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41.
In this study, we studied the role of adenosine on airway responsiveness and airway inflammation using an allergic mouse model. Mice were sensitized by two i.p. injections of ragweed and three consecutive ragweed aerosol challenges. It was found that inhalation of adenosine causes a dose-related bronchoconstriction in this model. Ragweed sensitized and challenged mice showed increased sensitivity to airway challenge to adenosine compared to control animals. Theophylline, a non-selective adenosine receptor antagonist, blocked adenosine-induced bronchoconstriction, but was unable to inhibit bronchoconstrictor response to methacholine. Mice systemically sensitized and airway challenged with allergen showed a marked airway inflammation manifesting increases in eosinophils, lymphocytes and neutrophils, and decrease in macrophages. Twenty-four hours after airway challenge with allergen, aerosolization of adenosine further potentiated the allergen-induced airway inflammation. Cells in bronchoalveolar lavage fluid after adenosine aerosolization increased by 3.07-fold as compared to control mice, and by 1.8-fold compared to ragweed sensitized and challenged mice. The increases in eosinophils, lymphocytes, and neutrophils caused by allergen were potentiated after adenosine challenge. Unexpectedly, macrophages significantly decreased after adenosine challenge. Theophylline attenuated adenosine-enhanced airway inflammation, but could not reverse allergen-induced airway inflammation. These findings suggested that specific adenosine receptors contribute to airway responsiveness and airway inflammation associated with this model of allergic asthma.  相似文献   
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This exploratory study adopts a socio‐ecological approach to examine the context of school bullying. It asks: (1) what are students' accounts of bullying practices?; (2) how are these enabled and constrained by the school‐environment?; (3) how is gender implicated? Qualitative data were collected from girls in two schools in London via focus groups (one in each school; students aged 12‐15) and seven semi‐structured interviews (in one school; students aged 16‐18); and from school policy documents. Our interpretation of girls' accounts, informed by Giddens' structuration theory, suggests that bullying practices were spatially patterned in the schools and often characterised by the regulation of girls' sexuality and sexual‐harassment. Repeated acts of aggression were fluid with regard to the bully and victim role, challenging the dominant view of bullying as characterised by consistent disparities in power between individuals. Schools structured bullying behaviour via policies and practices that ignored these forms of abuse and which focused on and may have been complicit in the making of stable ‘bully’ and ‘victim’ roles, thus indirectly contributing to the reproduction of unhealthy relationships between students. In terms of gender, traditional gendered and sexual discourses appear to structure the identities of the schools and girls in our study.  相似文献   
44.
Management of intracoronary thrombus in patients presenting more than 12 hours after the onset of ST elevation myocardial infarction is challenging. We present such a case which had massive thrombus in left anterior descending artery. It was managed successfully with dual antiplatelet agents and factor Xa inhibitor rivaroxaban administered orally.  相似文献   
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Pre transplant screening work-up of donors for allogeneic blood and marrow transplantation is essential in an effort to minimize risks to the recipient and protect the donor. At Princess Margaret Hospital, every potential donor is screened with a bone marrow aspirate. The case histories of three asymptomatic potential donors who presented within 1 year with normal complete blood counts, history and physical examination are presented. A 65-year-old male patient was diagnosed with smouldering multiple myeloma, a 72-year-old male patient with chronic lymphocytic leukemia and a 42-year-old male patient with myelodysplastic syndrome. Bone marrow examination led to the diagnosis in each one of these cases. Of note is that each of the potential donors was discovered to have the same disease as the transplant recipient. In vitro clonogenic hemopoietic progenitor assays were compared to those of 20 normal volunteers. Inferior growth of hemopoietic progenitor colonies in all three was noted. In conclusion, particularly in older donors and donors with potential for familial malignancies, more screening investigations including bone marrow aspiration may be reasonable to investigate for occult hematological malignancies prior to stem cell donation. Clonogenic assays can contribute to detect hemopoietic abnormalities pre transplant.  相似文献   
47.
Pseudoaneurysm following diagnostic or interventional procedures is a well-known complication. We describe a new method of closing a femoral pseudoaneurysm in a case where ultrasound-guided compression had failed. Instead of packing the sac permanently with coils, thrombus formation was successfully induced by temporary placement of a coil transcutaneously in the psendoaneurysm sac, which resulted in closure of the pseudoaneurysm.  相似文献   
48.
In 1986, the bone marrow transplant centers in Ontario agreed to a strategy for the treatment of patients with NHL. Suitable patients would undergo autotransplant but be referred for allotransplant if they had persistent marrow involvement or an inadequate marrow/stem cell harvest. Data of all patients were recorded in a database. We reviewed this database to compare these transplant modalities with respect to overall survival, rate of relapse and treatment-related mortality. Between January 1986 and August 1997, 429 patients underwent BMT for NHL - 385 autotransplants and 44 allotransplants. Sixty-eight percent of patients received their transplant for aggressive NHL, while the others had indolent lymphoma. Three-year actuarial survival did not differ between allogeneic and autologous BMT: 71% vs 62%, respectively (P = 0.5330 by log-rank testing). Three-year actuarial rate of relapse was lower after allotransplant than autotransplant: 6% vs 41%, respectively (P = 0.0006 by log-rank testing). Treatment-related mortality was higher after allotransplant than autotransplant: 23% vs 6%, respectively (P = 0.001 by chi2 analysis). For further comparison, autotransplant patients were randomly matched 2:1 with the allotransplant patients for age +/- 5 years, disease status at BMT, disease histology, and year of BMT. In the matched comparison, survival did not differ (relative risk of death after allotransplant: 0.711 (95% CI: 0.309-1.637)). Relapse rate was significantly lower in the allotransplant group (relative risk of relapse for allotransplant: 0.190 (95% CI: 0.043-0.834)) and treatment-related mortality was not significantly different (relative risk for allotransplant: 1.425 (95% CI: 0.527-3.851)). In conclusion, a review of a provincial strategy for treatment of NHL, shows that survival is not different after allogeneic or autologous BMT, but the rate of relapse is lower after allotransplant. These data support continuing the current provincial strategy.  相似文献   
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The outbreak of novel coronavirus, SARS-CoV-2, has infected more than 36 million people and caused approximately 1 million deaths around the globe as of 9 October 2020. The escalating outspread of the virus and rapid rise in the number of cases require the instantaneous development of effectual drugs and vaccines. Presently, there are no approved drugs or vaccine available to treat the infection. In such scenario, one of the propitious therapeutic approaches against viral infection is to explore enzyme inhibitors amidst natural compounds, utilizing computational approaches aiming to get products with negligible side effects. In the present study, the inhibitory prospects of ilimaquinone (marine sponge metabolite) were assessed in comparison with hydroxychloroquine, azithromycin, favipiravir, ivermectin and remdesivir at the active binding pockets of nine different vital SARS-CoV-2 target proteins (spike receptor binding domain, RNA-dependent RNA polymerase, Nsp10, Nsp13, Nsp14, Nsp15, Nsp16, main protease, and papain-like-protease), employing an in silico molecular interaction based approach. In addition, molecular dynamics (MD) simulations of the SARS-CoV-2 papain-like protease (PLpro)–ilimaquinone complex were also carried out to calculate various structural parameters including root mean square fluctuation (RMSF), root mean square deviation (RMSD), radius of gyration (Rg) and hydrogen bond interactions. PLpro is a promising drug target, due to its imperative role in viral replication and additional function of stripping ubiquitin and interferon-stimulated gene 15 (ISG15) from host-cell proteins. In light of the possible inhibition of all vital SARS-CoV-2 target proteins, our study has emphasized the importance to study in depth ilimaquinone actions in vivo.

Inhibitory potential of ilimaquinone (marine sponge metabolite) against nine essential SARS-CoV-2 target proteins, employing a molecular interaction and dynamics simulation approach.  相似文献   
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