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51.
OBJECTIVES: The purpose of this study was to determine the pathologic basis of Q-wave (QW) and non-Q-wave (NQW) myocardial infarction (MI). BACKGROUND: The QW/NQW distinction remains in wide clinical use but the meaning of the difference remains controversial. We hypothesized that measurement of total MI size and transmural extent by late gadolinium enhancement cardiovascular magnetic resonance (CMR) would identify the pathologic basis of QWs. METHODS: A total of 100 consecutive patients with documented previous MI had electrocardiogram and CMR on the same day. Patients with acute MI within seven days were excluded. Left ventricular function and the size and transmural extent of MI were quantified in the three major arterial territories and correlated with the presence of QW. RESULTS: Subendocardial MI showed QW in 28%. Transmural MI showed NQW in 29%. Of all MIs, 48% were at some point transmural, and 99% of these were at some point non-transmural. As MI size and number of transmural segments increased, the probability of QW increased (anterior: total size chi-square = 53, p < 0.0001, transmural extent chi-square = 36, p < 0.0001; inferior: total size chi-square = 16, p = 0.001, transmural extent chi-square = 10, p = 0.001). These findings did not hold for lateral MI. In a multivariate model, the transmural extent of MI was not an independent predictor of QW when total size of MI was removed. The QW/NQW classification was a good test for size of MI (area under receiver operating characteristic curve: anterior 0.90, inferior 0.77). CONCLUSIONS: The QW/NQW distinction is useful, but it is determined by the total size rather than transmural extent of underlying MI.  相似文献   
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Prospective data of 3,120 consecutive patients who had elective coronary artery bypass were analyzed to identify patient profile, cost, outcome and predictors of those readmitted to the intensive care unit. Group A (n=3,002) had a single intensive care unit admission and group B (n=118) were readmitted within 30 days after surgery. Parsonnet score, EuroSCORE, age, body mass index, chronic obstructive airway disease, peripheral vascular disease, renal dysfunction, unstable angina, congestive cardiac failure, and poor left ventricular function were higher in group B. Bypass and crossclamp times were longer, and the prevalence of inotropic and balloon pump support, arrhythmias, myocardial infarction, re-exploration, blood loss and transfusion, cerebrovascular accident, wound infection, sternal dehiscence, and multisystem failure were higher in group B. Despite a 4-fold increase in cost of care, the mortality rate (32.4%) of patients readmitted to intensive care was 23-times higher than routine patients (1.4%). Crossclamp time>80 min, Parsonnet score>10, EuroSCORE>9, sternal dehiscence, ventricular arrhythmias, and renal failure predicted readmission.  相似文献   
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Urea cycle disorders (UCD) are common during neonatal period, and it is rarely reported in adults. We are reporting a patient presenting with post-partum neuropsychiatric symptoms rapidly progressing to coma. Markedly raised serum ammonia level on presentation with an initial normal magnetic resonance imaging (MRI) of brain and normal liver function tests led to the suspicion of UCD, which was confirmed on the basis of urine orotic acid and elevated serum amino acid levels. We had to resort to hemodialysis to correct the hyperammonemic coma, which was unresponsive to conventional anti-ammonia measures. She exhibited remarkable improvement with a progressive decline in serum ammonia with repeated hemodialysis and made a full recovery. Timely diagnosis and early institution of hemodialysis in the setting of a poor neurological status maybe considered a suitable treatment option.  相似文献   
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Biochar carbon YP-50 exposed to gamma radiation at 50 kGy, 100 kGy, and 150 kGy was used as an electrode for an electric double-layer capacitor. The gamma radiation affected the pore structure and pore volume of the biochar electrodes. The optimized surface morphology, pore structure, and pore volume of the biochar with an irradiation dose of 100 kGy showed outstanding specific capacitance of 246.2 F g−1 compared to the untreated biochar (115.3 F g−1). The irradiation dose of 100 kGy exhibited higher specific power and specific energy of 0.1 kW kg−1 and 34.2 W h kg−1 respectively, with a capacity retention of above 96% after 10 000 cycles at a current density of 2 A g−1. This improvement can be attributed to the decrease in average particle size, an increase in the porosity of biochar carbon. Besides, the charge transfer resistance of supercapacitor is significantly reduced from 21.7 Ω to 7.4 Ω after treating the biochar carbon with 100 kGy gamma radiation, which implies an increase in conductivity. This gamma radiation strategy to pretreat the carbon material for improving the properties of carbon materials can be promising for the development of high-performance supercapacitors for large-scale applications.

(a) Schematic of the biochar carbon YP-50 exposed to gamma radiation. (b) Cyclic Voltammetry of supercapacitor with untreated biochar and biochar treated with 50 kGy, 100 kGy, and 150 kGy gamma-radiation.  相似文献   
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Objective:

The purpose of the study was to evaluate the spectrum and incidence of intrahepatic portal vein (PV) variations on triphasic abdomen multidetector CT (MDCT) and to discuss the surgical and radiological implications.

Methods:

A retrospective review of 1000 triphasic MDCT abdomen scans was performed in patients sent for various liver and other abdominal pathologies between January 2014 and August 2014. A total of 967 patients (N = 967) were included in the study. The variations in branching pattern of PV were classified according to classification used by Covey et al (Covey AM, Brody LA, Getrajdman GI, Sofocleous CT, Brown KT. Incidence, patterns, and clinical relevance of variant portal vein anatomy. AJR Am J Roentgenol 2004; 183: 1055–64) and Koç et al (Koç Z, Oğuzkurt L, Ulusan S. Portal vein variations: clinical implications and frequencies in routine abdominal CT. Diagn Interv Radiol 2007; 13: 75–80).

Results:

Normal anatomy (Type I) was seen in 773 patients (79.94%) out of 967 patients in our study. Trifurcation (Type II) anomaly was seen in 66 (6.83%) of cases. Right posterior vein as first branch of main PV (Type III) anomaly was seen in 48 (4.96%) of cases. Type IV anomaly and Type V anomaly was seen in 26 (2.69%) and 13 (1.34%) cases, respectively. 19 cases showed other types of variations.

Conclusion:

Variations in the hepatic PV branching patterns are commonly seen that are similar to variations in hepatic artery and biliary anatomy. Knowledge of these variations is extremely important for transplant surgeons and intervention radiologists.

Advances in knowledge:

Awareness of the variations in PV branching patterns is essential for intervention radiologists and vascular surgeons and avoids major catastrophic events.  相似文献   
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