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PURPOSE: To evaluate the therapeutic effectiveness of a combined chemoradiotherapy program, followed by surgery in selected cases, in Stage III non-small cell lung cancer. METHODS AND MATERIALS: Between August 1988 and February 1990, 43 patients Staged IIIa-b (UICC 1987, 58% IIIb) have been treated with concomitant chemotherapy (cisplatin 15 mg/m2 and VP16 75 mg/m2, 5 days a week on week 1 and 5) and radiotherapy (40 Gy split course, 2 Gy/day on week 1, 2, 5, and 6), followed by attempted curative thoracotomy or more cycles of full dose chemotherapy with the same two drugs. RESULTS: Planned chemoradiotherapy has been given to 91% of patients; 13/43 patients have been operated, with 12 complete resections and three (7%) pathological complete responses. Toxicity was significant, with two postoperative deaths and two fatal radiation pneumonitis. Crude progression-free survival rate is 21% at 30 months, with nine patients (21%) alive and free from progression at follow-up times ranging from 31 to 49 months. Subset survival analysis showed a possibly greater therapeutic effect for non-squamous histology as compared to squamous carcinoma. CONCLUSION: These results are encouraging in a cohort of patients with quite advanced disease (58% Stage IIIb).  相似文献   
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Molecular electrostatic potential (MEP) maps of certain 3-methoxy flavone derivatives having different anti-picornavirus activities have been studied. Geometries of the molecules were optimised and charge distributions computed using the AM1 molecular orbital method. Hybridization displacement charges (HDC) were combined with the L?wdin charge distributions to compute the MEP maps. Reliability of the method of computing MEP maps was tested by studying certain other molecules for which ab initio MEP results are available. The anti-picornavirus activities of the flavones have been shown to be related with negative MEP values in two regions, one near the 3-methoxy group and another in a diagonally opposite region near the substituent attached to the C7 atom of the molecules.  相似文献   
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OBJECTIVE: To identify any clinical and pathologic features of treatment modalities that are predictive of outcome in patients with epithelioid sarcoma, a rare slow-growing soft tissue tumor most commonly occurring in the distal extremities of young adults. DESIGN: We reviewed the institutional files for cases of epithelioid sarcoma for the period 1956 to 1991 and analyzed the effect of various factors on survival. MATERIAL AND METHODS: Fifty-five cases of epithelioid sarcoma were found, and the relevant clinical, pathologic, treatment, follow-up, and outcome features were assessed. RESULTS: All tumors were treated initially by operative resection. The recurrence rate progressively decreased with increasing aggressiveness of the initial operation; however, no difference was noted in metastatic rate. Overall, the recurrence rate was 38% and the metastatic rate was 47%. At the end of a mean follow-up of 102 months, 69% of patients had no evidence of disease, 27% had died of the disease, and 4% were alive with disease. Increasing tumor size, necrosis of more than 30%, and vascular invasion correlated significantly with a worse prognosis. CONCLUSION: Epithelioid sarcoma should be considered a malignant neoplasm with a significant potential for aggressive behavior, and close follow-up of affected patients should be maintained for many years. Initial treatment should be aggressive in an attempt to prevent recurrence.  相似文献   
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BACKGROUND: The association of serum lipids with coronary heart disease has been studied extensively in middle-aged men and, to a lesser extent, in similar women. Less well defined are lipid variables predictive of CHD in individuals of age > or = 60 years. METHODS AND RESULTS: The Systolic Hypertension in the Elderly Program recruited 4736 persons (mean age, 72 years; 14% were black; and 43% were men). Mean systolic and diastolic blood pressures were 170 and 77 mm Hg, respectively. Baseline mean total cholesterol was 6.11 mmol/L (236 mg/dL); HDL cholesterol, 1.39 mmol/L (54 mg/dL); and non-HDL cholesterol, 4.72 mmol/L (182 mg/dL). Triglyceride levels were 1.62 mmol/L (144 mg/dL) for fasting participants and 1.78 mmol/L for the total group. LDL cholesterol, estimated in fasting samples with triglycerides of < 4.52 mmol/L, averaged 3.98 mmol/L (154 mg/dL). Mean follow-up was 4.5 years. In multivariate Cox regression analyses, baseline total, non-HDL, and LDL cholesterol levels and the ratios of total, non-HDL, and LDL to HDL cholesterol were significantly related to CHD incidence. HDL cholesterol and triglycerides were not significant in these analyses. In fasting participants with triglyceride levels of < 4.52 mmol/L, a 1.03 mmol/L (40 mg/dL) higher baseline total, non-HDL, or LDL cholesterol was associated with a 30% to 35% higher CHD event rate. CONCLUSIONS: The results of this study support the concept that serum lipids are CHD risk factors in older Americans.  相似文献   
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The interaction of cytotrophoblast with maternal endometrium, especially endometrial blood vessels, was examined in macaque gestational stages between 2 and 8 days after the onset of implantation. Serial sectioning of these early implantation sites allowed immunostaining of consecutive sections with a number of different antibodies, facilitating cell identification. In the earliest implantation site, immunostaining showed that antibody to cytokeratin stained cytotrophoblast, syncytial trophoblast, epithelial plaque and endometrial gland cells. However, only those cytotrophoblast cells near the maternal-fetal border and within vessels showed surface staining for neural cell adhesion molecules and only syncytial trophoblast showed SP1 reactivity. Even at this early stage cytotrophoblast filled the lumen of superficial arterioles, whereas dilated venules contained only a few cytotrophoblast cells. In later stages endovascular cytotrophoblast not only plugged many spiral arterioles but also migrated into the walls of these arterioles, and progressed into deeper coils. Displacement of endothelial cells and disruption of vessel walls were illustrated with antibody to factor VIII, TGF alpha, and desmin. Clusters of cytotrophoblast cells at the fetal-maternal interface tended to bypass clusters of epithelial plaque cells and larger clusters of maternal fibroblasts, but readily entered all vascular spaces. Consequently the vascular system constituted a major pathway of invasion, although the arterioles were the only component substantially invaded beyond the trophoblastic-shell/endometrial border.  相似文献   
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