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PURPOSE: Recent studies reported that clinical responsiveness to gefitinib was associated with somatic mutation of epidermal growth factor receptor (EGFR) gene in non-small cell lung cancers (NSCLC). Here, we investigated the relationship between EGFR mutation and clinicopathologic features. EXPERIMENTAL DESIGN: EGFR mutational status of 120 NSCLCs was determined mainly in EGFR exons 18 to 21 by direct sequence and correlated with clinicopathologic parameters. RESULTS: EGFR mutations were present in 38 cases (32%) and the majority of mutations were in-frame deletions of exon 19 (19 cases) and a missense mutation in exon 21 (18 cases). EGFR mutations were frequently associated with adenocarcinoma (P < 0.0001), never smoker (P < 0.0001), and female gender (P = 0.0001). Of interest, increasing smoke exposure was inversely related to the rate of EGFR mutation (P < 0.0001). Multivariate analysis showed that smoking and histology were independent variables. Furthermore, gender difference was observed for the mutational location (P = 0.01) dominance of exon 19 for males and exon 21 for females. Twenty-one cases were treated with gefitinib and found that EGFR mutation was significantly related to gefitinib responsiveness (P = 0.002). In addition, median survival times of patients with and without EGFR mutations treated with gefitinib were 25.1 and 14.0 months, respectively. Patients with EGFR mutations had approximately 2-fold survival advantage; however, the difference was not significant. CONCLUSIONS: We show that EGFR mutations were significantly related to histology and smoke exposure and were a strong predictive factor for gefitinib responsiveness in NSCLC.  相似文献   
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Fatigue is a common complaint among medical students and researchers consider it to be related to poor academic outcomes. The authors' goal in the present study was to determine whether stress and coping strategies were associated with fatigue in medical students. The study group consisted of 73 second-year healthy students attending the Osaka City University Graduate School of Medicine. Participants completed a questionnaire about fatigue (Japanese version of Chalder Fatigue Scale), stress, stress coping (Japanese version of the Coping Inventory for Stressful Situations), overwork, and nocturnal sleeping hours. On univariate and multivariate logistic regression analyses adjusted for age and gender, stress was positively associated with fatigue. In addition, after adjustment for age, gender, and emotion- and task-oriented stress coping activities, avoidance-oriented stress coping activity was associated with fatigue. The results suggest that stress and the coping style are correlated with fatigue in medical students.  相似文献   
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A subcutaneous tumor accompanied by tenderness has a myriad of differential diagnoses. Indeed, using physical findings alone to achieve a diagnosis is often challenging. In this study, we focused on schwannomas and angioleiomyomas, which usually develop as hard subcutaneous tumors and are often associated with tenderness. We aimed to determine significant differentiating features between the tumor types, using ultrasonography. We compared clinical findings and ultrasonographic imaging and calculated the statistical significance for each item. In total, we analyzed 11 schwannomas and 13 angioleiomyomas of the extremities, trunk and head. There was no significant difference in patient characteristics or clinical findings. Meanwhile, the mean maximum diameter (P = 0.002), localization (P = 0.04) and entering or exiting nerves (P = 0.01) were significantly different according to ultrasonography findings. Thus, ultrasonography provides excellent information for the initial assessment of a slow‐growing, painful, subcutaneous soft tissue mass. According to our study, it is difficult to identify a single, differentiating feature between angioleiomyoma and schwannoma on ultrasonography, but including multiple findings during the work‐up can facilitate differential diagnosis.  相似文献   
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Laparoscopic wedge resection (LWR) for intraluminal gastrointestinal stromal tumor (GIST) leads to excessive resection of normal gastric wall. We report a case of GIST around the cardia successfully treated with full-thickness partial resection using a hybrid approach of laparoscopic surgery and single-incision intragastric surgery (SIIGS). A 69-year-old woman had a 5 cm intraluminal GIST at the posterior wall around the cardia. Submucosal injection of glycerin and indigo carmine was performed with transoral endoscopy. Circumferential seromuscular incision followed by placement of seromuscular sutures to invert the lesion into the stomach was performed under laparoscopy. By SIIGS, resection of the inverted mucosa and retrieval of the tumor were completed. A hybrid approach consisting of laparoscopic wall-inversion surgery and SIIGS was useful for intraluminal GIST and may expand the indications for laparoscopic wall-inversion surgery by removing size limitations.  相似文献   
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Abstract

This study aimed to characterize the effect of different running modes on serum irisin concentrations in rats. A total of 18, 10-week-old rats were divided into three groups; control group, 16° uphill running group (concentric exercise; CON) and, ?16° downhill running group (eccentric exercise; ECC). The running group’s rats ran on the inclined treadmill at 16?m/min, for a total of 90?min. Blood was drawn from the rats, 48?h after running, after which the rats were anesthetized. The serum concentrations of irisin were measured using enzyme-linked immunosorbent assays. Vastus intermedius was collected for immunohistochemical analysis. After multiple comparisons, the ECC showed a significantly high serum irisin concentration (ECC: 28.42?±?6.31?ng/ml, CON: 21.27?±?3.03?ng/ml) and a larger irisin antibody reactive cross-sectional area in vastus intermedius compared to the CON (p?<?0.05). This is the first study to reveal that single bout downhill running increases serum irisin concentrations in rats.  相似文献   
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