A Comparative Study of Septoplasty With or Without Nasal Packing

This study was conducted to compare the outcome of septoplasty with or without Nasal packing. The study subjects were randomly allocated into two groups. There was significant reduction in frequency of post operative pain, headache, discomfort and duration of hospital stay in patients who have undergone septoplasty without nasal packing. However there was no difference in post operative bleeding and septal perforation between two groups. Therefore after Septoplasty without nasal packing is preferred alternative to with nasal packing

The role of COX-2 in rectal cancer treated with preoperative radiotherapy

Radiotherapy is one of the principal modalities of rectal cancer treatment, and the ability to predict radio resistance could potentially improve survival through a targeted treatment approach. Cyclooxygenase-2 (COX-2) may protect against damage by irradiation that would justify the use of COX-2 inhibitors. The purpose of this study was to investigate the potential role of COX-2 in tumor response and outcome of patients with rectal cancer treated preoperatively with radiotherapy. Using immunohistochemistry, we examined COX-2 expression in 88 surgical specimens of rectal cancer treated preoperatively and in 26 pretherapeutic biopsies. We tested whether COX-2 expression was correlated with clinico-pathologic parameters and with survival and local recurrence. COX-2 was expressed in 50% of the pretherapeutic tumor biopsies and in 88.6% of post-irradiated surgical samples. COX-2 expression was correlated only with enhanced tumor inflammation (p=0.03) and with tumor volume exceeding 30 cc (p=0.05). COX-2 was not significantly correlated with patient survival, but none of the patients with COX-2 negative tumors did recur locally, whereas 80% of patients with local recurrences have COX-2 positive tumors. We conclude that COX-2 expression is overexpressed in the majority of rectal cancers treated with radiotherapy and likely plays a role in local relapse

Catalytic CO2 Hydrogenation on Nickel: Novel Insight by Chemical Transient Kinetics

Carbon dioxide hydrogenation on support-free nickel model catalysts was investigated by means of a time-resolved quantitative analysis of chemical transients triggered by abrupt changes in the reactant partial pressures. It was found that carbon dioxide adsorption is strongly affected by the presence of hydrogen and by coadsorption effects and thus influences the reaction rate in the buildup and back transients. The observed transients suggest that two reaction mechanisms operate in parallel, which is consistent with previous results obtained using a Ni single-crystal termination. The initial reaction rate involves fast direct hydrogenation of CO2, whereas the rate under steady-state conditions is lower due to a change in the mechanism involving an oxygen-containing intermediate. © 2010 American Chemical Society.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Direct methane-to-methanol conversion: Insight from first-principles calculations

A simple direct mechanism for methane-to-methanol conversion has been investigated by first principles on a series of oxygen-precovered transition-metal surfaces. Energy barriers and reaction paths have been determined for three competing elementary processes by the nudged elastic band algorithm. Indicators of reactivity toward each elementary step have been identified, providing significant insight into a rational search for a suitable catalyst. The effect of chemical environment, local geometry, strain, and coadsorption have been addressed, and general guidelines have been identified. On the basis of this analysis, we suggest that upon suitable conditions O-dosed Ag surfaces could display considerable reactivity toward direct methane-to-methanol conversion