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Vigilio Ballabeni Massimiliano Tognolini Simona Bertoni Renato Bruni Alessandra Guerrini Gabriela Moreno Rueda Elisabetta Barocelli 《Pharmacological research》2007,55(1):23-30
Ocotea quixos essential oil was shown to possess significant inhibitory activity of platelet aggregation and clot retraction in rodent plasma. This study is aimed at fully characterizing the antiplatelet activity of the whole essential oil and its main components trans-cinnamaldehyde and methyl cinnamate also in human plasma, at investigating the mechanism underlying such activity and at evaluating the potential antithrombotic activity of subacute treatment of mice with Ocotea essential oil. In vitro Ocotea essential oil and trans-cinnamaldehyde inhibited arachidonic acid-, U46619-, ADP-, phorbol12-myristate13-alcetate-, collagen-induced platelet aggregation and thrombin-induced clot retraction in human and rodent plasma; Ocotea oil and trans-cinnamaldehyde competitively antagonized contractions induced by thromboxane A2 receptor agonist U46619 in rat isolated aortic ring (K(B) = 18 and 3.2 microg ml(-1), respectively). In vivo Ocotea oil, orally administered in a subacute treatment (30-100 mg kg(-1) day(-1) for 5 days) to mice, prevented acute thrombosis induced by collagen-epinephrine intravenous injection. This antithrombotic activity was not accompanied by pro-haemorragic side effect, as detected by the inactivity in bleeding test, thus showing a favourable safety profile compared to the conventional antiplatelet agent, acetylsalicylic acid. Present findings indicate that Ocotea essential oil possesses potent and safe antithrombotic activity attributable to its antiplatelet and vasorelaxant effects. The main constituent trans-cinnamaldehyde seems to be the primary responsible for this activity through a putative mechanism involving the inhibition of thromboxane A2 receptors. 相似文献
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Hilda A. Perez Carmen Bracho Mirtha Romano Mercedes De la Rosa 《Parasitology research》1997,83(3):246-251
A monoclonal antibody raised by immunization of BALB/c mice with erythrocytic stages of Plasmodium vivax was shown to react with asexual erythrocytic stages of P. chabaudi. The cross-reactivity molecules are antigens of 200 and 148 kDa in P. vivax and of 190 and 70 kDa in P. chabaudi. Immunofluorescence studies of the erythrocytic stages of P. vivax and P. chabaudi indicated that expression of these antigens increased as the parasites' developed from the ring stage to the schizont stage.
In the mature trophozoites of P. chabaudi, immunoelectron microscopy revealed clusters of antigen distributed in the cytoplasm of the parasitized erythrocyte. In the
schizont, packets of antigen were found associated with the parasitophorous vacuole and the cytoplasm of the infected host
cell.
Received: 19 March 1996 / Accepted: 28 August 1996 相似文献
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H S Matloub C D Prevel J R Sanger N J Yousif C A Devine J Romano 《Annals of plastic surgery》1992,29(6):559-563
Several articles have been published that bring attention to the destructive potential of tire explosions. Although the severity of tire explosion injuries to the head and neck region is well established, only one previous article has reported injuries to the upper extremity. Fourteen patients with upper extremity tire explosion injuries have been treated by us from 1980 to 1988. Each injury was caused by single-piece wheel assemblies, as opposed to multipiece wheel assemblies, which have traditionally been associated with the injury. Three representative patient reports are discussed. Prevention of this injury can be achieved by increased public awareness, formal industrial safety training, tire servicing with dedicated equipment including restraining devices or barriers, complete evaluation of wheel/tire serviceability before tire mounting, separation of servicing of single and multipiece wheels, and complete tire deflation before servicing. 相似文献
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Symptom profile of DSM-IV major and minor depressive disorders in first-ever stroke patients. 总被引:1,自引:0,他引:1
Gianfranco Spalletta Alessandra Ripa Carlo Caltagirone 《The American journal of geriatric psychiatry》2005,13(2):108-115
OBJECTIVE: Depressive disorders are very common in stroke patients. However, vegetative and cognitive symptoms primarily derived from brain damage could hypothetically be indistinguishable from those directly derived from neuropsychiatric disorders, and this could invalidate the diagnostic assessment. Thus, authors aimed to detect the frequency of clinically-rated DSM-IV depressive symptoms and the diagnostic validity of depressive disorders in stroke patients suffering from major depressive disorder (MDD), minor depressive disorder (MIND), and those free of any neuropsychiatric disorders (NODEP). METHODS: First-ever stroke patients (N=200) were approached within 3 months of the acute stroke and were interviewed with the SCID-P and administered the Hamilton Rating Scale for Depression (Ham-D), the Beck Depression Inventory (BDI), the Barthel Index, and the Mini-Mental State Exam. RESULTS: Fifty patients (25%) had MDD, 62 (31%) had MIND, and 88 (44%) had NODEP. Global cognitive level, functional impairment, total scores, and psychic and somatic subscores of the Ham-D and the BDI were different among the three groups. The only symptom that did not differ among patients with MDD, MIND, and NODEP was Feelings of Guilt; all the other eight DSM-IV symptoms were significantly different. In particular, the frequency of Depressed Mood, Diminished Interest or Pleasure, Fatigue or Loss of Energy, Insomnia, and Psychomotor Agitation/Retardation was higher in MIND patients than in NODEP patients. CONCLUSIONS: During the diagnostic procedure for depressive disorders in stroke patients, clinicians should consider equally important vegetative, cognitive, and psychological depressive symptoms, despite their nature. 相似文献
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Giangennaro Coppola Francesca Felicia Operto Gianfranca Auricchio Alessandra D'Amico Delia Fortunato Antonio Pascotto 《Epileptic Disord》2007,9(2):145-148
A child had the characteristic clinical and EEG pattern of migrating partial seizures in infancy with left temporal lobe atrophy, hippocampal sclerosis and cortical-subcortical blurring.Seizures were drug-resistant, with recurring episodes of status epilepticus. The child developed microcephaly with arrest of psychomotor development. Focal brain lesions, in the context of migrating partial seizures, have not been previously reported.[Published with video sequences]. 相似文献
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Angela Alama Federica Barbieri Renato Spaziante Cristina Bruzzo Patrizia Dadati Alessandra Dorcaratto Jean Louis Ravetti 《Journal of clinical neuroscience》2007,14(4):355-358
Forty-four evaluable patients with intracranial meningiomas were assessed for the expression of the cell-cycle regulator cyclin D1 and of proteins involved in proliferation and apoptosis such as PCNA, MIB-1, p53 and bcl-2. Analyses were carried out by western blot and immunohistochemistry after immediate processing of fresh tumor specimens. By western blot, expression of cyclin D1 significantly correlated with p53 (p=0.02) and with proliferative activity, as assessed by PCNA expression (p=0.0009). By immunohistochemistry, a significant relationship between cyclin D1 and the proliferation marker MIB-1 was confirmed (p=0.05), whereas significance with bcl-2 expression was not found (p=0.01). Moreover, although the association with tumor grade appeared of borderline statistical significance (p=0.07), all the grade II/III meningiomas showed increased expression of cyclin D1 and high proliferative activity. In conclusion, data from this preliminary study seem to suggest a potential value of the combined expression of cyclin D1 and proliferation indicators in defining subgroups of meningiomas with a more aggressive biological behavior. 相似文献