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971.
Wakamatsu T Saito T Hayashi J Takeichi T Kitamoto K Aizawa K 《Medical molecular morphology》2005,38(4):225-232
Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the
long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional
injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg,
was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength
664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised
and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the
balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated
arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in
the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was
repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit
restenosis after vascular intervention.
An erratum to this article is available at . 相似文献
972.
抑郁症患者威斯康星卡片分类测验和连续操作测验的初步研究 总被引:22,自引:3,他引:22
目的 :通过与精神分裂症患者和正常对照的比较 ,探讨抑郁症患者的执行功能和注意功能。方法 :采用威斯康星卡片分类测验 (WCST)、连续操作测验 (CPT) ,对 66例精神分裂症患者、 42例抑郁症患者和 5 0名对照者的执行功能和注意功能进行评估。结果 :两组患者WCST中的总测验次数、持续错误数和随机错误数均明显多于对照组 (P <0 0 1) ;其中精神分裂症组WCST的三项成绩明显差于抑郁症组 (P <0 0 1) ;无干扰刺激时 ,精神分裂症组的认对数明显差于抑郁症组和对照组 (P <0 0 1) ,而抑郁症组与对照组之间的差异无显著性 (P >0 0 5 ) ;有干扰刺激时 ,精神分裂症组与对照组的差异有显著性 (P <0 0 1) ,抑郁症组与其它两组的差异均无显著性 (P >0 0 5 )。结论 :抑郁症组有执行功能障碍 ,介于精神分裂症组和对照组之间 ;在抑郁症组中没有发现有明显的注意障碍。 相似文献
973.
The effects of cycle racing on pulmonary diffusion capacity and left ventricular systolic function 总被引:1,自引:0,他引:1
Stickland MK Petersen SR Haykowsky MJ Taylor DA Jones RL 《Respiratory physiology & neurobiology》2003,138(2-3):291-299
The purpose of this study was to examine the effects of a 20 km cycle race (TT) on left ventricular (LV) systolic and pulmonary function in 12 endurance cyclists. Spirometry, single-breath diffusion capacity (DLCO) with partitioning of membrane (DM) and capillary blood volume (Vc) components and 2-D echocardiograms were performed before and after the TT. During the TT mean oxygen consumption was 3.79 +/- 0.5 L x min(-1) (83 +/- 5.5% of VO2max) and mean blood lactate was 8.4 +/- 2.4 mM. Following the TT, spirometry values were unchanged, however, DLCO and DM were significantly (P<0.05) reduced. LV systolic function was increased (P<0.05) immediately after exercise, while end-diastolic area was decreased (P<0.05) at all points during recovery. The reduction in DM was correlated with LV systolic function following the TT. This relationship suggests a cardiovascular contribution to pulmonary diffusion impairment following exercise. 相似文献
974.
目的探讨阴道镜下高频电灼术联合重组人干扰素α-2a治疗尖锐湿疣(CA)的效果。方法将165例CA分为3组,A组应用阴道镜下高频电灼术联合重组人干扰素α-2a;B组单纯采用阴道镜下高频电灼治疗;C组应用NS-FII型多功能光谱治疗仪联合肌注重组人干扰素α-2a。结果治疗后3-6个月A、B、C组复发率分别为0%、4.4%、65.4%:半年后人乳头瘤病毒(HPV)转阴率分别为93.5%、85.4%、43.8%,A组明显优于B组,B组明显优于C组,3组比较差异有统计学意义(P〈0.01)。结论阴道镜下高频电灼术联合重组人干扰素α-2a治疗CA可明显降低CA复发率和提高HPV转阴率。 相似文献
975.
荷EL4肿瘤小鼠模型的建立及美法仑抑瘤作用免疫机制的探讨 总被引:4,自引:6,他引:4
目的:建立荷小鼠淋巴瘤EL4的野生型C57BL/6小鼠及其裸鼠模型,探讨美法仑(melphalan)抑瘤作用的免疫机制。方法:给正常野生型C57BL/6小鼠皮下接种小鼠淋巴瘤EL4细胞,建立荷EL4肿瘤的小鼠模型。于野生型C57BL/6小鼠皮下接种瘤细胞后12d,经腹腔给荷瘤小鼠单次注射不同剂量的美法仑,找出美法仑可发挥最大的抑瘤作用,并能致使肿瘤消退、不再复发的最小使用剂量。然后再给野生型C57BL/6小鼠及其裸鼠(遗传背景相同)皮下同时接种小鼠淋巴瘤EL4细胞建立两种荷瘤小鼠模型。同样于接种瘤细胞后12d,经腹腔给两种荷瘤小鼠模型均注射可使野生型C57BL/6小鼠肿瘤消退、不再复发的最低剂量的美法仑,以正常野生型C57BL/6小鼠为对照,观察在T淋巴细胞缺陷的裸鼠体内美法仑的抑瘤作用。结果:注射7.5mg/kg美法仑治疗后,免疫功能正常的野生型C57BL/6荷瘤小鼠的肿瘤消退;而荷瘤C57BL/6裸鼠的肿瘤仍继续生长。结论:单一剂量的美法仑对荷淋巴瘤EL4小鼠具有明显的治疗作用,其作用的发挥需要T淋巴细胞的参与,可能与T细胞的杀伤作用有关。 相似文献
976.
The modulation transfer function for an elliptical tomographic scan is derived. Its imaging characteristics are compared with
those of linear and circular scans
Zusammenfassung Die Modulationsaustauschfunktion einer elliptischen tomographischen Abastung wird abgeleitet. Ihre Abbildungsmerkmale werden mit denen von linearen und runden Abtastungen verglichen.
Sommaire La fonction de transfert de modulation d'un balayage tomographique elliptique est dérivée dans cet article. Ses caratéristiques d'image sont comparées avec celles des balayages circulaires et linéaires.相似文献
977.
Petersen TR Gülland S Bettelli E Kuchroo V Palmer E Bäckström BT 《International immunology》2004,16(7):889-894
A key question yet to be resolved concerns the structure and function relationship of the TCR complex. How does antigen recognition by the TCR-alphabeta chains result in the activation of distinct signal transduction pathways by the CD3-gammadeltaepsilon/zeta complex? To investigate which part of the TCR-beta chain is involved in TCR signaling, we exchanged different domains of the constant regions of the TCR-beta chain with the corresponding TCR-gamma chain domains. We show here that hybridoma cells expressing a chimeric TCR-beta chain (betaIII) containing intracellular and transmembrane TCR-gamma amino acids, together with a wild-type TCR-alpha (alphawt) chain, were 10 times more sensitive to antigenic stimulation compared to cells expressing TCR-alphawt/betawt chains. This super-signaling phenotype of the betaIII chain was observed in two different TCRs. One specific for an alloantigen (I-A(bm12)) and one for an autoantigen (I-A(b)/MOG(35-55)). We found that this chimeric alphawt/betaIII TCR had normal association with CD3-gammadeltaepsilon and zeta chains. To investigate the effect of the chimeric betaIII chain in transgenic T cells, we made MOG(35-55)-specific TCR transgenic mice expressing either the alphawt/betawt or chimeric alphawt/betaIII TCR. Similar to what was observed in hybridoma cells, transgenic alphawt/betaIII T cells showed a super-signaling phenotype upon antigenic stimulation. Further studies may help us understand the effect of increased TCR signaling on autoimmunity and may lead to the identification of signaling molecules that can be targeted to stop the progression of autoimmune disorders such as multiple sclerosis. 相似文献
978.
Takeshi Komoda MD Thorsten Drews MD Hans B. Lehmkuhl MD Roland Hetzer MD PhD 《Journal of artificial organs》2006,9(1):29-33
The Eurotransplant (ET) allocation algorithm, newly implemented in 2000, gives priority for heart transplantation (HTx) to
patients with high urgency (HU) status, but now this status is rescinded upon ventricular assist device (VAD) implantation
and only regained if severe complications occur during mechanical circulatory support (MCS). We studied the effects of this
change on the patients in our institute who were waiting for HTx with MCS. The median duration of MCS until HTx in adult patients
gradually increased from 3.1 months in 1994, reaching a peak of 16.7 months in 2000, and then gradually decreased to 6.0 months
in 2003. Among the patients with VAD implantation as a bridge to HTx, two patients were on MCS for more than 1 year (the longest
duration of MCS being 1.6 years) at the end of 1999, and this figure increased to nine patients and a maximum MCS duration
of 3.7 years at the end of 2003. These data imply that the patients in whom a complication occurred in the early phase of
MCS and who had overcome this complication underwent HTx early with HU status, and those who were stable during MCS waited
a long time for HTx. Furthermore, the number of patients in the latter group is increasing. The new allocation algorithm imposes
on patients with MCS waiting for HTx who are relatively young and free from complications and serious coexisting disease,
very long-term MCS without an end to VAD bridging, which is almost equivalent to destination therapy.
Part of this paper was presented at the 42nd JSAO Conference (Tokyo, October 5–7, 2004) 相似文献
979.
Rostoker Rymer Bagnard Petit-Phar Griuncelli Pilatte 《Clinical and experimental immunology》1998,114(3):468-476
Following recent experimental data suggesting an aggravating effect of circulating proinflammatory cytokines on the histological lesions of IgAN, we studied changes in serum proinflammatory cytokines and their soluble receptors and antagonists in patients treated with polyvalent immunoglobulins (15 with severe nephropathy who had indicators of poor prognosis: heavy proteinuria, hypertension, altered renal function and Lee's histological grade III or IV; and 14 with moderate forms of IgAN who had permanent albuminuria > 300 mg/day and < 2000 mg/day, Lee's histological grade II and a glomerular filtration rate > 70 ml/min) in comparison with healthy controls (n = 20) and patients with non-IgA nephritides (n = 50). These were measured by means of specific immunometric assays before and after 9 months of immunoglobulin therapy. Total tumour necrosis factor (TNF) serum and IL-6 levels were elevated in IgAN patients before therapy, relative to controls, and normalized after immunoglobulin therapy. Levels of soluble TNF receptor of type I (sR55) and type II (sR75) increased on immunoglobulin therapy. TNF index α-55,75 used to assess biologically available TNF-α (ratio of total TNF-α divided by levels of soluble TNF receptors sR55 and sR75) was elevated before therapy and was below healthy control values after 9 months of immunoglobulin administration. Levels of serum IL-1 receptor antagonist were low prior to immunoglobulin administration in patients with severe forms of IgAN, and normalized on therapy. Serum interferon-gamma was unmodified. The histological activity index correlated with serum total TNF-α, TNF index α-55,75 and serum IL-6 levels, whereas proteinuria correlated with serum total TNF-α and TNF index α-55,75 but not with serum IL-6. These data suggest that the overproduction of proinflammatory cytokine is unbalanced by their natural antagonists in IgAN and Henoch–Schönlein syndrome. This process may play a role in the progression of the disease and be one of the targets of immunoglobulin therapy. 相似文献
980.
本文采用放免法测定实验性犬心肌梗塞和溶栓后再闭塞时血浆中GMP-140、TXB2、6-K-PGF1α的含量变化,并探讨其与心肌梗塞溶栓后再闭塞的关系。结果表明,在血栓形成时血浆中TXA2稳定代谢产物TXB2水平显著升高(p〈0.05),在溶栓后再闭塞率高(87.5%)的非治疗组(B组)。在溶栓后4小时至溶栓后3天期间呈进行性升高(p〈0.01),而在再 埘经低(16.7%)的API0134治疗组( 相似文献