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One hundred eighty-four patients with advanced measurable colorectal cancer not previously treated with chemotherapy were entered into a prospective randomized clinical trial by the Mid-Atlantic Oncology Program (MAOP) to assess the value of weekly cisplatin (20 mg/m2) when added to a protracted schedule of 5-fluorouracil (5-FU) infusion (PIF) at 300 mg/m2/d for 10 weeks of every 12 weeks. The liver was the primary indicator lesion in approximately 75% of the study group. All tumor measurements required radiographic confirmation. The response rate in the PIF alone arm was 35% (29 of 83; 95% confidence interval [CI], 25% to 46%) compared with 33% (28 of 85; 95% CI, 23% to 44%) for the arm in which weekly cisplatin was added to PIF. The median survival times were 11.8 and 11.2 months in the two groups. Weekly cisplatin does not appear to add to the effectiveness of PIF in colorectal carcinoma.  相似文献   
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Cornish GH  Sinclair LV  Cantrell DA 《Blood》2006,108(2):600-608
Although interleukin 2 (IL-2) and IL-15 signal through the common gamma chain (gammac) and through IL-2 receptor beta-chain (CD122) subunits, they direct distinct physiologic and immunotherapeutic responses in T cells. The present study provides some insight into why IL-2 and IL-15 differentially regulate T-cell function by revealing that these cytokines are strikingly distinct in their ability to control protein synthesis and T-cell mass. IL-2 and IL-15 are shown to be equivalent mitogens for antigen-stimulated CD8(+) T cells but not for equivalent growth factors. Antigen-primed T cells cannot autonomously maintain amino acid incorporation or de novo protein synthesis without exogenous cytokine stimulation. Both IL-2 and IL-15 induce amino acid uptake and protein synthesis in antigen-activated T cells; however, the IL-2 response is strikingly more potent than the IL-15 response. The differential action of IL-2 and IL-15 on amino acid uptake and protein synthesis is explained by temporal differences in signaling induced by these 2 cytokines. Hence, the present results show that cytokines that are equivalent mitogens can have different potency in terms of regulating protein synthesis and cell growth.  相似文献   
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This is a retrospective analysis of the management of the neck in 84 patients with squamous cell carcinoma of the oral tongue treated with curative intent between 1968 and 1985. Patients with a clinically negative neck were treated to the neck only if the patient was thought to have a reasonable probability of occult neck metastases. This policy resulted in a 3-year adjusted neck control rate for N0 patients treated with limited (no, bilateral-partial, or ipsilateral) neck therapy of 38% compared with 95% for patients treated with bilateral, whole neck irradiation (p less than .001). None of the relapses in the patients with limited irradiation were in the treatment portal. Attempted salvage with a neck dissection resulted in cure in only 30%. The 3-year adjusted neck control rate for the N1 and N2 patients treated with total neck irradiation and surgery was 75% and 63%, respectively. The location of recurrence in these patients was in the field of irradiation, but contralateral to the side of the neck dissection.  相似文献   
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BACKGROUND: The aetiology of pityriasis alba (PA), a common dermatosis in childhood, is still controversial. The objective of this study was to assess the possible aetiopathogenic factors of this disease in infants. METHODS: Forty-four patients with PA and 31 healthy children were examined and compared. Personal hygiene habits, sun exposure, presence of Staphylococcus aureus in nasal fossae and presence of major or minor signs of atopy were assessed during anamnesis and physical examination. Susceptibility to ultraviolet (UV) B radiation was measured by the onset of a contact hypersensitivity reaction to diphenylcyclopropenone in individuals sensitized in previously irradiated areas. RESULTS: The prevalence of PA was higher in individuals with darker skin, in high phototype categories, as well as in males. The number of daily baths and sun exposure between 10.00 h and 15.00 h were significantly higher in the PA group when compared with controls (P = 0.03 and P = 0.0015, respectively). The presence of atopy signs was more common in pityriasis patients (P = 0.002). Susceptibility to UVB radiation was 29.6% in the PA group vs. 29.0% in the control group; nevertheless, important differences were found after stratification in order to control possible confounding factors. The presence of S. aureus in the nostrils was equal in both groups. CONCLUSIONS: Our results confirm that PA, in our population, is more prevalent in males and in individuals in higher phototype categories. In those with inadequate personal hygiene and sun exposure habits the disease is more accentuated, demonstrating that the xerosis presenting in individuals with atopic diathesis is an important element in the development of the disease. S. aureus is not an important aetiopathogenic factor in PA. Susceptibility to UVB becomes important when related to the patient's phototype.  相似文献   
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To evaluate the clinical value of two serologic tumor markers, squamous cell carcinoma-associated antigen and plasma lipid-bound sialic acid, for identifying cancers of the head and neck, plasma specimens were obtained from patients receiving care for untreated newly diagnosed cancers of the head and neck, routine surveillance for recurrence, or treatment for chronic nonmalignant otolaryngologic conditions. Using identical methods at two institutions, levels of both markers were determined blind to diagnoses for patients with biopsy-proven cancers of the head and neck (n = 134) and for those defined as cancer free based on clinical evaluation for 6 months (n = 140). Disease status was determined blind to tumor marker level results. Cancer prevalence was 48.9%. Applying standard normal limits used alone, plasma lipid-bound sialic acid test sensitivity was 63.4% and specificity was 77.9%. For squamous cell carcinoma-associated antigen alone, test sensitivity was 27.6% and specificity was 85.0%. Neither test alone appears sensitive enough to effectively detect early cancers of the head and neck. When the results of both tests in series combination were positive, sensitivity was 18.7% and specificity was 95.0%. If either was positive in parallel combination, sensitivity was 72.4% and specificity was 68.0%. Further evaluation is required that applies different definitions of normal and determines longitudinal changes with disease status.  相似文献   
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