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Introduction: Pacemakers and implantable cardioverter-defibrillators (ICDs) are vulnerable to inappropriate sensing of electromagnetic interference (EMI), such as from nerve conduction studies. We conducted a prospective study to assess the safety of repetitive nerve stimulation (RNS). Methods: Fourteen patients undergoing insertion of 10 ICDs and 4 pacemakers under general anesthesia received RNS of the median, axillary, and spinal accessory nerves at 2 HZ and 50 HZ . We recorded detection of EMI and whether or not this resulted in an arrhythmia diagnosis or change in pacing output. Results: EMI was visible in 2 ICDs, without spurious tachyarrhythmia detection. EMI was observed in 3 of the 4 pacemakers, which led to pacing inhibition and a pause in 2, both of which were programmed to a unipolar sensing configuration. Conclusions: RNS is safe in patients with ICDs. In pacemaker patients, RNS appears safe during bipolar sensing, but caution is recommended in pacemaker patients with unipolar sensing. Muscle Nerve 47: 840–844, 2013  相似文献   
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Background

The Essential Medicines Working Group of the International Society of Pediatric Oncology (SIOP) has proposed a list of antineoplastic drugs that should be available in low and middle income countries.

Procedure

Data were extracted on the listing of 18 essential and 8 ancillary antineoplastic medicines in the national essential medicines lists (NEMLs) or national reimbursable medicines lists (NRMLs) of 135 countries with gross national income (GNI) per capita of less than US $25,000. Correlations between numbers of medicines listed and GNI per capita, annual government health expenditure (AGHE) per capita, and the number of physicians per million people were examined.

Results

Listing of the 18 essential antineoplastic drugs ranged from 27% (thioguanine) to 95% (methotrexate). The median number of medicines listed was 7 (0–18) in low income countries (n = 26) and 14 in lower‐middle (n = 42), upper‐middle (n = 44), and high income countries (n = 20). For the ancillary eight medicines, the median was one (0–8) across the 135 countries. Correlations with GNI per capita (r = 0.17, P = 0.0266) and physician density (r = 0.25, P = 0.0017) were statistically significant; not so for AGHE per capita (r = 0.00, P = 0.5000).

Conclusions

There was large variability within income groups in numbers of antineoplastic agents identified as essential in NEMLs and NRMLs. While not a direct measure of availability, listing is an important step, guiding procurement for the public sector. These results focus attention on deficits in NEMLs and NMRLs as a step to improving access to effective antineoplastic medicines for cancers in children in low and middle income countries. Pediatr Blood Cancer © 2015 Wiley Periodicals, Inc.  相似文献   
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There has been mounting speculation that calcium antagonists may be useful in reducing or preventing brain damage after cardiopulmonary resuscitation. To test the clinical usefulness of these agents in averting such damage, high-dose verapamil was administered to baboons and pigs after partial cerebral ischemia for varying periods of time. In Group A baboons and pigs, the major aortic branches supplying the carotid and vertebral circulations were clamped for periods ranging from 15 to 150 minutes, and neurological recovery was observed. In Group B, verapamil hydrochloride 0.7 mg/kg was given by intravenous infusion after similar periods of arterial occlusion. The administration of verapamil did not lead to any clinically improved neurological outcome. The use of verapamil after prolonged periods of partial cerebral ischemia did not improve neurological recovery in baboons and pigs.  相似文献   
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