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141.
Yamada Shinichi Takahashi Shun Malchow Berend Papazova Irina Stöcklein Sophia Ertl-Wagner Birgit Papazov Boris Kumpf Ulrike Wobrock Thomas Keller-Varady Katriona Hasan Alkomiet Falkai Peter Wagner Elias Raabe Florian J. Keeser Daniel 《European archives of psychiatry and clinical neuroscience》2022,272(6):957-969
European Archives of Psychiatry and Clinical Neuroscience - Significant evidence links white matter (WM) microstructural abnormalities to cognitive impairment in schizophrenia (SZ), but the... 相似文献
142.
MR imaging of primary malignant lymphoma of the pancreas 总被引:2,自引:0,他引:2
Pancreatic lymphoma is rare and is usually found as a large pancreatic mass. We report the case of a small 2-cm pancreatic lymphoma in a 54-year-old woman that had its histological origin in the pancreatic parenchyma. The mass showed homogeneously high signal-intensity on T2-weighted images and low signal-intensity on T1-weighted images. The infiltrative nature and hypovascularity in early-phase dynamic contrast study without encasement of arteries and veins were well demonstrated by MR imaging and were consistent with malignant lymphoma. 相似文献
143.
OBJECTIVES: The aim of this study is to evaluate the usefulness of gastroesophageal reflux (GER) scintigraphy using the knee-chest (KC) position for the diagnosis of gastroesophageal reflux disease (GERD). METHODS: The study subjects were 37 patients with GERD and 8 healthy volunteers (control group). Endoscopically observed esophageal mucosal breaks were evaluated with the Los Angeles classification. For GER scintigraphy, the subjects ingested liquid yogurt labeled with 99mTc-diethylene triamine pentaacetic acid (99mTc-DTPA) and water. Imaging was performed in the supine and KC position, and GER was graded as 1-4 according to the extent of GER assessed by scintigraphy. RESULTS: GER scintigraphy revealed no reflux in the control group (specificity: 100%). In the supine position, gastroesophageal reflux was observed in 49% of the patients with GERD, compared to 76% in the KC position. 21 of 23 (91%) patients with erosive esophagitis were shown to have GER with scintigraphy. GER scintigraphy revealed severe reflux (grade 3 or 4) (83%, 10/12) in the patients who had severe mucosal breaks (LA grade C or D). GER scintigraphy detected grade 1 or 2 reflux in 7 of the 14 patients who were endoscopically negative. There was a correlation between the endoscopically determined severity of mucosa and the reflux grade which was determined with GER scintigraphy. CONCLUSION: GER scintigraphy can detect gastroesophageal reflux with a high sensitivity in the KC position and might be a useful method in the screening and assessment of the severity of this disease. This method would be useful for the diagnosis of GERD in endoscopically negative patients. 相似文献
144.
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
145.
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
146.
Fan Jiang Qi Miao Bin Xu Shinichi Tashiro Manabu Tanaka Sanbao Lin Chenglei Fan Shujun Chen 《Materials》2022,15(9)
A novel bypass coupling variable polarity plasma arc was proposed to achieve the accurate adjusting of heat and mass transfer in the welding and additive manufacturing of aluminum alloy. However, the physical characteristics and decoupled transfer behavior remain unclear, restricting its application and development. A three-dimensional model of the bypass coupling variable polarity plasma arc was built based on Kirchhoff’s law, the main arc and the bypass arc are coupled by an electromagnetic field. The model of current attachment on the tungsten electrode surface is included for simulating different heating processes of the EP and EN phases in the coupling arc. The distribution of temperature field, flow field, and current density of the bypass coupling variable polarity plasma arc was studied by the three-dimensional numerical model. The heat input on the base metal under different current conditions is quantified. To verify the model, the arc voltages are compared and the results in simulation and experiment agree with each other well. The results show that the radius of the bypass coupling arc with or without bypass current action on the base metal is different, and the flow vector of the bypass coupling arc plasma with bypass current is larger than the arc without bypass current. By comparing the heat transfer on the electrodes’ boundary under different current conditions, it is found that increasing the bypass current results in the rise in heat input on the base metal. Therefore, it is concluded that using bypass current is unable to completely decouple the wire melting and the heat input of the base metal. The decoupled degree of heat transfer is one of the important factors for accurate control in the manufacturing process with this coupling arc. 相似文献
147.
Thanh Binh Nguyen Hiroyuki Ida Mai Shimamura Daishi Kitazawa Shinichi Akao Hideki Yoshida Yoshihiro H Inoue Masamitsu Yamaguchi 《American journal of cancer research》2014,4(4):325-336
In man, COX (cytochrome c oxidase) deficiency is reported to be related to mutation of the SCO2 (synthesis of cytochrome c oxidase 2) gene, which encodes one of the copper-donor chaperones involved in the assembly of mitochondrial cytochrome c oxidase. Such COX deficiency due to the genetic condition leads to heart disease and the Leigh syndrome and is frequently fatal in childhood. Synthesis of cytochrome c oxidase X (SCOX) is a Drosophila orthologue of human SCO2. Here, we generated SCOX-knockdown flies and the full length SCOX transgenic flies to investigate the in vivo roles of SCOX. Our results demonstrated knockdown of SCOX gene in all cells and tissues to be associated with lethality at larval or pupal stages and this correlated with a decrease in ATP level. In contrast, the full length SCOX transgenic flies showed a longer lifespan than wild type flies and control flies carrying Act5C-GAL4 alone and this correlated with an increase in ATP level. Finally, when cultured on paraquat-added medium, full length SCOX transgenic flies also exhibited an elongated lifespan. Therefore, we hypothesized that SCOX plays an important role in ATP production and consumption, which helps to prevent production of mitochondrial reactive oxygen species and/or impairment of mitochondrial activity under oxidative stress. 相似文献
148.
Satoshi Okayama M.D. Yoko Dote M.D. Yukiji Takeda M.D. Shiro Uemura M.D. Shinichi Fujimoto M.D. Ph.D. Yoshihiko Saito M.D. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(1):E13-E15
A 63‐year‐old man was referred to our hospital because of a cardiac tumor. Transthoracic echocardiography revealed a rough, mobile tumor in the dilated right atrium, and transesophageal echocardiography showed that the tumor consisted of small, botryoidal masses. Catheter‐based biopsy carried a high risk of embolism. Therefore, we used F‐18‐fluorodeoxyglucose positron emission tomography (FDG‐PET), which revealed an abnormal accumulation in the right cervical lymph nodes, as well as in the heart. We safely performed biopsy of the lymph nodes and diagnosed the patient with primary cardiac lymphoma. We concluded that echocardiography and FDG‐PET are useful for selecting an appropriate biopsy site in primary cardiac lymphoma. 相似文献
149.
150.