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91.
BACKGROUND: The technique of video-assisted thoracic fine-needle aspiration cytology (VAT-FNA) to the lung has been described in very few publications, and its diagnostic role has not been evaluated so far. Thus current studies focus on whether the diagnostic role could be applied usefully to VAT-FNA of peripheral lung lesions. METHODS: Between January 1995 and January 2000, a total of one hundred and twenty-eight cases of VAT-FNA on lung tumors were reviewed retrospectively. The superficial lung was visualized a part of directly or indirectly by scope and a 22-gauge needle inserted for FNA. Material was expressed onto glass slides, and smears were stained by our modified quick-stain method. The cytological diagnoses based on VAT-FNA were reviewed and compared with the final histopathological diagnoses. RESULTS: The cytological diagnosis was true positive in 100 cases (93.5% sensitivity), whereas the true negative result in 20 cases was 95.2% specificity. The false-positive rate was 4.8%, and false-negative results were 6.5%. The accordance in all malignant cases between cytology and histology was 73.8%. VAT-FNA caused no difficulties in any of the cases. CONCLUSION: The application of VAT-FNA to the peripheral lung lesion is not only useful, cost-beneficial, safe and minimally invasive but also accurate. Especially, this method may play an important role in cases of suspected malignancy in peripheral cases.  相似文献   
92.
The incidence of acute pulmonary thromboembolism (APTE) in Japan is quoted as being extremely low compared with the United States, and the incidence and clinical characteristics of chronic pulmonary thromboembolism (CPTE) in Japan is unknown, so this study investigated these aspects of CPTE in 309 patients with APTE and 68 patients with CPTE. The ratio of the incidence of CPTE to APTE was 0.22 and there was no significant difference in age or sex between the APTE and CPTE patients. All of the predisposing factors for pulmonary thromboembolism, except for thrombophilia, were more frequently seen in the patients with APTE. There are some differences in the incidence and clinical characteristics of CPTE compared with APTE between Japanese and American patients in Japan, suggesting that the pathogenesis of CPTE in Japan may differ from that in the USA.  相似文献   
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94.
This study was designed to clarify the mechanism of tolerance that occurs during prolonged administration of a beta-agonist in relation to membrane phospholipid degradation and to elucidate the effect of diltiazem, a calcium antagonist. Guinea pigs were divided into 3 groups: (1) control—physiological saline (0.5 ml) was injected once a day for 7 successive days; (2) metaproterenol (Mp)—Mp was injected intraperitoneally (10 mg/kg/day) for 7 successive days; (3) Mp + diltiazem—diltiazem was injected intraperitoneally (20 mg/kg/day) 30 min before Mp injection for 7 successive days. The number of beta-adrenoceptors and the 10−5 M (−)-isoproterenol-stimulated adenylate cyclase activity were significantly decreased in the metaproterenol group. Diltiazem reduced these decreases. Phospholipase activity was increased and phosphatidylcholine and phosphatidylethanolamine levels were decreased in the metaproterenol group. Diltiazem also reduced these changes. These results suggest that the degradation of membrane phospholipids by phospholipase may be involved in a decrease in beta-adrenergic response caused by successive administration of metaproterenol. Diltiazem protects membrane phospholipids from phospholipase attack, which in turn maintains beta-adrenergic responsiveness. Part of this study was presented at the Annual Meeting of the American Thoracic Society, May 12, 1987, New Orleans, Louisiana  相似文献   
95.
Four kinds of human cancer cell lines and one mouse cancer cell line were inoculated into the subepithelial area of the anorectum of female nude mice. Among the cell lines, two cell lines (KATO III and Lu 135) showed the potential enforcement of atypical changes in the adjacent mouse anorectal epithelium. Moreover, the submucosal invasion of the malignant transformed cells of the mouse epithelium was demonstrated in specimens obtained from three KATO III-inoculated mice. This exciting and novel phenomenon clearly demonstrates the need to change the present general concept of a single-cell origin of cancer tissue. This valuable and novel discovery may change the basis of oncology research while also providing new ideas for projects to investigate the mechanisms of carcinogenesis from several aspects such as molecular biology, cell biology, and pathology. Moreover, the novel experimental design itself is also extremely useful as a simple model for investigating the mechanisms of oncogenesis.  相似文献   
96.
Fibroblast growth factor-2 (FGF-2) has the potential to regenerate damaged articular cartilage tissue due to its exerting anabolic effects on chondrocytes. However, FGF-2 is involved in pathogenesis of rheumatoid arthritis, where the joint is destructed. The study aims at clarifying the effects of FGF-2 on joints. When radiolabeled FGF-2 was injected into knee joints of C57Bl/10 mice, a transient binding was observed in the superficial and intermediate zones of the articular cartilage as well as in the synovium and perichondrium. An FGF-2 injection (5 μg) caused synovial hyperplasia adjacent to the articular cartilage on day 7, cartilage formation adjacent to the articular cartilage on day 14, and osteophyte on day 21. The intensity of safranin-O staining of the articular cartilage increased on day 14. These changes were dose-dependent. No destructive changes in the joints were observed. In a joint, transient exposure of FGF-2 caused proliferative changes, but not destructive changes.  相似文献   
97.
Purpose:The combination of modified Dixon (mDixon) and periodically rotated overlapping parallel lines with enhanced reconstruction sequence with two interleaved echoes, which promotes uniform fat-suppression and motion insensitivity, has recently become available for commercial magnetic resonance imaging (MRI) scanners. To compare the robustness of this combination sequence with that of standard Cartesian mDixon sequence for fat-suppressed T2-weighted imaging in clinical head and neck MRI.Methods:Fifty patients with head and neck tumors were involved this study. All patients underwent MRI using both the combination and standard sequences. Two radiologists independently scored motion artifacts and water–fat separation error using a 4-point scale (1, unacceptable; 4, excellent). Furthermore, comprehensive comparative evaluation was performed using a 5-point scale (1, substantially inferior; 5, substantially superior). Data were statistically analyzed using the Wilcoxon signed-rank test.Results:In the motion artifact assessment, ratings of 3 or 4 points were assigned to 45% (observer-1, 58.0%; observer-2, 32.0%) and 97% (100%; 94.0%) of images for the standard and combination sequences, respectively (P < 0.001). For the water–fat separation error assessment, ratings of 3 or 4 points were assigned to 100% (100%; 100%) and 85% (84.0%; 86.0%) of images, respectively (P < 0.001). In the comprehensive evaluation, of the 100 cases (observer-1, 50; observer-2, 50), 96 were rated at four or five points. In cases with slight or no motion artifacts and water–fat separation errors, the combination sequence was superior to the standard sequence in term of noise and sharpness, and equal in terms of contrast.Conclusion:Although water–fat separation errors increased significantly in the combination sequence, most of these were acceptable. The significantly decreased motion artifacts in the combination sequence significantly improved image quality overall.  相似文献   
98.
Anatomical Science International - Hepatic biliary injury is one of the most common complications in cholecystectomy and is frequently accompanied by arterial injuries. Because there are several...  相似文献   
99.
100.
A 61-year-old woman who had undergone total hysterectomy 16 years previously exhibited a pelvic tumor on computed tomography (CT). F-18 fluorodeoxyglucose (FDG) combined positron emission tomography (PET)/CT imaging revealed a solitary small focus of increased FDG activity in the pelvis. A gastrointestinal stromal tumor originating in the small intestine or another type of tumor originating in the mesentery (desmoid, schwannoma, or foreign body granuloma) was suspected; therefore, laparoscopic resection was conducted. A white, hard tumor was found to originate from the mesentery of the sigmoid colon and adhered slightly to the small intestine. The tumor was resected with a negative margin, and the pathologic diagnosis was suture granuloma. The possibility of suture granuloma should be kept in mind in cases of tumors with positive PET findings and a history of surgery close to the lesion. However, it is difficult to preoperatively diagnose pelvic tumors using a biopsy. Therefore, considering the possibility of malignancy, it is necessary to achieve complete resection without exposing the tumor.Key words: Suture granuloma, Laparoscopy, Positron emission tomography (PET)It is very difficult to diagnose suture granulomas preoperatively. F-18 fluorodeoxyglucose (FDG) combined positron emission tomography (PET)/computed tomography (CT) imaging is often used to differentiate benign from malignant tumors that are difficult to diagnose on other modalities, such as ultrasound (US), CT, and magnetic resonance imaging. However, it is not easy to differentiate tumors associated with inflammation or malignancy using FDG-PET/CT. Suture granulomas are known to be benign; however, false-positive findings were observed on PET/CT in our case. In the literature, there are few reports of suture granulomas showing false-positive findings on PET/CT.15 We report here a case in which it was not possible to rule out the potential for malignancy using CT or FDG-PET/CT and the lesion was confirmed to be a suture granuloma based on a pathologic examination following laparoscopic resection.  相似文献   
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