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D. Grant Richards Kevin G. Whithear Peter C. Scott Robin B. Gasser 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(2):156-159
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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Ronald A. Kramp Nathalie Caron Jacqueline Genard Christelle Lejeune Egils Gulbis Arnold Herman 《European journal of pharmacology》1997,330(2-3):165-176
Renal hemodynamics were studied using an electromagnetic perivascular flow sensor in anesthetized rats injected i.v. with vehicle, 5 or 10 mg/kg body weight (b.w.) sulindac. No hemodynamic changes occurred with vehicle (n=6), but mean arterial pressure was significantly decreased (by 15 mmHg) with sulindac (n=12). In the 5 mg/kg b.w. sulindac group (n=7), renal blood flow progressively and significantly increased from 7.88±0.36 to 8.98±0.58 ml/min, except during concomitant intrarenal infusion of 3 mg/kg b.w. per h proadifen (n=7). The pressure limits for efficient and no renal blood flow autoregulation remained unchanged (approx. 100 and 80 mmHg, respectively). In the 10 mg/kg b.w. sulindac group (n=5), renal blood flow did not change but autoregulatory pressure limits were lowered by 10 mmHg 2 h after treatment (P<0.025). Also, Na+ retention was marked. Prostanoid excretion in urine was significantly reduced with either dose but basal plasma renin activity was not (about 8 ng/ml per h; n=15). When plasma renin activity was enhanced after a reduction in renal perfusion pressure (n=21), it was decreased from 11.5±1.2 to 7.4±0.2 ng/ml per h only by 10 mg/kg b.w. sulindac (P<0.05; n=6). In conclusion, differential effects of sulindac on renal hemodynamics, Na+ excretion and plasma renin activity were demonstrated. Renal hemodynamic changes could be related in part to the cytochrome P-450 arachidonic acid pathway. 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
6.
Minerva Giménez y Ribotta Christelle Roudet Françoise Sandillon Alain Privat 《Brain research》1996,707(2):245
The synaptic connections established by grafted noradrenergic (NA) neurons into the lesioned adult rat spinal cord were analysed using immunocytochemistry at the electron microscopic level. An embryonic cell suspension of the locus coeruleus region from E-13 rat embryos was transplanted into the spinal cord following either: (1) spinal cord transection or (2), partial selective denervation by 6-hydroxy dopamine (6-OH DA). One month after grafting, the NA-neurons established, in the two models, an innervation pattern similar to that found in the intact spinal cord. In both models, the transplanted NA-immunoreactive neurons formed extensive synaptic contacts with dendrites, spines and perikarya. The proportion of axodendritic and axospinous contacts was inverse in the two models. The first model thus reproduced more closely the normal synaptic pattern prefering dendritic targets, which could correspond to a better integration of the graft. In the second model, a partially NA-denervated spinal cord, there existed a competition between residual intrinsic and grafted neuron-derived fibres, which presumably affects synaptogenesis. In conclusion, the present study illustrate the complexity of cell interations conducting to the formation of a specific circuitry. Recognition phenomenon are likely modulated by space constraints, which ultimately shape-up the geometry of synaptic contacts. 相似文献
7.
Binet I; Bock A; Vogelbach P; Gasser T; Kiss A; Brunner F; Thiel G 《Nephrology, dialysis, transplantation》1997,12(9):1940-1948
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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