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BACKGROUND AND PURPOSE: There is concern about the increase of radiation-induced malignancies with the application of modern radiation treatment techniques such as intensity-modulated radiotherapy (IMRT) and proton radiotherapy. Therefore, X-ray scatter and neutron radiation as well as the impact of the primary dose distribution on secondary cancer incidence are analyzed. MATERIAL AND METHODS: The organ equivalent dose (OED) concept with a linear-exponential and a plateau dose-response curve was applied to dose distributions of 30 patients who received radiation therapy of prostate cancer. Three-dimensional conformal radiotherapy was used in eleven patients, another eleven patients received IMRT with 6-MV photons, and eight patients were treated with spot-scanned protons. The treatment plans were recalculated with 15-MV and 18-MV photons. Secondary cancer risk was estimated based on the OED for the different treatment techniques. RESULTS: A modest increase of 15% radiation-induced cancer results from IMRT using low energies (6 MV), compared to conventional four-field planning with 15-MV photons (plateau dose-response: 1%). The probability to develop a secondary cancer increases with IMRT of higher energies by 20% and 60% for 15 MV and 18 MV, respectively (plateau dose-response: 2% and 30%). The use of spot-scanned protons can reduce secondary cancer incidence as much as 50% (independent of dose-response). CONCLUSION: By including the primary dose distribution into the analysis of radiation-induced cancer incidence, the resulting increase in risk for secondary cancer using modern treatment techniques such as IMRT is not as dramatic as expected from earlier studies. By using 6-MV photons, only a moderate risk increase is expected. Spot-scanned protons are the treatment of choice in regard to secondary cancer incidence.  相似文献   
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Abstract Background: Does there exist a difference in the outcome of severely injured children and severely injured healthy adults? Methods: The data of 1,566 severely injured patients, treated between May 1998 and December 2002 in our emergency department of the University Essen/Germany, were analyzed. Patients with an injury severity score (ISS) > 24 were included in the present study. Patients younger as 18 (17) years were located to the children group c. Patients aged 18 and up to the age of 54 were included in the adult group a. Results: Fifty-four children and 252 adults met the selection criteria. ISS and the Glasgow coma scale (GCS) before intubation were not statistically different in both groups. Seriously injured children stayed significantly shorter on the intensive care unit, required significantly less ventilator days. Furthermore, the incidence of single organ failure (SOF) and multiple organ failure (MOF) was significantly lower in the children group. Mortality in the children group (29.6%) was lower than that in the adult group (33.7%). There was no death due to MOF in the children group as compared to 2.4% (n = 6) in the adults. Conclusion: The incidence of SOF and MOF was significantly lower in the children group although there was no difference in ISS, GCS and injury patterns. The prognosis of severely injured children was found to be better than those of adults. Moreover, there was no death due to MOF in the children group.  相似文献   
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Abstract Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation to detect pelvic ring fractures and to identify those with severe bleeding. Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the iliac wings. Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity 97.0%, positive predictive value 38.1%, negative predictive value 99.9%). Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture as being the source of bleeding quite unlikely.  相似文献   
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In an in vitro study, 10 gallbladders of adult pigs and 6 gallbladders of lambs, all removed immediately after slaughtering, were stimulated in a water bath by electric means to induce active contraction. Gallbladder emptying was followed by ultrasonography employing five measurement procedures: (1) gallbladder width, (2) longitudinal planimetry, (3) transverse planimetry, (4) ellipsoid method, and (5) sum of cylinders method. In an in vivo investigation, gallbladder emptying of 30 volunteers (12 healthy subjects, 18 diabetics) was evaluated in the same way after ingestion of a fatty meal. Gallbladder width was found to be unsuitable to estimate the decrease in gallbladder volume due to a nonlinear relation of the parameters. Longitudinal planimetry tended to be less valid than transverse planimetry in assessing gallbladder volume reduction. The most valid estimation of gallbladder volume decreases was obtained by the two three-dimensional procedures. However, in neither in vitro nor in vivo could a significant difference between the sum of cylinders method and the ellipsoid method in determining relative volume reduction be established. We conclude that a three-dimensional measurement procedure should be used for valid assessments of gallbladder motility. However, according to our data there is no advantage in using the time-consuming sum of cylinders method compared to the simple ellipsoid method.  相似文献   
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The problem of poverty leads to increased use of both legal and illegal drugs. Tobacco and alcohol are legal drugs that cause particular concern. Both drugs are widely abused in Germany by people attempting to escape their everyday problems. For decades it has been known that tobacco and alcohol use are more prevalent in lower socio-economic groups of society (those with low educational achievement, compared with people with further or higher education qualifications). Tobacco and alcohol use is particularly high among the unemployed, either temporarily or long-term, as well as people living alone. Children and women are more concerned about smoking than men. Female loneliness, often accompanied by the appearance of depressive reactions or of depression, increases the likelihood of cigarette smoking. Poor people spend up to 20% of their income on tobacco. In many industrialized countries, the age of onset of smoking is becoming younger and younger, increasing the risk of development of avoidable tobacco-related illnesses at an earlier age. This means that young smokers who develop chronic tobacco-related illnesses will require medical care over many years, increasing the cost of treating tobacco-related disease. Within the next few years, effective prevention programs against smoking must be developed, particularly for the lower socio-economic populations, in order to stop the cost of healthcare systems spiraling over the coming decades.  相似文献   
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Background To our best knowledge, Panton–Valentine leucocidin (PVL)-positive methicillin-sensitive Staphylococcus aureus (MSSA) has not been described yet as cause for severe pyomyositis. Case report We present a 23-year-old apparently healthy male patient without any typical predisposing findings who developed severe pyomyositis secondary to an operated pilonidal cyst. In the follow-up, the patient showed signs of immunocompromisation. The causative agent for purulent infection of multiple muscles was a MSSA strain harbouring PVL toxin. Results In the reported case, aggressive antibiotic and surgical treatment with additional application of immunoglobulins has lead to recovery from the disease without relapse. Conclusions PVL-positive S. aureus are associated with skin diseases, multiple abscesses and often complicated by severe sepsis and necrotising pneumonia. Under such circumstances, the mortality rate can reach up to 75%. In addition, the PVL toxin can cause immunocompromisation and might be therefore involved in the aetiology of pyomyositis. Aggressive antibiotic and surgical treatment with additional application of immunoglobulins is recommended for treatment.  相似文献   
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Authors' reply     
Carlo  Pancaro  Dieter  Renz 《Paediatric anaesthesia》2005,15(11):1024-1024
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