscopy was performed for sampling. There were no complications after the procedure. The diagnosis of adenocarcinoma with lepidic growth pattern was established from the fourth and fifth TBB specimens and was confirmed on subsequent surgical resection. Image-guided bronchoscopy with TBB was successful for the diagnosis of a pure GGO. Use of a larger biopsy device may be helpful for the histopathologic diagnosis of lung adenocarcinoma with lepidic growth.  相似文献   
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18O‐labeled water (Water‐18O) is a widely used starting material of 18F‐labeled diagnostic agents in positron emission tomography (PET). Conventionally, Water‐18O has been separated from other stable oxygen isotope species (16O, 17O) by water distillation or nitric oxide distillation. However, conventional methods are costly and may have safety issues. In 2004, we developed the first unit of our novel oxygen isotope separation process by cryogenic oxygen distillation to overcome these issues. To meet the needs of the market, we built a second unit in 2013 and a third in 2016. We are now operating three commercially viable separation units with a total capacity of 600 kg of Water‐18O per year.  相似文献   
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Background/Aims: Few studies exist on the efficacy and long-term outcome of radiation therapy (RT) for gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Methods: Twenty-two patients with stage I or stage II(1) disease were prospectively evaluated, including 14 patients without Helicobacter pylori(H. pylori) infection and 8 patients with persistent lymphoma after H. pylori eradication. RT dose was 30 Gy in daily fractions of 1.5 Gy. All patients underwent endoscopic and histological follow-up regularly. Results: The study included 22 patients with a mean age of 63 years. The t(11;18)(q21;q21) translocation occurred in 8 of the 22 cases. All patients showed complete remission without any serious toxicity. At a median follow-up evaluation 74 months (range 27-159) after completion of RT, the overall and relapse-free survival rates after 5 years were 91 and 84%, respectively. Although no patient showed local recurrence of lymphoma, distant recurrence was detected in 3 patients, all of whom were H. pylori negative; MALT lymphoma relapsed in two patients with the t(11;18)(q21;q21) translocation, and diffuse large-cell lymphoma developed in one patient without the translocation. Conclusion: RT provides excellent local control of the gastric MALT lymphoma. However, continuous follow-up is mandatory as relapse may occur in other sites.  相似文献   
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Neuroendocrine carcinoma (NEC) of the stomach is an uncommon disease. Because of its rarity, the clinicopathological features are unclear, and there is no consensus on the optimal treatment strategy. This study included five consecutive patients with gastric NEC who underwent surgery from July 2001 to August 2011. Clinical presentation, tumor location, tumor morphology and size, pathology and immunohistochemistry results, and treatment outcome were analyzed retrospectively and discussed. The study cohort of four men and one woman ranged in age from 52 to 84 years, with a median age of 72 years. Positive rates of neuroendocrine markers were 40 % for chromogranin A, 60 % for synaptophysin, 60 % for CD56, 40 % for neuron-specific enolase, and 100 % for p53 protein. Median number of lymph node metastases per patient was 10, with severe lymphatic and venous infiltration, and high Ki-67 labeling index (60–90 %) reported for all patients. Median tumor size was 6 cm. Stage IV disease was diagnosed in three patients; the other two patients showed stage IIIA tumors. After a mean follow-up of 29.8 months, two of the five patients had died of the disease. Although rare, gastric NECs deserve particular attention because of their strong malignant potential associated with an extremely poor prognosis. Such carcinomas demand an aggressive surgical approach followed by chemotherapy and multimodality adjuvant therapy.  相似文献   
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Background: Previous studies have described the clinical usefulness of the presence of nonsustained ventricular tachycardia (NSVT) and defined heart rate turbulence (HRT) in stratifying patients at risk. We prospectively assessed whether HRT can facilitate the predictive accuracy of NSVT for identifying patients at risk for serious arrhythmic events in patients with left ventricular (LV) dysfunction. Methods: We enrolled 299 consecutive patients with LV dysfunction (ejection fraction ≤ 40%) including ischemic (n = 184) and nonischemic causes (n = 115). The presence of NSVT was assessed on Holter electrocardiograms (ECGs). HRT was simultaneously measured from Holter ECGs, assessing two parameters: turbulence onset (TO) and turbulence slope (TS). HRT was considered positive when both TO and TS were abnormal. The end point was defined as of sudden cardiac death (SCD) and sustained ventricular tachyarrhythmias (VTs). Results: NSVT was documented in 93 patients (32.7%). For HRT assessment, 17 patients (5.6%) were not utilized. Of 282 patients, 68 (24.1%) were HRT positive. During follow‐up of 960 ± 444 days, 14 patients (5.0%) reached the end point. NSVT, HRT, and diabetes were significantly associated with the end point. On multivariate analysis, NSVT had the strongest value for the end point, with an HR of 4.4 (95%CI, 1.4–14.3; P = 0.0138). When NSVT combined with HRT, the predictive accuracy is more increased, with an HR of 8.2 (95%CI, 2.9–23.3; P < 0.0001). The predictive values of the combination were higher than single use of NSVT or HRT. Conclusions: HRT can facilitate the predictive accuracy of NSVT for identifying patients at risk for serious arrhythmic events in patients with LV dysfunction.  相似文献   
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Background and objective: Interstitial lung diseases (ILD) are characterized by progressive interstitial pulmonary fibrosis and a decline in lung function. Fibrocytes are bone marrow‐derived mesenchymal progenitor cells that may play a role in the pathogenesis of pulmonary fibrosis. Circulating fibrocyte numbers have been correlated with the prognosis of patients with idiopathic pulmonary fibrosis. The aim of the present study was to evaluate the relationship between circulating fibrocytes, and parameters of disease activity and progression in several groups of patients with ILD. Methods: The study population comprised 41 patients with ILD and seven healthy control subjects. Circulating CD45+ collagen‐I+ fibrocytes were evaluated by flow cytometry. Results: The number of circulating fibrocytes was significantly increased in all patients with ILD and particularly in patients with idiopathic interstitial pneumonitis and interstitial pneumonitis associated with collagen vascular disease as compared with healthy control subjects. The numbers of circulating fibrocytes were significantly correlated with pulmonary function test parameters and with serum levels of sialylated carbohydrate antigen, a marker of disease activity. Temporal changes in circulating fibrocyte numbers were evaluated in two patients, and the results suggested that these changes correlated with the activity of ILD. Conclusions: The results from this study provide further evidence for the role of circulating fibrocytes in fibrotic lung diseases.  相似文献   
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