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271.
J S Fortunato M J Pinheiro M C Monteiro M A Rodrigues I Amaral 《Journal of nuclear biology and medicine (Turin, Italy : 1991)》1991,35(2):105-110
The platelet (Plt) contribution to cardiovascular events triggered by adrenergic stress is supported by some experimental and necropsy data, but a cause and effect link and mechanism have not yet been clearly demonstrated. Adrenergic stress was simulated by three successive adrenaline (A) injections (80 micrograms/kg) in anesthetized dogs previously infused with indium111 labelled Plt (111In-Plt) for a gamma-camera study. Adrenaline induced an acute and significant decrease in the Plt aggregation ratio (PAR) and a parallel decrease in the Plt count as well as in the circulating 111In-Plt, mirroring a significant and persistent Plt sequestration mainly in the liver and spleen. The long-lasting and significant decrease in the circulating Plt count observed 15 min after each A injection can be explained by a persistent retention of Plt. Further studies are in progress in order to disclose if this corresponds to platelet microaggregate embolization in microvessels of the organs so far analysed. If this postulate can be confirmed the hypothesis of an adrenergic stress triggering of ischemic events will be justified. 相似文献
272.
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274.
L Milewich S J Fortunato M Barris M C Maberry L C Gilstrap P C MacDonald 《Journal of steroid biochemistry》1990,35(1):67-75
The specific activity of 17 beta-hydroxysteroid oxidoreductase (17 beta-HSOR) in human umbilical cord arterial serum has been reported to be similar to that of maternal serum and 5- to 15-times higher than that of cord venous serum. Based on these findings, it was proposed that 17 beta-HSOR in cord arterial serum arises from fetal tissue sources other than placenta. In the course of studies of the role of 17 beta-HSOR in the modulation of bioactive estrogen levels in the human fetus, we determined that: (i) the specific activity of 17 beta-HSOR in maternal serum is 2.1- to 55-times higher than that in either umbilical cord venous serum or cord arterial serum; (ii) the specific activity of 17 beta-HSOR in umbilical cord venous and cord arterial sera are similar; (iii) anti-human placental cytosolic 17 beta-HSOR antibody inactivates the 17 beta-HSOR in maternal, umbilical cord arterial, and cord venous sera but not in maternal or fetal erythrocytes; (iv) the specific activity of 17 beta-HSOR in maternal serum (expressed per mg protein) is higher than that in umbilical cord serum and maternal and fetal erythrocytes, and is approximately 700-times lower than that of the placental microsomal enzyme; (v) the preferred cofactor for maternal serum 17 beta-HSOR is NADP+; (vi) 17 beta-HSOR is associated with the high speed supernatant fraction of maternal serum rather than with the particulate fraction; and, (vii) the patterns of binding of [3H]estradiol-17 beta to proteins in maternal and umbilical cord arterial sera and those of 17 beta-HSOR activity, determined in corresponding fractions obtained after sucrose density gradient centrifugation, are approximately coincidental at S20, omega 4.6-5. The findings of higher 17 beta-HSOR levels in maternal serum compared with umbilical cord arterial serum and the inactivation of the cord arterial serum enzyme by an antibody that recognizes human placental cytosolic 17 beta-HSOR is suggestive that 17 beta-HSOR in cord arterial serum is of placental origin. 相似文献
275.
276.
Alessandra Mascaro Massimo Farina Raffaella Gigli Carlo E Vitelli Lucio Fortunato 《World journal of surgical oncology》2010,8(1):1-17
A tremendous improvement in every aspect of breast cancer management has occurred in the last two decades. Surgeons, once solely interested in the extipartion of the primary tumor, are now faced with the need to incorporate a great deal of information, and to manage increasingly complex tasks. As a comprehensive assessment of all aspects of breast cancer care is beyond the scope of the present paper, the current review will point out some of these innovations, evidence some controversies, and stress the need for the surgeon to specialize in the various aspects of treatment and to be integrated into the multisciplinary breast unit team. 相似文献
277.
N Marques S C Afeche A A Benedito-Silva J Cipolla-Neto G Fortunato L A Paludetti E G Recine C Schott L S Menna-Barreto 《Chronobiologia》1988,15(3):235-241
We describe the didactic experience of graduate and post-graduate courses on chronobiology in S?o Paulo, Brazil. 相似文献
278.
Galactia dimorphophylla, a new species from northeastern Argentina and northern Uruguay, is described and illustrated. This new species is assigned
to sect. Odonia. A table distinguishing it from similar species in Southern South America is presented, and its relationships and distinguishing
characters including karyological features are discussed. 相似文献
279.
Significant amounts of wealth have been exchanged as part of marriage settlements throughout history. Although various models
have been proposed for interpreting these practices, their development over time has not been investigated systematically.
In this paper we use a Bayesian MCMC phylogenetic comparative approach to reconstruct the evolution of two forms of wealth
transfers at marriage, dowry and bridewealth, for 51 Indo-European cultural groups. Results indicate that dowry is more likely
to have been the ancestral practice, and that a minimum of four changes to bridewealth is necessary to explain the observed
distribution of the two states across the cultural groups.
A preliminary version of this paper was presented at the 16th meeting of the Human Behavior and Evolution Society (HBES), Berlin 2004. Mark Pagel and Andrew Meade provided the software,
the coded linguistic data, and valuable advice on their use. LF is funded by Fondazione Ing. Aldo Gini (Italy), the ESRC (UK),
and the UCL Graduate School (UK). Five anonymous reviewers provided helpful comments.
The authors are based at the Department of Anthropology of UCL and members of the AHRC Centre for the Evolutionary Analysis
of Cultural Behaviour (CEACB). LF is studying towards a PhD, CH is a CEACB Senior Research Fellow, and RM is Professor of
Evolutionary Anthropology. 相似文献