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971.
Alpha-interferon does not increase the efficacy of 5-fluorouracil in advanced colorectal cancer 总被引:3,自引:0,他引:3
Thirion P Piedbois P Buyse M O'Dwyer PJ Cunningham D Man A Greco FA Colucci G Köhne CH Di Constanzo F Piga A Palmeri S Dufour P Cassano A Pajkos G Pensel RA Aykan NF Marsh J Seymour MT;Meta-Analysis Group in Cancer 《British journal of cancer》2001,84(5):611-620
Two meta-analyses were conducted to quantify the benefit of combining alpha-IFN to 5FU in advanced colorectal cancer in terms of tumour response and survival. Analyses were based on a total of 3254 individual patient data provided by principal investigators of each trial. The meta-analysis of 5FU +/- LV vs. 5FU +/- LV + alpha-IFN combined 12 trials and 1766 patients. The meta-analysis failed to show any statistically significant difference between the two treatment groups in terms of tumour response or survival. Overall tumour response rates were 25% for patients receiving no alpha-IFN vs. 24% for patients receiving alpha-IFN (relative risk, RR = 1.02), and median survivals were 11.4 months for patients receiving no alpha-IFN vs. 11.5 months for patients receiving alpha-IFN (hazard ratio, HR = 0.95). The meta-analysis of 5FU + LV vs. 5FU + alpha-IFN combined 7 trials, and 1488 patients. This meta-analysis showed an advantage for 5FU + LV over 5FU + alpha-IFN which was statistically significant in terms of tumour response (23% vs. 18%; RR = 1.26;P = 0.042), and of a borderline significance for overall survival (HR = 1.11;P = 0.066). Metastases confined to the liver and primary rectal tumours were independent favourable prognostic factors for tumour response, whereas good performance status, metastases confined to the liver or confined to the lung, and primary tumour in the rectum were independent favourable prognostic factors for survival. We conclude that alpha-IFN does not increase the efficacy of 5FU or of 5FU + LV, and that 5FU + alpha-IFN is significantly inferior to 5FU + LV, for patients with advanced colorectal cancer. 相似文献
972.
Sasson AR Fowble B Hanlon AL Torosian MH Freedman G Boraas M Sigurdson ER Hoffman JP Eisenberg BL Patchefsky A 《Cancer》2001,91(10):1862-1869
BACKGROUND: Lobular carcinoma in situ (LCIS) is a known risk factor for the development of invasive breast carcinoma. However, little is known regarding the impact of LCIS in association with an invasive carcinoma on the risk of an ipsilateral breast tumor recurrence (IBTR) in patients who are treated with conservative surgery (CS) and radiation therapy (RT). The purpose of this study was to examine the influence of LCIS on the local recurrence rate in patients with early stage breast carcinoma after breast-conserving therapy. METHODS: Between 1979 and 1995, 1274 patients with Stage I or Stage II invasive breast carcinoma were treated with CS and RT. The median follow-up time was 6.3 years. RESULTS: LCIS was present in 65 of 1274 patients (5%) in the study population. LCIS was more likely to be associated with an invasive lobular carcinoma (30 of 59 patients; 51%) than with invasive ductal carcinoma (26 of 1125 patients; 2%). Ipsilateral breast tumor recurrence (IBTR) occurred in 57 of 1209 patients (5%) without LCIS compared with 10 of 65 patients (15%) with LCIS (P = 0.001). The 10-year cumulative incidence rate of IBTR was 6% in women without LCIS compared with 29% in women with LCIS (P = 0.0003). In both groups, the majority of recurrences were invasive. The 10-year cumulative incidence rate of IBTR in patients who received tamoxifen was 8% when LCIS was present compared with 6% when LCIS was absent (P = 0.46). Subsets of patients in which the presence of LCIS was associated with an increased risk of breast recurrence included tumor size < 2 cm (T1), age < 50 years, invasive ductal carcinoma, negative lymph node status, and the absence of any adjuvant systemic treatment (chemotherapy or hormonal therapy) (P < 0.001). LCIS margin status, invasive lobular carcinoma histology, T2 tumor size, and positive axillary lymph nodes were not associated with an increased risk of breast recurrence in these women. CONCLUSIONS: The authors conclude that the presence of LCIS significantly increases the risk of an ipsilateral breast tumor recurrence in certain subsets of patients who are treated with breast-conserving therapy. The risk of local recurrence appears to be modified by the use of tamoxifen. Further studies are needed to address this issue. 相似文献
973.
974.
The present study concerns methodological issues of electrochemical recordings using Nafion-coated 30 microm diameter single carbon fiber microelectrodes for high-speed chronoamperometric measurements of biogenic amines. First, the single carbon fiber microelectrodes were coated with Nafion and dried at 85 vs. 200 degrees C and their recording properties were determined. Second, the effects of shifts in solution pH, ionic strength, changes in recording solution levels of Ca(2+) or Mg(2+) and temperature on the recording characteristics and sensitivity of Nafion-coated high temperature dried (200 degrees C) single carbon fiber microelectrodes for measures of dopamine were studied. These studies showed that the high temperature drying of the Nafion produced a microelectrode with better recording properties: higher selectivity for cations versus anions, increased differences between the reduction and oxidation current ratios for the identification of dopamine versus serotonin, and more rapid response times. In addition, these studies demonstrated that the chronoamperometric recordings were insensitive to small changes in pH and divalent cations such as Ca(2+) or Mg(2+). However, increases in ionic strength decreased the sensitivity of the microelectrodes, while increases in temperature produced increases in the sensitivity of the microelectrodes for biogenic amines. These data support that Nafion-coated high temperature (200 degrees C) dried microelectrodes have enhanced recording properties as compared to microelectrodes, which are coated with Nafion and dried at 85 degrees C. In addition, high-speed chronoamperometric recordings of biogenic amines are not affected by solution changes in divalent cations (Ca(2+) or Mg(2+)). 相似文献
975.
BACKGROUND: Hearing loss after intracranial and spinal procedures involving cerebrospinal fluid loss is rarely reported in the literature. We report a patient who suffered from delayed hearing loss after cerebrospinal fluid shunting that improved after revising the shunt to a higher-pressure valve. CASE DESCRIPTION: A 32-year-old woman presented with bilateral hearing loss 4 years after ventriculoperitoneal shunting for communicating hydrocephalus. Her otologic work-up revealed sensorineural hearing loss. In an attempt to improve her hearing, 6 years after the hearing loss began (10 years after the shunt was placed), she underwent a shunt revision in which her valve was changed to a higher-pressure device. After the procedure, she had a significant improvement in her speech discrimination and a mild improvement in her pure tone recognition. These changes were documented with serial audiograms. CONCLUSION: Hearing loss after cerebrospinal shunting procedures is not always limited to the immediate postoperative period. It may be a late complication of cerebrospinal fluid diversion. Chronic hearing loss after ventriculoperitoneal shunting may be treatable by changing the valve to a higher-pressure device. The etiology of hearing loss from intracranial hypotension is briefly discussed. 相似文献
976.
Association Between COLIA1 Sp1 Alleles and Femoral Neck Geometry 总被引:4,自引:0,他引:4
A.M. Qureshi F.E.A. McGuigan D.G. Seymour J.D. Hutchison D.M. Reid S.H. Ralston 《Calcified tissue international》2001,69(2):67-72
Genetic factors play an important role in the pathogenesis of osteoporosis by affecting bone mineral density and other predictors of osteoporotic fracture risk such as ultrasound properties of bone and skeletal geometry. We previously identified a polymorphism of a Sp1 binding site in the Collagen Type 1 Alpha 1 gene (COLIA1) that has been associated with reduced BMD and an increased risk of osteoporotic fractures in several populations. Here we looked for evidence of an association between COLIA1 Sp1 alleles and femoral neck geometry. The study group comprised 153 patients with hip fracture, and 183 normal subjects drawn at random from the local population. Femoral neck geometry was assessed by analysis of pelvic radiographs in the fracture patients and DXA scan printouts in the population-based subjects. The COLIA1 genotypes were detected by polymerase chain reaction and were in Hardy Weinberg equilibrium: "SS" = 222 (66%); "Ss" = 105 (31.3%); and "ss" = 9 (2.7%). There was no significant difference in hip axis length or femoral neck width between the genotype groups, but femoral neck-shaft angle was increased by about 2 degrees in the Ss/ss genotype groups (n = 114) when compared with SS homozygotes (n = 222) (P = 0.001). Previous studies have suggested that an increased femoral neck-shaft angle may increase the risk of hip fracture in the event of a sideways fall by influencing the forces that act on the femoral neck. The association COLIAI genotype and increased femoral neck angle noted here may therefore contribute to the BMD-independent increase in hip fracture risk noted in previous studies of individuals who carry the 's' allele. 相似文献
977.
978.
Rom WN Hammar SP Rusch V Dodson R Hoffman S 《American journal of industrial medicine》2001,40(2):211-214
BACKGROUND: Anthophyllite asbestos has been reported to cause asbestosis, lung cancer, mesothelioma, and pleural plaques in occupationally exposed workers. Anthophyllite has also been associated with pleural plaques in Finland and Japan among those who live near mines and mills and have neighborhood or environmental exposure. METHODS: We evaluated a 38-year-old patient with pleural mesothelioma who lived, attended school, and delivered newspapers near a manufacturing facility that used exclusively anthophyllite asbestos fiber from ages 8-17 years. He had no work exposure to asbestos. RESULTS: The pleural mesothelioma was an epithelial type with tubulopapillary structures and was treated with an extrapleural pneumonectomy followed by radiation therapy. The malignant cells were positive by immunohistochemistry for cytokeratin but negative for carcinoembryonic antigen, S100, B72.3, and leu M1 antigen. Anthophyllite fibers were > 5 microm in length in lung tissue compared to 3 microm from a general population study. CONCLUSIONS: Anthophyllite asbestos has been associated with neighborhood environmental exposure and pleural plaques; we now report a neighborhood exposure and pleural mesothelioma. 相似文献
979.
Activated peripheral T-lymphocytes are increased in both pre-insulin-dependent diabetes mellitus (IDDM) patients and in recently diagnosed IDDM patients, as well as in various forms of acute stress. We studied the in vivo T-lymphocyte activation in six patients in severe diabetic ketoacidosis (DKA) prior to treatment, after 24 h of treatment and > or =5 days after admission. Five of the six patients showed an increased percentage of activated T-lymphocytes based on the expression of HLA-DR at 24 h of treatment when compared to the admission percentage of activation (P<.05). There was no correlation to the admission serum glucose, osmolality, or electrolytes. Serum pH showed a trend toward an inverse correlation, but was not statistically significant. We speculate that T-lymphocyte activation plays a role in the progression of the acute complications of subclinical brain edema and interstitial pulmonary edema of DKA. This process could also be another factor in the progression of the chronic complications of IDDM in addition to the well-established effects of hyperglycemia and hypertension. 相似文献
980.