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Precise knowledge of the biomechanic of the hip of man and of animal is necessary to evaluate the procedures of adaption of the femur after endoprosthesis with animal experiment and the transfer into the endoprosthesis of the human medicine. After functional-morphological and biomechanical researches (Pauwels), the upper femoral end of the man is highly stressed by bending at direct level while lowly stressed at sagittal level. The present own biomechanical analysis of the hip of the dog reveal - under consideration of the gaits "pace", "trot" and "gallop" - that the coxal end of the femur of the four-leg compared with that of man is highly stressed by bending at sagittal level as well as at direct level. The observations are herewith clearly explained that intense reconstructions of the bone at artificial human thighs are found mainly at lateral and medial circumference of the bed of the prosthesis, at animal experiment however at dorsal, ventral as well as medial circumference.  相似文献   
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Zusammenfassung Um die zusätzliche Verwendung von Kunstharzen zur Verankerung der Totalprothese der Hüfte zu umgehen, hat Mittelmeier eine selbsthaftende Tragrippenprothese mit besonders gestalteter Oberfläche des Prothesenstieles angegeben. Nach einjähriger Implantationsdauer im Tierexperiment (Hund) wird der endoprothetisch versorgte und der kontralaterale normale Femur des Hundes funktionell und morphologisch untersucht. Unter statischer Belastung werden mit Dehnungsmeßstreifen die Beanspruchung und in photographischen und Röntgenaufnahmen der Umbau des Knochens nach Prothetik untersucht. Im Bereich des Prothesenstieles ergeben sich Umbauvorgänge, welche mit den geänderten Beanspruchungen übereinstimmen. Der Knochen gleicht sich an eine in Richtung und Höhe gänzlich geänderte Beanspruchung durch eine Spongiosierung des oberen Teils der Femurdiaphyse zweckmäßig an. Dieser Vorgang wird als kompensatorische Metaphysierung des Schaftes bezeichnet (Diehl).
Stresses and functional adaptation of alloarthroplasty of the proximal femur in dogs using a selfcuring rippled prosthesisA comparative biomechanical and morphological study
Summary A self-adhesive prosthesis for youth patients is developed by Mittelmeier that is implanted without bone cement. After an implantation term of 1 year in animal experiment (dog), an adapted femur is compared with the contra-lateral normal femur. Strain gauges are used to determine bone strain under load. Further is determined external and internal construction change after endoprosthesis. The construction changes found are in connection with the changed bone strength. A cancellous change of bone at entire area of stem of prosthesis is called a ;metaphysation; of bone shaft.
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PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients.  相似文献   
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PURPOSE: To assess the impact of a diagnostic ladder including [(18)F]fluorodeoxyglucose positron emission tomography (PET) and lymphoscintigraphy guided sentinel node biopsy (LS/SNB) on neck treatment in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). PATIENTS AND METHODS: Prospectively, 62 patients with resectable T1-3 OOSCC underwent computed tomography (CT) and PET. Patients without neck uptake in PET were defined as cN0 and were accrued for LS/SNB. Results were correlated with histopathology. The traditional guidelines according to CT findings were compared to the actual regimen and the outcome. RESULTS: Sensitivity, specificity, validity, and positive and negative predictive value of PET versus CT were 72% v 89%, 82% v 77%, 79% v 80.5%, 62% v 61.5%, and 88% v 94.5% (not significant). Thirty-eight PET negative patients underwent LS/SNB. Sentinel lymph nodes were found in all 38 patients. Five patients had positive nodes (PET false-negatives) and underwent neck dissection (ND). Fifty-one neck sides in 36 patients who were CT-negative would have been treated with selective ND according to the guidelines, and at least 45 neck sides would have had to undergo extensive ND because of positive CT findings (96 of 124 neck sides). In contrast, PET in combination with LS/SNB spared 59 neck sides, and 41 of 124 neck sides actually underwent ND as a result of PET staging, LS/SNB, and intraoperative decision. After a median follow-up of 35 months, two patients (both cN+ve and pN+ve) suffered from neck relapses. CONCLUSION: Diagnostics using PET in combination with LS/SNB considerably reduced the number of extensive ND in OOSCC as compared to CT without locoregional hazard.  相似文献   
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PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account.  相似文献   
88.
Biliary atresia (BA) is one of the most frequent causes of neonatal cholestasis. Portoenterostomy is one therapeutic option in these patients with a success rate of 30-40%. To answer the question of therapy liver transplantation or Kasai operation - we analyzed 36 consecutive patients being followed in our center during the past 7 years. Two groups were formed: group I : patients developing cirrhosis within the first 2 years of life with the need for liver transplantation (n = 21). Group II: patients without need for transplantation within the first 2 years of life (n = 15). The two groups were compared regarding birth weight, age at diagnosis, age at Kasai-procedure, liver histology. The following biochemical parameters were analyzed at the time of diagnosis, 1 week and 5 weeks after Kasai: AST, ALT, gammaGT, and bilirubin. - Results: Clinical characteristics were similar in both groups. However BA was diagnosed in group I 8.2 weeks after birth compared to 5.6 wk in group II. gammaGT, ALT, AST, and bilirubin were similar in both groups at the time of diagnosis and 1 wk after Kasai. However 5 wk after Kasai gammaGT was 276 U/l in group I compared to 72 U/l in group II (p <0.001), bilirubin was 6.3mg/dl in group I compared to 2. 3mg/dl in group II (p <0.001). - Conclusion: Kasai operation before the 7th wk of life increases the success rate of this technique significantly. Children with cirrhosis at the time of diagnosis should be evaluated for primary liver transplantation. gammaGT and bilirubin 5 weeks after Kasai operation may be useful markers for the success of this procedure. Patients with a gammaGT > 100 U/l and a bilirubin level >5mg/dl should be followed closely and should be evaluated for liver transplantation early.  相似文献   
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