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991.
Aims Despite proven benefits of antiretroviral therapy (ART), many human immunodeficiency virus (HIV)‐infected injection drug users (IDU) do not access treatment even in settings with free health care. We examined whether methadone maintenance therapy (MMT) increased initiation and adherence to ART among an IDU population with free health care. Design We examined prospectively a cohort of opioid‐using antiretroviral‐naive HIV‐infected IDU and investigated factors associated with initiation of antiretroviral therapy as well as subsequent adherence. Factors associated independently with time to first initiation of antiretroviral therapy were modelled using Cox proportional hazards regression. Findings Between May 1996 and April 2008, 231 antiretroviral‐naive HIV‐infected opioid‐using IDU were enrolled, among whom 152 (65.8%) initiated ART, for an incidence density of 30.5 [95% confidence interval (CI): 25.9–35.6] per 100 person‐years. After adjustment for time‐updated clinical characteristics and other potential confounders, use of MMT was associated independently with more rapid uptake of antiretroviral therapy [relative hazard = 1.62 (95% CI: 1.15–2.28); P = 0.006]. Those prescribed methadone also had higher rates of ART adherence after first antiretroviral initiation [odds ratio = 1.49 (95% CI: 1.07–2.08); P = 0.019]. Conclusion These results demonstrate that MMT contributes to more rapid initiation and subsequent adherence to ART among opioid‐using HIV‐infected IDU. Addressing international barriers to the use and availability of methadone may increase dramatically uptake of HIV treatment among this population.  相似文献   
992.

Background  

Although the incidence of atrial fibrillation (AF) progressively increases with age, the vast majority of AF ablation is done in middle-aged patients. We evaluated the feasibility and safety of catheter ablation in patients older than 65 years of age with paroxysmal and persistent AF.  相似文献   
993.
Acetyl-CoA carboxylase (ACC) is a key enzyme of fatty acid metabolism with multiple isozymes often expressed in different eukaryotic cellular compartments. ACC-made malonyl-CoA serves as a precursor for fatty acids; it also regulates fatty acid oxidation and feeding behavior in animals. ACC provides an important target for new drugs to treat human diseases. We have developed an inexpensive nonradioactive high-throughput screening system to identify new ACC inhibitors. The screen uses yeast gene-replacement strains depending for growth on cloned human ACC1 and ACC2. In “proof of concept” experiments, growth of such strains was inhibited by compounds known to target human ACCs. The screen is sensitive and robust. Medium-size chemical libraries yielded new specific inhibitors of human ACC2. The target of the best of these inhibitors was confirmed with in vitro enzymatic assays. This compound is a new drug chemotype inhibiting human ACC2 with 2.8 μM IC50 and having no effect on human ACC1 at 100 μM.  相似文献   
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995.

Background  

Stress-only imaging saves time and radiation exposure, but apprehension remains about the reliability, diagnostic, and prognostic accuracy of a normal stress-only study. The objective of this study was to determine the prognosis of stress-only SPECT MPI in routine clinical practice.  相似文献   
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Therapeutic red blood cell (RBC) transfusion is widely utilized in the management of anaemia. Critically ill intensive care unit (ICU) patients in particular, as well as medical and haematology–oncology patients, are among the largest groups of users of RBC products. While anaemia is common in these patients, its treatment and management, including appropriate thresholds for RBC transfusion, remain controversial. We review here the function of RBCs in oxygen transport and physiology, with a view to their role in supporting and maintaining systemic tissue oxygenation. Adaptive and physiological compensatory mechanisms in the setting of anaemia are discussed, along with the limits of compensation. Finally, data from clinical studies will be examined in search of evidence for, or against, a clinically relevant transfusion trigger.  相似文献   
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