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101.
T. J. Vogl S. Steiner B. Schnell A. Gerbes C. McMahon C. Wilimzig J. Lissner 《European radiology》1992,2(4):310-316
Twenty-nine patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI was performed using T1- and T2-weighted spin-echo sequences as well as fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). in patients with hepatitis, MRI could be used in guiding liver biopsies as inflammatory changes were clearly delineated. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. On the other hand MRI was more helpful in differentiating fatty changes and neoplasm. In liver cirrhosis, fibrotic changes were most clearly demonstrated by MRI. In patients suffering from hemochromatosis MRI offers advantages over CT and ultrasound in the diagnosis and follow up due to the paramagnetic properties of iron, resulting in a reduction in signal intensity. In patients with Wilson's disease a characteristic pattern of parenchymal changes was seen. Administration of Gd- DTPA contributes additional information about perfusion conditions in the liver parenchyma, however this information was not of diagnostic relevance in the cases we studied.
Correspondence to: T.J. Vogl 相似文献
102.
103.
Most clinical procedures using the laser are based on thermal laser-tissue interactions. The treatment often consists of inducing damage of given degree and extent by heating the tissue. The aim of this study was to develop a model called HELIOS. The ability of HELIOS to predict thermal coagulation was evaluated by comparison with in vivo experimental results. Conversion of laser light in tissue was studied using the beam-broadening model. Temperature was described by the heat conduction equation solved using the finite difference method. The tissue dena-turation was modeled by the Henriques equation leading to the determination of the damage coefficient ω. For a given set of laser and tissue parameters, HELIOS makes a graphic representation of coagulation necrosis and temperature evolution in tissue. HELIOS was validated by experimental studies in vivo on rat liver using a CW Nd:YAG laser, a CO2 laser, and an argon laser. For given sets of laser parameters, temperature measurements were performed using an infrared camera. Histological examinations were carried out on samples to quantify the depth of coagulation necrosis. Experimental data obtained in vivo were compared with those calculated using HELIOS and similar sets of parameters. The difference between the predicted temperature evolution on tissue surface and that measured by the infrared camera was < 5°C in all cases. The difference between the predicted coagulation necrosis depth and the corresponding experimental one was < 10%. In conclusion, HELIOS allows good prediction of tissue temperature and coagulation necrosis. © 1994 Wiley-Liss, inc. 相似文献
104.
用聚焦层析结合DEAE-Sephadex A-50离子交换层析,从正常人肝浸液中分离得两个精氨酸酶同工酶组分.经聚丙烯酰胺凝胶电泳(PAGE)鉴定从聚焦层析得到的第一峰同工酶组分为一条蛋白带,第二峰具有精氨酸酶活性的蛋白组分的主要蛋白带也极明显。各蛋白质成分向阴极电泳的前后顺序与从聚焦层析洗脱的先后次序一致。两型同工酶的比活力分别约为2050U/mg及790U/mg。用SDS-PAGE检测两型同工酶均由两种亚基组成,且分子量近似。 相似文献
105.
目的:探讨大鼠肝脏低温保存及常温缺血再灌注过程中,不同保存液中嘌呤核苷磷酸酶(PNP)活性的变化.方法:将大鼠肝脏在3种不同保存液中低温保存不同时限后,用37℃Krebs-Henseleit液连续循环灌注90min,分别于不同灌注时间检测灌洗液中PNP活性的变化.结果:经过8 h的低温保存,再灌注90min后,HTK保存的肝脏中PNP明显高于UW和Celsior;经过16 h的低温保存后,再灌注60min前,HTK保存的肝脏中PNP明显高于UW和Celsior;60min后HTK和Celsior保存的肝脏中PNP明显高于UW;经过24 h的低温保存后,再灌注15min后,HTK保存的肝脏中PNP明显高于Celsior,而Celsior又明显高于UW.结论:随着低温保存和再灌注时间的延长,大鼠肝脏中PNP逐渐增高且UW液的保存效果明显优于HTK和Celsior 相似文献
106.
肝纤维化组织中MMP1、TIMP1的表达及其临床意义 总被引:2,自引:1,他引:1
目的 :检测肝纤维化组织中基质金属蛋白酶 1 (MMP1 )、基质金属蛋白酶组织抑制因子 1 (TIMP1 )的表达 ,为肝纤维化的诊治提供重要的分子生物学指标。 方法 :采用链霉菌抗生物蛋白 -过氧化酶联接法 (S- P法 )检测70例肝纤维化组织中 MMP1 、TIMP1 的表达。结果:(1) TIMP1 蛋白阳性表达随肝纤维化程度的加重而增强 ,并且呈正相关关系 (r=0 .92 74 ,P <0 .0 1)。 (2 ) MMP1 蛋白阳性表达随肝纤维化程度的加重无明显变化 ,无相关关系(r =0 .2 181,P >0 .0 5 )。 结论:TIMP1 与肝纤维化的发生、发展密切相关 ,随纤维化发生、发展阳性表达增强。从分子水平对肝纤维化、肝硬化病变进行评估 ,为早期诊治肝纤维化和判断预后提供依据。 相似文献
107.
Objective This study was conducted to evaluate the effects of postoperative glutamine and growth hormone on the nutritional status,immune function,and inflammatory responses of patients undergo-ing portal hypertension surgery.Methods This study was designed as a prospective,randomized and con-trolled clinical trial.Forty-two patients undergoing portal hypertension surgery were randomly divided into 2 groups:experimental group (receiving an immune enhancing parenteral nutrition by adding glutamine and re-combinant human growth hormone,n = 22),and control group (receiving an isocaloric and isonitrogenons standard parenteral nutrition,n = 20).Parenteral nutrition providing 125 kJ · kg-1·d-1 was initiated 3 days after surgery in both groups and last for 7 days.Blood samples were obtained on day 0th,3rd,and 10th.Host nutritional status was evaluated by measuring levels of prealbumin and transferrin,immunity was evalu-ated by measuring levels of CD4,CD8,CD4/CD8,IgG,IgM and IgA,and the inflanunatory responses was determined by assessing IL-2,TNF-α and C-reactive protein (CRP) levels.Results Ten days after opera-tion,among patients receiving an immune enhancing parenteral nutrition,the serum prealbumin was (193.84±39.78)mg/L,transferrin was (2.07±0.51)mg/L,CD4 was (33.7±5.5)%,CD4/CD8 was (1.17±0.32),IgG was (13.94±1.09)g/L and IL-2 was (368.12±59.25) pg/mL.They were signifi-cantly higher than those of the control group (P < 0.05).The TNF-α concentrations was (321.12±81.42)pg/mL and CRP was (32.2±15.2)mg/mL which were significantly lower than those of the control group (P < 0.05).Conclusion Postoperative administration of immune enhancing parentearl nutrition in patients undergoing portal hypertension surgery can improve nutritional status and immune function,and modulate inflammatory response is also better than standard one. 相似文献
108.
目的研究低浓度5-Fu 24-小时持续化疗和高浓度5-Fu短时间化疗对BEL-7402肝癌细胞株的细胞周期的影响:方法用低浓度(1000.0μg/L)的5.Fu对BEL-7402肝癌细胞株进行持续24小时的培养(A组),用高浓度(50000.0μg/L)的5-Fu对BEL-1 7402肝癌细胞株进行2小时培养(B组),在培养后的不同时间点用流式细胞技术检测细胞周期的变化。结果A组结果显示:0h、4h、8h、12h、16h、20h和24h的S期细胞的百分数分别为25.23%、32.35%、39.28%、41.05%、46.02%、47.00%及47.14%。B组结果显示:0h、4h、8h、12h、16h、20h和24h的S期细胞的百分数分别为24.68%、68.43%、46.67%、43.67%、35.42%、33.22%及32.96%。结论5-Fu引起的S期细胞周期阻滞不但和浓度相关,也和作用时间相关。低浓度(1000.0μg/L)的5-Fu持续化疗较高浓度(50000.0μg/L)的5-Fu短时间(2小时)化疗更容易引起BEL-7402肝癌细胞株S期阻滞。 相似文献
109.
孔海莉 《浙江中医药大学学报》2006,30(4):372-372,374
[目的]探讨脂肪肝有效治疗方法。[方法]采用HD-91-2型肝病治疗仪、中药穴位透入、推按运经治疗脂肪肝24例。[结果]总有效率为91.67%。[结论]HD-91-2型肝病治疗仪作为一非药物治疗脂肪肝又一途径,是值得临床推广。 相似文献
110.
肝癌患者血清P-选择素测定及临床意义 总被引:2,自引:0,他引:2
目的:研究肝癌患血清P-selection(P-sel)在肝癌复发和转移中的作用。方法:采用ELISA法分别测定原发性肝癌患和对照组血清P-选择素的含量,同时测定AFP含量。结果:肝癌患P-sel含量显高于正常人,且与AFP含量呈线性正相关,术后2周浓度降低;P-sel含量以Ⅰ、Ⅲ和Ⅳ期肝癌患显高于Ⅰ期患;且大肝癌患显高于小肝癌患,有癌栓组、有肝内转移组明显高于无癌栓组和无转移组。结论:P-选择素测定在原发性肝癌的诊断和检测术后复发方面有重要价值,联合检测AFP和sP-sel可提高诊断敏感性。 相似文献