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Nitric oxide (NO) is a powerful vasodilator, involved in both physiological functions and pathophysiological alterations of various regulatory processes, for example, the maintenance of vascular tone and inflammation. The recently demonstrated impact of exogenous NO on the central nervous system extends its role under normal and pathological conditions. At times neuroprotective, at times neurotoxic, NO is capable of different effects depending upon the extent of cerebral damage, the cellular redox state, and the spatiotemporal coordinates and concentration at which it is synthesized. This review provides new insights into the short‐ and long‐term effects of endogenous and exogenous NO in brain injury. ANN NEUROL 2013;73:442–448  相似文献   
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Background: To help immigrant and refugee adolescents experiencing a severe academic delay cope with adversity, a school‐based intervention combining drama workshops and language awareness activities was piloted in two classrooms. Method: A qualitative analysis of participant observations was performed and the Strength and Difficulty Questionnaire and its Impairment Supplement was administered before and after the intervention. The observations were carried out in two Montreal high schools serving an underprivileged neighbourhood of immigrants, involving two classrooms of underschooled adolescents (n = 27) and two classes of similarly underschooled adolescents chosen among other teachers interested in the intervention, who accepted to participate as a comparison group (n = 28). Results: The adolescents shared their experiences of adversity and felt empowered by the workshops. Self‐reported impairment decreased in the intervention groups. Conclusion: The protective effect of creative language activities for immigrant and refugee youth should be further investigated.  相似文献   
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PURPOSE OF REVIEW: Hospitalization and mortality rates associated with heart failure are persistently high. This is due partly to aging of the population but mostly to delayed progress in the pharmacological treatment of decompensated heart failure. We will review the current recommendations and most recent advancement in the pharmacological treatment of acute decompensated heart failure while providing a systematic approach to the management of this prevalent condition. RECENT FINDINGS: Loop diuretics, nitrates and inotropes such as dobutamine and milrinone are the current mainstay of acute heart failure management although their associated morbidity and possible mortality have raised serious concerns. Recent vasoactive agents such as Nesiritide, Tolvaptan and more recently the inotropic agent Levosimedan could offer improved hemodynamics and congestive relief to patients in acute pulmonary edema. SUMMARY: Despite the promising results of these agents, further clinical trials are required prior to their international approval as first-line therapy. Although we can be optimistic that these vasoactive drugs might have favorable clinical outcomes and improve the intricate management of decompensated heart failure, their associated mortality benefit remains unclear and controversial.  相似文献   
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There are conflicting data regarding the ability of the liver to regenerate after partial hepatectomy in animals and humans with cirrhosis. The purpose of this study was to document liver regeneration after partial hepatectomy in a carbon tetrachloride rat model of cirrhosis and to determine whether exogenous putrescine, a polyamine that has been reported to stimulate liver regeneration in animal models of acute liver failure, enhances regenerative activity in cirrhosis. Liver fibrosis and cirrhosis were produced by weekly intragastric gavage with carbon tetrachloride in 130 adult male rats. Vehicle-gavaged rats (n = 12) served as healthy controls. At surgery and at 4 and 8 hr after 70% hepatectomy, rats received normal saline solution or 1 or 10 mg/kg putrescine by intraperitoneal injection. Another group (n = 32) of carbon tetrachloride-treated rats was given putrescine (100 mg/kg) or normal saline solution twice daily for 10 days before partial hepatectomy and at 0, 4 and 8 hr after partial hepatectomy. Liver regeneration was documented 24 and 48 hr after partial hepatectomy on the basis of restitution of liver mass, ornithine decarboxylase activity and [3H]thymidine incorporation into liver DNA. Automated image analysis of the resected liver specimens separated carbon tetrachloride-treated rats into two subgroups: those with bridging fibrosis (fibrotic group) and those with micronodular cirrhosis (cirrhotic group). Restitution of liver mass and ornithine decarboxylase activity at 24 and 48 hr after partial hepatectomy were similar to carbon tetrachloride-treated rats (both fibrotic and cirrhotic) and vehicle-treated healthy controls.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Glanzmann thrombasthenia (GT) is an inherited disorder where an absence of platelet aggregation is associated with quantitative or qualitative abnormalities of the alphaIIbbeta3 integrin. In rare patients, amino acid substitutions have provided information on the functional significance of specific domains within alphaIIb or beta3. We now report an elderly male GT patient (R.M.) from the south west of France whose platelets possess a small residual expression of alphaIIbbeta3. Furthermore, the integrin failed to undergo the necessary conformational changes following platelet activation to permit the binding of fibrinogen or activation-dependent monoclonal antibodies despite the presence of an RGD-binding site. Screening of the alphaIIb and beta3 genes by PCR-SSCP revealed a heterozygous mutation at position 685 in exon 5 of the beta3 gene leading to a 196Leu to Pro substitution. 196Leu is a highly conserved amino acid of beta3. The other beta3 allele appeared to be silent. This mutation, inherited from his mother and present in other family members with intermediate levels of alphaIIbbeta3, was close to the MIDAS-like domain of beta3, a fact that appears to explain its effect on alphaIIbbeta3 activation and fibrinogen binding.  相似文献   
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Socie  G; Gluckman  E; Raynal  B; Petit  T; Landman  J; Devergie  A; Brison  O 《Blood》1993,82(7):2249-2256
Since 1976, patients grafted at the Hopital Saint-Louis for Fanconi anemia (FA) without evidence of leukemic transformation have been given a uniform conditioning regimen that consisted of low-dose cyclophosphamide (Cy) and thoracoabdominal irradiation (TAI). The use of low-dose Cy raised the question of whether it is sufficient for the establishment of a complete hematopoietic chimerism in all patients. We therefore initiated a study of chimerism early during hematopoietic reconstitution after bone marrow transplantation (BMT) and thereafter in transplanted FA patients. Minisatellite probes were used after DNA amplification by the polymerase chain reaction (PCR). From July 1989 to October 1992, 24 consecutive patients underwent BMT for FA, 19 of whom were assessable for chimerism. Our results using this sensitive technique showed that, among these 19 patients, all but one successfully engrafted. Engraftment was complete early after BMT in 12. The persistence of a small proportion of recipient's cells was detected in six. This partial hematopoietic chimerism was demonstrated to be only transient in at least five of the six patients. The one patient who failed to engraft showed a recipient-type profile for circulating cells early posttransplantation, indicating autologous bone marrow recovery. A second graft in this patient was also rejected. For both transplantations, the patient was grafted from a matched, unrelated donor. Therefore, 17 of 17 patients successfully grafted and with complete follow up data presented complete hematopoietic chimerism, within the sensitivity limit of the method used. In conclusion, lowering the Cy dose in the conditioning regimen of patients with FA could still allow complete engraftment to occur, at least in patients with an identical sibling donor.  相似文献   
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