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81.
Bronchial hyperresponsiveness (BHR) and damage of the epithelium, as well as eosinophilia in the airway wall, induced by trimellitic anhydride (TMA) in sensitized brown Norway rats were studied. Rats were challenged once or seven times with aerosol of TMA conjugated to rat serum albumin (TMA-RSA) 3 weeks after intradermal TMA sensitization. Airway responsiveness (-log PC300 of acetylcholine i.v.) was measured 24 h after allergen challenge. Epithelial lesion and eosinophil infiltration in the airway walls were quantified under light microscopy, and TMA-specific IgE and IgG in serum were evaluated with ELISA. High levels of TMA-specific IgE and IgG were found in all rats in the sensitized groups compared to nonsensitized groups ( P < 0.001). Repeated allergen challenges of 0.03% TMA-RSA for 7 consecutive days enhanced the level of TMA-specific IgG, compared to single challenge ( P < 0.05). Single allergen challenge of 0.3% TMA-RSA had a nonsignificant tendency to produce BHR in sensitized rats compared to nonsensitized rats ( P =0.06). However, repeated allergen challenges (0.003% and 0.03% TMA-RSA for 7 consecutive days) produced significant BHR in sensitized rats ( P < 0.05). Furthermore, repeated low-dose (0.003%) TMA-RSA challenge produced more BHR than a 10 times higher single dose (0.03%) ( P < 0.05). Slight damage of the airway epithelium was seen in sensitized and repeat-challenged groups. However, bronchial eosinophilia was found in the sensitized and single-challenged groups, but not in nonsensitized nonchallenged, and sensitized repeat-challenged groups ( P < 0.005). We conclude that the brown Norway rat can be sensitized with TMA, and that repeated low-dose allergen challenges produce slight epithelial damage and BHR which is independent of ongoing eosinophilia in the airway wall.  相似文献   
82.
郑健梁  彭莹 《眼科学报》1997,13(4):170-172
目的:提供一种简单可行,易于掌握的体外培养人晶体上皮细胞的方法。方法:用无齿显微镊子将晶体囊膜分离出来,剪碎后直接移至细胞培养瓶中培养,当细胞长出融合后,用胰蛋白酶消化传代。结果:接种培养4天后,可见晶体上皮细胞开始长出,并以贴壁方式生长。结论:用此方法体外培养人晶体上皮细胞,具有简单、快捷、成功率高的优点。眼科学报1997;13:170—172。  相似文献   
83.
We report the first case of a unilateral microcysticMeesmann‘s epithelial dystrophy, observed in the left cornea of a 43-year-old patient. The diagnosis was verified histologically by the unilateral occurrence of a ’peculiar substance‘ within epithelial cysts and within the cytoplasm of the corneal epithelial cells. In an attempt to resolve thepatient‘s frequent corneal erosions, we performed an autologous stem cell transplantation from the non-involved right eye. The results are, so far, satisfactory. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
84.
We have previously established a cell damage model, with damage induced by either acid or pepsin treatment for 30 min, involving a rat gastric epithelial cell line (RGM1). In the present study, pretreatment of cells with epidermal growth factor (EGF; 0.1–10ng/mL) or sucralfate (0.1–3 mg/mL) for 4 h prevented such cell damage in a concentration-dependent manner. Protection of cells by these drugs was not affected by pretreatment with indomethacin (10−5 mol/L) for 4 h. Removal of Na, but not Ca2+, from the acidified medium totally abolished the inhibitory effect of EGF, but not that of sucralfate. Genistein (a tyrosine kinase inhibitor) apparently reduced the inhibitory effect of EGF. DNA synthesis by RGM1 cells did not increase when cells were incubated with EGF for 4 h. We conclude that both EGF and sucralfate protect RGM1 cells from acid- and pepsin-induced damage and that the mechanism of protection by EGF against acid-induced damage seems to be via activation of Na+/H+ exchangers.  相似文献   
85.
荆芥连翘汤对促进皮肤溃疡愈合的影响   总被引:4,自引:0,他引:4  
目的 观察荆芥连翘汤对小鼠皮肤溃疡的治疗作用。方法 建立小鼠皮肤创伤和烫伤两种皮肤溃疡模型.比较荆芥连翘汤以及rhEGF的用药组和自身对照组小鼠皮肤溃疡面积,用昆微镜观察溃疡面炎症细胞浸润情况。结果 和自身对照组相比,荆芥连翘汤可明显缩小小鼠皮肤溃疡面积(P〈0.001),同时炎症细胞浸润显著减少(P〈0.001);荆芥连翘汤用药组疗效显著优于rhEGF用药组。结论 荆芥连翘汤可明显促进小鼠皮肤溃疡的愈合。  相似文献   
86.
Abstract: To check the efficiency of intraperitoneal chemotherapy of ovarian carcinomas, 15 patients were treated with instillations of mitoxantrone or cisplatinum. An implantable catheter system was used to access the abdominal cavity. Local therapy proved to be without any effect when large tumor masses were treated. Patients with small tumor residues after surgery did not benefit either, partly because of extraperitoneal progress of the disease. Patients without evidence of disease proved to be stable. Side effects of the therapy were usually mild compared with those of systemic chemotherapy. Access to the peritoneal cavity with the implantable catheter proved to be safe and reliable.  相似文献   
87.
目的:研究重组杆状病毒(baculovinus)载体介导β—半乳糖苷酶基因(LacZ)对体外培养虹膜色素上皮(IPE)细胞的转染和表达情况。方法:将质粒pCMV—β中的CMV—LacZ表达盒插入杆状病毒表达栽体pFast BacI的Eco RI/Hind Ⅲ位点,构建重组质粒pBac—β,并利用Bac—to—Bac表达系统在Sf9细胞中产生出重组杆状病毒BV—β。将MOI为200的BV—β感染经酶消化加显微法分离培养的IPE细胞,24h后进行X-gal染色。在显微镜下观察IPE中LacZ表达阳性的情况,记录阳性细胞所占的百分比。结果:限制性酶切分析及测序结果表明,我们已成功构建表达质粒pBac—β及重组杆状病毒BV—β。X-gal染色证实杆状病毒介导LacZ在细胞中的表达呈蓝色,弥漫于整个胞浆。感染后24h时表达阳性率达85%。结论:重组杆状病毒可有效介导报告基因在体外培养的IPE细胞中表达,为利用杆状病毒构建可供移植的基因工程化虹膜色素上皮细胞提供了实验依据。  相似文献   
88.
BACKGROUND: Activation of urinary complement proteins in situ by proximal tubular epithelial cells (PTEC) may contribute to the mediation of tubulointerstitial injury in patients with significant proteinuria. However, the mechanism involved is unclear, and the role of changes in urinary pH and in the concentrations of urea or ammonia requires further clarification. METHODS: The protein fraction of urine samples from nine patients with proteinuria >1.5 g/day was purified. A cell ELISA involving cultured HK-2 PTEC was used to investigate the capacity of urinary protein to promote the deposition of both C3 and C9 on the cell surface. The effect of variations in pH (5.5-8.0) and in the concentration of urea and ammonia was also examined. C3 was purified and used to further investigate the mechanism of complement deposition. RESULTS: Urine samples from the majority of patients induced deposition of C3 and C9 on the surface of HK-2 cells via the alternative pathway. This process was maximal at acidic pH values. Preincubation of urinary complement or serum with urea or ammonia inhibited C3 deposition. Purified C3 incubated with HK-2 cells showed no evidence of activation in the absence of other complement components. CONCLUSIONS: These data suggest that bicarbonate protects against complement-mediated damage in the lumen by increasing the local pH, rather than by inhibiting the generation of ammonia. PTEC appear to activate complement through provision of a 'protected site' on their surface, rather than by the activation of C3 by convertase-like protease(s).  相似文献   
89.
大鼠小肠上皮细胞的体外原代培养   总被引:11,自引:0,他引:11  
目的:探讨大鼠小肠上皮细胞原代培养的原理与方法以及培养过程中常见的问题和克服办法。方法:取生后1周SD大鼠的小肠上皮细胞,经分离纯化后进行原代培养。结果与结论:胶原酶Ⅺ型和中性蛋白酶Ⅰ型配合使用,可以分离到形态完整、容易贴壁生长的小肠绒毛细胞团。进一步利用离心技术纯化得到95%以上的小肠上皮细胞。结果显示,常规体外培养的肠上皮细胞是否增殖分化最终决定于用酶消化后的结构完整性,如果用0.25%胰酶消化,则细胞受损程度较大,不易贴壁生长。  相似文献   
90.
卵巢癌肠道转移64例临床分析   总被引:2,自引:0,他引:2  
目的回顾性分析卵巢癌肠道转移瘤的临床特点,评价手术切除的可行性及其与预后的关系。方法64例肠道转移卵巢癌术前全面评估肠道受累程度。采用肿瘤细胞减灭术并行盆腔淋巴结清扫和腹主动脉旁淋巴结切除或/及活检术。肠道手术包括肿瘤剥除术或/及肠修补术、肠切除吻合术和结肠造口术。术后予以规律化疗,分析术后并发症及预后。结果54例直肠/乙状结肠转移(84.4%),其他部位结肠转移26例,小肠转移18例;肠浆膜层及浅肌层浸润47例,深肌层及粘膜层浸润17例;上皮性癌侵及肠粘膜者4例(7.7%),生殖细胞肿瘤无一例侵及肠粘膜;行肿瘤剥除44例,肠切除20例;直肠乙状结肠切除 吻合14例,6例行结肠造口。达到理想细胞减灭术56例(87.5%),其化疗后缓解率为58.9%,部分切除者8例化疗缓解率为12.5%;49例规则化疗者缓解率为65.3%,未完成充分化疗者为15.4%。术后并发症发生率26.6%,2例死于腹膜炎。结论肠道是卵巢癌的常见转移部位,肠道的肿瘤剥除和肠切除术是达到理想肿瘤细胞减灭术的先决条件,术后规则化疗能改善卵巢癌患者预后。  相似文献   
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