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31.
Fritz Schick Hermann Einsele Renate Kost Stephan Duda Wulf-Ingo Jung Otto Lutz Claus D. Claussen 《Journal of magnetic resonance imaging : JMRI》1994,4(1):71-78
Magnetic resonance (MR) studies were performed in 14 patients as early as possible (21–110 days) after bone marrow transplantation (BMT). MR characteristics of lumbar vertebral bone marrow were studied with T1-weighted spin-echo imaging, water- and fatselective imaging with a frequency-selective excitation technique, and point-resolved spatially localized proton spectroscopy. Signals from water and fat protons and their T1 and T2 values were analyzed. Water proton signal intensity correlated well with cellularity within bone marrow, as determined with parallel iliac crest biopsies. The fraction of signal from water in red bone marrow of patients with allogeneic transplants from siblings (four cases) was significantly higher than in four patients with autologous transplants. The latter showed very low cellularity in the period of about 4 weeks after BMT because of the cytotoxic pretreatment of the bone marrow. The MR results in six patients with allogeneic transplants from unrelated donors ranged widely, depending on the complications after BMT. Analysis of data obtained with the different techniques showed that water- and fat-selective MR imaging and spectroscopic methods are useful for noninvasive monitoring of hematopoietic reconstitution after BMT. 相似文献
32.
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
33.
34.
Porcine models have been used extensively for skin flap research because of the established similarity between the cutaneous
blood supply of the swine and humans. The Yucatan minipig provides an excellent model for researching the properties of random
cutaneous flaps, offering several advantages over other breeds of swine. In this study, a total of 67 random cutaneous dorsal
flank flaps measuring 4 × 14 cm were raised on nine Yucatan minipigs. The mean survival length (10.03 ± 1.60 cm) of the nondelayed
flaps was greater than others reported in the literature. The well-defined plane between the subcutaneous tissue and the panniculus
carnosus facilitated flap elevation consistently above the level of the panniculus carnosus thereby ensuring the creation
of a true random cutaneous flap. Furthermore, the hairless nature of the skin, particularly beneficial in studying chemical
peels, permits easy visualization and monitoring of any external skin changes. These advantages make the Yucatan minipig a
more desirable alternative to other breeds of swine for use in skin flap research. 相似文献
35.
蛛网膜下腔注入小剂量吗啡术后镇痛与PCEA比较研究 总被引:1,自引:0,他引:1
目的 :探讨蛛网膜下腔小剂量吗啡术后镇痛的临床效果并与 PCEA相比较。方法 :将 ASA I~II级 6 0例妇科择期手术患者 ,随机分为两组 ,每组 30例。实验组采用腰麻 ,局麻药为 0 .75 %布比卡因 10~ 15 m g加入吗啡 0 .5 mg。对照组采用腰麻复合 PCEA,局麻药 0 .75 %布比卡因 10~ 15 mg,术后 PCEA。术后镇痛效果以视觉模拟评分 (VAS)、Ram say镇静评分、BCS舒适评分、成功率、不良反应并结合医疗费用比进行评价。结果 :VAS评分两组在 4、8、36 h时段无显著性差异 (P>0 .0 5 ) ;实验组在 12、2 4 h镇痛效果优于对照组 ,4 8、5 4 h对照组优于实验组。 BCS舒适评分、Ram say镇静评分两组间无显著性差异。结论 :蛛网膜下腔注入小剂量的吗啡用于术后镇痛的效果并不亚于 PCEA,如采用医疗费用与治疗效果比 ,更优于后者 相似文献
36.
The role of endoscopic extraperitoneal herniorrhaphy (EEPH) in the management of giant scrotal hernias has not been well
defined, and the technical details relating to operations on such hernias have not been described. We present our experience
with 17 patients undergoing repair of giant scrotal hernias. Foley catheter bladder decompression was routinely employed.
The Retzius space was developed early in the procedure and hernia sac contents were reduced in all cases. The inferior epigastric
vessels were likewise divided in all patients. The average operative time was 76 min and all patients were discharged home
the same day. There have been no recurrences on follow-up. There was no mortality, and morbidity was limited to seroma formation
in two patients. We conclude that with certain technical modifications, EEPH can be safely employed for the treatment of giant
scrotal hernias.
Received: 7 May 1996/Accepted: 12 July 1996 相似文献
37.
Summary
The compartment syndrome (cs) is characterized by an increased tissue pressure in a limited space. Pathophysiologically, it
is a multifactorial disease that is potentially induced by an initial trauma and develops according to the existence of cofactors.
Cofactors are, for instance, the circulation of the patient and the initial treatment of the impending cs. In particular,
the microcirculation is altered with endothelial destruction, development of a capillary leak, protein loss from intravasal
space and the development of an interstitial and intracellular third space. An impaired drainage of the lymphatic and venous
system causes a venous infarction. An arterial infarction results if the tissue pressure exceeds the arteriolar pressure.
An accompanying ischemia reperfusion mechanism increases the trauma load. In disadvantageous cases, the patients are in danger
of developing a multi-organ deficiency syndrome (MODS) by an uncontrolled inflammatory reaction, by intravasal volume loss
and by a myonephropathic systemic reaction. Clinically, the patients suffer a disproportionate amount of pain, followed by
neurological signs. Especially in noncompliant patients, tissue pressure measurement is useful. Resuscitation of the circulation
as well as splitting of casts is important. In case of a manifest cs, dermatofasciotomy has to be performed as an emergency
operation. Even if cs is diagnosed early and fasciotomy is carried out early, the development of sequellae cannot be avoided
in every single case.
相似文献
38.
目的:报告了因汽车安全气囊造成的眼外伤及化学性烧伤。希望引起眼科同仁的高度重视.方法:4例病人均是进口高档小卧车,在发生碰撞时因汽车安全气囊高速膨胀打开及气囊破裂所致的眼损伤及化学烧伤.分析了汽车型号及种类,事故发生时的速度,眼损伤的类型和视力情况.结果:第一例病人为碱性化学性角膜炎伴虹膜根部离断及瞳孔括约肌破裂而造成瞳孔扩大;第二例病人为近视镜片致角巩膜板层撕裂伤;第三例病人为广泛角膜擦伤伴前房出血;第四例病人为视网膜水肿出血伴后极部脉络膜裂伤.结论:安全气囊能保护生命降低致伤率,但因气囊的冲击力量引起的机械损伤和气囊中强碱性气体导致的化学烧伤更要引起国内眼科医生的注意. 相似文献
39.
目的探索硬膜外导管置入脓腔引流对口腔颌面部脓肿的疗效。方法采用既往常规切开引流的患者作为对照组。治疗组为经面部皮肤用18号硬膜外穿刺针穿刺入脓腔,置入硬膜外导管,在口内做切口旋转引流条,或经颌下作小切口,置入负压引流管,经硬膜外导管滴注抗生素盐水冲洗脓腔,比较两者拔出引流物的时间,并行U检验。结果治疗组与对照组比较,差异具有统计学意义(P<0.01)。结论经硬膜外穿刺针置管引流术,具有创伤小、炎症消失快、有效缩短病程、愈后不留瘢痕的特点。 相似文献
40.
本文分析了20例有明确蛛网膜下腔出血病史的正常颅压脑积水患者的临床表现,其中有智能、步态障碍、尿失禁三联征典型表现者占11例(55%),有其中二个症状者4例。CT是诊断脑积水的首选检查。本文还结合文献对正常颅压脑积水的发生发展,与之有关的因素及临床表现进行讨论。 相似文献