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Cyclic variation (CV) of myocardial integrated backscatter (IBS), which reflects intrinsic contractile performance, can predict myocardial viability in patients with a reperfused acute myocardial infarction (MI), but the use of this method has not been validated for chronic left ventricular (LV) dysfunction. The aim of this study was to examine whether myocardial IBS was useful for predicting LV functional recovery after coronary revascularization in 17 patients with prior anterior MI and LV dysfunction (ejection fraction <50%). Within 24 h of the revascularization procedure (percutaneous transluminal coronary angioplasty or coronary stenting), IBS curves were obtained by placing the region of interest on the anterior wall on the short-axis IBS image. The patients had repeat left heart catheterization at 3 or 6 months after the revascularization procedure, and were grouped according to the patterns of the IBS curve within the anterior wall. In 8 patients (group A), the IBS curve had a synchronized pattern with the magnitude of CV > or = 3.5, and in the remaining 9 patients (group B), the curve had either an asynchronized pattern or the magnitude of CV was less than 3.5 dB even in the case of synchronized pattern, or both. At baseline, there were no significant differences in LV functional indices between the 2 groups. After the follow-up period, the LV end-systolic volume decreased (75 +/- 21 ml to 56 +/- 20ml, p = 0.05), LV ejection fraction increased (35 +/- 12% to 50 +/- 14%, p = 0.014), and LV end-diastolic pressure decreased (19 +/- 10 mmHg to 13 +/- 6 mmHg, p = 0.02) in group A, whereas only the LV ejection fraction increased (34 +/- 9% to 40 +/- 11%, p = 0.03) in group B; LV end-systolic volume (72 +/- 19 ml to 66 +/- 16 ml, p = 0.126) and LV end-diastolic pressure (18 +/- 12 mmHg to 14 +/- 8 mmHg, p = 0.184) showed no significant changes. In conclusion, IBS is valuable for predicting LV functional recovery after coronary revascularization in patients with LV dysfunction caused by a remote anterior MI. A large-scale study is be needed to establish these data.  相似文献   
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Subjects with persistent left superior vena cava were classified on the basis of the presence and thickness of both superior venae cavae, the anastomotic ramus between the superior venae cavae (anastomotic ramus), and the presence of both azygos veins. Among subjects with persistent left superior vena cava, the percentage of those with weak development of the anastomotic ramus (41.5?%) or absence of an anastomotic ramus (35.8?%) was 77.3?%. In addition, 54.7?% of subjects had a left azygos vein. However, 88.7?% of subjects had a right azygos vein. In this classification, the most frequently observed types included the presence of both superior venae cavae, an anastomotic ramus, and both azygos veins (20.8?%). During student dissection practice sessions performed on 337 cadavers that were carried out from 2002 through 2010, a subject having a left superior vena cava (in 2002) and a subject having both superior venae cavae (in 2003) were detected. The former case was reported previously. The latter case is reported in this paper. The incidence of persistent left superior vena cava was 0.59?% (2/337 cadavers).  相似文献   
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Cisplatin (CDDP) is an anticancer drug. The clinical limitations associated with CDDP have stimulated the development of macromolecular drug-carrier systems, in attempts to decrease its toxicity. A complex (CDDP-CSA-23) between CDDP and chondroitin sulfate (CSA), a natural polysaccharide with a mean molecular weight of 23 kDa, proved to have the same anticancer activity as CDDP. A toxicodynamic study was performed on perfused kidneys to determine the effect of CDDP-CSA-23 on renal functions and the extent of platinum accumulation. The results showed that CDDP-CSA-23 attenuates the reduction in urine flow and creatinine clearance induced by CDDP. Moreover, significantly lower amounts of platinum were excreted into the urine in the case of CDDP-CSA-23, compared with CDDP alone. Meanwhile, CDDP-CSA-23 effectively retarded the rapid perfusion of platinum into kidney tissues, as occurs when CDDP is being perfused alone. The cytoprotective effects of CDDP-CSA on human proximal tubular (HK-2) cells were examined by measuring the growth of HK-2 cells in the presence of CDDP or CDDP-CSA-23. Interestingly, CDDP-CSA-23 was found to have a significantly reduced cytotoxicity, compared to CDDP. These results suggest that CDDP-CSA-23 greatly decreased the negative effects of CDDP on glomerular filtration and tubular transport in kidneys at early stages of its administration.  相似文献   
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ObjectivesTo examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires.Materials and MethodsThis study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5–40° were examined.ResultsThe torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires.ConclusionsThe current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires.  相似文献   
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Blonanserin is a novel antipsychotic agent that preferentially interacts with dopamine D2 and 5-HT2A receptors. To assess the atypical properties of blonanserin, we evaluated its propensity to induce extrapyramidal side effects (EPS) and to enhance forebrain Fos expression in mice. The actions of AD-6048, a primary metabolite of blonanserin, in modulating haloperidol-induced EPS were also examined. Blonanserin (0.3-10 mg/kg, p.o.) did not significantly alter the pole-descending behavior of mice in the pole test or increase the catalepsy time, while haloperidol (0.3-3 mg/kg, p.o.) caused pronounced bradykinesia and catalepsy. Blonanserin and haloperidol at the above doses significantly enhanced Fos expression in the shell (AcS) region of the nucleus accumbens and dorsolateral striatum (dlST). The extent of blonanserin-induced Fos expression in the AcS was comparable to that induced by haloperidol. However, the striatal Fos expression by blonanserin was less prominent as compared to haloperidol. Furthermore, combined treatment of AD-6048 (0.1-3 mg/kg, s.c.) with haloperidol (0.5 mg/kg, i.p.) significantly attenuated haloperidol-induced bradykinesia and catalepsy. The present results show that blonanserin behaves as an atypical antipsychotic both in inducing EPS and enhancing forebrain Fos expression. In addition, AD-6048 seems to contribute at least partly to the atypical properties of blonanserin.  相似文献   
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