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991.
邓新国  吴景兰 《眼科研究》1999,17(4):244-246
目的 研究8-Br-cAMP对培养的人视网膜母细胞瘤HXO-Rb44细胞癌基因表达的效应及其与该细胞生长的关系。方法 c-fos mRNA,N-myc mRNA及p21ras mRNA均以原位杂交RNA斑点印迹技术检测,对繁殖细胞核抗原,v-Fos,N-Myc和P^21ras蛋白表达的免疫反应性则采用免疫组化及收白质斑点印迹技术检测。  相似文献   
992.
原癌基因bc1 2属抗凋亡基因 ,它不促进细胞增殖 ,但能延长细胞的生命期限。Bc1 2在许多细胞增殖性疾病的发生中起着非常重要的作用。通过影响组织细胞内bc1 2基因的表达 ,为临床上一些退行性疾病及细胞增殖性疾病的治疗提供新的思路。Bc1 2在眼科领域的研究主要集中于遗传性和环境因素所致的视网膜变性。Bc1 2的过表达可以阻止实验性缺血、视神经挫伤、光诱导损伤以及一些视蛋白和cGMP磷酸二酯酶缺陷所致的视网膜光感受器凋亡 ,但对由于某些基因突变所致的凋亡无阻止作用  相似文献   
993.
角膜缘干细胞与结膜移植治疗翼状胬肉   总被引:1,自引:0,他引:1  
王小云  张琦 《眼科学报》1999,15(2):89-90
目的:观察角膜缘干细胞与结膜移植治疗翼状胬肉的疗效。方法:采用自体角膜缘干细胞与结膜移植术,对38例43眼初发和复发性翼状胬肉患者进行治疗,术后随访3~30月,平均10月。结果:38例43眼中34例38眼上皮愈合稳定,角膜恢复正常光滑、透明,胬肉无复发。4例5眼失访。结论:自体角膜缘上皮移植为病变区角膜和结膜提供新的干细胞来源,是治疗翼状胬肉的理想方法。眼科学报1999;15:89—90。  相似文献   
994.
Luteolytic effects of DL111-IT in pregnant rats   总被引:3,自引:0,他引:3  
The present studies were conducted to evaluate the effects of DL111-IT [3-(2-ethyl phenyl)-5-(3-methoxy phenyl)-1H-1,2,4 triazol] on ovaries of pregnant rats. Pregnant rats were i.m. treated with DL111-IT 2.5 mg kg(-1) day(-1) or camellia oleum (vehicle control) 0.2 ml/day from day 6 of pregnancy for 1, 3 or 5 days. Blood and ovaries were collected 24 h after the last injection. Ovarian fresh weight and protein contents, activities of the 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) in ovaries, and cell apoptosis of corpus luteum (including hematoxylin-eosine stain, in situ 3'-end labeling and nucleosomal banding) were estimated. Compared with that in the control group, ovarian fresh weight declined 11% and 22% after DL111-IT-3 days and -5 days; protein content dropped 29% after 5-day administration. DL111-IT for 3 days provoked a marked decrease of serum progesterone, by 31% of the control; the activity of 3beta-HSD decreased 34.4% after i.m. DL111-IT for 5 days, while that of 20alpha-HSD increased dramatically after only one injection of DL111-IT (P < 0.01). Histological analysis and in situ 3'-end DNA labeling indicated that DL111-IT induced the pyknosis of cells and the formations of apoptotic bodies and intense oligonucleosomes in luteal cells of pregnant rats. The cell apoptosis induced by DL111-IT was further confirmed by evaluation of nucleosomal DNA fragmentation by agarose gel electrophoresis in cultured luteal cells exposed to DL111-IT for 24 h. In conclusion, all results, including shrunken luteal cells, decreased concentration of protein content and serum progesterone, changed activities of 3beta-HSD and 20alpha-HSD and formation of DNA fragments in luteal cells, showed the luteolytic effect of DL111-IT in pregnant rats.  相似文献   
995.
996.
Fifteen patients with Stage IIIB or IV non-small cell lung cancer gave informed consent to receive three or more 96-hour infusions of ATP at a dose of 50 mcg/kg/min or higher to determine whether ATP has antineoplastic activity against this tumor type and to better define the spectrum of toxicity for ATP given as a single agent. There were no objective complete or partial responses observed. The median survival of the overall group was 187 days and the median time to tumor progression was 113 days. The major toxic side effects were chest pain and dyspnea, leading to the cessation of treatment in 5 patients. We conclude that ATP at this dose and schedule of administration is an inactive agent in patients with advanced non-small cell lung cancer.  相似文献   
997.
卵巢肿瘤增殖细胞核抗原的表达及意义   总被引:3,自引:0,他引:3  
袁碧波  刘姝华 《天津医药》1999,27(12):731-733
目的:研究增殖细胞核抗原(PCNA)在卵巢肿瘤中的表达及意义。方法:应用免疫组化ABC法检测133例卵巢肿瘤和12例正常卵巢组织PCNA的表达。结果:卵巢肿瘤与正常卵巢组织的PCNA表达有显著性差异。良性、交界性、恶性组PCNA表达呈上升趋势(P〈0.05)。病理分类上皮性组PCNA表达显著高于非上皮性组(P〈0.05)。在上皮性组中,中、低分化组PCNA表达高于高分化组,晚期表达高于早期(P〈0  相似文献   
998.
Proliferating cell nuclear antigen (PCNA) and transforming growth factor (TGF) are considered as markers of cell proliferation. The expression of PCNA and TGF was evaluated immunohistochemically using anti-PCNA antibody and TGF in 31 patients with biliary atresia (BA) (15 jaundice-free and 16 with persistent jaundice) and 6 control infants. The labeling indices (LI) for PCNA- and TGF-positive bile-duct epithelium in BA were 14.1±14.0% and 51.4±33.7%, respectively, which was significantly higher than in the controls (P <0.01). In BA, the number of PCNA-immunoreactive cells was higher in the peripheral bile ductules than in the central bile ducts of the portal tract (P <0.01). LI was not related to patient age at the time of hepatic portoenterostomy in two groups divided at the age of 60 days. Patients in the persistent jaundice group had greater expression of PCNA and TGF (21.7±16.0% and 76.9±20.7%, respectively) compared to those in the jaundice-free group (6.0±2.7% and 24.3±20.9%, P <0.001). PCNA and TGF expression in the bile-duct epithelium of the portal tract was closely related to prognosis in BA patients, and thus could be useful as a prognostic marker.  相似文献   
999.
Motile properties of outer hair cells (OHCs) may contribute to sharp tuning and amplification in the mammalian cochlea. Shape changes of isolated OHCs in response to various physical and chemical influences have been investigated intensively. However, determinations of shape may have been influenced by unanticipated effects of preparation and preservation of the OHCs investigated. Thus, in a first step, lengths of freshly isolated OHCs from the guinea pig cochlea were determined using a video-enhancing magnification system. The cuticular plate/cell axis angle (CP/CA angle) was then measured in native cells and under the influence of potassium chloride and potassium gluconate incubation. To show the influence of glutaraldehyde (GA) fixation on the isolated OHCs, fixative dependent changes on cell length and CP/CA angle were recorded in native and preincubated OHCs. In these experiments, the cell length of vital isolated OHCs was between 41.5 m, in the basal turn, and 103.7 m, in the apical turn. The average CP/CA angle was 106° ± 4.2° (n = 324 cells, turns 1–4) with no statistically significant differences for the four turns. Under the influence of potassium chloride, cell length was reduced by 8.1%. Potassium gluconate incubation led to a shortening of cell length, followed by a 5.3% increase after 5 min. The CP/CA angle under potassium chloride was decreased (97.0°) and was then increased under the influence of potassium gluconate (110.7°) as a result of cuticular plate tilting. Cell shrinkage after fixation depended on the fixative's osmolarity and on the GA concentration. Increased GA levels amplified cell shrinkage from 34% for hypo-osmolar solutions to 15% in iso-osmolar and 29% in hyperosmolar solutions. The CP/CA angle of native and incubated OHCs was not different from those fixed with GA. The present data provide a rational basis for isolated OHC shape parameters. Moreover, functionally induced changes can be better interpreted when OHCs are influenced by fixatives, as shown in the GA experiments.  相似文献   
1000.
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