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91.
Chuluunbaatar Otgonbaatar Jae-Kyun Ryu Jaemin Shin Ji Young Woo Jung Wook Seo Hackjoon Shim Dae Hyun Hwang 《Korean journal of radiology》2022,23(11):1044
ObjectiveThis study aimed to investigate whether a deep learning reconstruction (DLR) method improves the image quality, stent evaluation, and visibility of the valve apparatus in coronary computed tomography angiography (CCTA) when compared with filtered back projection (FBP) and hybrid iterative reconstruction (IR) methods.Materials and MethodsCCTA images of 51 patients (mean age ± standard deviation [SD], 63.9 ± 9.8 years, 36 male) who underwent examination at a single institution were reconstructed using DLR, FBP, and hybrid IR methods and reviewed. CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and stent evaluation, including 10%–90% edge rise slope (ERS) and 10%–90% edge rise distance (ERD), were measured. Quantitative data are summarized as the mean ± SD. The subjective visual scores (1 for worst -5 for best) of the images were obtained for the following: overall image quality, image noise, and appearance of stent, vessel, and aortic and tricuspid valve apparatus (annulus, leaflets, papillary muscles, and chordae tendineae). These parameters were compared between the DLR, FBP, and hybrid IR methods.ResultsDLR provided higher Hounsfield unit (HU) values in the aorta and similar attenuation in the fat and muscle compared with FBP and hybrid IR. The image noise in HU was significantly lower in DLR (12.6 ± 2.2) than in hybrid IR (24.2 ± 3.0) and FBP (54.2 ± 9.5) (p < 0.001). The SNR and CNR were significantly higher in the DLR group than in the FBP and hybrid IR groups (p < 0.001). In the coronary stent, the mean value of ERS was significantly higher in DLR (1260.4 ± 242.5 HU/mm) than that of FBP (801.9 ± 170.7 HU/mm) and hybrid IR (641.9 ± 112.0 HU/mm). The mean value of ERD was measured as 0.8 ± 0.1 mm for DLR while it was 1.1 ± 0.2 mm for FBP and 1.1 ± 0.2 mm for hybrid IR. The subjective visual scores were higher in the DLR than in the images reconstructed with FBP and hybrid IR.ConclusionDLR reconstruction provided better images than FBP and hybrid IR reconstruction. 相似文献
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Vitexin, orientin and other flavonoids from Spirodela polyrhiza inhibit adipogenesis in 3T3-L1 cells
To investigate the adipogenesis inhibitory effect on lipid accumulation, 3T3-L1 cells were treated with fractions and isolated flavonoids of Spirodela polyrhiza. An ethanol extract of S. polyrhiza was fractionated into three fractions. The butanol soluble fraction (SPB) exhibited potent antiadipogenesis activity and decreased C/EBPα and PPARγ protein expression level in 3T3-L1 cells without significant cytotoxicity. The flavonoids were isolated from SPB and their chemical structures were identified as chrysoeriol (1), apigenin (2), luteolin (3), vitexin (4), cosmosin (5), orientin (6) and luteolin-7-O-β-d-glucoside (7) by spectroscopic analysis. Studies on the adipogenesis and intracellular triglyceride accumulation inhibitory effect showed that compounds 4 and 6 had the highest activity and decreased C/EBPα and PPARγ protein expression level in 3T3-L1 cells. These results suggest that the flavonoids isolated from SPB, especially compounds 4 and 6, contribute to the inhibitory activity of S. polyrhiza in 3T3-L1 cells. 相似文献
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96.
Expression of cyclooxygenase-2 in association with clinicopathological prognostic factors and molecular markers in epithelial ovarian cancer 总被引:15,自引:0,他引:15
OBJECTIVES: This study examines whether expression of COX-2 is associated with clinicopathological features and other molecular markers of ovarian cancer. METHODS: Sixty-four paraffin-embedded tissue specimens were obtained from patients with ovarian cancer who received cytoreductive surgery and combination chemotherapy. Tissue specimens were subjected to immunohistochemical analysis using antibodies to COX-2, p53, and VEGF. RESULTS: Increased COX-2 expression significantly correlated with histologic type (mucinous 5.6% vs. non-mucinous 65.2%, P<0.001). COX-2 expression was also significantly associated with stage, tumor grade, residual disease status, and presence of ascites. COX-2 expression correlated positively with expression of p53 (P=0.006) and VEGF (P=0.025). Although survival was lower in patients with high COX-2 expression than in those without high COX-2 expression (P<0.001), only tumor grade and stage were independent prognostic indicators. In patients with non-mucinous cancer, COX-2 expression correlated with stage (P<0.001) and presence of ascites (P=0.033). CONCLUSIONS: Our results suggest that expression of COX-2 in ovarian cancers is specific to histologic type of tumor and is associated with poor clinicopathologic prognostic factors. Expression of COX-2 also correlates well with expression of p53 and VEGF. 相似文献
97.
Pulmonary atresia with intact ventricular septum (PAIVS) is a rare congenital cardiac anomaly that has been classified into
two types: one is a more frequent type having dysplasia of tricuspid valve (TV) with a small annulus, underdeveloped right
ventricle (RV) with a hypoplastic cavity and a hypertrophic wall; the other type has severe dysplasia of TV and dilatation
of RV, right atrium (RA), and right atrioventricular junction with thinning of the RV wall.
We performed a morphologic study on 11 autopsied hearts with PAIVS, giving particular emphasis to the variation of morphology
of the TV. We could classify these hearts into 3 groups according to the degree of right ventricular development. In the first
group of 7 cases (type I), the RVs were underdeveloped. Thick leaflets, restricted valve apparatus with short chordae, and
small annuli were characteristics of the TV. In the second group of 3 cases (type II), the RVs showed marked enlargement of
the cavity and thinning of the wall. The TV showed redundant, dysplastic, sail-like anterior leaflets, and the downward displacement
of septal leaflet and/or posterior leaflet, which are the findings frequently observed in Ebstein's malformation. The RVs
were dilated and with partially unguarded tricuspid orifice. The septal leaflet of the TV was dysplastic and, in two cases,
the septal leaflet showed chordal structure at the upper surface facing the RA, which is a peculiar finding that has not been
described in the literature. The remaining case was a heart with a moderately developed RV (type III). The TV showed mildly
dysplastic appearance and we classify this as a separate type, because we could expect the best surgical results in this type.
This type had optimal size of RV and the mildest degree of dysplasia of TV. In PAIVS, the morphology of TV correlates well
with the type of the right ventricular development. 相似文献
98.
99.
100.
Jung A Lim Yohan Seo Eun-Joo Choi Sang Gyu Kwak Taeha Ryu Jae Hoon Lee Ki Hyuk Park Woon Seok Roh 《Medicine》2022,101(52)
Lower extremity revascularization (LER) for peripheral artery disease in elderly patients is associated with a high risk of perioperative morbidity and mortality. This study aimed to a conduct retrospective review and propensity score matching analysis to determine whether the use of regional anesthesia (RA) instead of general anesthesia (GA) in geriatric patients undergoing LER for peripheral artery disease results in improved short-term mortality and health outcomes. We reviewed medical records of 1271 patients aged >65 years who underwent LER at our center between May 1998 and February 2016. According to the anesthesia method, patients were grouped in the GA and RA groups. The primary outcome was short-term mortality (7-day and 30-day). The secondary outcomes were 5-year survival rate, intraoperative events, postoperative morbidity, and postoperative length of stay. A propensity score-matched cohort design was used to control for potentially confounding factors including patient demographics, comorbidities, American Society of Anesthesiologists physical status, and preoperative medications. After propensity score matching, 722 patients that received LER under GA (n = 269) or RA (n = 453) were identified. Patients from the GA group showed significantly higher 7-day mortality than those from the RA group (5.6% vs 2.7% P = .048); however, there was no significant difference in 30-day mortality between the groups (GA vs RA: 6.3% vs 3.6%, P = .083). The 5-year survival rate and incidence of arterial and central venous catheter placement or intraoperative dopamine and epinephrine use were significantly higher in the GA group than in the RA group (P < .05). In addition, the frequency of immediate postoperative oxygen therapy or mechanical ventilation support was higher in the GA group (P < .05). However, there was no difference in the postoperative cardiopulmonary and cerebral complications between the 2 groups. These results suggest that RA can reduce intraoperative hemodynamic support and provide immediate postoperative respiratory intensive care. In addition, the use of RA may be associated with better short-term and 5-year survival rates in geriatric patients undergoing LER. 相似文献