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排序方式: 共有7719条查询结果,搜索用时 430 毫秒
31.
H. Ono R. Akiyama Y. Sakamoto J. T. Pearson H. Tazawa 《Medical & biological engineering & computing》1997,35(4):431-435
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat.
A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure
the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an
electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG
measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet
is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system.
Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs,
indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of
the velocity of egg movements. 相似文献
32.
Nobuaki Miyazono M.D. Hiroki Inoue Akira Hori Ichiroh Kanetsuki Jurio Shimada Masayuki Nakajo 《Cardiovascular and interventional radiology》1994,17(1):36-37
We present a 44-year-old woman in whom a bronchialto-coronary artery communication via the conus branch was discovered after distal bronchial artery embolization with gelatin sponge for hemoptysis. If this bronchial-to-coronary artery anastomosis, not visible prior to embolization, had been inadvertently embolized, the patient could have developed a myocardial infarction. To reduce the likelihood of a serious complication, the possibility of this anastomosis should be kept in mind and angiography should be repeated before attempting proximal bronchial artery embolization. 相似文献
33.
头面部复杂动静脉畸形的栓塞治疗 总被引:2,自引:0,他引:2
目的 研究经导管栓塞技术在头面部动静脉畸形治疗中的应用。方法 3 0例头面部动静脉畸形患者共接受 40次栓塞治疗。其中使用国产TH胶栓塞者为 18例 2 0次 ,使用进口PVA微粒栓塞者为 12例 2 0次。结果 3 0例患者均成功实行瘤灶供血动脉栓塞术。所有患者栓塞术后临床症状明显改善 ,如瘤体缩小甚至消失 ,皮温降低 ,搏动感和血管杂音减弱或消失等。术后随访3~ 6个月 ,12例复发。全部病例均无严重并发症。结论 对于头面部动静脉畸形的患者来说 ,经导管栓塞术是一种较好的非手术治疗方法 ,在栓塞剂的选择方面 ,则以PVA微粒栓塞更为理想。 相似文献
34.
Martin Buehrer Klaas P Pruessmann Peter Boesiger Sebastian Kozerke 《Magnetic resonance in medicine》2007,57(6):1131-1139
Arrays with large numbers of independent coil elements are becoming increasingly available as they provide increased signal-to-noise ratios (SNRs) and improved parallel imaging performance. Processing of data from a large set of independent receive channels is, however, associated with an increased memory and computational load in reconstruction. This work addresses this problem by introducing coil array compression. The method allows one to reduce the number of datasets from independent channels by combining all or partial sets in the time domain prior to image reconstruction. It is demonstrated that array compression can be very effective depending on the size of the region of interest (ROI). Based on 2D in vivo data obtained with a 32-element phased-array coil in the heart, it is shown that the number of channels can be compressed to as few as four with only 0.3% SNR loss in an ROI encompassing the heart. With twofold parallel imaging, only a 2% loss in SNR occurred using the same compression factor. 相似文献
35.
We report a novel double wire technique for ipsilateral access of the external iliac/common femoral artery transition side-branches in a patient with active extravasation. The case is noteworthy in that asymptomatic extravasation was noted in both the inferior epigastric and deep circumflex iliac branches on femoral angiography prior to intraaortic balloon pump insertion following emergent diagnostic left heart cathetrization. We speculate the side branch injury was related to the J-wire and describe how this complication may be best treated by the ipsilateral technique reported herein. 相似文献
36.
Optimization of localized 19F magnetic resonance spectroscopy for the detection of fluorinated drugs in the human liver. 总被引:1,自引:0,他引:1
Dennis W J Klomp Hanneke W M Van Laarhoven Arno P M Kentgens Arend Heerschap 《Magnetic resonance in medicine》2003,50(2):303-308
Fluorine MR spectroscopy ((19)F MRS) is an indispensable tool for assessing the pharmacokinetics of fluorinated drugs. Since the metabolism of 5-fluorouracil (5FU), a frequently used cytotoxic drug, is expected to be different in normal liver and in tumor tissue, spatial localization is required for detection by MRS. In this study, three independent signal-to-noise ratio (SNR) optimizations were combined to enable chemical shift imaging (CSI) as a localization method in the detection of 5FU and its metabolites in tumor tissue. First, the hardware was optimized by using circularly polarized coils together with integrated preamplifiers. Second, the optimal pulse angle (Ernst angle) was determined on the basis of T(1) relaxation time measurements of 5FU. Finally, averaging of CSI phase-encoding steps was optimized by using the applied Hamming filter as a weighting function. The combination of these three methods enables the in vivo detection of 5FU and alpha-fluoro-beta-alanine (FBAL) by (19)F MRS, localized in three dimensions in tumor and liver tissue at a time resolution of 4 min at 1.5 Tesla. 相似文献
37.
Summary
The case of a 10-year-old boy with post-traumatic priapism after perineal trauma is presented. Interdisciplinary treatment
using angiography and selective catheter embolization for juvenile high-flow priapism is demonstrated. The literature and
the diagnostic possibilities resulting from color duplex sonography are discussed.
相似文献
38.
姜士炜 《中国医师进修杂志》2003,26(6):24-25
目的 探讨电解可脱式微弹簧圈 (GDC)栓塞治疗颅内动脉瘤的方法。方法 采用美国波士顿公司GDC栓塞治疗 1 7例患者中 1 8个颅内动脉瘤 ,其中 1 5例蛛网膜下腔出血 (SAH)发病者 ,术前Hunt和Hess分级 :Ⅰ~Ⅱ级1 0例 ;Ⅲ级 3例 ;Ⅳ级 2例。结果 1例死亡 ,3例轻度短期神经功能障碍 ,1 3例痊愈。结论 GDC栓塞治疗颅内动脉瘤较为理想 ,但还需随访观察 相似文献
39.
(胡国栋)(李小明)(黄志程)(胡道予)TheSignificanceofAnatomicalVariationsofHepaticArteryandMultipleArterialSuppliesinEmbolizationofLiverTumors¥HU... 相似文献
40.
眼球孤立性脉络膜血管瘤的HR-MRI表现 总被引:4,自引:0,他引:4
目的 探讨眼球孤立性脉络膜血管瘤的高分辨率磁共振 (HR MRI)影像学特征 ,进一步提高诊断水平。资料与方法 回顾性分析诊断明确的孤立性脉络膜血管瘤 16例共计 17个病灶的位置、数目、形态、大小、MRI信号、强化情况、有无合并视网膜脱离及有无视神经和眼外侵犯等。所有病例均行HR MRI及增强扫描 ,部分病例行脂肪抑制。结果 17个病灶中的 16个呈扁丘状位于眼球内壁的后极。 15个病灶厚度 <5mm ,平均厚度为2 .9mm。病灶边缘清晰 ,T1WI上呈轻度高信号者 16个 ,T2 WI上呈等信号者 15个 ,增强扫描显著强化者有 12个。 3例合并视网膜脱离 ,在T2 WI上多呈等信号 ,T1WI上呈轻度高信号者 ,均无强化。无视神经及眼外侵犯病例。结论 94 %孤立性脉络膜血管瘤的HR MRI表现具有特征性 ,表现为位于眼球内壁后极的较小、基底较宽、边缘清晰的扁丘状病灶。其T1WI信号高于玻璃体 ,T2 WI信号等于玻璃体 ,增强扫描瘤体显著强化。明确其HR MRI影像学特征有助于临床与恶性葡萄膜黑色素瘤相鉴别 ,避免不必要的眼球摘除 相似文献