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71.
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
72.
N-Hydroxythalidomide (1d), a potential metabolite of thalidomide (1a), was synthesized from N-phthalyglutaminic acid anhydride (1b) and O-tetrahydropyraline hydroxylamine, followed by deprotection. The teratogenicity of 1d was studied using the Hen's-Egg-Test model which had been found applicable for 1a. 1d was more teratogenic to chicken embryos compared to 1a. The percentage of teratogenic malformations in the 1d groups was 28-46%, whereas the percentage in the 1a groups was 20-23%. The oxygen protected precursor N-hydroxythalidomide (1c) was less teratogenic (11-15%). 相似文献
73.
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
74.
M Herbst H Fritz H G Nüsslein B J Manger J R Kalden R Sauer 《Strahlentherapie und Onkologie》1986,162(1):25-30
Eleven patients with refractory rheumatoid arthritis were submitted to a total lymphoid irradiation up to a dose of 20 Gy. A constant improvement of clinical symptoms was observed in four out of the eleven patients already during the treatment and in the other patients not later than two months after. The frequency of attacks decreased and the number of joints involved in the attack was reduced. Morning rigidity and joint swellings decreased. One patient developed joint empyemas 4 and 26 months after the treatment. Four patients died in the meantime. In two patients the cause of death were renal insufficiency and a postoperative cardiogenic shock associated with generalized amyloidosis. The third patient died because of a toxically induced left cardiac decompensation with sepsis that could not be controlled by antibiotic drugs and multiple joint empyemas. The fourth patient developed an abscess after surgical treatment of a Kaposi syndrome. She died three months later from acute left cardiac decompensation. The therapy induced a lymphocytopenia with decrease of T helper lymphocytes and unchanged number of T suppressor lymphocytes. The constant therapy results of total lymphoid irradiation in primary chronic polyarthritis is probably due to this modification in the immune regulation. 相似文献
75.
Murat Hamit Aytar Fikret Doğulu Berker Cemil Ertan Ergün Gökhan Kurt Kemali Baykaner 《Child's nervous system》2007,23(6):719-721
Introduction Iniencephaly, a neural tube defect involving occiput and inion and combined with rachischisis of the cervical, thoracic spine,
and retroflexion position of the head is a very rare congenital abnormality of the fetus–newborn with a 0.1–10 of 10,000 prevalence.
This abnormality’s prognosis is thought to be dismal. This abnormality can be associated with other abnormalities such as
anencephaly, encephalocele, hydrocephalus, cyclopia, absence of the mandible, cleft lip and palate, cardiovascular disorders,
diaphragmatic hernia, renal abnormalities, overgrowth of the arms compared to the legs, and club food and gastrointestinal
atresia.
Discussion Most of the patients are dead born, and the others die in a few hours. There are only six previously documented long-term
survivors. In our case, our patient with iniencephalic signs and findings is still living. She is 2 years old now. We think
that this patient presents a mild form of iniencephaly. 相似文献
76.
Max Heiland Philipp Pohlenz Marco Blessmann Christian R Habermann Lars Oesterhelweg Philipp C Begemann Christian Schmidgunst Felix A S Blake Klaus Püschel Rainer Schmelzle Dirk Schulze 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):814-820
OBJECTIVE: The aim of this study was to evaluate soft tissue image quality of a mobile cone-beam computed tomography (CBCT) scanner with an integrated flat-panel detector. STUDY DESIGN: Eight fresh human cadavers were used in this study. For evaluation of soft tissue visualization, CBCT data sets and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) data sets were acquired. Evaluation was performed with the help of 10 defined cervical anatomical structures. RESULTS: The statistical analysis of the scoring results of 3 examiners revealed the CBCT images to be of inferior quality regarding the visualization of most of the predefined structures. Visualization without a significant difference was found regarding the demarcation of the vertebral bodies and the pyramidal cartilages, the arteriosclerosis of the carotids (compared with CT), and the laryngeal skeleton (compared with MRI). Regarding arteriosclerosis of the carotids compared with MRI, CBCT proved to be superior. CONCLUSIONS: The integration of a flat-panel detector improves soft tissue visualization using a mobile CBCT scanner. 相似文献
77.
Zusammenfassung Kniegelenkluxationen sind seltene, aber schwer wiegende Verletzungen mit z. T. erheblichen Folgen. Begleitende Nerven- und Gefäßverletzungen sind nicht selten. Bei spontaner Reposition kann das Verletzungsausmaß initial unterschätzt werden. Die primäre Diagnostik muss die neurologische Untersuchung sowie die sichere Beurteilung des Gefäßstatus einschließen. Die Sicherung der Durchblutung des betroffenen Beins steht in der Akutphase im Vordergrund, Läsionen müssen notfallmäßig operativ versorgt werden. Bei drohendem Kompartment ist eine Faszienlogenspaltung erforderlich, die Instabilität wird temporär mittels Fixateur externe transfixiert. Bei Hochrasanztraumen sind Begleitverletzungen auszuschließen, bei sedierten und beatmeten Patienten z. B. mit Spiral-CT. Sind nur die Kreuzbänder betroffen, kann ein arthroskopisch gestützter Ersatz vorgenommen werden, Transplantate werden bevorzugt von der Gegenseite entnommen. Die im angloamerikanischen Sprachraum verwendeten Allografts haben sich in unserer Region noch nicht durchgesetzt. Bei ausgedehnten Kapselläsionen und Beteiligung der Kollateralbänder sind arthroskopische Techniken nicht indiziert, es sollte offen rekonstruiert und ggf. augmentiert werden; sekundär verbliebene Instabilitäten können gezielt dem Bandersatz zugeführt werden. 相似文献
78.
Stereological evaluation of liver volume in living donor liver transplantation using MDCT via the Cavalieri method. 总被引:4,自引:0,他引:4
Cihan Duran Bulent Aydinli Yaman Tokat Yildiray Yuzer Mecit Kantarci Metin Akgun Kamil Yalcin Polat Bünyami Unal Refik Killi S Selcuk Atamanalp 《Liver transplantation》2007,13(5):693-698
In living donor liver transplantation (LDLT), obtaining the precise volume of the graft is very important to decrease volume-related postoperative complications, especially in cases with suspected small-for size grafts. We used stereology based on the Cavalieri method (CM), a new method to measure liver graft volume, and compared the results with those obtained through intraoperative measurement (IOM) and through multidetector computed tomography (MDCT) measurement. Liver volumes estimated using the 3 methods were well-correlated with each other (r(2) = 0.94 and P < 0.001 for IOM and CM; r(2) = 0.91 and P < 0.001 for IOM and MDCT, and r(2) = 0.95 and P < 0.001 for CM and MDCT); however, they were different from each other (in descending order, 908 +/- 124 cm(2), 861 +/- 121 cm(2), and 777 +/- 168 cm(2) for MDCT, CM, and IOM, respectively). Although MDCT and CM overestimated the volumes, the results of CM were almost similar to those obtained via IOM. In conclusion, our results suggest that CM measured the liver graft volume more reliably. Thus, its use, particularly in cases with suspected small-for-size graft, may prove useful. 相似文献
79.
Dr. med. H. Kuhn Dr. med. R. Gerdes-Kuhn Prof. Dr. med. H.-H. Küster 《Fu? & Sprunggelenk》2007,5(1):26-31
The Cinderella shoe syndrome specifies a commonly observed, not yet labeled disproportion of footwear and the morphologic conditions of the wearer. Disproportioned shoes and socks are worn–frequently unconsciously–due to personal reasons, fashion trends, misinformation and wrong advice; they can induce severe foot disorders. The Cinderella shoe syndrome has an important significance within the development, the treatment and the recurrence-prophylaxis of foot disorders, as well as in the assessment of possible reasons for recurrence after foot surgery. To recognize it, to treat individual psychologic reasons, to give support in the choice of footwear, to inform about and to change social reasons are all challenges of the foot surgeon. 相似文献
80.
Esra Baltacio?lu Ferda Alev Akalin Eda Topalo?lu Erkan Süküro?lu Umit Cobano?lu 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):803-808
Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease. 相似文献