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71.
The clinical usefulness of FDG-PET in the prediction and assessment of response to radiation therapy in patients with bronchogenic carcinoma was evaluated. Thirty patients with untreated bronchogenic carcinoma were included in the study. All patients received FDG-PET before the initiation of radiation therapy, while 20 also received it after completing the therapy. The tumor to muscle ratio (TMR) was used as an index of the FDG uptake. The tumor response to therapy was classified as either a partial response (PR, n = 21) or no change (NC, n = 9) according to changes in the tumor size. Prognosis was made 6 months after the initiation of therapy, and was classified as either relapse (n = 19) or non-relapse (n = 9). The FDG uptakes both before and after therapy were compared with tumor response and prognosis. A high FDG uptake was noted in all 30 lesions before therapy. No significant differences in the uptake before therapy was observed according to the histological types nor T factors (UICC). The lesions with a higher uptake (TMR more than 7) responded better to therapy than those with a lower uptake (p < 0.05). The decrease in the uptake after therapy tended to be more prominent in the PR group than in the NC group. The rate of relapse was higher in lesions with a higher uptake before therapy (TMR more than 10) than in those with a lower uptake. The relapse group also showed a higher uptake after therapy than the non-relapse group. In addition, all 6 lesions showing a higher uptake (TMR more than 5) after therapy eventually relapsed (p < 0.05). Two lesions demonstrating a lower uptake both before and after therapy did not relapse, although no tumor regression due to the therapy was observed. These results indicate that FDG-PET plays a complementary role in both predicting and assessing the therapeutic response and prognosis in patients with bronchogenic carcinoma.  相似文献   
72.
In recent years, a large number of clandestinely produced controlled-substance analogs (designer drugs) of amphetamine with high structural variety have been detected in forensic samples. Analytical differentiation of regioisomers is a significant issue in forensic drug analysis because, in most cases, legal controls are placed only on one or two of the three isomers. In this study, we used gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the differentiation of regioisomers of fluoroamphetamine analogs (fluoroamphetamines and fluoromethamphetamines), which were synthesized in our laboratories. Free bases and their acylated and silylated derivatives were subjected to GC–MS analysis using DB-1ms, DB-5ms, and DB-17ms capillary columns. The separation of free bases was incomplete on all columns. Trifluoroacetyl derivatives of 3- and 4-positional isomers showed slight separation on DB-1ms and DB-5ms. On the other hand, trimethylsilyl derivatization enabled baseline separation of six fluoroamphetamine analogs on DB-1ms and DB-5ms columns, which was sufficient for unequivocal identification. For LC–MS/MS, a pentafluorophenyl column was able to separate six regioisomeric fluoroamphetamine analogs but a conventional C18 column could not achieve separation between 3- and 4-positional isomers. These results show that a suitable choice of derivatization and analytical columns allows the differentiation of regioisomeric fluoroamphetamine analogs.  相似文献   
73.
The aim of the present study was to ascertain the role of social support and individual styles of coping on employee well‐being. The subjects were intermediate managers working for a zipper and sash manufacturing company in Japan. Measurements were made of the following: depression using the Self‐rating Depression Scale (SDS), job demand, job control, social support using Karasek's Job Content Questionnaire, and of three coping styles: emotion‐oriented coping, task‐oriented coping and avoidance‐oriented coping using the Coping Inventory for Stressful Situations (CISS). Data was analysed by structural equation modeling. Each coping style had a direct effect on depression. Emotion‐oriented coping had a negative effect. On the other hand, task‐oriented coping and avoidance‐oriented coping had a positive effect. Moreover, there was an indirect effect that coping styles precede and determine the perception of social support as well as job demand and control. Social support showed a direct positive effect on depression. However, the overall impact on employee well‐being was greater for individual coping styles as compared to social support from either supervisors or co‐workers. The present study showed the effectiveness of coping strategies in the workplace. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
74.
Anterior mediastinal hemangiomas are very rare neoplasms in mediastinal tumors. A 58-year-old woman was revealed to have a mass measuring 4×3 cm in size in the anterior mediastinum with calcification on computed tomography. It was initially suspected to be a thymoma. We performed tumor extirpation in November 1998. The tumor was close to the thymus and slightly adhered to the superior vena cava, ascending aorta and right phrenic nerve, however, it did not invade any surrounding organs. Histopathologically, it was diagnosed to be a venous type hemangioma composed of vessels covered by smooth muscle and a cavernous type hemangioma composed of dilated vessels covered by one layer of endothelial cells.  相似文献   
75.
We investigated the possibility of using computer analysis of high-resolution CT images to radiologically classify the shape of pulmonary nodules. From a total of 107 HRCT images of solid, solitary pulmonary nodules with prior differentiation as benign (n=55) or malignant (n=52), we extracted the desired pulmonary nodules and calculated two quantitative parameters for characterizing nodules: circularity and second central moment. Using discriminant analysis for two thresholds in differentiating malignant from benign states resulted in a sensitivity of 76.9%, a specificity of 80%, a positive predictive value of 78.4%, and a negative predictive value of 78.6%.  相似文献   
76.
We report a case of bilateral breast cancer lesions treated successfully by partial oncoplastic surgery. A 46-year-old Japanese woman presented with a small mass in the right breast. Mammography showed neither a mass nor calcification in the right breast; however, an irregular-shaped mass lesion was shown in the left breast. Ultrasonography and fine-needle aspiration biopsy revealed ductal carcinoma in situ in the inner-upper quadrant of the right breast and invasive ductal carcinoma in the outer-upper quadrant of the left breast. We considered that it would be difficult to obtain a good symmetrical outcome after partial mastectomy for the bilateral breast lesions because of the asymmetrical location of each lesion and her ptotic breasts. Thus, we performed bilateral partial resection, followed by an inferior pedicle reduction mammaplasty-type operation, with and without axillary lymphadenectomy, and achieved good cosmetic and oncologic results.  相似文献   
77.
To our knowledge, only a few cases of thyroid carcinoma with an extensive tumor thrombus in the atrium have been reported in literature. We describe a unique case of papillary carcinoma of the thyroid with extensive tumor thrombus in the atrium. A 74-year-old man consulted our hospital because of thyroid carcinoma with an extensive tumor thrombus in the atrium. Computed tomography (CT) revealed a 2-cm tumor with extensive continuous tumor thrombus in the left jugular vein, innominate vein, superior vena cava, and atrium. The tumor was resected to reduce the risk of sudden death from tumor embolism into the pulmonary arteries. Histologically, the diagnosis was papillary carcinoma of the thyroid. Thyroid carcinoma, especially papillary carcinoma, rarely develops a macroscopic tumor thrombus. Patients with an extensive tumor thrombus generally have poor prognoses and high mortality. This patient has been followed for 7 months after successful operation without recurrence.  相似文献   
78.
Background  Sentinel nodes (SNs) are the lymph nodes that directly receive lymphatic flow from a primary cancer lesion. The SN concept implies that lymphatic metastasis initially occurs at SNs. SN navigation surgery can be introduced for cancers in which the SN concept is established. In SN navigation surgery, lymph node dissection beyond SNs can be omitted if SNs are metastasis free. Although the SN concept has been investigated frequently for oral and oropharyngeal cancer, it has so far been investigated less for laryngeal and hypopharyngeal cancer. In this study, we investigated whether the SN concept is applicable for laryngeal and hypopharyngeal cancer. Methods  Twenty patients with T2–T4 and clinically N0 laryngeal and hypopharyngeal cancer were recruited. 99mTc-phytate was injected into several sites surrounding the tumor on the day before surgery. Lymphoscintigrams were acquired from at least two different viewpoints. SNs were surveyed intraoperatively, and neck dissections including at least levels II, III, and IV were performed. Results  SNs had occult metastases in five cases. In the remaining 15 cases, neither SNs nor other lymph nodes contained metastases, consistent with the SN concept. There was one false-negative case showing delayed nodal metastasis 2 years after initial surgery. The overall accuracy of the SN concept was 95%. Conclusion  Our study shows that SN biopsy is a reliable strategy to determine correct lymph node status in N0 laryngeal and hypopharyngeal cancer. SN detection was valuable in evaluating the need for neck dissection, whether ipsilaterally or bilaterally. Presented at the 2004 Annual Meeting of the American Academy of Otolaryngology, New York.  相似文献   
79.
Purpose The relationship between the prognosis and the extent of colorectal carcinoma (CRC) is still unclear. As a simple parameter of the local invasion of CRC, we assessed the extent of tumor invasion beyond the outer border of the muscularis propria (MP). Methods We examined 147 cases of CRC using a slight modification of the procedure established by the Japanese Society for Cancer of the Colon and Rectum. For the statistical analysis, the patients were divided into two groups, namely, a “shallow” group and a “deep” group, using a specific cut-off value (COV). A multivariate analysis to identify independent prognostic factors was performed. Results Significant differences in the 5-year survival rate were observed between the “shallow” and “deep” groups in 39 cases of rectal carcinoma (COV 4 mm; 72.4% vs. 30.0%, hazard ratio = 3.204), but not observed in 147 cases of CRC. In addition, the outcome for patients with “deep” cancer in the lower rectum was markedly worse than that for patients with “shallow” cancer (COV 4 mm; 81.8% vs. 12.5%, hazard ratio = 5.371). Conclusions The depth of tumor invasion beyond the MP is thus considered to be an important prognostic factor for patients with T3/T4 rectal carcinoma, especially in the lower rectum. A careful follow-up is required for the patients with rectal carcinoma that has invaded more than 4 mm beyond the MP.  相似文献   
80.
BACKGROUND: Although membranous nephropathy is a common cause of nephrotic syndrome in adults, its treatment remains under debate. METHODS: To clarify the effects of steroid therapy, the data of 51 Japanese adult patients with idiopathic membranous nephropathy who received treatment at our department were analyzed retrospectively. We divided the patients with nephrotic syndrome and a serum creatinine level <1.7 mg/dL, into two groups: the steroid therapy group (n=20) and the non-steroid therapy group (n=7), and compared the clinical characteristics between the two groups. RESULTS: Significantly decreased proteinuria levels (p<0.05) after 2 and 5 years were observed in the steroid therapy group as compared to the non-steroid therapy group. There was no significant difference in the serum creatinine levels after 2 and 5 years between the steroid therapy group and the non-steroid therapy group. CONCLUSION: Steroid therapy in idiopathic membranous nephropathy showed good efficacy in patients with nephrotic syndrome.  相似文献   
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