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1.
Emma Bricchi Marco Fornaciari Claudia Giannoni Francesca Greco Daniela Fascini Giuseppe Frenguelli Gianfranco Mincigrucci Bruno Romano 《Aerobiologia》1992,8(3):401-406
Summary Gramineae pollination from a pollen monitoring station located in the eastern suburb of Perugia and meteorological correlations are reported. The data refers to the year 1989. Grass pollen peak pollination was from May to July; in this period the influence of relative humidity and of temperature on pollen concentration was very high. Phenological observations, to identify the time of maximum stamen extension in the most common genera in the area, are also reported. During the period of investigation the counts of pollen grains over four-hour periods showed a regular diurnal rhythm with peaks of concentration in the four-hour period 16.00–20.00. Aerosporological data and meteorological data related to four-hour periods were correlated following different criteria. 相似文献
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Effects of choline deficiency on rat hepatocytes 总被引:6,自引:0,他引:6
B Lombardi 《Federation proceedings》1971,30(1):139-142
4.
Pampatheres are extinct, large‐bodied cingulates, which share morphological characters with both armadillos and glyptodonts but are considered to be more closely related to the latter. The osteoderm histology of six pampathere taxa was examined and compared to the histology of other cingulate osteoderms. This study investigates the development and functional adaptation of pampathere osteoderms as well as the phylogenetic relationships of the Pampatheriidae within the Cingulata. We found that pampathere osteoderms share a uniform histological organization based on a basic diploe‐like structure. After initial stages of intramembranous growth, metaplastic ossification, that is, the direct incorporation and mineralization of pre‐existing protein fibers, plays an important role in osteoderm development and provides information on various kinds of soft tissue otherwise not preserved. The latest stages of osteoderm growth are dominated by periosteal bone formation especially in the superficial cortex. Movable band osteoderms show regular arrangements of incorporated fibers that may increase the resistance of particularly weak areas against strain. The histological composition of pampathere osteoderms is plesiomorphic in its basic structure but shows a number of derived features. A unique array of Sharpey's fibers that are incorporated into the bone matrix at sutured osteoderm margins is interpreted as a synapomorphy of pampatheres. The arrangement of dermal fibers in the deep and superficial cortexes supports the close relationship between pampatheres and glyptodonts. J. Morphol., 2012. © 2011 Wiley Periodicals, Inc. 相似文献
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V Lombardi F Capuano A Coci T R Broun R Graham 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1990,(6):51-60
Physiological and biochemical processes which take place in the nervous system at stroke and neurotrauma are reviewed, and the experience of using low doses of steroid derivatives with piridamole in the treatment of central nervous system (CNS) disorders is summarized. ATPases (including Na,K-ATPase) are reported to play an important role in CNS functioning, the correlation between Na,K-ATPase activity and the extent of CNS injury is revealed. The use of NMR-spectroscopy method for investigation of brain and spinal cord condition in vivo is suggested. 相似文献
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Conclusive diagnosis of hepatic and pancreatic malignancies by fine needle aspiration 总被引:1,自引:0,他引:1
A study of the diagnosis of hepatic and pancreatic malignancies by fine needle aspiration (FNA) was made, based on 221 aspirates obtained from 209 patients with histologic or clinical confirmation: 159 with hepatic and 50 with pancreatic lesions. The values of sensitivity, specificity and predictivity for positive FNA results were, respectively, 0.84, 0.96 and 1.0 for the liver and 0.76, 1.0 and 1.0 for the pancreas. The composition of the case material showed an incidence of malignant tumors of the liver and pancreas of 84% and 60%, respectively (among which the primary malignancies were 39% and 48%), while nonneoplastic lesions had incidences of 14% and 40%. However, conclusive FNA diagnoses of the histologic type of the primary and the site of origin of metastatic tumors were made in 60% of the hepatic lesions but in only 9% of the pancreatic lesions. Primary hepatocellular carcinoma was diagnosed by FNA of the liver in 95% of the cases; FNA specifically diagnosed 42% of intrahepatic bile duct carcinomas and 40% of hepatic metastases. These findings correlate with the unique cytologic features of primary hepatocellular carcinoma of intrahepatic rather nonspecific morphology of carcinoma of intrahepatic and extrahepatic origin, as well as of pancreatic ductal origin. 相似文献
9.
Daniela Zemlová 《Biologia Plantarum》1986,28(5):396-398
10.
Secondary components of visual evoked potentials (slow negative wave-SNW, and photically-evoked sensory afterdischarge-SAD) are known to be precursors of experimentally activated wave-spike discharges, similar to wave-spikes of petit mal epilepsy. Both SNW and SAD may be potently suppressed wither by amphetamine or GABAergic compounds such as diazepam and sodium valproate. A hypothesis was tested in the present study, that amphetamine-induced suppression of wave-spike discharges may require GABA-benzodiazepine activity for its expression.Electrocortical activity was recorded and averaged in unrestrained albino rats with chronically implanted epicortical electrodes. SNW and SAD obtained in habituated rats in the predrug state were potently suppressed by amphetamine (1 mg/kg, i.p.). Fifteen minutes after amphetamine injection, a challenging drug (metrazol, picrotoxin, convulsant benzodiazepine, Ro 5-3663, or imidazodiazepine, Ro 15-1788) was administered intraperitoneally. Subconvulsive doses of metrazol (10 mg/kg) reversed amphetamine suppression; imidazodiazepine (20 mg/kg) and picrotoxin (1.5 mg/kg) reliably opposed the SNW suppression; convulsant benzodiazepine, Ro 5-3663 (2 mg/kg), showed modest and nonsignificant effect in the same direction. It is proposed that the antiepileptic potency of amphetamine may be associated with its ability, apparently via modulatory effect of norepinephrine, to facilitate the activation of benzodiazepine-GABA receptors. 相似文献