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排序方式: 共有9174条查询结果,搜索用时 9 毫秒
91.
92.
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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94.
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
95.
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
96.
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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
99.
Developing a high-performing hydrogel with long-lasting skin adhesion, high ionic conductivity, mechanical stability, and fatigue resistance is a crucial issue in the field of wearable electronic devices. Because of their weak mechanical properties, zwitterion-based hydrogels are not suitable for application in wearable strain sensors despite their excellent adhesion to the skin. In this study, a hydrogel of polymer without additive was prepared by using polymerizable monomers consisting of zwitterionic 3-(1-vinyl-3-imidazolio)propanesulfonate (VIPS), anionic 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPSs), and acrylamide (AAm); the hydrogel is abbreviated as P(AMPSs/VIPS-co-AAm). The P(AMPSs/VIPS-co-AAm) hydrogel shows exceptional adhesive strength, reaching up to 26.29 kPa (lap shear to porcine skin) and high stretchability (with a fracture strain of 1282% and stress of 40 kPa). The high polarity of the AMPSs/VIPS pair improves the interfacial adhesion to the skin, the internal cohesion and recovery tendency. Unique structural characteristics of the hydrogel impart excellent fatigue resistance, network toughening, and electrical stability after multiple deformations. Thus, the prepared hydrogel has an ionic conductivity (0.51 S m−1), strain sensitivity, and long-term skin adhesion, and it demonstrates potential to be applied for wearable strain sensors.Developing a high-performing hydrogel with long-lasting skin adhesion, high ionic conductivity, mechanical stability, and fatigue resistance is a crucial issue in the field of wearable electronic devices. 相似文献
100.
Jin-Hui Choi Bon-Hoon Koo Wan-Seok Seo Eun-Jin Cheon Hyung-Mo Sung Ji Yean Kim Hyun-Seok Jeong Younggyo Kim Hye-Geum Kim 《Psychiatry investigation》2023,20(2):109
ObjectiveThis study aimed to explore the characteristics and factors related to changes in cognitive function in vulnerable individuals with cognitive impairment during the coronavirus disease 2019 (COVID-19) pandemic.MethodsAmong patients who visited a local university hospital with subjective cognitive complaints, those who had been tested for cognitive function at least once after the onset of COVID-19 and tested regularly at least three times within the last 5 years were included (1st, the initial screening; 2nd, the test immediately before the COVID-19 pandemic; 3rd, the most recent test after the pandemic). Finally, 108 patients were included in this study. They were divided into groups according to whether the Clinical Dementia Rating (CDR) was maintained/improved and deteriorated. We investigated the characteristics of the changes in cognitive function and related factors during COVID-19.ResultsWhen comparing CDR changes before and after COVID-19, there was no significant difference between the two groups (p=0.317). Alternatively, the main effect of the time when the test was conducted was significant (p<0.001). There was also a significant difference in the interaction between the groups and time. When the effect of the interaction was analyzed, the CDR score of the maintained/improved group significantly decreased before COVID-19 (1st–2nd) (p=0.045). After COVID-19 (2nd–3rd), the CDR score of the deteriorated group was significantly higher than that of the maintained/improved group (p<0.001). Mini-Mental State Examination recall memory and changes in activity during COVID-19 were significantly associated with CDR deterioration.Conclusion Memory dysfunction and decreased activity during the COVID-19 pandemic are strongly related to the deterioration of cognitive impairment. 相似文献