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61.
目的探讨体内外基因转移F as配体(F as-ligand,F asL)对恶性人黑素瘤细胞凋亡的影响。方法用携带人F asL cDNA的缺陷型重组腺病毒(A d-F asL),在体外转导两株黑素瘤细胞,并使其表达;通过流式细胞仪、RT-PCR法进行F as/F asL表达检测,TUNEL法及荧光显微镜相关凋亡检测、分析。建立人黑素瘤裸鼠模型,并对其进行体内疗效观察及病理学检查。结果流式细胞仪和RT-PCR检测两株黑素瘤细胞表面均表达F as,不表达F asL,而A d-F asL转导的两株黑素瘤细胞均能表达F asL;A d-F asL能显著诱导两株黑素瘤细胞在体外凋亡或抑制其生长。体内疗效观察黑素瘤荷瘤鼠模型治疗组瘤重(0.48±0.16)g与对照组瘤重(1.02±0.19)g相比,差异有显著性(P<0.05)。肿瘤组织形态学检查,治疗组可见肿瘤细胞凋亡坏死区及炎性细胞浸润。结论F asL基因重组腺病毒在体内外均具有显著诱导人黑素瘤细胞凋亡的效果。 相似文献
62.
Peter Gode Göran Lindbergh Göran Sundholm 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(2):115-122
A new method to study permeation of gases in proton conducting membranes using a cylindrical microelectrode is presented. The focus of this work was to develop an in-situ method to study transport properties of hydrogen and oxygen close to real fuel cell operating conditions. The gas permeability is strongly affected by the change of water content in the membrane and it is therefore of advantage that, by using this method, measurements can be carried out over a wide range of relative humidities. The numerical method makes it possible to separate the diffusion coefficient and the concentration of dissolved gas in the membrane and also allows kinetic limitations to be taken into account. Chronoamperometric measurements on Nafion® 117 were successfully evaluated numerically. Experiments at temperatures of 25 and 60 °C with respect to oxygen permeation and at 60 °C for hydrogen permeation at relative humidities in the range 30–94% are presented. The reproducibility of data was excellent when measuring with different microelectrodes on the same membrane sample, but differed when measuring on different samples. In general, the permeability increases with increasing temperature and relative humidity. 相似文献
63.
目的 研究Ⅳ型胶原在膀胱癌中的表达及其临床意义。方法 应用免疫组化方法检测Ⅳ型胶原在65例膀胱癌及19例非肿瘤性膀胱组织中的表达,分析其与膀胱癌的病理分级、分期、复发、多发的关系。结果 Ⅳ型胶原表达与膀胱癌的病理分级、分期相关(P<0.01),而与肿瘤的复发、多发无明显相关(P>0.05),非肿瘤性膀胱组织未见Ⅳ型胶原染色。结论 Ⅳ型胶原的表达与膀胱癌浸润和转移相关,对膀胱癌的预后判断及治疗具有一定的意义。 相似文献
64.
作者分别用差速离心法及蔗糖梯度离心法制备胎盘微绒毛膜(PMM),用受体放射分析法研究了PMM的转铁蛋白受体(TfB),结果表明:两种方法制备的PMM均可用于受体分析,但差速离心法更为简便。测定60例产妇PMM的TfR,其数目为3.53±1.98×10~(12)个位点/mg膜蛋白,最大结合容量为6.33±4.21×10~(-12)mol/mg膜蛋白,Kd值为4.95±3.39×10~(-9)mol/L。受体结合反应体系最适实验条件为,膜蛋白浓度每管50μg,标记物浓度每管50 000cpm,孵育30分钟,B/F分离的聚乙二醇浓度为12%(W/V)。对TfR的特性研究表明:TfR与转铁蛋白的结合具有高度亲和力、高度特异性及可饱和性。 相似文献
65.
66.
67.
J. Mäurer A. Kendzia H. Gerlach D. Pappert J. Hierholzer K. J. Falke R. Felix 《Intensive care medicine》1998,24(11):1152-1156
Objective: To determine whether the quality of infiltrations in chest radiographs can accurately predict the histological extent of
fibrotic change in patients with acute respiratory distress syndrome (ARDS). Design: Retrospective clinical investigation. Setting: Intensive care unit (ICU) of a university teaching hospital. Patients and methods: Of 47 patients treated with extracorporeal membrane oxygenation (ECMO) for severe ARDS over a 5-year period, 23 patients
underwent open lung biopsy at thoracotomy for treatment, mostly of pneumothorax. Chest films obtained by portable chest roentgenography
preceding the operation were reviewed retrospectively and compared to the histomorphological results of the lung specimen.
Results: Chest radiographs displayed mixed alveolar-reticular opacification in 60.2 %, alveolar patterns in 22.9 % and reticular
opacities in 10.5 %. In 0.4 % there were no infiltrates, 6 % could not be evaluated because of insufficient quality. There
was no relevant difference between the right and left lungs. Subdividing patients into two groups according to the histological
results of either absent or mild (1) or severe (2) lung fibrosis, we found an alveolar haziness in 12.3 % in group 1 compared
with 28.2 % in group 2, while reticular characteristics were identified in 13 % and 11 %, respectively. Conclusions: The most common opacity in chest radiographs of patients with severe ARDS treated with ECMO is mixed alveolar-reticular
opacification. Severe lung fibrosis is not positively correlated with a reticular radiographic pattern. ECMO does not lead
to specific radiological changes in conventional radiograms, contrary to clinical findings that treatment with ECMO might
induce pleural or pulmonic haemorrhage, especially in the earlier days when systemic heparinization had to be used instead
of the heparin-coated tube-surfacing.
Received: 24 November 1997 Accepted: 20 July 1998 相似文献
68.
患者,女,32岁,因左(足 母)趾内侧疼痛8年,加重伴(足 母)趾肿胀1个月入院。入院前曾行血尿酸、抗O、RF未见异常,ESR28mm/L。入院查体:疼痛性跛行,左(足 母)趾跖趾关节周围红肿,有压痛,第一跖趾关节活动度检查:跖屈与背伸均为30°。X线示左(足 母)趾第一跖趾关节跖内侧可见多数散在的、大小相仿的高密度钙化影(图1)。入院诊断:左(足 母)趾跖趾关节滑膜性骨软骨瘤病。完善术前各项准备后,于2001年7月24日在连续硬膜外麻醉下行左(足 母)趾跖趾关节滑膜性骨软骨瘤切除术。 相似文献
69.
To evaluate the effect of interleukin-8 (IL8) on glomerular basement membrane (GBM) sulfated compounds and albuminuria, we
infused IL8 in 1% bovine serum albumin (BSA) for 5 days into the left renal artery of Holtzman male rats at the rate of 10
μl/h using an osmotic pump. Control rats received 1% BSA. A significant increase in urinary albumin/creatinine ratio was seen
on the last day of IL8 infusion (0.38±0.11, mean ± SEM) when compared with albumin/creatinine ratio prior to infusion (0.19±0.04,
P = 0.04). No significant differences in urinary albumin excretion prior to and after infusion of 1% BSA were observed. On
the last day of infusion, rats were injected with 35sulfate (1.0 mCi/200 g body weight) intraperitoneally and killed after 8 h. Glomeruli were isolated and GBM obtained. After
5 days of IL8 administration, there was a significant increase in 35sulfate uptake by GBM of the infused kidney (76±10 cpm/dry glomerular weight, mean ± SEM) compared with the uptake seen in
the contralateral kidney (53±9, P = 0.05). The in vivo infusion of IL8 increased the 35sulfate uptake by GBM and augmented the urinary albumin/creatinine ratio, suggesting that IL8 may induce albuminuria by altering
the metabolism of the GBM sulfated compounds. This hypothesis needs to be confirmed by studies on glomerular charge selectivity
and GBM anionic sites during the course of the infusion. Moreover, the persistence of the effect needs to be evaluated by
prolonging the infusion for more than 5 days.
Received June 3, 1996; received in revised form and accepted October 18, 1996 相似文献
70.