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排序方式: 共有835条查询结果,搜索用时 93 毫秒
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Yoshinori Igarashi Naoki Okano Ken Ito Takahiko Mimura Kazumasa Miki 《Digestive endoscopy》2007,19(Z1):S109-S114
A 69‐year‐old man was admitted to Toho University Omori Medical Center complaining of icterus. Abdominal computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography were suspicious of cholangioma of inferior bile duct. Peroral cholangioscopy using narrow band imaging (NBI) was performed and it was possible to diagnose the mucosal spread lesions of cholangioma. Histological findings reflected the endoscopic findings. Mucosal spread lesions of cholangiocarcinoma were successfully diagnosed using the CHF‐B260 for NBI. 相似文献
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Case report Leptomeningeal involvement in diffuse intrinsic brain stem gliomas is rarely diagnosed clinically and in majority of the instances diagnosed only on postmortem examination. We report two cases of diffuse pontine glioma diagnosed clinicoradiologically and treated with conventional radiotherapy.Observations On follow-up, both patients showed clinical features suggestive of meningeal spread although imaging for pontine tumor showed stable disease. Leptomeningeal disease in the spine was confirmed on imaging and in one case by cerebrospinal fluid examination also. During the follow-up of patients with pontine glioma, the possibility of leptomeningeal involvement must be borne in mind. 相似文献
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Dirk Mayer Wolfgang Dreher Dieter Leibfritz Daniel M Spielman 《Magnetic resonance in medicine》2007,57(5):967-971
A numerical simulation tool was developed to calculate the echo amplitudes of J-coupled resonances within a series of radiofrequency (RF) refocused echoes. The signal modulation due to J-coupling in rapid acquisition with relaxation enhancement (RARE) is suppressed only when the inverse of the pulse interval (tau) is large compared to both the chemical shift (CS) difference (Deltadelta) of the coupled spins and the coupling constant. In contrast, the echo amplitudes in ultrafast low-flip-angle RARE (U-FLARE) oscillate around a quasi-steady-state value that is greater than zero (neglecting relaxation and diffusion) even when Deltadelta > 1/tau. The flip-angle distribution over the measured slice caused by the use of Gaussian-shape slice-selective refocusing pulses further reduces the echo oscillations. When the pulse interval falls short of the fast pulse rate regime, spectroscopic U-FLARE provides an improved spatial impulse response in the phase-encoding (PE) direction compared to spectroscopic RARE. 相似文献
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彭现美 《中国初级卫生保健》2007,21(11):67-70
通过艾滋病的流行和传播与其他发展目标的相互影响,论证遏制并扭转艾滋病蔓延的紧迫性,同时采取多途径确保千年发展目标的最终实现。 相似文献
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There is a close similarity between the unconventional virus-induced ovine scrapie and human Creutzfeldt-Jakob disease. Since infection might be transmitted orally, the ovine production of an endemically scrapie-infected farm was studied. About 80% of the annual production are sold (50% as butcher-meat, 30% as breeding animals), and scrapie appears in 20% of the sheep kept on the farm. Was the same proportion of butcher-meat animals scrapie-infected? Since the scrapie agent has been detected in “clinically normal” lambs, the same problem occurs with breeding-sheep and “apparently healthy” animals: are they carriers of the pathogenic agent? Are they responsible for the spread of the ovine disease and/or of the human disease? 相似文献
8.
E. V. Bagshaw M. H. Evans 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1976,25(4):391-400
Summary Tungsten stimulating microelectrodes have been tested in monopolar, bipolar and concentric configurations for the extent to which unwanted current spread occurred. Current spread from monopolar electrodes in close conformity with the predictions of the inverse square law, both in vitro and in vivo. The bipolar and concentric configurations, tested only in vitro, had current-spread characteristics which did not follow the inverse square law so closely. The bipolar configuration gave little reduction in spread, compared with a monopolar electrode, but the concentric configuration did reduce the extent of stimulus spread. The extent of spread depends greatly upon a number of experimental variables, including the dimensions of the microelectrode tip. For studies requiring precise localization, with low stimulus currents, it is advisable to determine the inverse square law constant for each experimental situation. For more generalized stimulation purposes within the mammalian C.N.S., employing monopolar microelectrodes of moderate tip size, brief pulses of 10 A can be expected to stimulate myelinated axons within about 0.15 mm of the tip, and 100 A will stimulate within a radius of about 0.5 mm.The work was all done while E.V.B. was on Industrial Training leave from the North-East Polytechnic, Romford Road, London E. 15 相似文献
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目的 探索基于街道的新型冠状病毒肺炎(简称新冠肺炎)疫情社区传播风险评估方法,提升政府的公共卫生管理水平。方法 采用综合评分法,整合深圳报告的新冠肺炎确诊病例的关键信息,建立新冠肺炎社区传播风险快速评估方法。结果 截至2020年2月29日,深圳市累计报告新冠肺炎确诊病例417例,其中感染来源为湖北武汉地区有224例(53.7%),湖北省其他地区80例(19.2%),其他省市38例(9.1%),深圳市内感染75例(18.0%)。选取“14 d内街道的新冠肺炎病例数(X1)”、“14 d内新冠肺炎病例数的明确感染来源占比(X2)”及“14 d内街道内发生新冠肺炎的社区占比(X3)”作为新冠肺炎社区传播风险快速评估方法的关键指标,建立评价方程Y=0.4X1+0.5X2+0.1X3。将前期已报告的392例具有明确现住址的新冠肺炎确诊病例回代计算,高风险街道15个(20.2%),中风险街道25个(33.8%),低风险街道共34个(50.0%)。福田区、南山区、龙华区、龙岗区的高、中风险街道的比例均超过60%。结论 新冠肺炎社区传播风险快速评估方法简易有效,有助于疫情的精准防控。 相似文献
10.
陈健 《同济大学学报(医学版)》2000,21(10):124-127
以比较美学的方法,有选择地比较和阐述了世界各地装饰纹样的起源背景、各自特点以及它们之间的相互影响。认为各民族、各地区的装饰艺术存在着相通中有不同、不同中有相通的关系,为现代艺术设计者带来了继承和变化的资源,同时也为体味和享受异域装饰美提供了理解的通道。 相似文献