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91.
92.
Prof. Dr. Wolfgang Dörr Sabine Köst Klaus Keinert Felix-Herbert Glaser Gerd Endert Thomas Herrmann 《Strahlentherapie und Onkologie》2006,182(1):1-8
PURPOSE: To compare tests for intestinal function with clinical scores after abdominal irradiation. PATIENTS AND METHODS: At the Department of Radiotherapy, Erfurt, Germany, intestinal changes were studied in 91 patients receiving abdominal radiotherapy between 1992 and 1996. Conventional fractionation (1.8-2 Gy per fraction, total doses 30.6-62.5 Gy) was applied. Before and at weekly intervals during radiotherapy, the clinical response was scored according to RTOG/EORTC for the upper and lower gastrointestinal (GI) tract. Resorption tests for vitamin B(12) and D-xylose were performed before the onset and immediately after treatment. RESULTS: The clinical response displayed a well-defined dose-effect relationship with grade 1 effects in 5% and 50% of the patients at about 10 Gy and 50 Gy, respectively. For grade 2 reactions, 5%- and 50%-effective doses were 20-30 Gy and 60-80 Gy. Effects in the upper and lower GI tract were highly correlated. Changes in body weight did not show a correlation with other clinical symptoms. Changes in resorption also displayed a significant dose effect. However, no correlation was found with the clinical symptoms in the individual patient. CONCLUSION: In the present study, the clinical manifestation of intestinal side effects according to RTOG/EORTC criteria was reflected by neither the vitamin B(12) nor by the D-xylose resorption test. Hence, these tests cannot be regarded as useful for objective quantitation of intestinal radiation injury. 相似文献
93.
Maximum anchorage often presents a problem that is difficult to solve during orthodontic tooth movement. Stationary, skeletal anchorage can be achieved in a simple, minimally-invasive manner, and unwanted tooth movements in opposite directions can be prevented by using transmucosally-inserted bone screws.Our initial experience using the FAMI screw as an orthodontic micro-implant proved to be clinically and histologically successful. 相似文献
94.
M. Knappik U. Börner T. Jelinek 《European journal of clinical microbiology & infectious diseases》2005,24(10):701-703
The study presented here was conducted to evaluate the performance of the newly available RIDASCREEN Set (R-Biopharm AG, Darmstadt,
Germany) for the detection of immunoglobulin G antibodies against Entamoeba histolytica. The sensitivity and specificity of this new enzyme-linked immunosorbent assay were evaluated using a panel of sera from
239 individuals. The assay was positive for 43 of 44 patients with invasive amebiasis, including all 18 patients with amebic
liver abscess, while it was negative for 190 of 195 adult controls who were either healthy individuals or patients with other
parasitic diseases. The kit was found to be highly specific (97.4%) and sensitive (97.7%) for detecting antibodies against
E. histolytica in humans. Although antibody titers in patients with amebic liver abscess tend to be higher on average than in patients with
invasive amebiasis, it is not possible to distinguish the two forms solely based on the results of this commercial test. 相似文献
95.
Priv.-Doz. Dr. Rüdiger Dissmann Joachim Schröder MD PhD Prof. Dr. med. Heinz Völler Prof. Dr. med. Steffen Behrens 《Clinical research in cardiology》2006,95(4):241-243
Summary During pacemaker implantation in a patient with permanent atrial fibrillation, it remained impossible to advance a passive
fixation lead with fins through the right atrium. However, a lead with a retractable screw easily passed the right atrium
and was positioned in the right ventricle. Transesophageal echocardiography revealed an extensive net–like perforated Eustachian
valve within the right atrium that had caused entrapment of the anchor fins during lead implantation. Remnants of embryonal
structures within the right atrium should be considered a rare possible barrier during pacemaker implantation. 相似文献
96.
Dietmar Georg PhD Bernhard Kroupa Petra Georg Peter Winkler Joachim Bogner Karin Dieckmann Richard Pötter 《Strahlentherapie und Onkologie》2006,182(8):473-480
PURPOSE: To compare commercial treatment-planning systems (TPS) for inverse planning (IP) and to assess constraint variations for specific IMRT indications. MATERIAL AND METHODS: For IP, OTP, XiO and BrainSCAN were used and step-and-shoot intensity-modulated radiotherapy (IMRT) delivery was assumed. Based on identical constraints, IP was performed for a prostate, head and neck, brain, and gynecologic case. IMRT plans were compared in terms of conformity/homogeneity, dose-volume histograms (DVHs), and delivery efficiency. For ten patients each of a class of indications, constraint variations were evaluated. RESULTS: IMRT plans were comparable concerning minimum target dose, homogeneity, conformity, and maximum doses to organs at risk. Larger differences were seen in dose gradients outside the target, monitor units, and segment number. Using help structures proved efficient to shape isodoses and to reduce segmentation workload. For IMRT class solutions, IP constraint variations depended on anatomic site. CONCLUSION: IP systems requiring doses as input and having objective functions based on physical parameters had a very similar performance. Constraint templates can be established for a class of IMRT indications. 相似文献
97.
98.
99.
Dr. Annette Raabe Cordula Petersen Andreas Krüll 《Strahlentherapie und Onkologie》2007,183(7):360-365
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
100.
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