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31.
Iichiro Osawa Eito Kozawa Yuya Yamamoto Sayuri Tanaka Taira Shiratori Akane Kaizu Kaiji Inoue Mamoru Niitsu 《Magnetic resonance in medical sciences》2022,21(3):469
Purpose: The purpose of the present study was to evaluate contrast enhancement of the infundibular recess in the normal state using heavily T2-weighted 3D fluid-attenuated inversion recovery (FLAIR) (HT2-FLAIR).Methods: Twenty-six patients were retrospectively recruited. We subjectively assessed overall contrast enhancement of the infundibular recess between postcontrast, 4-hour (4-h) delayed postcontrast, and precontrast HT2-FLAIR images. We also objectively conducted chronological and spatial comparisons by measuring the signal intensity (SI) ratio (SIR). Chronological comparisons were performed by comparing SI of the infundibular recess/SI of the midbrain (SIRIR-MB). Spatial comparisons were conducted by comparing SI on postcontrast HT2-FLAIR/SI on precontrast HT2-FLAIR (SIRPost-Pre) of the infundibular recess with that of other cerebrospinal fluid (CSF) spaces, including the superior part of the third ventricle, lateral ventricles, fourth ventricle, and interpeduncular cistern.Results: In the subjective analysis, all cases showed contrast enhancement of the infundibular recess on both postcontrast and 4-h delayed postcontrast HT2-FLAIR, and showed weaker contrast enhancement of the infundibular recess on 4-h delayed postcontrast HT2-FLAIR than on postcontrast HT2-FLAIR. In the objective analysis, SIRIR-MB was the highest on postcontrast images, followed by 4-h delayed postcontrast images. SIRPost-Pre was significantly higher in the infundibular recess than in the other CSF spaces.Conclusion: The present results demonstrated that the infundibular recess was enhanced on HT2-FLAIR after an intravenous gadolinium injection. The infundibular recess may be a potential source of the leakage of intravenously administered gadolinium into the CSF. 相似文献
32.
Murata T Miyase T Muregi FW Naoshima-Ishibashi Y Umehara K Warashina T Kanou S Mkoji GM Terada M Ishih A 《Journal of natural products》2008,71(2):167-174
From the stem bark of Ekebergia capensis, 10 new triterpenoid compounds, ekeberins A (1), B (2), C1 (3), C2 (4), C3 (5), D1 (6), D2 (7), D3 (8), D4 (9), and D5 (10), were isolated together with 17 known compounds. The structures of these new compounds were elucidated on the basis of the results of spectroscopic analysis, and the absolute configuration of compounds 6-10 were determined by partial synthesis from known compounds and using the Mosher ester method. Several of these compounds were screened in vitro against both chloroquine (CQ)-sensitive and -resistant Plasmodium falciparum isolates and were found to exhibit moderate antiplasmodial activity, with compounds 20 (7-deacetoxy-7-oxogedunin) and 27 (2-hydroxymethyl-2,3,22,23-tetrahydroxy-2,6,10,15,19,23-hexamethyl-6,10,14,18-tetracosatetraene) showing IC50 values of 6 and 7 microM, respectively. Compound 27 at a dose of 500 mg/kg showed moderate parasitemia suppression of 52.9% against P. berghei NK 65 in a mouse model. 相似文献
33.
Tomozumi Takatani Yuzuka Kunii Mamoru Satoh Akifumi Eguchi Midori Yamamoto Kenichi Sakurai Rieko Takatani Fumio Nomura Naoki Shimojo Chisato Mori 《Nutrients》2022,14(11)
Existing evidence on the correlation between maternal vitamin D concentrations and birth outcomes is conflicting. Investigation of these associations requires accurate assessment of vitamin D status, especially in individuals with low 25-hydroxyvitamin D (25(OH)D) concentrations. This study examined the correlations between birth outcomes and the maternal vitamin D metabolite ratio (VMR) 1 (defined as the ratio of 24,25(OH)2D3 to 25(OH)D) and VMR2 (defined as the ratio of 3-epi-25(OH)D3 to 25(OH)D) using data from the Japan Environment and Children’s Study at Chiba Regional Center. A total of 297 mother–neonate pairs were analyzed. Using liquid chromatography–tandem mass spectrometry, we measured 25(OH)D2, 25(OH)D3, 24,25(OH)2D3, and 3-epi-25(OH)D3 concentrations in maternal serum samples. These data were analyzed in relation to birth anthropometric data using multivariable linear regression. Of the study participants, 85.2% showed insufficient vitamin D concentrations. VMR1 was strongly correlated with 25(OH)D concentrations, whereas VMR2 showed a weak correlation. Only VMR2 was associated with all anthropometric data. VMR2 in pregnant women with low vitamin D blood concentrations is a useful marker for neonatal anthropometric data and is independent of 25(OH)D. Accurate measurement of vitamin D metabolites could help better understand the effects of vitamin D on birth outcomes. 相似文献
34.
Shizukuishi K Watanabe H Narita H Kanaya S Kobayashi K Yamamoto T Tsukada M Iwanaga T Ikebuchi S Kusama K Tanaka M Namiki N Fuiimura Y Horikoshi A Inoue T Kusakabe K;Working Group of Ministry of Health Labour Welfare for Study about Fitness Management;of Medical Radioactive Waste 《Kaku igaku. The Japanese journal of nuclear medicine》2004,41(2):109-121
We conducted a questionnaire survey about radiation-safety management condition in Japanese nuclear medicine facilities to make materials of proposition for more reasonable management of medical radioactive waste. We distributed a questionnaire to institutions equipped with Nuclear Medicine facilities. Of 1,125 institutions, 642 institutes (52.8%) returned effective answers. The questionnaire covered the following areas: 1) scale of an institution, 2) presence of enforcement of radiotherapy, 3) system of a tank, 4) size and number of each tank, 5) a form of draining-water system, 6) a displacement in a radioactive rays management area, 7) a measurement method of the concentration of medical radioactive waste in draining water system, 8) planned and used quantity of radioisotopes for medical examination and treatment, 9) an average displacement of hospital for one month. In most institutions, a ratio of dose limitation of radioisotope in draining-water system was less than 1.0, defined as an upper limitation in ordinance. In 499 hospitals without facilities of hospitalization for unsealed radioisotope therapy, 473 hospitals reported that sum of ratios of dose limits in a draining-water system was less than 1.0. It was calculated by used dose of radioisotope and monthly displacement from hospital, on the premise that all used radioisotope entered in the general draining-water system. When a drainage including radioactivity from a controlled area join with that from other area before it flows out of a institution, it may be diluted and its radioactive concentration should be less than its upper limitation defined in the rule. Especially, in all institutions with a monthly displacement of more than 25,000 m3, the sum of ratio of the concentration of each radionuclide to the concentration limit dose calculated by used dose of radioisotope, indicated less than 1.0. 相似文献
35.
Kochi Masatoshi Hinoi Takao Niitsu Hiroaki Ohdan Hideki Konishi Fumio Kinugasa Yusuke Kobatake Takaya Ito Masaaki Inomata Masafumi Yatsuoka Toshimasa Ueki Takashi Tashiro Jo Yamaguchi Shigeki Watanabe Masahiko 《Surgery today》2018,48(8):756-764
Surgery Today - Postoperative pneumonia affects the length of stay and mortality after surgery in elderly patients with colorectal cancer (CRC). We aimed to determine the risk factors of... 相似文献
36.
In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a magnitude of 100 grams and a moment of 550 g·mm in a du-ration of 3 to 56 days.Then sections were prepared for histological examination.The findings re-vealed that,due to tooth rotation,neighboring teeth were drifted and rotated(82%),and therewere disarrangement and hyalinization of the periodontal ligament(88%),remodeling of the pe-riodontium(86%)and root resorption(32%)were also observed.These results demonstratethat tooth rotation may exert marked effects on neighboring teeth and periodontal tissues,whichmay be of important clinical significance. 相似文献
37.
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39.
Eiji Wada Mitsuru Fukui Kazuhisa Takahashi Daisaku Takeuchi Hiroshi Hashizume Masahiko Kanamori Noboru Hosono Tsukasa Kanchiku Yuichi Kasai Miho Sekiguchi Shin-ichi Konno Mamoru Kawakami Kazuo Yonenobu 《Journal of orthopaedic science》2019,24(1):57-61
Background
In 1999, the Japanese Orthopaedic Association decided to develop a new Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). The final version of the JOACMEQ, comprising 24 questions and five domains (cervical spine function (CF); upper extremity function (UF); lower extremity function (LF); bladder function (BF); and quality of life (QOL)), was established after three nationwide investigations. The fourth investigation, reported in this paper, was performed to confirm the responsiveness of the questionnaire.Methods
A total of 137 patients with cervical myelopathy were included in the study. Each patient was interviewed twice using the JOACMEQ before and after treatment. At the second interview, the patients self-rated their condition in five domains for “worse,” “somewhat worse,” “no change,” “somewhat better,” or “better,” and these scores were defined as the external assessment rating. The difference of the points in five domains between the first and the second interview was calculated against each external assessment. Based on the results, substantial clinical benefit (SCB) thresholds for the JOACMEQ were determined.Results
The statistically significant median values of the acquired points were 17.5 for CF, 16.0 and 21.0 for UF, 27.0 and 20.5 for LF, 13.0 for BF, and 29.0 for QOL. After consideration of the results, the committee decided that an acquired point ≥20 could be interpreted as representing an SCB threshold for the JOACMEQ.Conclusion
We have concluded that a treatment can be judged to be effective for a patient if 1) The patient give all answers for the questions necessary to calculate the functional score of a domain and an increase of ≥20 points is obtained for that score, or 2) The functional score after treatment is > 90 points even if the answer for the unanswered questions was supposed to be the worst possible choice. 相似文献40.