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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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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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It has been shown earlier that dilated cardiomyopathy can be associated withBorrelia burgdorferi infection.Here the authors present a case: a fifty-nine-year-old man who presented with dyspnea, oligoarthritis, paresthesia in both hands, and acrodermatitis chronica atrophicans. Upon further cardiologic exploration by cardiac catheterization and two-dimensional echocardiography (volume-length-area method), the patient exhibited an ejection fraction (EF) of 49%. Serology revealed IgG ELISA positive and IIFT 1:64 positive forB. burgdorferi. The patient received 2 × 150 mg roxithromycin orally for six weeks. Upon a second examination after termination of treatment (three months later), the patient presented with negativeB. burgdorferi serology and normal EF (70%). While cardiac manifestations thus apparently vanished, other symptoms persisted.This case may give new insight into mechanisms of action of macrolides againstB. burgdorferi (a field where information is inherently scant). One may, however, argue that in a well-perfused organ like the heart, tissue-activity of roxithromycin may suffice in order to unfold its activity againstB. burgdorferi.  相似文献   
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A series of water soluble aliphatic solutes were chosen for study. Fifty percent effective doses (ED50) to block propagated compound action potentials (AP's) were obtained by examining dose–response relations for each solute. All solutes used were liquids at room temperature and are typically used as solvents. The solutes studied were dimethylsulfoxide (DMSO), dimethylformamide (DMF), dimethylacetamide, acetone, and hexamethylphosphoramide (HMPA); the octanol/water partition coefficients for these test substances form an ordered sequence that increased 40-fold from DMSO to HMPA. AP's were recorded from desheathed frog sciatic nerves using the sucrose-gap technique; test solutes were added to Ringer's solution and applied externally to the nerve. ED50’s for the solutes could be predicted as a function of the molar volume (dV/dn), polarity (P), and the hydrogen bond acceptor basicity (β). Voltage-clamp experiments employing the vaseline-gap technique on single muscle fibers showed that each solute reduced Na+current with little change in their kinetics at all voltages studied. Experiments using DMSO or DMF showed that Na+channel block alone is insufficient to explain the respective ED50 values of AP block. Experiments conducted using a chloride transport-sensitive membrane fluidity assay, using rat pancreas secretory granules, suggested that each of the solutes act to increase membrane fluidity at doses below and above ED50 values. Light microscopic observations of fixed thick sections of whole nerves previously exposed to DMSO or DMF show structural changes; however, ED50 values cannot be simply explained by osmotic alterations of nerve structure. ED50’s are likely to be produced by a combination of effects including osmotically induced nerve structural changes, ion channel block, and fluidity changes. The toxicity (lethal doses or toxic concentrations) of each of these five solutes correlates well with the ED50 and could be predicted as a function of dV/dn, P, and β.  相似文献   
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