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31.
D Schmidt D Harms H Jürgens 《Zentralblatt für allgemeine Pathologie und pathologische Anatomie》1989,135(3):257-268
In view of the personal observation that malignant peripheral neuroectodermal tumours (MPNT) can present different histological growth patterns, 41 cases of MPNT were histologically and immunohistochemically studied. The median age of the 41 patients was 15 years (range: 9 months - 23 years). There were 27 males and 14 females. Most tumours (23/41) were located in the thoracopulmonary region. In 31/41 cases there was bone as well as soft tissue involvement. The following histopathological patterns were found: Ewing's sarcoma-like (n = 7), atypical Ewing's sarcoma-like (n = 4), neuroblastoma-like (n = 8), rhabdomyosarcoma-like (n = 8), and hemangiopericytoma-like (n = 1). In 2 cases combined patterns were noted, one tumour being characterized by neuroblastoma-like and Burkitt's lymphoma-like features. Most cases of MPNT differed from the cytological features of typical Ewing's sarcoma in that they contained hyperchromatic nuclei with distinct nucleoli. Some reticulin fibrils were found in between the cells of some cases. Immunohistochemically, 19/23 cases reacted positively to vimentin, 29/32 to neuron specific enolase (NSE), 16/28 to protein S-100, and 1/9 to glial fibrillary acidic protein. 12/24 cases reacted positively to NSE and protein S-100. Neurofilaments and desmin were not found in the formalin fixed material of the present study. The results show that most cases of MPNT can be distinguished from typical Ewing's sarcoma by cytological and histological findings. Differential diagnosis from atypical Ewing's sarcoma, neuroblastoma, and rhabdomyosarcoma is possible by immunohistochemistry. 相似文献
32.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
33.
Analysis for nonextractable (bound) residues of pentachlorophenol in plant cells using a cell wall fractionation procedure 总被引:1,自引:0,他引:1
When plant cell cultures or aseptically grown wheat plants were treated with [14C]-pentachlorophenol (PCP) a major part of the label was found in a nonextractable or "bound" residue fraction. Soluble polar conjugates participated in the formation of these residues which were mainly located in the plant cell walls. By a sequential fractionation procedure using enzymatic and chemical methods, 90 to 95% of the bound radioactivity could be attributed to individual cell wall components. The 14C label from PCP was found mainly in hemicellulose, lignin, and protein fractions. Associations of hemicellulose with PCP derivatives with molecular weights up to 500,000 were purified to constant specific radioactivity. Hydrolysis of this fraction released 32% PCP and other unidentified products. 相似文献
34.
Sean Cowlishaw Olivia Metcalf Tracey Varker Caleb Stone Robyn Molyneaux Lisa Gibbs Karen Block Louise Harms Colin MacDougall H. Colin Gallagher Richard Bryant Ellie Lawrence‐Wood Connie Kellett Meaghan O'Donnell David Forbes 《Journal of traumatic stress》2021,34(1):46-55
Anger is an important dimension of affect and a prominent feature of posttraumatic mental health, but it is commonly overlooked in postdisaster settings. We aimed to examine the distribution and implications of significant anger problems in the aftermath of a natural disaster, via analyses of Beyond Bushfires survey data from 736 residents of rural communities 5 years after the 2009 Black Saturday bushfires in Victoria, Australia. Assessments included the five‐item Dimensions of Anger Reaction (DAR‐5) scale along with measures of PTSD, depression, and significant mental illness, and indicators of life satisfaction, suicidality, hostile aggressive behavior, and violence exposure. The results indicated that approximately 10% of respondents from areas highly affected by the bushfires scored above the provisional cutoff criteria for significant anger problems on the DAR‐5, which was a more than 3‐fold increase, OR = 3.26, relative to respondents from areas of low‐to‐moderate bushfire impact. The rates were higher among women, younger participants, and those who were unemployed, and co‐occurred commonly, although not exclusively, with other postdisaster mental health problems. Anger problems were also associated with lower life satisfaction, β = ?.31, an 8‐fold increase in suicidal ideation, OR = 8.68, and a nearly 13‐fold increase in hostile aggressive behavior, OR = 12.98. There were associations with anger problems and violence exposure, which were reduced when controlling for covariates, including probable PTSD. The findings provide evidence indicating that anger is a significant issue for postdisaster mental health and should be considered routinely alongside other posttraumatic mental health issues. 相似文献
35.
E. Herting O. Gefeller Ch. P. Speer K. Harms H. L. Halliday T. Curstedt B. Robertson 《European journal of pediatrics》1994,153(11):842-849
Within a randomized European multicentre trial the time of onset, severity and progression of intracerebral haemorrhages (ICH) were investigated prospectively by serial cranial ultrasonography in 343 ventilated infants with severe respiratory distress syndrome (RDS) following instillation of single or multiple doses of a natural porcine surfactant (Curosurf). In 148/343 infants (43%) ICH was diagnosed (grade I or II: 22%, grade III or IV: 21%). In 26 cases (8%) ICH was present on the ultrasound scan prior to surfactant instillation at a median age of 6h. Incidence and severity of ICH was similar after single- or multiple-dose surfactant treatment. Using a logistic regression model the following risk factors predictive of ICH were defined: low birth weight, allocation to certain hospitals, vaginal delivery, Apgar score6, rectal temperature on admission 36°C, primary anaemia, acidosis prior to treatment, RDS grade IV in pre-treatment chest films and poor response to surfactant treatmentOur study provides supportive evidence that multiple doses of Curosurf do not increase the risk for ICH as compared to single-dose administration.A preliminary report of this work was presented at 8th International Workshop on Surfactant Replacement, Oslo, Norway, May 21 1993. The study was supported by grants of the German government (BMFT 93 607 27) and the German Research Council (Deutsche Forschungsgemeinschaft He 2072: 1–2). The surfactant used in the trial was prepared ang tested in Stockholm with the skilful technical assistance of Elin Arvesen, Bim Linderholm. Eva Lundberg, Gunhild Nilsson and Petru Popa (supported by the Swedish Medical Research Council (Project No. 3351) and Oscar II:s Jubileumsfond)Dedicated to the memory of Edgar (Eddi) Laufkötter, one of the most active trial collaborators, who died under tragic circumstances on April 10, 1994. 相似文献
36.
37.
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
38.
39.
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.相似文献
40.
Lang T Kappler M Dietz H Harms HK Bertele-Harms R 《European journal of medical research》2000,5(3):110-114
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