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101.
D. Nolte S. Pickelmann S. Swaid F. H?lzle und K.-D. Wolff 《Mund-, Kiefer- und Gesichtschirurgie》2003,7(1):31-35
Zusammenfassung
Fragestellung. Ziel der vorliegenden Untersuchung war, die Effekte der Sauerstoff tragenden freien H?moglobinl?sung (Diaspirin-crosslinked-H?moglobin,
DCLHb) auf die kapillare Perfusion sowie die Oxygenation im quergestreiften Hautmuskelgewebe nach kritischer Isch?miezeit
und nachfolgender Reperfusion zu analysieren.
Material und Methode. Die kapillare Gewebeperfusion wurde anhand der funktionellen Kapillardichte im Hautmuskel des syrischen Goldhamsters quantitativ
vor der Induktion einer 4-stündigen Isch?mie sowie nach 0,5 h, 2 h und 24 h Reperfusion mittels intravitaler Fluoreszenzmikroskopie
erfasst (n=8 pro Versuchsgruppe). In separaten Tieren wurde nach demselben Versuchsansatz mit der Mehrdrahtoberfl?chenelektrode (MDO,
Eschweiler, Kiel) die Gewebeoxygenation gemessen (n=8 pro Versuchsgruppe). Die Tiere der Testgruppe (n=8) erhielten 15 min vor der Reperfusion eine Kurzinfusion von 5 ml/kg KG DCLHb (Diaspirin-crosslinked-H?moglobin, 10 g/dl,
Baxter, IL, USA). Die Kontrolltiere (n=8) erhielten ?quivalente Dosen einer isotonen Kochsalzl?sung (Braun, Melsungen).
Ergebnisse. Die funktionelle Kapillardichte als Ma? für die L?nge von erythrozytenperfundierten Kapillaren pro Beobachtungsfeld war bei
den Kontrolltieren in der Reperfusionsphase dramatisch vermindert, w?hrend bei den mit DCLHb behandelten Tieren signifikant
h?here Werte nachweisbar waren (p<0,05). Diese Beobachtung spiegelte sich in einer vollst?ndigen Erholung des Gewebe-pO2 bei den Behandlungstieren wider, was in Kontrolltieren nicht erreicht wurde.
Schlussfolgerungen. Die Ergebnisse dieser Studie zeigen, dass die Sauerstoff tragende L?sung DCLHb nach kritischer Isch?mie und Reperfusion die
nutritive Perfusion und Gewebeoxygenation gegenüber kristalloiden L?sungen verbessert. Die Anwendung derartiger L?sungen scheint
unter den klinischen Bedingungen einer kritischen Isch?mie daher als viel versprechender adjuvanter therapeutischer Ansatz.
Electronic Publication 相似文献
102.
目的 探讨自制苏芪合剂对Ⅲ~Ⅳ级IgA肾病患者的疗效及患者T细胞功能的改善.方法 28例Ⅲ~Ⅳ级IgA肾病患者随机分为两组,对照组:醋酸泼尼松-日1mg,kg,隔日晨起顿服,盐酸苯那普利-日10mg;治疗组:在上述用药的基础上加用自制苏芪合剂.8周后,观察患者缓解率、T细胞功能及不良反应.结果 治疗组患者在缓解率、T细胞功能改善等方面优于对照组,且因糖皮质激素的使用而出现的不良反应少于对照组.结论 苏芪合剂联合治疗Ⅲ~Ⅳ级IgA肾病疗效显著并能有效改善T细胞功能. 相似文献
103.
E. Zambricki T. Zal P. Yachi A. Shigeoka J. Sprent N. Gascoigne D. McKay 《American journal of transplantation》2006,6(11):2572-2579
T cells contact allogeneic antigen presenting cells (APCs) and assemble, at their contact interface, a molecular platform called the immunological synapse. Synapse-based molecules provide directional signals for the T cell--either positive signals, resulting in T-cell activation, or negative signals causing T-cell inactivation or anergy. To better understand the molecular basis of in vivo T-cell anergy we analyzed the contacts made between in vivo anergized T cells and APCs, and determined which signaling molecules were included or excluded from their immunological synapses. Anergy was induced in TCR transgenic mice by the intravenous injection of semiallogeneic donor spleen cells. T cells from anergized mice were mixed with APCs, the T-cell/APC synapses imaged using deconvolution microscopy, and their molecular compositions were determined. T cells from anergic mice formed unstable immunological synapses in vitro with allogeneic APCs and failed to recruit the signaling proteins necessary to initiate T-cell activation. These findings suggest that T-cell anergy induced by exposure to semiallogeneic donor cells is associated with defects in the earliest events of T-cell activation, immunological synapse formation and recruitment of TCR-mediated signaling proteins. 相似文献
104.
A. Datta R. David S. Glennie D. Scott E. Cernuda-Morollon R. I. Lechler A. J. Ridley F. M. Marelli-Berg 《American journal of transplantation》2006,6(12):2871-2883
The best-characterized mechanism of the action of immunosuppressive drugs is to prevent T-cell clonal expansion, thus containing the magnitude of the ensuing immune response. As T-cell recruitment to the inflammatory site is another key step in the development of T-cell-mediated inflammation, we analyzed and compared the effects of two commonly used immunosuppressants, cyclosporin A (CsA) and the rapamycin-related compound SDZ-RAD, on the motility of human CD4+ T cells. We show that CsA, but not SDZ-RAD, inhibits T-cell transendothelial migration in vitro. CsA selectively impaired chemokine-induced T-cell chemotaxis while integrin-mediated migration was unaffected. The inhibition of T-cell chemotaxis correlated with reduced AKT/PKB but not ERK activation following exposure to the chemokine CXCL-12/SDF-1. In addition, CsA, but not SDZ-RAD, prevents some T-cell receptor-mediated effects on T-cell motility. Finally, we show that CsA, but not SDZ-RAD inhibits tissue infiltration by T cells in vivo. Our data suggest a prominent antiinflammatory role for CsA in T-cell-mediated tissue damage, by inhibiting T-cell trafficking into tissues in addition to containing clonal expansion. 相似文献
105.
支原体肺炎肺外损伤患儿T细胞亚群、IFNγ、TNFα的变化及意义 总被引:1,自引:0,他引:1
目的 探讨支原体肺炎肺外损伤患儿细胞免疫、细胞因子状况和胸腺肽的治疗效果。方法 采用流式细胞仪和酶标仪检测31例支原体肺炎肺外损伤组患儿急性期、恢复期血中CD3CD4、CD8、CD4/CD8干扰素γ(IFNγ)、肿瘤坏死因子α(TNFα水平,并与支原体肺炎组比较。结果 ①急性期支原体肺炎肺外损伤组和支原体肺炎组比较,CD3、CD4显著降低(P〈0.05),TNFα显著升高(P〈0.01),CD8、IFNγ无统计学意义(P〉0.05);②支原体肺炎肺外损伤组急性期和4周后比较,CD3、CD4、IFNγ升高(P〈0.05),TNFα显著降低(P〈0.01),CD8无变化。用胸腺肽治疗患者以上指标变化更明显。结论 支原体肺炎肺外损伤患儿细胞免疫功能低于支原体肺炎患儿;细胞因子中TNFα早期升高,而IFNγ不明显;恢复期TNFα下降,而IFNγ升高明显。用胸腺肽治疗能缩短病程。 相似文献
106.
Because of the lack of organs for heart transplantations, left ventricular assist devices (LVADs) have become more and more important during the last few years. They are used for both bridging the time until transplantation as well as destination therapy for patients who are not able or willing to undergo a heart transplantation. Forensic and clinical pathologists will increasingly be confronted with fatalities of patients with LVADs. Beside natural causes of death and typical unavoidable complications, technical problems and user errors must be resolved. Under certain circumstances a suicidal or homicidal manner of death by manipulation of the device also has to be considered. 相似文献
107.
Gregg Hadley 《American journal of transplantation》2004,4(7):1026-1032
Infiltration of CD8(+)TCRalphabeta(+) T-effector populations (CD8 effectors) into graft epithelial compartments has long been recognized as a key lesion in progression of clinical renal allograft rejection. While the afferent phase of allograft immunity is increasingly well-defined, the efferent pathways by which donor-reactive CD8-effector populations access and ultimately destroy the graft renal tubules (rejection per se) have received remarkably little attention. This is an important gap in our knowledge of transplantation immunology, because epithelial compartments comprise the functional elements of most commonly transplanted organs including not only kidney, but also liver, lung, pancreas, and intestine. Furthermore, there is increasing evidence that attack of graft epithelial elements by CD8-effector populations not only causes short-term graft dysfunction but is also a major contributor to development of chronic allograft nephropathy and late graft loss, which now represent the salient clinical problems. Recent studies of the T-cell integrin, alpha(E)beta(7) (CD103), have provided insight into the mechanisms that promote interaction of CD8 effectors with graft epithelial compartments. The purpose of this communication is to review the known properties of the CD103 molecule and its postulated role in the efferent phase of renal allograft rejection. 相似文献
108.
目的设计和实现基于通用激光扫描仪的胶片剂量测量和验证系统。方法采用胶片饱和冲洗、非线性光学校正、多分辨率阈值滤波、离散傅里叶逆变换图像复原等方法,消除了普通扫描仪用于胶片剂量学定量处理中的各种伪影、噪声和畸变;采用过响应系数校正方法消除测量胶片对低能散射光子的过响应,改善了胶片剂量测量的准确性;采用γ结合NAT指标的方法对放疗计划进行二维定量验证,给出可视化图形表达和具有定量数据的验证结果。结果和三维水箱系统、VeriSoft胶片测量系统相比较,研制系统对放疗剂量的测量结果在±2%内符合一致,对IMRT放疗计划的定量验证结果在±3%内符合一致。结论该系统能够实现对放疗剂量的高精度测量和对适形调强放疗计划剂量的可靠验证。 相似文献
109.
目的 探讨CyclinD1,P16在胶质瘤复发前后表达改变及其意义。方法 采用免疫组织化学LsABC法对 4 5例复发胶质瘤瘤组织、瘤旁脑组织和 10例正常脑组织CyclinD1,P16蛋白表达进行检测 ,统计分析CyclinD1,P16表达水平与胶质瘤分级、肿瘤复发的关系。结果 正常脑组织 ,瘤旁脑组织和胶质瘤组织CyclinD1表达依次升高 ,而P16的表达依次下降 ;肿瘤复发CyclinD1表达增强 ,P16的表达减弱。结论 CyclinD1与P16的表达与胶质瘤恶性进程和复发密切相关。 相似文献
110.
Oral administration of an edible-mushroom-derived protein inhibits the development of food-allergic reactions in mice 总被引:5,自引:0,他引:5
K.-Y. Hsieh C.-I. Hsu† J.-Y. Lin† C.-C. Tsai‡ R.-H. Lin§ 《Clinical and experimental allergy》2003,33(11):1595-1602
BACKGROUND: Food allergy is a common disease without effective treatment. Since strict elimination of food allergens may be difficult, strategies for effective intervention are urgently needed. OBJECTIVE: The aim was to investigate the prophylactic use of orally administrated FIP-fve, an immunomodulatory protein isolated from the edible mushroom Flammulina velutipes, in a murine model of food allergy. METHODS: BALB/c mice were immunized twice intraperitoneally with ovalbumin (OVA), at an interval of 2 weeks. Before and during each period of immunization, FIP-fve (200 microg per mouse) or phosphate-buffered saline was given orally every other day with a total of five doses. Then OVA-specific antibodies and cytokine profiles were determined. Subsequently, the mice were orally challenged with OVA. Symptoms of anaphylaxis, levels of plasma histamine, and histology of intestines were examined. RESULTS: Mice receiving oral FIP-fve treatment during sensitization to OVA had an impaired OVA-specific IgE response with a Th1-predominant cytokine profile. These mice were protected from systemic anaphylaxis-like symptoms induced by subsequent oral challenge with OVA. CONCLUSION: Oral administration of FIP-fve has a Th1-skewing effect on the development of the allergen-specific immune response, and may serve the purpose of immunoprophylaxis for food allergy and other allergic diseases. 相似文献