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排序方式: 共有5452条查询结果,搜索用时 15 毫秒
41.
Jung SI Lee YH Moon MH Song MJ Min JY Kim JA Park JH Yang JH Kim MY Chung JH Cho JY Kim KG 《Prenatal diagnosis》2007,27(6):545-551
OBJECTIVE: To construct new reference charts and equations for fetal biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur diaphysis length (FDL) from Korean fetuses at 12-40 weeks. METHOD: Prospective cross-sectional data obtained in one center for 5 years from a population of pregnant women undergoing ultrasound examination between the 12th and 40th week of gestation. Exclusion criteria comprised all maternal and fetal conditions possibly affecting fetal biometry. No fetuses were excluded on the basis of abnormal biometry. For each measurement, regression models were fitted to estimate both the mean and the standard deviation at each menstrual age. RESULTS: Biometric measurements were obtained for 10 455 fetuses. New charts and reference equations are reported for BPD, HC, AC and FDL. Reference equations are cubic models. CONCLUSION: We present new Korean reference charts and equations for fetal biometry. They can be easily used in obstetric ultrasound studies for the Korean population. 相似文献
42.
Chung HH Kang SB Cho JY Kim JW Park NH Song YS Kim SH Lee HP 《Gynecologic oncology》2007,104(3):654-659
OBJECTIVES: To retrospectively evaluate the accuracy of magnetic resonance (MR) imaging for the prediction of depth of myometrial invasion in the preoperative assessment of women with endometrial carcinoma. METHODS: We retrospectively reviewed the medical records and MR imaging reports of 120 women with pathologically-proven endometrial carcinoma who underwent preoperative pelvic MR imaging between June 1997 and February 2006. Tumor signal intensity, the appearance of the junctional zone (JZ), the presence of large polypoid tumors and leiomyomas were analyzed. Univariate logistic-regression analysis was performed to identify associations between incorrect MR staging and the study variables. RESULTS: Data from 120 patients were registered for the current study and analyzed. The sensitivity, specificity and accuracy of the MR imaging in assessment of myometrial invasion among patients with endometrial carcinoma were: 50.6%, 89.2% and 62.5% respectively. MR differentiation of deep myometrial invasion from superficial disease had an 83.3% accuracy (100 of 120 cases). Isointense JZ to myometrium (P<0.001), and the presence of polypoid tumors (P=0.037) on MR imaging were significantly associated with an underestimation of myometrial invasion by endometrial carcinoma. CONCLUSIONS: Isointense JZ to myometrium and polypoid tumors are difficult to accurately evaluate for myometrial invasion of endometrial carcinoma by MR imaging. 相似文献
43.
OBJECTIVES: The purpose of our study is to provide reference values for the great vessels obtained from images of the three-vessel view of the fetal heart, with an emphasis on the size discrepancy of the great vessels. METHODS: From February 2003 to May 2003, the main pulmonary artery (MPA), ascending aorta (AA), and SVC were measured in well-dated, nonanomalous fetuses scanned at 14-38 weeks of gestation. RESULTS: The size of each great vessel had a significant positive relationship with advance in gestation (P < 0.001); MPA (mm) = -2.76 + 0.34 x GA, ascending aorta (AA) (mm) = -1.73 + 0.26 x GA - 1.18E - 05 x GA(3), and SVC (mm) = 0.33 + 0.01 x GA(2) - 4.12E - 05 x GA(3). The AA/MPA ratio was significantly decreased with advance in gestation, while the SVC/AA ratio was significantly increased; AA/MPA ratio = -1.24 - 0.03 x GA + 3.88E - 04 x GA(2); P < 0.001, SVC/AA ratio = 0.63 - 5.43E - 03 x GA + 1.96E - 04 x GA(2); P < 0.001. CONCLUSION: On the three-vessel view of the fetal heart, the interpretation of the size discrepancy of the great vessels needs to be adjusted according to fetal growth. 相似文献
44.
Yoo Na Jang Yong Jik Lee Yoon Mi Han Hyun Min Kim Hong Seog Seo Ji Hoon Jeong Seung Yeon Park Tae Woo Jung 《Yonsei medical journal》2022,63(6):530
PurposeSince diabetes and hypertension frequently occur together, it is thought that these conditions may have a common pathogenesis. This study was designed to evaluate the anti-diabetic function of the anti-hypertensive drug fimasartan on C2C12 mouse skeletal muscle and HepG2 human liver cells in a high glucose state.Materials and MethodsThe anti-diabetic effects and mechanism of fimasartan were identified using Western blot, glucose uptake tests, oxygen consumption rate (OCR) analysis, adenosine 5′-triphosphate (ATP) enzyme-linked immunosorbent assay (ELISA), and immunofluorescence staining for diabetic biomarkers in C2C12 cells. Protein biomarkers for glycogenolysis and glycogenesis were evaluated by Western blotting and ELISA in HepG2 cells.ResultsThe protein levels of phosphorylated 5′ adenosine monophosphate-activated protein kinase (p-AMPK), p-AKT, insulin receptor substrate-1 (IRS-1), and glucose transporter type 4 (Glut4) were elevated in C2C12 cells treated with fimasartan. These increases were reversed by peroxisome proliferator-activated receptor delta (PPARδ) antagonist. ATP, OCR, and glucose uptake were increased in cells treated with 200 µM fimasartan. Protein levels of glycogen phosphorylase, glucose synthase, phosphorylated glycogen synthase, and glycogen synthase kinase-3 (GSK-3) were decreased in HepG2 cells treated with fimasartan. However, these effects were reversed following the addition of the PPARδ antagonist GSK0660.ConclusionIn conclusion, fimasartan ameliorates deteriorations in glucose metabolism as a result of a high glucose state by regulating PPARδ in skeletal muscle and liver cells. 相似文献
45.
While ultrasound (US) is considered an important tool for hepatocellular carcinoma (HCC) surveillance, it has limited sensitivity for detecting early-stage HCC. Abbreviated MRI (AMRI) has recently gained popularity owing to better sensitivity in its detection of early-stage HCC than US, while also minimizing the time and cost in comparison to complete contrast-enhanced MRI, as AMRI includes only a few essential sequences tailored for detecting HCC. Currently, three AMRI protocols exist, namely gadoxetic acid-enhanced hepatobiliary-phase AMRI, dynamic contrast-enhanced AMRI, and non-enhanced AMRI. In this study, we discussed the rationale and technical details of AMRI techniques for achieving optimal surveillance performance. The strengths, weaknesses, and current issues of each AMRI protocol were also elucidated. Moreover, we scrutinized previously performed AMRI studies regarding clinical and technical factors. Reporting and recall strategies were discussed while considering the differences in AMRI protocols. A risk-stratified approach for the target population should be taken to maximize the benefits of AMRI and the cost-effectiveness should be considered. In the era of multiple HCC surveillance tools, patients need to be fully informed about their choices for better adherence to a surveillance program. 相似文献
46.
Hye Yeon Cho Chung Mu Park Mi Jeong Kim Radnaabazar Chinzorig Chung Won Cho Young Sun Song 《Nutrition Research And Practice》2011,5(5):381-388
We compared the effects of genistein and daidzein on the expression of chemokines, cell adhesion molecules (CAMs), and endothelial nitric oxide synthase (eNOS) in tumor necrosis factor (TNF)-α-stimulated human umbilical vascular endothelial cells (HUVECs). TNF-α exposure significantly increased expression of monocyte chemoattractant protein (MCP)-1, vascular adhesion molecule (VCAM)-1, and intercellular adhesion molecule-1. Genistein significantly decreased MCP-1 and VCAM-1 production in a dose-dependent manner, whereas CAM expression was not significantly lowered by genistein treatment. However, daidzein slightly decreased MCP-1 production. The effects of genistein and daidzein on MCP-1 secretion coincided with mRNA expression. Pre-treatment with either genistein or daidzein elevated eNOS expression and nitric oxide production disturbed by TNF-α exposure. A low concentration of isoflavones significantly inhibited nuclear factor (NF)κB activation, whereas a high dose slightly ameliorated these inhibitive effects. These results suggest that genistein had a stronger effect on MCP-1 and eNOS expression than that of daidzein. Additionally, NFκB transactivation might be partially related to the down-regulation of these mRNAs in TNF-α-stimulated HUVECs. 相似文献
47.
Felix G. Meinel Julian L. Wichmann U. Joseph Schoepf Francesca Pugliese Ullrich Ebersberger Gladys G. Lo Yeon Hyeon Choe Yining Wang Christian Tesche Sabrina Segreto Wolfgang G. Kunz Kolja M. Thierfelder Fabian Bamberg Carlo N. De Cecco 《Journal of Cardiovascular Computed Tomography》2017,11(1):16-24
Background
There is no published data on the prognostic value of global myocardial perfusion values at stress dynamic CT myocardial perfusion imaging (CTMPI).Methods
Data of 144 patients from 6 centers who had undergone coronary CT angiography (coronary CTA) and CTMPI were assessed. Coronary CTA studies were acquired at rest; CTMPI was performed under vasodilator stress. Coronary CTA data were evaluated for coronary artery stenosis (≥50% luminal narrowing) on a per-vessel basis. Volumes-of-interest were placed over the entire left ventricular myocardium to obtain global myocardial blood flow (MBF), myocardial blood volume (MBV), and volume transfer constant (Ktrans). Follow-up was obtained at 6/12/18 months. Major adverse cardiac events (MACE, defined as cardiac death, non-fatal myocardial infarction, unstable angina requiring hospitalization, and revascularization) served as the endpoint.Results
MACE occurred in 40 patients (nonfatal myocardial infarction, n = 1, unstable angina, n = 13, PCI, n = 23, and CABG, n = 3). Patients with global MBF of <121 mL/100 mL/min were at increased risk for MACE (HR 2.07, 95% confidence interval [CI]: 1.12–3.84, p = 0.02). This association remained significant after adjusting for age, gender, and clinical risk factors (HR 2.17, 95%CI: 1.16–4.06, p = 0.02), after further adjusting for presence of ≥50% stenosis at coronary CTA (HR 2.18, 95%CI: 1.16–4.10, p = 0.02) and when excluding early (<6 months) revascularizations (HR 2.34, 95%CI: 1.01–5.43, p = 0.0486). Global MBV and Ktrans were not independent predictors of MACE.Conclusion
Global quantification of left ventricular MBF at stress dynamic CTMPI may have incremental predictive value for future MACE over clinical risk factors and assessment of stenosis at coronary CTA. 相似文献48.
Unusual gastric tumors: radiologic-pathologic correlation. 总被引:12,自引:0,他引:12
S H Park J K Han T K Kim J W Lee S H Kim Y I Kim B I Choi K M Yeon M C Han 《Radiographics》1999,19(6):1435-1446
The overlap of radiologic findings in many gastric tumors makes differentiation difficult. However, some unusual gastric tumors have characteristic radiologic features that may suggest a specific diagnosis. At barium study, lipomas typically manifest as a smooth submucosal mass or an ulcerated lesion with a "bull's-eye" appearance that is indistinguishable from other mesenchymal tumors. At computed tomography (CT), lipomas usually manifest as well-circumscribed submucosal masses with fat attenuation. At radiology, glomus tumors appear as smooth submucosal masses with or without ulceration and may contain tiny flecks of calcification. These tumors frequently demonstrate strong enhancement on early-phase contrast material-enhanced images. At barium study, lymphangiomas may appear as smooth intramural masses that are indistinguishable from other mesenchymal tumors. At CT, they manifest as non-enhancing extramucosal masses with homogeneous low attenuation. Diffuse lesions in Brunner gland hamartoma manifest as multiple small nodules, producing a characteristic "cobblestone" appearance. Lymphomas may have typical imaging features (eg, more pronounced and homogeneous mural thickening) that can help differentiate them from adenocarcinoma. In addition, adenocarcinomas may demonstrate unusual findings such as transpyloric spread, unusually large polyps, or intratumoral calcifications. Familiarity with these radiologic features of gastric tumors can help ensure correct diagnosis and proper management. 相似文献
49.
Total arch repair versus hemiarch repair in the management of acute DeBakey type I aortic dissection
Joon Bum Kim Cheol Hyun Chung Duk Hwan Moon Geong Jun Ha Taek Yeon Lee Sung Ho Jung Suk Jung Choo Jae Won Lee 《European journal of cardio-thoracic surgery》2011,40(4):881-887
Objective: In acute DeBakey type I aortic dissection, it is still controversial whether to perform extended aortic replacement to improve long-term outcome or to use a conservative strategy with ascending aortic and hemiarch replacement to palliate a life-threatening condition. Methods: Between 1999 and 2009, 188 consecutive patients (93 women; mean age, 57.4 ± 11.7 years) with acute DeBakey type I aortic dissection underwent hemiarch (Hemiarch group; n = 144) or total arch replacement (Total arch group; n = 44) in conjunction with ascending aorta replacement. Clinical outcomes were compared after adjustment for baseline characteristics using inverse-probability-of-treatment weighting. Results: Median follow-up was 47.5 months (range 0–130.4 months) and was 92.0% (n = 173) complete. Five-year unadjusted survival and permanent-neurologic-injury-free survival rates were 65.8 ± 8.3% and 43.1 ± 9.7% in the Total arch group, and 83.2 ± 3.3% and 75.2 ± 4.0% in the Hemiarch group, respectively (P = 0.013 and <0.001). After adjustment, the Total arch group patients were at greater risks of death (hazard ratio (HR) 2.38, 95% confidence interval (CI) 1.21–4.67; P = 0.012), and permanent neurologic injury (HR 3.25, 95% CI 1.31–8.04; P = 0.011) compared to the Hemiarch group patients. The risks of the re-operation for aortic pathology or distal aortic dilatation (>55 mm) were similar for both groups (HR 0.33, 95% CI 0.08–1.43; P = 0.14). Conclusions: Total arch repair was associated with greater morbidity and mortality compared with hemiarch repair in acute DeBakey type I aortic dissection. Rates of aortic re-operation or aortic dilatation were not significantly different between the two surgical strategies. These findings support a conservative surgical approach to circumvent this life-threatening situation. 相似文献
50.