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Pike G. B. 《The Italian Journal of Neurological Sciences》1997,18(6):359-365
While conventional magnetic resonance imaging (MRI) measures signal primarily from the hydrogen nuclei of water, magnetization transfer (MT) MRI indirectly detects macromolecular associated hydrogen nuclei via their magnetic interaction with the observable water. In the normal adult CNS, white matter exhibits the largest MT effect due to the macromolecular content of the highly structured and lipid rich myelin. Pathologies which alter the structural integrity and the relative macromolecular-water composition, such as multiple sclerosis (MS), therefore show abnormal MT. Conventional MRI, which has a high MS lesion detection sensitivity but poor specificity in terms of differentiating the pathological state of a plaque, can thus be supplemented by MT to provide more specific information on the extent of demyelination and axonal loss. In this paper we review the basic concepts of MT imaging and its role in MS lesion characterization.Financial support was provided by the Medical Research Council of Canada, Fonds de la Recherche en Santé du Québec, and the Killam Foundation. 相似文献
14.
微量沙眼衣原体组织培养法的建立及临床应用 总被引:8,自引:0,他引:8
建立了微量沙眼衣原体组织培养法,并应用于不同人群的生殖道标本的沙眼衣原体培养。结果生殖道沙眼衣原体培养的阳性率:男性尿道炎患者147%(9/61);正常孕妇33%(7/210);急性和亚急性盆腔炎女性患者67%(7/104);性病门诊患者182%(49/269)。由于96孔培养板及倒置荧光显微镜的应用,微量培养法试剂用量少、过程简化;自制的抗沙眼衣原体单克隆抗体大大降低了培养后的染色成本,适用于大宗标本。 相似文献
15.
W. Gubisch 《European journal of plastic surgery》1993,16(3):125-129
Summary Traumatic defects of the auricle are quite common. The eventual success of the repair is considerably influenced by the initial treatment. The different parts of the auricle require different approaches. This paper presents our methods for repairing damage to the cartilaginous frame using autologous ear cartilage grafts, and local flaps from the mastoid region to cover soft tissue defects. 相似文献
16.
Ultraviolet Laser-Induced Fluorescence Spectroscopy Diagnosis of Human Stomach Malignant Tissues 总被引:2,自引:0,他引:2
To evaluate the potential of laser-induced autofluorescence spectroscopy for the detection of premalignant lesions of human
stomach, fluorescence properties of stomach tissues have been investigated in vitro and in vivo. A specially made optical
fibre probe and the multichannel fluorescence collection system have been used successfully in our research.
Paper received 26 June 1997; accepted in revised form 31 October 1997. 相似文献
17.
组织工程化肌腱研究进展 总被引:17,自引:2,他引:15
对组织工程化肌腱领域中目前研究的主要成果进行综述,着重阐述了肌腱细胞外基质替代物、肌腱细胞生物学性质及肌腱细胞与细胞外基质材料复合研究中的主要问题。认为,研制适于肌腱细胞生长、粘附和发挥功能的细胞外基质材料;建立生长、增殖可调控的肌腱细胞系;在模拟体内力学条件下,进行肌腱细胞三维培养,将是研究具有特定修复功能的组织工程化肌腱的重要问题。 相似文献
18.
Dynamic Mechanical Conditioning of Collagen-Gel Blood Vessel Constructs Induces Remodeling In Vitro 总被引:11,自引:0,他引:11
Dynamic mechanical conditioning is investigated as a means of improving the mechanical properties of tissue-engineered blood vessel constructs composed of living cells embedded in a collagen-gel scaffold. This approach attempts to elicit a unique response from the embedded cells so as to reorganize their surrounding matrix, thus improving the overall mechanical stability of the constructs. Mechanical conditioning, in the form of cyclic strain, was applied to the tubular constructs at a frequency of 1 Hz for 4 and 8 days. The response to conditioning thus evinced involved increased contraction and mechanical strength, as compared to statically cultured controls. Significant increases in ultimate stress and material modulus were seen over an 8 day culture period. Accompanying morphological changes showed increased circumferential orientation in response to the cyclic stimulus. We conclude that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization. This concept, in conjunction with a proper biochemical environment, could present a better model for engineering vascular constructs. © 2000 Biomedical Engineering Society.
PAC00: 8719Rr, 8714Ee, 8718-h, 8768+z 相似文献
19.
Akihiro Umezawa Taketo Yamada Yuuto Ogawa Shigeru Kuramochi Yonosuke Watanabe 《Pathology international》1990,40(9):693-698
An autopsy case of acute megakaryocytic leukemia (AMKL) is presented. The bone marrow was hypercellular with proliferation of three lineages, especially megakaryocytes. Immunohistochemical examination revealed many platelet glycoprotein IIb/IIIa (GP IIb/IIIa)- positive blast cells in bone marrow. The proportion of the blasts was 26.4% by tissue hemogram. GP IIb/IIIa-positive blasts and megakaryoblasts were deposited massively in lymph nodes. lmmunohistochemistry against GP IIb/IIIa and tissue hemograms by paraffin section are needed to diagnose AMKL by postmortem examination, since the identification of ultra-structural platelet peroxidase in autopsy materials is difficult. 相似文献
20.
胶原基真皮再生支架的微结构控制 总被引:6,自引:0,他引:6
综述了影响胶原基真皮再生支架微结构的各种因素及其控制方法。胶原基真皮支架的生物活性和修复创面的能力受到诸如除胶原外的其它主要材料 (第二组分 )、支架的孔径和孔隙率、支架厚度、生物活性因子以及交联度等多方面因素的综合影响。从材料学、生物学和医学的角度综合地应用物理、化学和生物学的手段探索各种影响因素的控制方法是组织工程皮肤研究的重点。 相似文献