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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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Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details.  相似文献   
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Background  

Heart chambers rupture in blunt trauma is uncommon and is associated with a high mortality. The determinant factors, and the incidence of isolated heart chambers rupture remains undetermined. Isolated rupture of the right atrium appendage (RAA) is very rare, with 8 cases reported in the reviewed literature. The thin wall of the RAA has been presumed to render this chamber more prone to rupture in blunt trauma.  相似文献   
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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   
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Purpose  To present a case of brainstem anaesthesia as a complication of peribulbar anaesthesia. Clinical features  A 75-yr-old woman received peribulbar anaesthesia for cataract surgery. A few seconds after the block was performed, she had a respiratory arrest, became unconscious, and developed hypertension and tachycardia followed by hypotension and bradycardia. Ventilatory and haemodynamic support were performed before the patient regained adequate spontaneous breathing and normal heart rate and blood pressure. Conclusion  Peribulbar anaesthesia generally cames a low risk of serious complications. However, respiratory arrest and brainstem anaesthesia may occur as complications of peribulbar blocks.
Résumé Objectif  Présenter un cas d’anesthésie du tronc cérébral compliquant une anesthésie péribulbaire. éléments cliniques  Un bloc péribulbaire était réalisé chez une femine de 75 ans pour l’extraction d’une cataracte. Quelques secondes après l’injection, la patiente cessait de respirer et perdait conscience. Elle devenait hypertendue et tachycarde puts hypotendue et bradycarde. La ventilation et la circulation devaient être supportées jusqu’au retour spontané à la normale. Conclusion  En général, l’anesthésie péribulbare comporte un faible risque de complications sérieuses. Un arrêt respiratoire par anesthésie du tronc cérébral est toujours possible.
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The relationship between farming and cancer risk was investigated in an integrated series of case-control studies conducted from 1985 to 1991 in the Friuli Venezia Giulia region, north-east Italy. Patients with cancer of the oral cavity and pharynx, larynx, oesophagus, colon and rectum, pancreas, breast, thyroid gland, kidney and urinary tract, bladder, prostate, soft-tissue sarcomas, Hodgkin's diseases, non-Hodgkin's lymphomas and multiple myelomas, and controls admitted to hospital for acute, non-neoplastic conditions, were interviewed. For males, a significantly elevated relative risk was seen for oral cavity and pharynx. Farming, however, was associated with a significant protection against cancer of the colon and rectum and bladder. In females, only one significant association emerged, for multiple myeloma. A few significant interactions between cancer risk and year of birth (i.e., before 1930 or 1930 and after) were observed. The risk of cancer of the larynx was significantly elevated in younger male farmers but not in older ones. Our multi-site case-control study confirms that farmers have, for some cancer sites, a distinctive pattern. Excesses of cancer of the oral cavity and pharynx in farmers are characteristic of the present study area and, possibly, of similar European rural populations who have in common high levels of alcohol consumption and, at least in the past, unbalanced diets.  相似文献   
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