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Coccidiosis of chickens, caused by species of Eimeria (Protozoa, Apicomplexa), is an intestinal disease of major economic importance worldwide. In the present study, the reproductive characteristics of a precocious line (designated E. tenella Rt3+15) from Australia were investigated in chicken embryos and the implications of the findings briefly discussed.  相似文献   
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Zusammenfassung Entstehung und Progression von Tumoren werden durch Funktionsst?rungen von spezifischen Genen gesteuert. Obwohl das Prostatakarzinom zu den h?ufigsten Tumoren geh?rt, ist über die bei diesem Tumor involvierten Gene wenig bekannt. Zytogenetische und molekulare Untersuchungen haben gezeigt, da? chromosomale Deletionen besonders h?ufig das Y-Chromosom, 7q, 8p, 10q, 13q, 16q und 17p betreffen. Diese Loci dürften für das Prostatakarzinom relevante Tumorsuppressorgene enthalten. H?ufige DNS-Sequenzvermehrungen von Chromosom 7, 8q und 11q deuten auf die Lokalisation von m?glichen Onkogenen hin. Bereits heute bestehen Anhaltspunkte für eine Prognoserelevanz genetischer Ver?nderungen. Der Nachweis von Polysomien in Prim?rtumoren deuten auf eine ungünstige Prognose hin. Eine Amplifikation des Androgenrezeptors spricht für einen Hormontherapie-resistenten Tumor, welcher m?glicherweise besonders gut auf eine totale Androgenblockade ansprechen wird. Die Identifikation der alterierten Gene und die Entschlüsselung ihrer Funktion k?nnte in Zukunft zu deutlich verbesserten Behandlungsstretegien für Patienten mit Prostatakarzinom führten.   相似文献   
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Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:9,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
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Outcome in emotionally related living kidney donor transplantation   总被引:9,自引:5,他引:4  
Background. The growing shortage of cadaver kidneys, the limited possibilities to expand the living related donor pool and the good results obtained in our centre with poorly matched cadaver kidneys, led us in 1991 to begin accepting highly motivated, unrelated, living kidney donors who had a strong emotional bond with the recipients. Methods. Between 1 January 1991 and 1 January 1996, 46 potential living kidney donors and their emotionally related recipients were evaluated. Twenty-three cases were accepted for renal transplantation after thorough somatic and psychological evaluation. The mean post-transplant follow-up until 1 April 1996 was of 28±3 months. Compatible blood groups and a negative cross-match were mandatory, but no minimal HLA matching was required. Results. There was a 50% drop-out rate following the initial screening. The main reasons for not performing transplantation were immunological contraindications in 39% of the cases, somatic in 30.5%, psychological in 26% and socioeconomic in 4.5%. In the accepted group of recipients, 48% (11/23) received transplants without chronic dialysis. Donor survival was 91%; two deaths unrelated to nephrectomy occurred 1 year after donation. The 2-year actuarial recipient and graft survivals were 100% and 91% respectively, compared to 99% (recipients) and 93% (grafts) in the non-HLA-identical living related kidney transplant group, and to 93% (recipients) and 83% (grafts) in the cadaver kidney transplant group. Recipient rehabilitation was completed after 4±1 months. Emotionally related donors returned to work 5±2 weeks after nephrectomy, and no donor regretted his decision, even in the case of failure. Conclusions. Kidney transplantation from emotionally related living donors represents a valuable option, allowing more patients with end-stage renal disease to avoid chronic dialysis. Recipient and graft outcome were superior to cadaver kidney transplantation. Motivated and emotionally related donors should be allowed to donate one of their kidneys provided that they are carefully selected and thoroughly informed.  相似文献   
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Winkler  ML; Olsen  WL; Mills  TC; Kaufman  L 《Radiology》1987,165(1):203-207
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.  相似文献   
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