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BACKGROUND: Mediastinal tumors show a wide variability, and therefore, a standardized diagnostic and therapeutic workup is instrumental. We subdivided mediastinal tumors into nonlymphatic mediastinal tumors (NLMTs), most of which require surgical resection without need of preoperative histology, and mediastinal lymphadenopathy (MLA), requiring surgical biopsy for exact histologic classification. We investigated the accuracy of noninvasive diagnostic studies distinguishing between the two groups of MLA and NLMT. METHODS: A retrospective analysis was performed on patients who had previously undergone surgery on mediastinal tumors. Their data were statistically analyzed (chi2 test, logistic regression analysis), and the values of medical history, physical examination, laboratory tests, and computerized tomography scan discriminating between MLA and NLMT were assessed. RESULTS: Out of 299 patients included in the study, 242 (80.9%) had MLA and 57 (19.1%) had NLMT. Sensitivity and specificity of noninvasive investigations for differentiation of MLA and NLMT were 98.2% and 86.0%, respectively. Whereas the prevalence of thoracic symptoms such as shortness of breath, cough, or chest pain was similar in both groups (MLA, 165 [69.3%]; NLMT, 41 [69.5%]; p = 0.98), systemic symptoms, including fever, night sweats, or weight loss (MLA, 110 [49.8%]; NLMT, 17 [29.3%]; p < 0.01), and signs of inflammation, such as c-reactive protein, erythrocyte sedimentation rate, and leukocytosis (MLA, 202 [85.6%]; NLMT, 34 [57.6%]; p < 0.001), were significantly more common in MLA. CONCLUSIONS: Noninvasive diagnostic procedures, including medical history, physical examination, laboratory tests, and computerized tomographic scan, are highly sensitive in detecting MLAs that should undergo surgical biopsy. Our data suggest confirming all suspected NLMTs by fine needle aspiration (FNA) biopsy before surgery.  相似文献   
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The aim of the present study was to investigate the impact of four different lactobacillus (LB) strains, namely Lactobacillus bulgaricus 291, Streptococcus thermophilus F4, S.thermophilus V3 and Bifidobacterium longum BB536, which are used for the production of yogurt, on the DNA-damaging effects of heterocyclic aromatic amines (HCAs). Male F344 rats were treated orally with HCA mixtures containing 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline, 2-amino-9H-pyrido[2,3-b]indole and 2-amino-3-methyl-3H- imidazo[4,5-f]quinoline, which were representative of the HCA contents found in fried beef ('beef mix') and chicken ('chicken mix'). Suspensions of LB were given by gavage to the animals simultaneously with and at different time periods before administration of the HCAs. Subsequently, the extent of DNA migration was measured in colon and liver cells in single cell gel electrophoresis (SCGE) assays. All four strains caused complete inhibition of DNA damage induced with beef mix after administration of 1 x 1010 LB cells/animal, whereas with chicken mix only marginal (non-significant) effects were seen. The inhibition of beef-induced DNA damage was dose dependent and was still significant when 1 x 107 cells/animal were administered. Kinetics studies showed that the protective effects were still significant when LB was given 12 h before the beef mix. A comparison of the present results with chemical analytical data from in vitro experiments suggests that the strong reduction in DNA migration seen in the animals can be only partly explained by direct binding effects. The results of the present study show that LB are highly protective against the genotoxic effects of HCAs under conditions which are relevant for humans and provide a possible explanation for the reduced colon cancer rates observed in some studies in individuals with either high LB counts in their feces or with a high consumption of LB-containing foods.  相似文献   
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The charts of 431 patients with squamous cell carcinoma of the supraglottic larynx observed at the M. D. Anderson Hospital between January, 1954, and June, 1971, were analyzed. This study is concerned with those patients who had a technically resectable lesion. Emphasis is directed to the analysis of the effectiveness of primary irradiation instead of partial laryngectomy for those lesions which are technically suitable for a partial resection and to define the groups of patients which are best treated by combining surgery and planned postoperative irradiation. One hundred forty-seven patients with T1 and T2 lesions, selected exophytic T3 lesions of the suprahyoid epiglottis and aryepiglottic folds and some selected exophytic T4 lesions of the suprahyoid epiglottis received irradiation for their laryngeal lesion. A satisfactory control of the laryngeal disease has been obtained with preservation of a normal voice ranging from 88.5 percent for T1 lesions to 60 percent for T4 lesions. Comparing the groups of patients who had surgery alone or postoperative irradiation an NED rate of 63 percent was found in the latter group which is clearly superior to the 37 percent found in the surgery only group. There is no difference for the five-year NED rates, because the patients who had surgery and postoperative irradiation had more advanced neck disease which is a cause for distant metastases. The incidence of recurrences above the clavicles is clearly less in the patients having had surgery and postoperative irradiation than in those who had surgery alone. Correlating in the two groups, surgery only and surgery followed by planned irradiation, the surgical staging of the neck metastases with recurrences above the clavicles within 24 months after treatment, it was found that the planned combined treatment has reduced the recurrence rate from 45 percent to 15 percent in the N2 and N3 patients. Postoperative irradiation should be given routinely after resection for all T4 lesions and for any T3 lesion which extends to the pharyngeal wall(s), vallecula, base of tongue, and pyriform sinus. Postoperative irradiation should also be given for any patient whose nodal classification is greater than N1. Irradiation should be given within six weeks (preferably three to four weeks) after the surgical procedure. To achieve this goal, the operation need only remove grossly detectable disease.  相似文献   
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Zusammenfassung Es wurde die Frage untersucht, ob die Aussichten des Eierstockes, der nach Aufbewahrung auf Eis oder bei Zimmertemperatur in ein Wirtstier verpflanzt wird, bezüglich Wurzelfassung und Überleben gesteigert werden, wenn dem Organ vor oder während der Aufbewahrung Wasser entzogen wird.In keiner Versuchsreihe konnten die Aussichten, Wurzel zu fassen und zu überleben, durch unvollkommene Trocknung gesteigert werden.Ein unvollkommen getrockneter Eierstock vermag jedoch noch nach 14tägiger Aufbewahrung auf Eis als Transplantat Wurzel, zu fassen und kann mehr als einen Monat im Wirtstier in follikulärer Entwicklung verharren.Es wäre darum nicht ausgeschlossen, daß unter geeigneteren, noch zu ermittelnden Versuchsbedingungen sich ein fördernder Einfluß der unvollkommenen Trocknung erweisen ließe.Mit 12 Abbildungen im Text.  相似文献   
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