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PURPOSE: To study the effect of treatment time prolongation following initial dose acceleration on the response of subcutaneously growing R1H tumor. MATERIAL AND METHODS: Continuous standard fractionation (30 fractions/40 days) was compared to initially accelerated treatment (30 fractions/21 days) followed by five to two fractions per week yielding total treatment times from 40 to 72 days. Local tumor control was assessed as endpoint. RESULTS: Radiation dose to control 50% of the tumors (TCD50%) decreased statistically significant from 83.5 Gy (95% confidence interval [CI]: 78.6 .. 88.4) for standard fractionation to 74.1 Gy (95% CI: 72.7 .. 75.5) determined for all accelerated treatment arms (p = 0.003). Prolongation of treatment time after initial acceleration from 40 to 72 days led to a small but statistically not significant increase in TCD50% from 72.0 Gy (95% CI: 71.0 .. 72.9) to 76.2 Gy (95% CI: 69.9 .. 82.4) corresponding to a repopulated dose of 0.9 Gy per week. This time factor is considerably smaller than for conventional radiation treatment as determined in previous experiments. CONCLUSION: The results indicate that initially accelerated irradiation not only improves local tumor control but also minimizes the negative effect of treatment time prolongation. This might be due to changes in tumor cell repopulation kinetics.  相似文献   
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Gastric cancer still represents the second most common cause of gastrointestinal cancers in Germany. A disturbing issue is that at the time of diagnosis there are less than 15% of patients for whom a cure can be achieved. Nowadays, biological, histomorphological, molecular genetic and epidemiological data suggest that Helicobacter pylori eradication may lead to the prevention of gastric pre-neoplastic lesions and even gastric cancer. At present, eradication can be offered to selected patients and populations at increased risk, but more research is required before embarking on general and global H. pylori eradication for gastric cancer prevention. The main challenge is to determine how long mucosal abnormalities remain reversible and gastric cancer development can be halted.  相似文献   
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Background  

It is well known that physicians' night-call duty may cause impaired performance and adverse effects on subjective health, but there is limited knowledge about effects on sleep duration and recovery time. In recent years occupational stress and impaired well-being among anaesthesiologists have been frequently reported for in the scientific literature. Given their main focus on handling patients with life-threatening conditions, when on call, one might expect sleep and recovery to be negatively affected by work, especially in this specialist group. The aim of the present study was to examine whether a 16-hour night-call schedule allowed for sufficient recovery in anaesthesiologists compared with other physician specialists handling less life-threatening conditions, when on call.  相似文献   
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BACKGROUND: Necrotizing fasciitis (NF) is still a source of high morbidity and mortality. These difficult cases are increasingly referred to burn centers due to special wound and critical care issues. Here we examine our institution's recent experience with a large series of NF. METHOD: We performed a retrospective chart review of 32 consecutive patients over a 10-year period with NF who required radical surgical debridement and surface reconstruction. RESULTS: Overall survival was 85%, with average length of stay of 74.0+/-7.5 days for survivors (S) and 68.8+/-6.3 days for nonsurvivors (NS) (P>0.05). Time until first operation was 5.2 days in S and 3.4 days in NS (P<0.05). Patient age averaged 51.1+/-11.2 years for S and 57.0+/-12.0 years for NS (P<0.05). Survivors averaged 1.6 relevant comorbidities and NS averaged 3.6 (P<0.05). Affected total body surface (TBS) per patient averaged 6.8+/-3.3% for S and 10.2+/-5.1% for NS (P<0.05). All NS had affection of the trunk, and none of the patients with exclusive affection of extremities died. CONCLUSIONS: There were frequent delays in diagnosis and referrals to our institution, and progress can be made in educating the medical community to identify these patients. Not only the affected TBS and location but also comorbidities, age, and immediate surgical treatment are important prognostic factors. Referral to a specialized facility such as a burn center is urgently recommended for optimal surgical intervention, wound care, and critical care management.  相似文献   
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Background  Coccygodynia can cause severe pain and disability in patients. There are contradictions in the literature regarding the final results of coccygectomy for coccygodynia. We evaluated the long-term effects of coccygectomy on the intensity, characteristics, and manifestation of pain caused by coccygodynia to determine the adequacy of operation among treatment modalities. Materials and methods  Thirty-four patients with coccygodynia were treated by coccygectomy. In 22 cases, trauma, and in one case childbirth was the cause. 11 cases were regarded as idiopathic. The intensity, characteristics of pain, and the most painful activities were evaluated at an average of 7.6 (3–18) years of follow-up time. Results  Before the operation, all 34 patients had pain while sitting, moreover, 26 of them had pain during standing, walking, at night or a combination of these. 21 patients had intolerable or very intensive, mainly acute, sharp or burning pain. 11 patients had dyschesia, 2 had dysuria and 6 had dyspareunia. At follow-up, 7 patients were completely free of pain, 15 others had moderate, 11 medium, and only one patient had severe, but none had intolerable pain. Only seven patients had acute, sharp or burning pain postoperatively. The decrease of average pain score from 8.0 to 3.2 was significant (P < 10−12). The number of the patients with dyschesia and dyspareunia decreased from 11 to 7 and from 6 to 3, respectively. Two patients had dysuria, but their complaints did not change after the operation. One of the two patients who needed reoperation had an excellent final result, while the other remained unchanged. 12 and 16 patients (together 82%) regarded the final result of the operation excellent and good, respectively. The condition of five others did not change, while one became worse. The patients with younger age, smaller body mass index, and less co-morbidities had better final result. There were no serious complications. Conclusion  Coccygectomy for coccygodynia is a safe method to decrease the intensity of pain and other complaints of the patients. The operation can be the choice of treatment if conservative measures fail.  相似文献   
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