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991.
目的 探讨终末期肝病模型(MELD)评分评估肝储备功能在原发性肝癌合并肝硬化脾功能亢进中确定手术适应证的应用价值.方法 对2001年1月至2007年1月间行肝癌切除联合脾切除(联合术)治疗的40例原发性肝癌合并肝硬化脾功能亢进患者的临床资料进行回顾性分析.通过MELD评分与Child-Pugh分级比较,结合临床资料及术后并发症分析,确定这一方法在评估肝储备功能中的作用.结果 同一Child-Pugh分级的患者MELD评分结果并不一致,在各级别间有交错现象.术后发生肝功能衰竭组(6例)的MELD评分均值为(24.6±6.6).未发生肝功能衰竭组(34例)的MELD评分均值为(16.3±8.5),差异有统计学意义(P<0.05).根据MELD评分分为A组16例(MELD评分<10),B组17例(MELD评分10-20),C组7例(MELD评分>20).A组术后肝功能衰竭发生率为0,B组为11.8%(2/17),C组为57.1%(4/7),差异有统计学意义(P<0.05).根据Child-Pugh分级分为Ⅰ级26例,Ⅱ级14例.Ⅰ级术后肝功能衰竭发生率为15.4%(4/26),Ⅱ级为14.3%(2/14),差异无统计学意义(P>0.05).结论 MELD评分能够较为客观地反映肝储备功能,对外科术式的选择、手术时机的确定有一定的参考作用. 相似文献
992.
医学图像序列压缩是远程医疗系统中的重要技术,而运动估计在视频序列压缩中起着关键作用。我们提出了一种改进的正方形-菱形搜索算法来实现医学图像序列的运动估计。这种改进的正方形-菱形算法减少了搜索点数。我们将其应用于小波域的医学图像序列的运动估计,并对数字减影血管造影图像序列(DSA)进行实验。结果表明,改进后的小波域正方形-菱形算法较其他算法精度高。 相似文献
993.
994.
Progressive multifokale Leukoenzephalopathie bei Wegener'scher Granulomatose unter Therapie mit Cyclosporin A 总被引:1,自引:0,他引:1
J. Ettinger W. Feiden G. Hübner M. Schreiner 《Journal of molecular medicine (Berlin, Germany)》1989,67(4):260-264
Summary A female patient with Wegener's granulomatosis developed severe bone marrow depression after two years treatment with cyclophosphamide. Corticosteroids alone could not sufficiently suppress disease activity, therefore additive therapy with Cyclosporin A was started. Four weeks later the patient developed a central nervous system disorder with affective disturbances and progressive somnolence. However, inspite of intensive diagnostic procedures, no definite diagnosis could be established. After another two months she died. Post-mortem-examination showed progressive multifocal leukoencephalopathy. An association between immunosuppressive therapy and reactivation of JC-Virus is suggested.
Abkürzungsverzeichnis PML Progressive multifokale Leukoenzephalopathie - WG Wegener'sche Granulomatose - CyA Cyclosporin A - (C)CT (Craniale)Computertomographie - NMR Nuclear Magnetic Resonance (Kernspintomographic) - ZNS Zentralnervensystem - AIDS Acquired Immuno-deficiency Syndrome 相似文献
Abkürzungsverzeichnis PML Progressive multifokale Leukoenzephalopathie - WG Wegener'sche Granulomatose - CyA Cyclosporin A - (C)CT (Craniale)Computertomographie - NMR Nuclear Magnetic Resonance (Kernspintomographic) - ZNS Zentralnervensystem - AIDS Acquired Immuno-deficiency Syndrome 相似文献
995.
Prof. Dr. C. -P. Sodomann G. Maerker-Alzer K. Havemann C. Dienst H. Schultz D. Mitrenga K. Schumacher G. A. Martini 《Journal of molecular medicine (Berlin, Germany)》1979,57(17):893-903
Summary It is a clinically and experimentally well supported working hypothesis that infection with hepatitis B virus may result in chronic active hepatitis in patients with suspected immune deficiencies. On this basis, a pilot study was performed in order to evaluate the effect of specific transfer factor (TF) in the treatment of HBs-Ag-positive chronic active hepatitis. From the leukocytes of 500 ml venous blood each of 40 volunteers that had completely recovered from acute virus hepatitis B within the last 6 months, a unique TF pool (40 units of TF) was prepared according to the method of Lawrence. Preexaminations indicated that this preparation was able to enhance cellular immune reactions in vitro. Thirteen patients with HBs-antigenemia and chronic active hepatitis (i.e., two liver biopsies within the last 6 or more months with the histological criteria of chronic aggressive hepatitis according to de Groote, elevated serum levels of bilirubin, alkaline phosphatase, transaminase activities, and/or -globulines) were randomized: Seven received s.c. injections of two units of TF each on days 1 and 15, the other six saline. Conversion of skin reactions to some ubiquitous antigens occurred in the TF group, but no significant and constant drop of HBs-Ag serum titers was observed. Although some of the biochemical parameters seemed to ameliorate in the TF group, the differences versus the control group did not prove to be significant within the limited number of patients under observation. The in vitro reactivity of patients' lymphocytes to HBs-Ag, tested by means of the3H-thymidine uptake, was never found enhanced after TF application. In the used doses, specific TF was not effective in the treatment of HBs-Ag-positive chronic active hepatitis; unfavorable side-effects were not observed. 相似文献
996.
M. Vandenbranden J.L. de Coen R. Jeener L. Kanarek J.M. Ruyschaert 《Molecular immunology》1981,18(7):621-631
Interactions between rabbit-γ-immunoglobulins and model membranes (lipid monalayers, planar lipid bilayers, liposomes) have been investigated. No significant interaction was observed with immunoglobulins. However, immunoglobulins dialysed first vs aqueous buffer having pH 2 or 3 and then dialysed against pH 7 buffer presumably adopt a new conformation which allows their bindings to model membranes. This binding is hydrophobic and the immunoglobulin region interacting with the lipid acyl chains is probably located in the heavy chain, as suggested by labelling in this region by a photosensitive probe previously incorporated into the lipid hydrophobic core. Cleavage at the hinge region by papain or pepsin, or heating above 38°C, induces the loss of the hydrophobic conformation responsible for hydrophobic bindings. The binding capacity of immunoglobulins heated above 38°C is restored after momentary dialysis at pH 2. The possible existence of two Ig isomers is discussed in relation to the mechanism of γ-immunoglobulin passage through the endoplasmic membrane and fixation into the plasma membrane. 相似文献
997.
A new method of detecting eye movements (EMs) during sleep is described. The method consists of an electromechanical measurement using micro-miniaturized silver cup electrodes. These electrodes, when placed on the eyelid, produce electro-oculographic (EOG) recordings similar to the usual electrical method. The eyelid method offers the advantage of a relatively “clean” recording showing only EMs and movement artifact, with no intermingling of EEG and EOG. Furthermore, the method is at least one and one half times as sensitive as the usual EOG technique. In addition to these two special advantages, it also offers the features of conventional methods, convenience of DC coupling, independence from signal converters, ease of analyzing EM directionality, and durability despite the small size of the electrodes. Fabrication of the electrodes, recording configurations, and simultaneous comparisons to both the usual EOG technique and to a strain gauge method are described. 相似文献
998.
P. Lehnert H. Stahlheber O. Roder M. Zoelch M. M. Forell E. Wünsch E. Jaeger H. L. Martens 《Journal of molecular medicine (Berlin, Germany)》1973,51(1):44-46
Zusammenfassung Die relative Wirksamkeit von synthetischem Secretin (Wünsch) und reinem natürlichen Secretin ohne Zusatz von Cysteinhydrochlorid (Mutt) sowie von reinem natürlichem Secretin mit Zusatz von Cysteinhydrochlorid (G.I.H. Research Unit) wurde am Parameter der Volumen-und Bicarbonatsekretion des Pankreas bei 10 narkotisierten Bastardhunden geprüft. Die relative Wirksamkeit von synthetischem Secretin liegt — bezogen auf Gewichtsbasis — bei 100% gegenüber natürlichem (Mutt) (Parameter: Volumen- und Bicarbonatsekretion). Die biologische Aktivität von synthetischem Secretin beträgt ungefähr 3,58 klin. E/µg (Parameter: Volumensekretion) bzw. 3,88 klin. E/µg (Parameter: Bicarbonatsekretion) gegenüber dem Secretin mit Zusatz von Cysteinhydrochlorid (G.I.H. Research Unit). Natürliches Secretin (Mutt) hat eine biologische Aktivität gegenüber dem Secretin mit Zusatz von Cysteinhydrochlorid (G.I.H. Research Unit) von annähernd 3,52 klin. E/µg (Parameter: Volumensekretion) bzw. 3,48 klin. E/µg (Parameter: Bicarbonatsekretion).Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
999.
当归注射液对脑血栓患者花生四烯酸代谢产物和氧自由基水平的影响 总被引:4,自引:0,他引:4
目的 :了解当归注射液改善脑循环治疗脑血栓的临床效果。方法 :对 46例脑血栓形成患者应用当归注射液进行治疗 ,对比分析其治疗前后血浆前列环素 (PGI2 )、血栓烷A2 (TXA2 )及自由基水平。结果 :脑血栓形成患者TXA2 、丙二醛 (MDA)明显升高 ,超氧化物岐化酶 (SOD)明显降低。当归注射液治疗后上述改变明显减轻或恢复至正常组水平。结论 :当归注射液能有效调节花生四烯酸代谢产物和氧自由基水平 ,对治疗脑血栓效果明显。 相似文献
1000.
Neurophysiological brain activity evoked by individual spoken words and pseudowords was recorded and the mismatch negativity (MMN), an automatic index of experience-dependent auditory memory traces, was calculated. Consistent with earlier reported results, the MMN response to word-final syllables was enhanced compared with that elicited by the same syllables placed in a pseudoword context. Here we now demonstrate that the enhancement of the MMN elicited by two individual words showed different scalp topographies. The early word-specific brain activity is consistent with the assumption that the memory traces activated by individual words are carried by large neuronal ensembles that differ in their distributions over the cortex. Current source estimates localized the between-word differences in the right hemisphere and in parieto-occipital left-hemispheric areas. The differential brain responses to individual words appeared as early as ∼100 ms after the recognition points of the words, suggesting that their specific memory traces become active almost immediately after the information in the acoustic input is sufficient for word identification. 相似文献