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Background and PurposeSome de- and re-polarization patterns can reflect an increased risk of ventricular tachyarrhythmias. We studied whether some electrocardiographic (ECG) patterns are able to predict the development of ventricular fibrillation (VF) during acute myocardial infarction (MI).MethodsWe compared the patterns of ST-T segment of 78 patients who developed VF during acute MI (patient with VF) vs 170 comparable patients with acute MI but with no VF complications.ResultsOf the VF group, 47 developed out-of-hospital VF and 31 developed VF after their admission to the hospital. A steep downsloping ST segment toward a negative T wave with or without a short, flat, or rising portion at the initial portion was observed in 69.2% of the 78 patients: 61.3% in patients with pre-VF and 74.5% in patients with post-VF, vs 9.4% of patients who did not develop VF (P < .0001). In 90.6% of the latter, a typical upward-concave or convex “ischemic” pattern of the ST segment was observed. Thus, the characteristic ST-T patterns were highly associated with VF with a specificity greater than 90%.ConclusionsA steep downsloping ST segment may characterize the ECGs of patients who develop VF during acute MI.  相似文献   
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ObjectivesSulfated glycoconjugates (S-GCs) are essential components of dentinogenesis and osteogenesis, and are involved in the regulation of the mineralization process. The scales of Polypterus senegalus, which are homologous to teeth and phylogenetically derived from ancestral dermal skeleton, comprise true enamel, dentine, and bone. As part of the phylogenic evolutional studies on mesenchyme-derived hard tissues, we investigated the ultrastructural distribution patterns and histochemical properties of S-GCs in the dentine and bone of scales.MethodsFor detection of S-GCs, a high iron diamine–thiocarbohydrazide–silver proteinate (HID–TCH–SP) staining technique was used.ResultsS-GCs were observed in unmineralized predentine and osteoid, mineralized dentine, osteocyte pericellular matrix, but not in mineralized bone and isopedine. Most S-GCs in the dentine and osteoid were susceptible to testicular hyaluronidase, indicating that they are chondroitin sulfates.ConclusionDistinct differences in the S-GC distribution pattern between the dentine and bone were observed. The S-GC distribution pattern associated with the dentinogenesis of scales is very similar to that of mammalian mantle dentine.  相似文献   
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We report a case of rheumatoid vasculitis (RV) that responded well to abatacept, a cytotoxic T lymphocyte-associated antigen 4 (CTLA4)-immunoglobulin fusion protein. A 38-year-old woman developed RV despite treatment with methotrexate and tumor necrosis factor (TNF) inhibitors. The effects of steroid therapy, immunoabsorption plasmapheresis, and interleukin-6 inhibitor were insufficient, however, administration of abatacept rapidly improved her clinical symptoms with almost normalization of the immunological findings. This is the first published case report of the successful treatment of RV with abatacept.  相似文献   
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Background

Preoperative traction for hip fractures is of no benefit in semi-urgent surgery. However, its efficacy has not been assessed in cases in which emergency surgery was not possible. We evaluated the efficacy of preoperative skin traction for hip fractures in a level II trauma center in Japan where many patients undergo delayed surgery.

Methods

We undertook a randomized controlled trial. Eighty-one patients were randomized to be treated with skin traction (41 patients), or bed rest (40 patients). Preoperative pain was assessed by use of a visual analogue scale and the number of analgesics required. Fracture reduction was measured on the basis of leg-length and neck–shaft angle discrepancies on the radiograph on admission, a day before surgery, and after surgery.

Results

The mean time from admission to surgery was 7.5 days. Pain decreased markedly on the day after admission in both the traction and no-traction groups. No significant difference was found during the preoperative waiting period between the groups in either pain score or number of analgesics taken. No significant difference was found in radiographic data either before or after surgery, and satisfactory reduction was achieved after surgery irrespective of the use of skin traction.

Conclusions

In our single-institution prospective randomized controlled trial, preoperative skin traction for patients with hip fracture had no effect on pain relief before surgery or reduction of fracture displacement during surgery, irrespective of preoperative waiting time.  相似文献   
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