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101.
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Mohammed A. Qutub MD FRCPC Taylor Dowsley MD PhD Iftikhar Ali MD R. Glenn Wells PhD Li Chen MSc Terrence D. Ruddy MD FRCPC FACC FASNC Benjamin J. W. Chow MD FRCPC FACC FASNC FSCCT 《Journal of nuclear cardiology》2013,20(4):545-552
Background
Though myocardial perfusion imaging (MPI) with single-photon emission computed tomography (SPECT) is an established diagnostic method, equivocal studies are commonly encountered. New software has been introduced that incorporates resolution recovery (RR) and noise regulation into the reconstruction algorithm and has been used to facilitate “half-dose” and “half-time” studies. Its utility with “full-time, full-dose” acquisition has not been well studied.Objective
We sought to understand the potential benefit of incorporating RR software in equivocal SPECT studies.Methods
Patients with full-time, full-dose SPECT MPI were reviewed and those with equivocal results, who subsequently underwent cardiac Rb-82 positron emission tomography (PET) scan were identified. Image reconstruction was performed with iterative reconstruction (IR), attenuation correction (IR + AC), and RR software (IR + AC + RR). Images were anonymized and read blindly by consensus of two experienced readers. All images were qualitatively assessed and semi-quantitatively graded using summed stress and summed rest scores.Results
45 patients were included (28 males, age = 59.6 ± 9.9 years) and the diagnostic accuracy of each of the reconstruction algorithms (IR, IR + AC, IR + AC + RR) was compared to Rb-82 PET. Agreement of clinical diagnosis of each SPECT reconstruction with Rb-PET showed incremental improvement. The agreement with PET for IR + AC + RR (κ = 0.66, CI 0.454-0.875) is significantly better than for IR (κ = 0.22, CI 0.0-0.450, P = .005) and for IR + AC (κ = 0.32, CI 0.077-0.563, P = .03). Also, IR + AC + RR improved the clinical diagnosis in 14 cases and with overall improvement of reclassification proportion of 23.5% compared to IR (P = .01). Using PET as a reference standard, ROC curves were created for IR + AC + RR, IR + AC, and IR which showed incremental value of the area under the curve of IR + AC + RR (AUC: 0.87; CI 0.76-0.98) over IR + AC (AUC: 0.75; CI 0.61-0.89, P = .078), and over IR (AUC 0.68; CI 0.52-0.84, P = .025).Conclusion
The addition of RR may help in the diagnosis of patients with equivocal SPECT MPI without the need for additional testing. Further prospective studies are needed to define the role of this new software. 相似文献103.
目的探讨氯胺酮麻醉前不同时间肌内注射阿托品对小儿呼吸道的影响。方法将2012年1月至2013年6月在廊坊市第四人民医院住院的100例患儿按随机数字表法分为两组:A组(50例)于氯胺酮麻醉前30~60 min肌内注射阿托品(0.02 mg/kg),B组(50例)阿托品(0.02 mg/kg)与氯胺酮同时间肌内注射。两组患儿均于氯胺酮肌内注射2~4 min后入室准备手术,术中观察记录两组患儿呼吸道和肺部的听诊变化及脉搏血氧饱和度(Sp O2)变化。结果 A组Ⅰ级(即呼吸道未受影响)44例,Ⅱ级以上(即呼吸道受到不同程度影响)6例,阳性率为12%(6/50);B组Ⅰ级33例,Ⅱ级以上17例,阳性率为34%(17∕50)。两组患儿呼吸道受影响程度的比较,差异有统计学意义(P<0.01)。结论小儿氯胺酮麻醉前30 min肌内注射阿托品,能有效降低氯胺酮对患儿呼吸道的影响,提高术中患儿的安全系数。 相似文献
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105.
天然乳胶避孕套冒牌贴牌多,监管部门多,监管难度大,本文详细阐述了避孕套监管的现状及加强监管的建议。 相似文献
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Summary A case of graft-vs.-host disease (GVHD) arising solely within an area affected by piebaldism is described. The patient, a 35-year-old woman with a single hypopigmented patch on the right leg present since birth, had received an allogeneic bone marrow transplant (BMT) from an HLA-identical sibling donor, for treatment of a myelodysplastic syndrome (MDS). Beginning on day + 38 post-BMT, the patch developed changes which were histologically consistent with GVHD. Syngeneic mixed epidermal cell-lymphocyte reaction (MECLR) testing of tissue from the patch, and from adjacent normal skin, showed differences which suggest that piebaldism-affected skin is immunologically different from normal skin. These findings may offer new insight into the pathophysiology of this disorder. 相似文献
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肝细胞癌是亚洲地区发病率最高的肿瘤之一,因此有众多的研究涉及肝细胞癌.然而,在研究中所用统计学方法和技术等不当易得出不正确的概念和结论.作者就已发表在美国<核医学杂志>上的<18F-FDG及11C-乙酸盐PET/CT诊断原发及转移性肝细胞癌的前瞻性研究>一文提出了一些不同观点,希望这方面的研究者能掌握正确的统计学方法、诊断标准及样本人选标准. 相似文献