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BACKGROUND AND METHOD: A randomised controlled trial in locally advanced non-small cell lung cancer (NSCLC), compared CHART which employs 36 fractions of 1.5 Gy 3 times per day to give 54 Gy in 12 consecutive days with conventional radiotherapy-30 fractions of 2 Gy to a total dose of 60 Gy in 6 weeks. A total of 563 patients were entered between April 1990 and April 1995. This report is based upon the data updated to 1 April 1998. RESULTS: The analysis of the mature data shows that the benefits previously reported have been maintained. Overall there was a 22% reduction in the relative risk of death, which is equivalent to an absolute improvement in 2 year survival of 9% from 20 to 29% (P = 0.008) and a 21% reduction in the relative risk of local progression (P = 0.033). In the large subgroup of patients with squamous cell cancer which accounted for 81% of the cases, there was a 30% reduction in the relative risk of death, which is equivalent to an absolute improvement in 2 year survival of 13% from 20 to 33% (P = 0.0007) and a 27% reduction in the relative risk of local progression (P = 0.012). Furthermore, in squamous carcinoma there was a 25% reduction in the relative risk of local and/or distant progression (P = 0.025) and 24% reduction in the relative risk of metastasis (P = 0.043). There was no evidence that CHART gave more or less benefit in any other subgroup. CONCLUSION: This analysis of mature data confirms that CHART is superior to conventional radiotherapy in achieving local tumour control and survival in locally advanced NSCLC. This demonstrates the importance of cellular repopulation as a cause of failure in the radiotherapy of NSCLC. The reduction in the risk of metastasis confirms that improved local tumour control, even in lung cancer, can reduce the incidence of metastasis. This trial shows that control of local tumour can lead to an improvement in long term survival.  相似文献   
997.
BACKGROUND: Patients on chronic hemodialysis or peritoneal dialysis often develop an inflammatory state that causes morbidity and mortality. Cross-sectional studies of dialysis patients have determined that C-reactive protein (CRP) is a predictor of morbidity. Little is known as to whether CRP, cytokines, such as IL-6 and IL-1beta that stimulate the synthesis of CRP, or matrix metalloproteinases (MMPs) are markers of inflammation in patients on dialysis. METHODS: We assayed by ELISA serum levels of MMP-2, MMP-3, IL-6 and CRP in healthy individuals and in patients with pre-end-stage renal disease (pESRD, n = 10), peritoneal dialysis (PD, n = 11), hemodialysis (HD, n = 17) and renal transplant (TX, n = 10). RESULTS: MMP-2 was significantly elevated before dialysis, perhaps indicative of progressive chronic renal sclerosis. MMP-3 was markedly elevated in hemodialysis patients but not in pESRD or PD patients, and may be related to the hemodialysis process and/or accelerated atherogenesis in these patients. IL-6 was significantly elevated in all patient groups, including pESRD patients. There were no statistically significant differences in CRP levels among the study groups. CRP correlated with IL-6, but not with MMP-2 or MMP-3. CONCLUSIONS: The data indicate that there are measurable differences in the expression of MMPs within the dialysis patient population. Because dialysis can be associated with local and systemic inflammation, increased levels of MMP-3 in the hemodialysis group may be a reflection of gene stimulation induced by inflammatory cytokines and should be considered as a marker of chronic, local inflammation.  相似文献   
998.

Background

Community-acquired pneumonia is the most common infectious cause of death in the US. Over the last 2 decades, patient characteristics and clinical care have changed. To understand the impact of these changes, we quantified incidence and mortality trends among elderly adults.

Methods

We used Medicare claims to identify episodes of pneumonia, based on a validated combination of diagnosis codes. Comorbidities were ascertained using the diagnosis codes located on a 1-year look back. Trends in patient characteristics and site of care were compared. The association between year of pneumonia episode and 30-day mortality was then evaluated by logistic regression, with adjustment for age, sex, and comorbidities.

Results

We identified 2,654,955 cases of pneumonia from 1987-2005. During this period, the proportion treated as inpatients decreased, the proportion aged ≥80 years increased, and the frequency of many comorbidities rose. Adjusted incidence increased to 3096 episodes per 100,000 population in 1999, with some decrease thereafter. Age/sex-adjusted mortality decreased from 13.5% to 9.7%, a relative reduction of 28.1%. Compared with 1987, the risk of mortality decreased through 2005 (adjusted odds ratio, 0.46; 95% confidence interval, 0.44-0.47). This result was robust to a restriction on comorbid diagnoses assessing for the results' sensitivity to increased coding.

Conclusions

These findings show a marked mortality reduction over time in community-acquired pneumonia patients. We hypothesize that increased pneumococcal and influenza vaccination rates as well as wider use of guideline-concordant antibiotics explain a large portion of this trend. © 2011 Elsevier Inc. All rights reserved.  相似文献   
999.
The aetiology of weight loss in patients with Parkinson''s disease is likely to be multifactorial. We studied 15 patients with Parkinson''s disease and 15 age- and sex-matched controls and looked for evidence of malabsorption due to small bowel bacterial overgrowth or alteration of intestinal permeability. There was a marked increase in orocaecal transit time in the patients with Parkinson''s disease, although lactulose hydrogen breath testing did not show evidence of small bowel bacterial contamination. Intestinal permeability measured by the differential sugar absorption test was also deranged. There was reduced absorption of mannitol in patients with Parkinson''s disease while lactulose absorption was similar in both groups, suggesting decreased non-mediated uptake across the enterocyte brush border membrane in patients with Parkinson''s disease.  相似文献   
1000.
The isolation from Cannabis sativa L. of an inhibitor of prostaglandin (PG) E2 production by cultured rheumatoid synovial cells is described. This agent, for which the name Cannflavin has been coined, is distinct from cannabinoids on the basis of isolation procedure, preliminary structural analysis and biological properties. The activity of Cannflavin has been compared with several established anti-inflammatory drugs and the major cannabinoids.  相似文献   
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