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1.
Benign noninflammatory bronchial stenosis: treatment with balloon dilation   总被引:11,自引:0,他引:11  
  相似文献   
2.
A patient known with acute intermittent porphyria who developed primary liver-cell carcinoma is described. No other risk factors were found. A possible association of acute intermittent porphyria with the development of primary liver-cell carcinoma has been suggested in recent, mainly Scandinavian literature. So far this association has never been described in The Netherlands.  相似文献   
3.
Bronchopulmonary carcinoid tumors are tumors with a low malignant potential. They metastasize in 5-15% of cases. Accurate histologic preoperative prediction of the presence of regional lymph node metastases is not possible at this time. A retrospective quantitative pathologic analysis was performed to investigate the possibility of predicting the presence or absence of regional lymph node metastases in 24 patients with bronchopulmonary carcinoid tumors. The results of univariate analysis showed that large tumor size was associated significantly more frequently with regional lymph node metastases than small tumor size (P less than 0.01). The other quantitative features, ie, a larger mean nuclear area, higher standard deviation of the nuclear area and the presence of an aneuploid DNA index, were frequently associated with regional lymph node metastases, but this tendency was not significant. In multivariate analysis the combination of tumor size and mean nuclear area predicted the presence or absence of regional lymph node metastases correctly in 80 and 94% of the cases, respectively. These results indicate that the combination of tumor size and mean nuclear area may serve as a guideline to predict the presence of regional lymph node metastases.  相似文献   
4.
Pulmonary atypical carcinoid: predictors of survival in 106 cases   总被引:5,自引:0,他引:5  
Pulmonary neuroendocrine tumors (NE) include a spectrum of tumors from typical carcinoid (TC) to atypical carcinoid (AC), large cell neuroendocrine carcinoma (LCNEC), and small cell carcinoma (SCLC). Little is known about prognostic predictors for AC because of its rarity. Survival analysis was performed on 106 ACs with clinical follow-up from the AFIP and the Pathology Panel of the International Association for the Study of Lung Cancer (IASLC). The tumors fulfilled the 1999 WHO/IASLC criteria for AC of a NE tumor with a mitotic rate of 2 to 10 per 2 mm(2) of viable tumor or coagulative necrosis. Multiple clinical and histologic features were analyzed by Kaplan-Meier and Cox regression analysis. Of the clinical features, higher stage (P = .003) and a tumor size of 3.5 cm or greater (P = .003) were associated with a worse prognosis. Features that were histologically unfavorable by univariate analysis were mitotic rate (P =.002), pleomorphism (P = .018), and aerogenous spread (P =.007). Histologically favorable features by univariate analysis were the presence of palisading (P = .008), papillary (P = .039), pseudoglandular (P =.026), and rosette (P = .022) patterns. Female gender showed a trend toward a poorer prognosis (P =.085) and was included in the multivariate model. Multivariate analysis stratified for stage showed mitoses (P<.001), a tumor size of 3.5 cm or greater (P =.017), and female gender (P =.012) to be the only negative independent predictors of prognosis and the presence of rosettes (P = .016) to be the only independent positive predictor. We further divided the AC into subgroups of low (2 to 5 mitoses/2 mm(2)) and high (6 to 10 mitoses/2 mm(2)) mitotic rate and compared the survival with TC and with LCNEC. Within the category of AC, the patients with a higher mitotic rate had a significantly worse survival than those with a lower mitotic rate (P<.001) stratified for stage. Five- and 10-year survival rates for AC (61% and 35%, respectively) stratified for stage were significantly worse than for TC and better than that for LCNEC and SCLC. Chemotherapy or radiation therapy was given in 12 of 52 and 14 of 52 cases, respectively, but the data were insufficient to evaluate tumor response. We conclude that AC is an aggressive neuroendocrine neoplasm with survival intermediate between TC and LCNEC and SCLC. Higher mitotic rate, tumor size of 3.5 cm or greater, female gender, and presence of rosettes are the only independent predictors of survival. Surgical resection remains the treatment of choice, and the role of chemotherapy and radiation therapy remains to be proven.  相似文献   
5.
Quantitative DNA analysis has often been proposed as a potential tool capable of detecting preneoplastic tissue and as such to function as an intermediate endpoint in cancer chemoprevention trials. The first aim of this study was to test whether cytomorphometric parameters could be used to detect field cancerization characteristics in cytological preparations of oral mucosa. Cytomorphometric parameters in exfoliated cells of apparently normal oral mucosa of head and neck cancer patients were compared with those of healthy controls. The second aim was to assess the value of these parameters subsequently as intermediate endpoint biomarkers in the mucosa of 70 patients receiving N-acetylcysteine and/or retinyl-palmitate as chemopreventive drugs. No differences were detected between 'high risk' and healthy mucosa, nor were differences observed before and after treatment.  相似文献   
6.
The authors describe a 3-day-old newborn admitted with signs of intestinal obstruction caused by solitary intestinal fibromatosis (SIF). This is a very rare lesion, which has an excellent prognosis. The differential diagnosis of bilious vomiting in a neonate caused by other than tumorous processes in the neonatal intestine is extensive. Probably this kind of lesion is more frequent in the neonatal period than thought until now but underdiagnosed because of the difficulty of diagnosis. Therapy of choice is wide local excision, and prognosis is excellent.  相似文献   
7.
BACKGROUND: In this study, the potential impact of a new national guideline for adjuvant systemic therapy in breast cancer (introduced in The Netherlands in 1998) was assessed, as well as the modifications of this guideline, issued in 2001. Both the change in total number of patients eligible for adjuvant therapy, as well as the cost-effectiveness of the changed clinical management of these patients were analysed. PATIENTS AND METHODS: Percentages of patients who would be eligible for adjuvant therapy in 1994, 1998 and 2001 were estimated, based on clinical data from 127 patients, who were operated on in 1994. Ten-year overall survival rates were used as a measure of effectiveness, based on the two most recent EBCTCG meta-analyses. Actual resource costs were calculated. With a decision analytic model, the incremental cost-effectiveness ratios (1998 versus 1994, and 2001 versus 1998) were calculated. RESULTS: The introduction of the 1998 guideline resulted in a relative increase of 80% in the total number of patients eligible for adjuvant therapy, compared with 1994 (from 40% to 72% of all patients with primary breast cancer). With an estimated absolute increase of 10-year overall survival of 2%, the 1998 guideline was found to have an expected incremental cost-effectiveness ratio of about 4837 per life-year gained. CONCLUSIONS: Introduction of the new guideline considerably affected the number of patients eligible for adjuvant systemic therapy for breast cancer. The associated incremental cost-effectiveness ratio is well within the range of values that are generally considered acceptable.  相似文献   
8.
McGee  MP; Wallin  R; Wheeler  FB; Rothberger  H 《Blood》1989,74(5):1583-1590
We examined assembly and expression of the factor X activating complex on human and rabbit alveolar macrophages. Kinetic parameters of the factor X activating reaction were determined by functional titrations of factors VII and X with macrophage tissue factor (TF) added. We found rapid activation of factor X to Xa on alveolar macrophage surfaces. Detection of rapid factor Xa formation on macrophages required addition of exogenous factors VII and X. At plasma concentrations of the purified factors, factor Xa was formed on freshly isolated macrophages at approximately 5.4 pmol/min/10(6) cells. After macrophage maturation in culture for 20 hours with LPS (endotoxin) added, the factor X activation rate was increased two- to sixfold. The km' (apparent km) of TF-factor VII enzymatic complexes assembled on alveolar macrophages for factor X were (258 +/- 55 and 475 +/- 264 nmol/L for human and rabbit cells, respectively). The km' did not change during macrophage maturation in culture, but V'max (apparent Vmax) was consistently increased. The K1/2 of human factor VII (concentrations giving half maximal rates of factor X activation) for the interaction with human and rabbit alveolar macrophage TF were 0.191 +/- 0.096 and 1.7 +/- 0.7 etamol/L, respectively. The K1/2 were not significantly changed after maturation, whereas rates of Xa formation at saturation with factor VII were increased. The fast rates of factor X activation observed at physiologic concentrations of plasma-derived factors VII and X indicate that TF on alveolar macrophages is likely to provide sites for binding of factor VII and activation of factor X in vivo during clotting reactions associated with alveolar edema and inflammation.  相似文献   
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