Showing papers by "University of Florence published in 1984"
TL;DR: This tumor is viewed as a poorly differentiated carcinoma, situated morphologically and biologically in an intermediate position between the well-differentiated (papillary and follicular) and the totally undifferentiated thyroid tumors.
Abstract: Twenty-five cases of a distinctive type of thyroid carcinoma are presented. The key microscopic features are: formation of solid clusters ("insulae") of tumor cells containing a variable number of small follicles; small size and uniformity of the tumor cells; variable, but consistently present mitotic activity; capsular and blood vessel invasion; and frequent necrotic foci, sometimes leading to the formation of "peritheliomatous" structures. Metastases to regional lymph nodes, lung, and bones are common, and these often lead to the patients' death. We view this tumor as a poorly differentiated carcinoma, situated morphologically and biologically in an intermediate position between the well-differentiated (papillary and follicular) and the totally undifferentiated thyroid tumors. We believe that it is closely related, if not identical, to the tumor type described by Langhans in 1907 as "wuchernde Struma."
471 citations
TL;DR: The hypothesis that adenosine modulates the electrophysiological responses to stimulation of stratum radiatum through a reduction of the release of the excitatory amino acids aspartate and glutamate is supported.
354 citations
TL;DR: In this paper, a model for the post-Tortonian evolution of the whole Central Mediterranean area is presented, which can be classified into three main regions: the Tyrrhenian Sea, the Pelagian block and the Ionian block.
158 citations
TL;DR: The presence of quinolinic acid (2,3-pyridinedicarboxylic acid, QA) in the rat brain has been demonstrated using a mass-spectrometric method and support the idea that QA merits special attention as a potential transmitter and as an endogenous excitotoxin in brain.
135 citations
TL;DR: By increasing the control horizon length, the proposed algorithm, referred to by the acronym MUSMAR, is shown to be a natural generalization of standard self-tuning controllers and closely approximates a steady-state LQG controller inheriting the intrinsic robustness of LQGs design.
117 citations
TL;DR: New information is provided concerning the possible mechanism of cluster headache attacks and a new therapeutic approach is suggested that is comparable to ergotamine tartrate treatment.
Abstract: The pain relieving effect of somatostatin treatment during 72 attacks of cluster headache in 8 male patients was compared to treatment with ergotamine or placebo in a double-blind study. Infusion of somatostatin (25 μg/min for 20 min i.v.) reduced the maximal pain intensity and the duration of pain significantly compared to placebo treatment, and to a degree comparable to ergotamine tartrate treatment (250 μg i.m.). The results obtained provide new information concerning the possible mechanism of cluster headache attacks and suggest a new therapeutic approach.
112 citations
TL;DR: The cortex contained the highest concentration of QUIN in the three species studied and during the rat development the concentration of this molecule increased and unusually high amounts of it were found in approximately 50% of 30-month-old rats.
107 citations
TL;DR: The data indicate that GM1 treatment maintains the number of dopaminergic cell bodies in the substantia nigra after hemitransection by protecting against retrograde neuronal degeneration.
106 citations
TL;DR: In this article, the authors investigated the Tertiary volcanism of Eastern Macedonia and Western Thrace (Greece) developed in association with the sedimentary basin which formed, from Eocene to Oligocene, along the southern margin of the Rhodope Massif.
Abstract: The Tertiary volcanism of Eastern Macedonia and Western Thrace (Greece) developed in association with the sedimentary basin which formed, from Eocene to Oligocene, along the southern margin of the Rhodope Massif. The volcanic products, ranging in composition from basaltic andesites to rhyolites, show an overall calc-alkaline orogenic affinity, while chemical characteristics identify different groups of rocks, probably reflecting minor differences among parent magmas. The observed evolution within any group of rocks is compatible with fractional crystallization processes acting on relatively shallow magma bodies. The Sr isotopic composition of rhyolitic member shows an initial87Sr/86Sr ratio comparable with that of basaltic andesites, reinforcing the hypothesis of a crystal/liquid line of descent. Geochemical and petrographic evidence, on the whole, suggests that the investigated orogenic association developed on an active continental margin characterized by a relatively thick crust, acting as a density filter for the basic magmas and facilitating their storage and fractionation within the crust itself. Minor contamination by interaction with host materials may also have occurred. Stratigraphic and K/Ar geochronological data indicate that the volcanic activity started in Upper Eocene and reached its maximum development in Upper Oligocene. From Lower Miocene, the volcanism shifted southward in the Central Aegean area and in part of Western Anatolia, coming to an end by Middle Miocene. The southward migration of the volcanic front has been interpreted as a consequence of the increase in the dipping of the Benioff zone, due to the decrease of penetrative strength after the main phase of continental collision.
90 citations
TL;DR: The rationale, design, and performance of a high-resolution Fourier transform spectrometer are discussed and the instrument was employed in the measurement of stratospheric emission in the 7–90-cm−1 spectral interval with a 0.0033- cm−1 resolution from a balloon-borne platform at ~40-km altitude.
Abstract: The rationale, design, and performance of a high-resolution Fourier transform spectrometer are discussed. The instrument was employed in the measurement of stratospheric emissionin the 7–90-cm−1 spectral interval with a 0.0033-cm−1 resolution (unapodized) from a balloon-borne platform at ~40-km altitude.
84 citations
TL;DR: Trace element data are reported in 21 lava samples from the Alban Hills, one of the most important volcanic complexes of the Roman comagmatic region as discussed by the authors, consisting mostly of tephritic leucitites with minor phonolitic tephrites and tephrite phonolites emplaced during two distinct phases of activity, separated by a caldera collapse.
Abstract: Trace element data are reported in 21 lava samples from the Alban Hills, one of the most important volcanic complexes of the Roman comagmatic region. The samples consist mostly of tephritic leucitites with minor phonolitic tephrites and tephritic phonolites emplaced during two distinct phases of activity, separated by a caldera collapse.
TL;DR: The internal lherzolites, representing the base of the Northern Apennine ophiolite sequences, show a significant residual character and are generally associated with normal MORB.
TL;DR: In this paper, a series of dinuclear copper-(II) complexes with oxamidato, oxamato and oxalato ligands were synthesized for the purpose of studying the influence of the ligands on the extent of the antiferromagnetic coupling between the two metal ions.
TL;DR: This chapter presents a critical overview of the literature available on lonidamine and related class of these compounds and also of the perspectives of research in progress, and the most promising derivative of the series is tolnidamine.
Abstract: Publisher Summary This chapter presents a critical overview of the literature available on lonidamine and related class of these compounds and also of the perspectives of research in progress. Present studies are focused on the therapeutic activity of lonidamine in cancer conditions and in their use as a tool to investigate some specialized energy-yielding processes. Available data indicate that lonidamine is useful in cancer therapy alone or combined with other agents that increase the response of the cancer cells to lonidamine. Information on the mechanism of action of indazolecarboxylic acids has also renewed interest in their potential use as male contraceptives; in this connection, the most promising derivative of the series is tolnidamine.
TL;DR: In this article, Creutz-Taube et al. made a point sur le modele de recouvrement angulaire, and calculated de couplage spin-orbite.
TL;DR: The possibility that GM1 may exert its stimulatory effect on HACU independently of the well‐known effect of gangliosides on neuronal sprouting is discussed.
Abstract: The effect of repeated administrations of GM1 monosialoganglioside on high-affinity choline uptake (HACU) was investigated in the cerebral cortex of rats with a unilateral electrolytic lesion of the nucleus basalis magnocellularis. In saline-treated rats, 4 days after lesion, a 38% and 14% decrease in HACU-activity was found in the ipsilateral frontal and parietal cortex, respectively. A spontaneous recovery of HACU activity occurred within the next 20 days. In rats receiving daily injections of GM1 from the day of operation, no significant decrease in HACU activity was found in the lesioned hemisphere 4 days after the lesion. In contrast a 25% increase in HACU activity in the frontal area of the opposite hemisphere was detected. No effect of GM1 treatment could be seen on days 10 or 20 after lesion. The possibility that GM1 may exert its stimulatory effect on HACU independently of the well-known effect of gangliosides on neuronal sprouting is discussed.
TL;DR: The presence of 4-androsten-3,17-dione within the incubation products suggests that the enzymatic preparation contains at least 3 beta-hydroxysteroid: NAD oxydoreductase and 3-oxosteroid-5-4-ene isomerase.
TL;DR: In this article, a mixed approach of depth-first search-dynamic programming (DFLP) and the Ahrens-Finke algorithm was proposed to solve the Subset-Sum Problem (SSP).
Abstract: Given n items, each having a weight wi, and a container of capacity W, the Subset-Sum ProblemSSP is to select a subset of the items whose total weight is closest to, without exceeding, W.
The paper presents a mixed approach depth first search-dynamic programming to the exact solution of the problem. An extensive computational experience is presented, comparing the proposed algorithm with that of Ahrens-Finke, as well as with the Balas-Zemel algorithm for large problems. Both "easy" and "hard" problems with values of n up to 10,000 are considered.
TL;DR: In this paper, the steric reaction of dicarboxylic acids was studied in the homogeneous phase in the presence of H4Ru4(CO)8(PBu3)4.
TL;DR: The results suggest that the instability of angina is associated with functional changes not confined to the coronary vasculature.
TL;DR: It is suggested that ageing modifies atrialRefractoriness in a non-uniform manner inducing a progressive increment of dispersion of atrial refractoriness.
TL;DR: In this paper, an equation was derived to describe the water 1H T1− NMR values when water is interacting with high-spin cobalt(II) with S = 3 2 under slow rotation conditions.
TL;DR: Comparison of the pattern of changes ofPC:Ag levels with those of fibrinogen, orosomucoid and prothrombin in 21 patients during the postoperative period and in 20 patients with active rheumatoid arthritis ruled out the possibility that high PC:Ag is non-specific, acute-phase reaction to inflammation, tissue injury or neoplastic growth.
Abstract: Protein C, an antithrombotic protein, was measured immunologically in 299 patients with clinical conditions associated with a high frequency of venous or arterial thromboembolism. The mean protein C antigen (PC:Ag) level was high for 48 patients with ischemic heart disease and, to a lesser extent, for 95 diabetics. In 28 patients with thrombotic strokes, 48 patients with proximal deep-vein thrombosis and in 80 patients with localized or metastatic tumors, mean PC:Ag was normal. Comparison of the pattern of changes of PC:Ag levels with those of fibrinogen, orosomucoid and prothrombin in 21 patients during the postoperative period and in 20 patients with active rheumatoid arthritis ruled out the possibility that high PC:Ag is non-specific, acute-phase reaction to inflammation, tissue injury or neoplastic growth. Therefore, high PC:Ag might be specifically related to the thrombotic tendency of these patients, but the mechanism of such a relationship remains to be clarified.
TL;DR: It is suggested that the depressant effect of the opioid peptides was due to stimulation of presynaptic inhibitory opiate receptors on adrenergic nerve terminals of the heart, and that the potentiation of the sympathetic response by morphine and methadone was probably attributable to an unspecific inhibitory effect on the neuronal uptake of noradrenaline.
Heidelberg University1, University of Kansas2, Lund University3, University of South Carolina4, California Institute of Technology5, University of Cape Town6, Carnegie Mellon University7, Polish Academy of Sciences8, University of Erlangen-Nuremberg9, University of Florence10, University of Hamburg11, Harvard University12, Radboud University Nijmegen13, Princeton University14, Stanford University15, University of Würzburg16
TL;DR: The e + e − − -storage ring DORIS II provides polarized beams with polarizations up to 80% in the energy range of the ϒ ′ meson as discussed by the authors.
TL;DR: In this article, the magnetic field amplitude and direction are recovered with good accuracy when these quantities are constant in the model atmosphere, and, in those cases where te magnetic field vector is supposed to vary monotonically with optical depth, the values recovered are always intermediate between the values corresponding to the top and bottom of the atmosphere.
Abstract: The inversion routine proposed by Aueret al. (1977), for the determination of vector magnetic fields from Stokes profiles, has been generalized to include magneto-optical and damping effects. Synthetic profiles have then been generated from a sunspot model atmosphere accounting for the depth variation of the relevant physical parameters such as the magnetic field amplitude, inclination angle, etc...., each variation being considered one at a time. Alfven waves and magnetic inhomogeneities over the field of view have also been considered. These synthetic profiles have been presented to the inversion routine. The results of the fits show that the magnetic field amplitude and direction are always recovered with good accuracy when these quantities are constant in the model atmosphere, and, in those cases where te magnetic field vector is supposed to vary monotonically with optical depth, the values recovered are always intermediate between the values corresponding to the top and bottom of the atmosphere. Moreover, we found that the differences between synthetic and best-fit profiles are able to characterize, in many cases, the particular physical situation considered.
TL;DR: In this paper, the uniform geometrical theory of diffraction (UTD) together with a generalized spectral extension arc was applied to calculate the highfrequency scattering by two nearby edges illuminated at grazing incidence.
Abstract: The uniform geometrical theory of diffraction (UTD) together with a generalized spectral extension arc applied to calculate the high-frequency scattering by two nearby edges illuminated at grazing incidence. Several examples arc considered which involve the diffraction by a pair of parallel edges where one edge is illuminated by the shadow boundary field of the other. Expressions for the diffracted field have been obtained for plane, cylindrical, and spherical wave illumination with either the electric or magnetic field perpendicular to the edges. Extensive numerical results are given for a pair of staggered parallel half-planes, a thick screen, and a rectangular cylinder. Comparisons with the results calculated by other techniques are also presented to demonstrate the accuracy of the method.
TL;DR: It is possible that, in addition to sympathetic-adrenergic and parasympathetic-cholinergic nerves, VIPergic nerves may participate in the autonomic nervous control of thyroid function.
Abstract: Neurons containing vasoactive intestinal peptide (VIP) have been found to reach thyroid follicular cells in man and other mammals. Human thyroid cells in culture were exposed to different concentrations of VIP and TSH, and thyroid cell activation was assessed by measurements of cAMP accumulation. VIP exerted a dose-dependent activation, and this thyroid-stimulating effect was more rapid and short-acting than that of TSH. At low concentrations of the two agents, their effects were additive, but they seemed to initiate their effects via different receptors, since polyphloretin phosphate inhibited the effect of TSH but not that of VIP. Moreover, antiadrenergic and anticholinergic agents did not influence thyroid activation by VIP. In addition to cAMP activation in cell cultures, VIP stimulated T4 release from human thyroid slices. It is possible that, in addition to sympathetic-adrenergic and parasympathetic-cholinergic nerves, VIPergic nerves may participate in the autonomic nervous control of thyroid function.
TL;DR: A polynomial approximation scheme is presented for the Subset-Sum Problem and it is proved that its worst-case performance dominates that of Johnson's well-known scheme.
Abstract: Given a set ofn positive integers and another positive integerW, the Subset-Sum Problem is to find that subset whose sum is closest to, without exceeding,W. We present a polynomial approximation scheme for this problem and prove that its worst-case performance dominates that of Johnson's well-known scheme.
TL;DR: In this paper, a new measurement of the positive muon lifetime by a pulsed-beam technique was presented, τ μ + = 2197.078 ± 0.073 ns.