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61.
Shigeharu Ohyu Mitsuhiro Tozaki Michiro Sasaki Hisae Chiba Qilin Xiao Yasuko Fujisawa Yoshiaki Sagara 《Magnetic resonance in medical sciences》2022,21(3):485
Purpose: We evaluated the diagnostic performance of the texture features of dynamic contrast-enhanced (DCE) MRI for breast cancer diagnosis in which the discriminator was optimized, so that the specificity was maximized via the restriction of the negative predictive value (NPV) to greater than 98%.Methods: Histologically proven benign and malignant mass lesions of DCE MRI were enrolled retrospectively. Training and testing sets consist of 166 masses (49 benign, 117 malignant) and 50 masses (15 benign, 35 malignant), respectively. Lesions were classified via MRI review by a radiologist into 4 shape types: smooth (S-type, 34 masses in training set and 8 masses in testing set), irregular without rim-enhancement (I-type, 60 in training and 14 in testing), irregular with rim-enhancement (R-type, 56 in training and 22 in testing), and spicula (16 in training and 6 in testing). Spicula were immediately classified as malignant. For the remaining masses, 298 texture features were calculated using a parametric map of DCE MRI in 3D mass regions. Masses were classified into malignant or benign using two thresholds on a feature pair. On the training set, several feature pairs and their thresholds were selected and optimized for each mass shape type to maximize specificity with the restriction of NPV > 98%. NPV and specificity were computed using the testing set by comparison with histopathologic results and averaged on the selected feature pairs.Results: In the training set, 27, 12, and 15 texture feature pairs are selected for S-type, I-type, and R-type masses, respectively, and thresholds are determined. In the testing set, average NPV and specificity using the selected texture features were 99.0% and 45.2%, respectively, compared to the NPV (85.7%) and specificity (40.0%) in visually assessed MRI category-based diagnosis.Conclusion: We, therefore, suggest that the NPV of our texture-based features method described performs similarly to or greater than the NPV of the MRI category-based diagnosis. 相似文献
62.
Mari Maeda-Yamamoto Osamu Honmou Masanori Sasaki Akane Haseda Hiroyo Kagami-Katsuyama Toshihiko Shoji Ai Namioka Takahiro Namioka Hirotoshi Magota Shinichi Oka Yuko Kataoka-Sasaki Ryou Ukai Mitsuhiro Takemura Jun Nishihira 《Nutrients》2022,14(12)
The purple-flesh potato (Solanum tuberosum L.) cultivar “Shadow Queen” (SQ) naturally contains anthocyanins. This randomized, double-blind, placebo-controlled study determines whether ingesting purple potatoes increases the number of mesenchymal stem cells (MSC) and improves stress response, a minor health complaint in healthy adults (registration number: UMIN000038876). A total of 15 healthy subjects (ages: 50–70 years) with minor health complaints were randomly assigned to one of two groups. For 8 weeks, the placebo group received placebo potatoes cv. “Haruka” and the test group received test potato cv. SQ containing 45 mg anthocyanin. The MSC count and several stress responses were analyzed at weeks 0 and 8 of the intake periods. The ingestion of a SQ potato did not affect the MSC count but markedly improved psychological stress response, irritability, and depression as minor health complaints compared with “Haruka”. No adverse effects were noted. Hence, an 8-week intake of SQ could improve stress responses. 相似文献
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64.
Shigehiro Karashima Mitsuhiro Kometani Hiromasa Tsujiguchi Hiroki Asakura Shigeru Nakano Mikiya Usukura 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2018,40(2):118-125
Objective: Recent studies have reported a high prevalence of primary aldosteronism (PA) among hypertensive patients. However, few data exist regarding the prevalence of PA in the general population. Therefore, we examined the prevalence of PA in the general population including normotensive subjects. Methods: Plasma renin activity (ng/mL/hr), plasma aldosterone concentration (pg/mL) and aldosterone renin ratio (ARR) were determined in 309 subjects aged >40 years in Horimatsu and Higashi-Matsuho district, Shika-machi, Ishikawa, Japan. Results: Among them, 195 subjects (78 males, mean age: 62 ± 11 years) did not take antihypertensive agents: 113 normotensive subjects and 82 hypertensive subjects. Under these conditions, 68 subjects (13 males, age 62 ± 10 years) had an ARR >200. In 14 subjects who underwent captopril suppression test, PA was documented in 5 subjects, yielding a minimum prevalence of 2.6% in total subjects (1.8% in normotensive subjects and 3.7% in hypertensive subjects). Interestingly, females subjects demonstrated significant differences in ARR between subjects with age <50 (172 ± 105) and those with age 51–60 (388 ± 531), although there were no differences in male subjects. Conclusions: These results demonstrate that PA including normotensive subjects exists more commonly than that expected in the general population. We suggest further investigation about the cause and progression of PA associated with sex and aging. 相似文献
65.
Clinical value of capsule endoscopy for detecting small bowel lesions in patients with intestinal Behçet's disease 下载免费PDF全文
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67.
Tetsuya Katsumori Tatsuya Yoshikawa Yasuteru Sasakura Toshinori Yasumura Mitsuhiro Hisano 《Journal of vascular and interventional radiology : JVIR》2021,32(3):332-338
PurposeTo investigate differences in outcomes of uterine artery embolization (UAE) for leiomyoma when performed during different phases of the menstrual cycle.Materials and MethodsIn this single-institution retrospective analysis, 111 premenopausal patients (median [range] age, 44 [33–52] years) undergoing UAE for symptomatic leiomyoma between June 2014 and February 2020 were included. Twenty-one patients underwent UAE in the menstrual phase (the early follicular phase), 27 in the late follicular phase, and 63 in the luteal phase. Baseline characteristics and technical and peri-procedural outcomes were compared among groups. Leiomyoma infarction on contrast-enhanced magnetic resonance imaging 1 week after UAE and 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire scores, the volume reduction rates of the uterus and largest leiomyoma, follicle stimulating hormone values, adverse events, and amenorrhea, were compared among groups.ResultsA 4-month follow-up was completed for all patients. No significant differences were observed among groups in baseline characteristics or technical and peri-procedural outcomes. There were no significant differences in the multivariate-adjusted 1-week infarction rates of all leiomyoma volumes (P = .161) or multivariate-adjusted 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire symptoms and total scores (P = .864 and P = .798, respectively), the volume reduction rates of the uterus and the largest leiomyoma (P = .865 and P = .965, respectively), and follicle stimulating hormone values (P = .186) among the groups. No significant differences were noted in the 4-month adverse events (P = .260) or amenorrhea (P = .793) among the groups.ConclusionsThe present study demonstrated no significant differences in the outcomes of UAE for leiomyoma when performed during different phases of the menstrual cycle. 相似文献
68.
Hidetaka Tamune Hiroaki Takeya Wakako Suzuki Yasuaki Tagashira Takaie Kuki Mitsuhiro Nakamura 《The American journal of emergency medicine》2013,31(11):1601-1604
BackgroundMeningitis is a common emergency disease. Signs and symptoms easily observed at the bedside are needed because early recognition of the possibility of meningitis is necessary for the decision to perform lumbar puncture. Jolt accentuation of headache has been reported to be the most sensitive diagnostic test; however, limited articles have reproduced its sensitivity.MethodsThis is a single-center retrospective medical record review between 2007 and 2012. We diagnosed meningitis based on the criterion standard that cerebrospinal fluid total cells is more than 5/mm3, in accordance with previous studies. All diagnostic and management decisions including Kernig sign, nuchal rigidity, and jolt accentuation of headache were at the physician's discretion. We calculated the sensitivity and specificity of well-known signs and symptoms of meningitis and, especially, compared the efficacy of jolt accentuation of headache with previous studies.ResultsWe investigated 531 adult patients who were suspected of meningitis and had lumbar puncture performed. Of these patients, 139 had meningitis. Background characteristics and vital signs were not clinically different between the 2 groups, although classic tetralogy of bacterial meningitis (fever, nuchal rigidity, mental disturbance, and headache) was worth investigated. The sensitivity and specificity of jolt accentuation of headache were 63.9% (95% confidence interval, 51.9%-76.0%) and 43.2% (34.7%-51.6%), respectively.ConclusionThe absence of jolt accentuation of headache test cannot, on its own, accurately rule out meningitis in adults. Further studies are warranted to reproduce this result and to discover better bedside diagnostic tests. 相似文献
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70.
Yamada T Murakami Y Muto M Okada T Okamoto M Toyama J Yoshida Y Tsuboi N Ito T Kondo T Inden Y Hirai M Murohara T 《Journal of cardiovascular electrophysiology》2004,15(7):745-751
INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs. 相似文献