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991.
992.
Soichi Hotta Hiromasa Kashimura Shinji Hirai Akira Nakahara Hisayuki Fukutomi Toshiaki Osuga Yasuo Uchiyama 《Lasers in surgery and medicine》1995,16(3):262-271
Background and Objective: To further understand the precise process of the tumor cell degeneration after photodynamic therapy (PDT), laser hyperthermic therapy (LH), and combined treatments using an Nd:YAG laser. It is important to examine initial morphological alteration of tumor cells after these treatments. Study Design/Materials and Methods: In this study, nude mice bearing HeLa cell tumors were treated with PDT, LH, and combined treatments of the two. Tumor tissues obtained immediately after these treatments were analyzed using electron microscopy and morphometry. Results: In the combined treatments, which produced more severe effects on tumor cells, morphological features of apoptosis such as cytoplasmic condensation, blebs, and apoptotic bodies appeared in the cells, although the typical alteration in the nuclear chromatin was not seen. Conclusion: Cytoplasmic alterations may proceed more rapidly than nuclear alterations in the cellular degeneration induced by the single or combined treatments of PDT and LH. 相似文献
993.
994.
细胞标记用大粒径羧化彩色高分子微球的研制 总被引:1,自引:0,他引:1
制备一种普通光学显微镜下可见的细胞标记用大粒径彩色高分子微球。以苯乙烯及丙烯酰胺为原料,在体系中加入电解质,有机溶剂及油溶性染料,采用无乳化剂乳液聚合法制备彩色高分子微球,并通过酰肼化和羧化两步反应在微球表现衍生出羧基。 相似文献
995.
1. The effects of graded doses of the α2-adrenoceptor agonists clonidine, tizanidine and BHT-920, and the α2-adrenoceptor antagonists yohimbine and idazoxan, on gastrointestinal transit were investigated in mice using the charcoal meal test. 2. The agonists produced significant and dose-dependent decreases in gastrointestinal transit, and the antagonists produced the opposite effect. In affecting the gastrointestinal transit, clonidine (1 mg/kg) was as effective as tizanidine (12 mg/kg) and BHT-920 (40 mg/kg), while yohimbine (2 mg/kg) was as effective as idazoxan (1 mg/kg). 3. Morphine (2, 4 and 8 mg/kg) significantly inhibited gastrointestinal transit. This effect was significantly reversed by the co-administration of yohimbine (2 mg/kg) and idazoxan (1 mg/kg). 4. The acute administration of glucose (5.04 g/kg, i.p.) potentiated the inhibition of gastrointestinal transit produced by clonidine (1 mg/kg) and BHT-920 (40 mg/kg). Glucose treatment, however, had no significant effect on the increase in gastrointestinal transit induced by yohimbine (2 mg/kg) or idazoxan (1 mg/kg). 5. Castor oil (0.25 mL/mouse, orally) induced diarrhoea in saline-treated animals within about 45 min. Clonidine (1 mg/kg), tizanidine (12 mg/kg) and BHT-920 (40 mg/kg) delayed the occurrence of diarrhoea to 2.1, 1.2 and 1.4 h, respectively. 相似文献
996.
消化性溃疡中医辨证分型与胃液微量元素 前列腺素E_2及IgG的关系 总被引:1,自引:0,他引:1
为了探讨消化性溃疡中医辨证分型与胃液生化、免疫成分的关系,笔者将胃镜确诊的65例患者进行辨证分型,并同步检测其胃液常量元素、微量元素、前列腺素E_2-(PGE_2)、IgG等指标。结果发现,肝胃不和型胃液镁、铜、锌含量低于正常值,IgG高于正常值;脾虚胃热型胃液钠、铜、锌、PGE_2、IgG低于正常值,而钙含量高于正常值;脾胃虚寒型铜、锌、PGE_2低于正常值,而IgG无差异。说明消化性溃疡辨证分型有其客观生化、免疫基础。 相似文献
997.
Caroline S. Drugan rea Stone Steve M. Game Stephen S. Prime 《Journal of oral pathology & medicine》1997,26(7):327-333
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes. 相似文献
998.
Adherence of Staphylococcus aureus to cultures of human peritoneal mesothelial cells 总被引:1,自引:0,他引:1
Glancey G.; Cameron J. S.; Ogg C.; Poston S. 《Nephrology, dialysis, transplantation》1993,8(2):157-162
Strains of Staphylococcus aureus, isolated from the effluentof patients with peritonitis on CAPD (continuous ambulatoryperitoneal dialysis), adhered well to both cultured human mesothelialcells and to fibronectin, but not to laminin or gelatin. Mesothelialcells grown in medium M199 exhibited more surface fibronectincompared to cells grown in MEM-Dval and demonstrated higherlevels of S. aureus adherence. Soluble fibronectin concentrations up to lOµg/ml increasedthe adherence of S. aureusto cultured mesothelial cells. Thedose-response curve was consistent with the binding of fibronectinto a saturable receptor of apparent dissociation constant (KD)= 1.7xlO10 M. This corresponds closely to the KD (2xlO10M) of the staphylococcal fibronectin-binding protein. S. aureus adherence was increased following the preincubationof mesothelial cell monolayers with interleukin-1 and was maximalafter 6 h preincubation. Treating mesothelial cells with interferon-gammafor 4872 h reduced the adherence of S. aureus. 相似文献
999.
经电镜观察,慢活肝中主要为淋巴细胞及单核巨噬细胞浸润。淋巴细胞分3型,通过4种方式与肝细胞接触,可能代表杀伤肝细胞的动态过程。与肝细胞接触的主要为起细胞毒作用的T_8~+Ⅱ型淋巴细胞及单核巨噬细胞。多数T_4~+淋巴细胞为Ⅰ型淋巴细胞,可能为T辅助细胞。在肝细胞损伤中,淋巴细胞及单核巨噬细胞均起重要作用。 相似文献
1000.
Ten (E)-and (Z)-isomers of 2-phenylcyclopropylamine (PCA), 1-Me-PCA, 2-Me-PCA, N-Me-PCA, and N, N-diMe-PCA and fifteeno
−, m−, p− isomers of (E)-PCA with substituents of Me, Cl, F, OMe, OH were synthesized in this laboratory and tested for the inhibition of rat brain
mitochondrial MAO-A and MAO-B. The effects of substituents, their positions, and stereochemistry on the inhibition were assessed
for the compounds with substituents at cyclopropyl and amino groups and QSAR analyses were performed using the potency data
of ring-substituted compounds. The best correlated QSAR equations are as follows: pI50=0.804 Π2 Blo−1.069 Blm+0.334 Lp−1.709 HDp+7.897 (r=0.945, s=0.211, F=16.691, p=0.000) for the inhibition of MAO-A; pI50=1.815 π-0.825 Π2 R+0.900 Es2+0.869 Es3+0.796 Es4−0.992 HDp+0.562 HAo+3.893 (r=0.982, s=0.178, F=23.351, p=0.000) for the inhibition of MAO-B. Based on the potency difference
between stereoisomers of cyclopropylamine-modified compounds and on QSAR results, it is proposed that the active sites of
MAO-A are composed of one deep hydrophobic cavity near para position, two hydrophobic cavities interacting with Me group,
a hydrophobic area accomodating phenyl and cyclopropyl backbone, steric boundaries, a hydrogen-acceptor site near para position,
and an amino group binding site and that in addition to the same two hydrophobic cavities, hydrophobic area, steric boundaries,
hydrogen-acceptor site, and amino group binding site, another steric boundary near para position and a hydrogen donating site
near ortho position constitute active sites of MAO-B. 相似文献