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71.
72.
F Bagnoli F Facchinetti F Petraglia D Parrini A R Genazzani 《Bollettino della Società italiana di biologia sperimentale》1981,57(17):1771-1776
beta Lipotrophin and beta Endorphin plasma levels have been measured in 35 newborns subdivided in 5 groups of 12, 24, 48, 72 and 168 hours of life, 10 umbilical mixed blood samples were also evaluated. After plasma extraction (3 ml) and G-75 Sephadex column chromatography, the peptides were measured by two specific RIAs. beta LPH and beta EP levels were high in umbilical cord plasma (241.0 +/- 43.3 and 70.0 +/- 8.5 pg/ml respectively). A progressive decrement was then observed until the 72th hour of life (28.1 +/- 13.2 and 8.7 +/- 4.8 pg/ml respectively) but the elevated levels found at 24th hour demonstrate an active synthesis and release from fetal and neonatal pituitary. After a slight and transient decreased activity during the first week of life, the statistically significant increase of both beta LPH and beta EP observed at seven day indicate that at this moment pituitary function is restored. 相似文献
73.
The XI International Rotifer Symposium was held during 11–18 March, 2006 at the National Autonomous University of Mexico Campus Iztacala located at the North Mexico City (Mexico). These triennial international meetings, first organized in Austria by Late Ruttner-Kolisko in September 1976, are gradually becoming the focal point of discussion and collaboration from rotifer workers across the world. The present XI symposium was attended by 125 participants from 20 nations. During this meeting, different themes of rotifer research from morphology to molecular biology were considered. In addition, there were four invited lectures and four workshops covering different themes of the symposium. During the last 30 years, rotifer research has witnessed gradual shift from the conventional morphological taxonomy to molecular and evolutionary systematics. While the basic rotifer ecological studies continue today, applied areas such as ecotoxicology and aquaculture have taken key roles in the recent meetings. The international rotifer meetings provide ample opportunities not only for exchange of ideas and recent research, but also for material and in establishing inter-personal relationships. Over the last 30 years, the number of participants attending the rotifer meetings has increased. 相似文献
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Abstract: The family Phylloporinidae was introduced in the late 19th century to accommodate a small number of Palaeozoic bryozoan genera characterized by irregularly fenestrated colonies generated by anastomosis of unilaminate branches. Among the first named of these genera were Chasmatopora Eichwald, 1855 and Phylloporina Ulrich in Foerste, 1887. The two names have been variously in fashion, and there has been confusion about whether they are subjective synonyms or are distinct genera. This taxonomic confusion has been due in large part to whether the single species (Retepora angulata Hall, 1847) assigned to Phylloporina in Foerste (1887) or the species that Ulrich intended (Retepora trentonensis Nicholson, 1875) is the type species and also because of lack of sufficient information about Foerste’s material to characterize it well. We here redescribe the pertinent species, erect the new species Chasmatopora foerstei for the species that Foerste incorrectly assigned to Phylloporina angulata (Hall), and suggest that Retepora trentonensis Nicholson be retained as type species of Phylloporina based on prevailing usage, until the issue is settled by the International Commission on Zoological Nomenclature. 相似文献
77.
Different patterns of central and peripheral beta EP, beta LPH and ACTH throughout life 总被引:1,自引:0,他引:1
F Facchinetti F Petraglia G Nappi E Martignoni G Antoni D Parrini A R Genazzani 《Peptides》1983,4(4):469-474
The aim of the present study was to evaluate the relationship between central and peripheral concentrations of proopiocortin-related peptides in different periods of life. One hundred and eighty-nine plasma samples from normal subjects (18-87 years) obtained in basal conditions, and 20 cerebrospinal fluid (CSF) samples obtained by lumbar puncture from healthy volunteers (18-75 years) were studied. beta Lipotropin (beta LPH), beta endorphin (beta EP) and ACTH were measured by specific RIA after silicic acid plasma extraction and gel chromatography (beta LPH and beta EP). No sex differences were found in the patterns of the three peptides either in the plasma or in CSF. In the plasma samples, both beta LPH and beta EP concentrations showed a pattern throughout life which was expressed by a paraboloid function with the lowest values found in young and old subjects and with peaks at 51.3 and 48.2 years, respectively. On the contrary, ACTH values failed to be represented by a significant linear or curvilinear regression and presented only a slight decrease in subjects over 75 years of age. CSF levels of beta LPH were significantly lower in 45-76 year old subjects (18.8 +/- 12.6 fmol/ml, M +/- SD) than in 18-44 year old subjects (34.5 +/- 15.8; p less than 0.05), as were those of beta EP (elderly: 41.2 +/- 19.7; young: 94.2 +/- 36.7; p less than 0.05), which showed a significantly linear inverse correlation with age (r = 0.6062, p less than 0.01). These CSF samples did not show any ACTH variations connected with age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
Large‐scale environmental changes create challenges for conservation of wildlife, particularly in fenced, insular protected areas where many wildlife populations persist. Moreover, large mammalian herbivores inhabiting spatially and temporally heterogeneous environments face the challenge of securing highly variable forage resources. Mixed feeders like the eland (Taurotragus oryx) can switch between browse and grass, but the cues that elicit that switch are not well understood. We investigated the seasonal diet shift of eland confined to a small fenced reserve and the role of greenness to elicit that shift. Eland changed from a diet in the wet season, consisting of grasses and browse found in woodland and grassland vegetation types, to a diet in the dry season dominated by the greenest browse species still available in woodland vegetation types, as greenness of dry season forage decreased. Our results suggest that eland switch from browsing to grazing in response to phenophase of the grass sward, which could explain the varying selection of grasses versus browse observed across the species range. 相似文献
79.
Caren Rodriguez-Medina Craig A Atkins Anthea J Mann Megan E Jordan Penelope MC Smith 《BMC plant biology》2011,11(1):36
Background
Members of the legume genus Lupinus exude phloem 'spontaneously' from incisions made to the vasculature. This feature was exploited to document macromolecules present in exudate of white lupin (Lupinus albus [L.] cv Kiev mutant), in particular to identify proteins and RNA molecules, including microRNA (miRNA). 相似文献80.
Ferry Cornelissen Adriana MC Mus Patrick S Asmawidjaja Jan Piet van Hamburg Joel Tocker Erik Lubberts 《Arthritis research & therapy》2009,11(6):1-13