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31.
Galactosylated surface is an attractive substrate for hepatocyte culture because of the specific interaction between the galactose ligand and the asialoglycoprotein receptor on hepatocytes. In this study, we described a scheme to achieve high density of immobilized galactose ligands on polyethylene terephthalate (PET) surface by first surface-grafting polyacrylic acid on plasma-pretreated PET film under UV irradiation, followed by conjugation of a galactose derivative (1-O-(6'-aminohexyl)-D-galactopyranoside) to the grafted polyacrylic acid chains. A high galactose density of 513 nmol/cm(2) on the PET surface was used in this study to investigate the behavior of cultured hepatocyte. This engineered substrate showed high affinity to fluorescein isothiocyanate-lectin binding. Primary rat hepatocytes, when seeded at a density of 2 x 10(5) cells/cm(2), attached to the galactosylated PET substrate at a similar efficiency compared with collagen-coated substrate. The hepatocytes spontaneously formed aggregates 1 day after cell seeding and showed better maintenance of albumin secretion and urea synthesis functions than those cultured on collagen-coated surface.  相似文献   
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Seventy-two cases of idiopathic pulmonary fibrosis (IPF) were examined from 2856 consecutive autopsy cases at the Japanese Red Cross Medical Center in Tokyo from 1973-1996. Primary lung cancer had arisen in 31 of 72 cases of IPF (43%), significantly higher than the incidence in cases without IPF (8.1%) and in the cases with non-IPF chronic lung diseases (11.9%). Hyperplastic epithelial foci in the honeycomb lesions of IPF cases were significantly more prominent in the lower than in the upper lobe, in cases with or without lung cancer, and they were more prominent in the lower lobe of IPF with than in those without cancer. The length of hyperplastic epithelial foci in the lower lobe of IPF cases was longer than that in interstitial pneumonia-associated with collagen vascular diseases. There was a higher PCNA labeling index of hyperplastic epithelial foci in IPF cases than in cases of interstitial pneumonia-associated with collagen vascular diseases. The PCNA labeling index was almost the same between smokers and nonsmokers with IPF. Overexpression of p53 was observed in hyperplastic epithelial foci in honeycomb lesion of IPF. DNA ploidy analysis of hyperplastic epithelial foci in the paraffin sections of 12 IPF cases revealed aneuploidy patterns in eight cases. These results strongly suggest that accelerated cell proliferation occurs in the honeycomb lesion of IPF, and that regenerative epithelia becomes susceptible to carcinogenic agents in addition to the smoking effect.  相似文献   
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热习服和热应激对血液流变性影响的实验研究   总被引:2,自引:0,他引:2  
目的探讨热应激和热习服对机体血液流变性的影响.方法观察日本大耳白兔在热应激和热习服时全血黏度、血浆黏度、血沉、红细胞比容、纤维蛋白原等指标的变化.结果1.热应激组在受热1 h组全血黏度有所下降;受热2 h组和热习服组全血黏度、血浆黏度均有明显升高;2.血沉、红细胞比容、纤维蛋白原在热习服组显著升高,热应激组在受热2 h有明显升高.结论热习服和热应激均能对机体的血液流变性产生明显影响.  相似文献   
36.
目的探讨肾下极肾盂肾盏联合切开术治疗复杂性鹿角形肾结石的疗效。方法回顾性分析采用肾下极肾盂肾盏联合切开术式治疗复杂性鹿角形肾结石34例临床资料。手术方法:分离肾窦内肾盂后,用1-0肠线在肾后唇中下1/3连接处紧贴肾盂肾盏表面缝合肾实质2针,中间尖刀切开肾实质,然后弧形切开肾盂及肾下盏,用神经剥离子将结石与肾盂肾盏粘膜粘连分离后,取石钳夹住结石轻轻撬出。盏颈狭窄者必要时先用气压弹道碎石器将其在分支处击断。4-0肠线缝合肾盂及肾下盏,再用2-0肠线间断全层缝合肾实质切口数针,包膜层用4-0肠线缝合。结果34例均一次性取净结石。术中平均出血量约90ml。术后无大出血病例。结论肾下极背侧肾实质与肾盂联合切开取石术具有术中出血少,无须阻断肾蒂,肾功能受损轻,便于一次取尽结石等优点。适合于肾窦内肾盂特别是肾下盏盏颈相对狭窄的复杂性鹿角形肾结石的治疗。  相似文献   
37.
BACKGROUND: The comparative studies of the prevalence of atopic dermatitis and skin barrier functions in Japanese and Chinese were performed. METHODS: Clinical investigations were performed in 68 elementary school students in Lhasa, Tibet Autonomous Region and 67 students in Yixing, Jiangsu Province in China, and 99 students in Nishinomiya, Hyogo in Japan. Transepidermal water loss (TEWL) and capacitance were measured. Questionary survey about bathing frequency was also performed for students in Lhasa, Yixing and Osaka. RESULT: The prevalence rate of atopic dermatitis was 0% in Lhasa, 2.63% in Yixing, 4.26% in Nishinomiya. TEWL of students in Nishinomiya was higher than that in Yixing and Lhasa. Capacitance of students in Lhasa was lower than that in Nishinomiya and Yixing. The frequency of taking a bath in Lhasa was about 2.2 times per month and fewer than that in Nishinomiya and Yixing. CONCLUSION: There was tendency that the prevalence of atopic dermatitis increased according to increase of TEWL. It was thought that more investigations are necessary whether the development of habitat and environment influence the prevalence of atopic dermatitis and skin barrier function.  相似文献   
38.
硅凝胶人工晶体的生物相容性   总被引:3,自引:0,他引:3  
本文参照国内外有关医用高分子材料的生物学评价试验方法,对国产医用级硅凝胶人工晶体作了系统的生物学评价。结果表明:硅凝胶人工晶体对眼及皮肤无刺激作用、无热原、无毒性、体外溶血率小于5%,对细胞生长有促进作用,长期植入皮下时,随植入时间延长,囊壁厚度逐渐变薄,炎性细胞反应30天基本消失。染色体及骨髓多染红细胞未受影响。因此,可以认为硅凝胶人工晶体有良好的生物相容性。  相似文献   
39.
观察了20具(40例)成人尸体的腰动脉,阐明了腰动脉的数目、起源、走行、口径、长度、起始平面与腹主动脉的夹角及相邻两腰动脉间的距离。为临床上由腰动脉插管进行的选择性脊髓造影术提供了解剖学依据。  相似文献   
40.
This is the second part of a two-part study that explores the feasibility of 3-D, volumetric brain imaging in small animals by optical tomographic techniques. In part 1, we demonstrated the ability to visualize global hemodynamic changes in the rat head in response to elevated levels of CO(2) using a continuous-wave instrument and model-based iterative image reconstruction (MOBIIR) algorithm. Now we focus on lateralized, monohemispherically localized hemodynamic effects generated by unilateral common carotid artery (CCA) occlusion. This illustrates the capability of our optical tomographic system to localize and distinguish hemodynamic responses in different parts of the brain. Unilateral carotid occlusions are performed in ten rodents under two experimental conditions. In the first set of experiments the normal systemic blood pressure is lowered to 50 mmHg, and on unilateral carotid occlusion, we observe an ipsilateral monohemispheric global decrease in blood volume and oxygenation. This finding is consistent with the known physiologic response to cerebral ischemia. In a second set of experiments designed to observe the spatial-temporal dynamics of CCA occlusion at normotensive blood pressure, more complex phenomena are observed. We find three different types of responses, which can be categorized as compensation, overcompensation, and noncompensation.  相似文献   
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