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81.
Target-derived cardiotrophin-1 and insulin-like growth factor-I promote neurite growth and survival of developing oculomotor neurons 总被引:1,自引:0,他引:1
Several trophic factors support the survival of developing motoneurons, but it is not known whether these factors act in a retrograde fashion from the motoneuron target muscle or are derived from other sources. Cardiotrophin-1 (CT-1) and the insulin-like growth factors (IGFs) are candidate target-derived motoneuron survival factors as both are expressed in muscle during naturally occurring motoneuron death and, applied systemically, support the survival of developing motoneurons. By using the embryonic chick oculomotor system, we show that CT-1 and IGF-I promote neurite outgrowth from E13-derived oculomotor explants and are retrogradely transported from muscle to nerve cell body in vivo, and injection of CT-1 or IGF-I into eye muscles increases motoneuron survival by 20 and 30%, respectively, as evidenced by calibrated stereological counting techniques. Pharmacological depletion of endogenous target-derived IGF-I in vivo reduces oculomotor neuron survival by up to 30% in a dose-dependent manner. These results significantly extend previous studies using systemic administration of trophic factors and are the first to demonstrate a target-derived retrograde mechanism of developing motoneuron survival factors. 相似文献
82.
FR Kaufman G Costin DW Thomas FR Sinatra TF Roe HB Neustein 《Archives of disease in childhood》1984,59(8):787-789
The diagnosis of optic nerve hypoplasia and hypopituitarism must be entertained in infants who present for evaluation of cholestatic jaundice, particularly if there is associated hypoglycaemia and wandering nystagmus. Although the hepatic dysfunction seems to resolve, the long term prognosis of liver disease in optic nerve hypoplasia remains unknown. 相似文献
83.
0 引言 甲型肝炎病毒 (HAV)是危害人类健康的致病原之一 ,目前已有多种用于接触前预防的甲肝疫苗 ;但对于接触后预防或短期到 HAV高流行区的旅游者的预防 ,则多采用免疫球蛋白作被动免疫 .在接触后 (14d内 )和潜伏期早期 ,注射免疫球蛋白预防甲肝的有效率达 85 %左右 .血源性免疫球蛋白虽然效价高 ,应用效果好 ,但可能被血源病原体污染 .因此基因工程人源抗体有望成为接触后预防的首选制剂 .我们从人源噬菌体抗体组合文库中筛选到一株甲肝特异性抗体 [1 ] ,在此基础上构建了可溶性表达载体 ,并获得可溶性表达 ,为该抗体的进一步研究打… 相似文献
84.
0 引言 骨形成蛋白 (Bone morphogenetic Proteins,BMPs)属于 TGF- β超家族 ,最初从牛的脱矿骨骨基质提取出来 ,在活体内可诱导异位成骨 .但近年来的研究表明 ,BMPs还是生长和发育中的调控分子 .为了探讨 BMPs在颅面部发育过程中的表达、区域及变化 ,为进一步研究颅面部畸形 (如腭裂、唇裂、牙齿发育畸形等 )的发生机制打下基础 ,作者检测了BMP2 ,4在颅面部各组织正常发育中的表达模式 .1 材料和方法1.1 材料 BAL B/ c近交系孕鼠在妊娠期第 14,15 ,16日分别被脱椎处死 ,取胎鼠头部固定于 40 g· L- 1多聚甲醛 ,常规脱水包埋… 相似文献
85.
Zeyneloglu HB; Senturk LM; Seli E; Oral E; Olive DL; Arici A 《Human reproduction (Oxford, England)》1998,13(5):1194-1199
Abdomino-pelvic adhesions arise from infection, endometriosis, or
peritoneal injury during surgery, and represent a significant source of
morbidity in women of reproductive age. Monocyte chemotactic protein-1
(MCP-1) plays a role in the chemotaxis of mononuclear cells and fibroblasts
in a murine wound repair model. To evaluate the role of MCP- 1 in
intraperitoneal adhesion formation, we investigated peritoneal fluid MCP-1
levels of women undergoing laparoscopy. Patients without endometriosis were
divided into two groups: normal fertile women undergoing bilateral tubal
ligation without intraperitoneal adhesions (n=14) and women with pelvic
adhesions (n=8). Patients with endometriosis were arranged into two groups:
women with (n=17) and without (n=17) adhesions. Peritoneal fluid MCP-1
levels were quantified using an enzyme-linked immunosorbent assay (ELISA).
Peritoneal biopsy samples were immunostained for the detection of MCP-1
protein and macrophages, and were also processed for the presence of MCP-1
mRNA expression. Among women without endometriosis, the median peritoneal
fluid MCP-1 level was 144 pg/ml (range 54-261) in women without adhesions
and was 336 pg/ml (range 130-2494) in women with adhesions (P=0.01). There
was a significant correlation between adhesion scores and MCP-1 levels
(r=0.50; P=0.018). Among women with endometriosis, peritoneal fluid MCP-1
levels significantly correlated with the stage of the disease. The presence
or absence of adhesions did not significantly affect the peritoneal fluid
MCP-1 levels in this group of women. In summary, we have found that women
with adhesions have elevated peritoneal fluid MCP-1 levels. However, we
were not able to show an incremental effect of adhesions on peritoneal
fluid MCP-1 levels of patients with endometriosis. Thus, we conclude that
factors besides the intraperitoneal adhesions contribute to the elevated
peritoneal fluid MCP-1 levels in patients with endometriosis.
相似文献
86.
运用模糊聚类方法分析中药微量元素含量与药效的关系 总被引:2,自引:0,他引:2
目的:不同中药中各种微量元素的含量数据离散,从含量数据上很难说明不同药物的药物相似性,故运用模糊分类方法研究药物微量元素含量与药物疗效的关系,验证其在药物功效的相似性及不同种类中药定量指标评价方面的作用。方法:实验于2005-10/2006-11在吉林省中医药管理局中药微量元素分析实验室完成。用原子吸收分光光度法检测合欢花、黄芪、石菖蒲、远志、山楂、银杏叶、人参、元肉、蒲黄、酸枣仁、苏木11种中药中钾、钠、钙、镁、铁、铬、镍、锰、铜、锌元素的含量,结合锌/铜比值、镁/钙比值,以数据极差法进行统计指标的标准化处理,以数量积法算出衡量被分类对象之间的相关系数,确定论域上的模糊矩阵。结果:相关系数r=0.50时,合欢花,石菖蒲,远志,人参,元肉,蒲黄,酸枣仁7种药物聚类相似;相关系数r=0.65时,合欢花,石菖蒲,元肉,蒲黄,酸枣仁5种药物聚类相似;r=0.75时,合欢花,石菖蒲,蒲黄3种药物聚类相似。研究还发现:药物中金属元素含量丰富,而且相关系数较大的药物,其药物疗效相似。结论:运用数学与化学计量学方法建立模糊聚类分析模型,可以把离散的数据标准化处理,确定论域上的模糊矩阵可以研究不同药物间的药效相似性,可以对不同种类的中药进行定量指标的明确评价。 相似文献
87.
88.
商陆多糖I对小鼠脾淋巴细胞增殖及脾淋巴细胞、巨噬细胞分泌细胞因子的影响 总被引:2,自引:0,他引:2
商陆多糖Ⅰ(Phytolacca acinosa polysaccharides Ⅰ,PAP-Ⅰ)体外能显著促进小鼠脾淋巴细胞增殖,促进丝裂原诱导的淋巴细胞转化及双向混合淋巴细胞反应。检测PAP-Ⅰ和小鼠脾淋巴细胞培养上清液发现PAP-Ⅰ可显著促进小鼠脾淋巴细胞产生白细胞介素2(IL-2)及集落刺激因子(colony stimulating factor,CSF)。PAP-Ⅰ和小鼠腹腔巨噬细胞培养上清液中也存在CSF活性及促进重组粒单系集落刺激因子诱导骨髓细胞增殖的细胞因子。PAP-Ⅰ,ip可显著促进小鼠脾淋巴细胞增殖及IL-2产生。 相似文献
89.
赛庚啶对氧自由基的清除作用 总被引:18,自引:0,他引:18
赛庚啶(Cyp)对Fenton反应生成的·OH有较强的直接清除作用(EC50为54μmol/L),并明显抑制·OH的生成速率(IC50为22 μmol/L),且作用明显比·OH特异性清除剂甘露醇强(其EC50和IC50分别为22.7 mmol/L和10.7mmol/L)。Cyp对大鼠腹腔多形核白细胞(PMNs)产生的O2也有一定的清除作用,其IC50为179 μmol/L。提示Cyp的抗心肌损伤作用可能至少部分与其清除氧自由基作用相关。 相似文献
90.
Vasoactive amines directly modify endothelial cells to affect polymorphonuclear leukocyte diapedesis in vitro 总被引:3,自引:0,他引:3
Bovine aortic endothelial cells were cultured on the basement membrane surface of amnionic membrane and used as a substrate for polymorphonuclear leukocyte (PMN) diapedesis in vitro. Norepinephrine (NE), serotonin (5HT), or phalloidin treatment of the endothelial cells (ECs) reduces, whereas histamine or cytochalasin B increases, the number of PMNs migrating across the ECs and amnionic membrane. In contrast, amine treatment of PMNs or acellular amnionic membrane does not alter PMN diapedesis or chemotaxis. The NE and histamine effects are blocked by appropriate receptor antagonists, but the 5HT effect is not. All the agents' effects are also reversible. Qualitatively similar effects on EC permeability to Evan's blue-labeled albumin occur with all agents; however, PMN adhesion to ECs is not affected. Previously, we reported that NE and 5HT increase stress fiber numbers and decrease EC permeability to macromolecules in vitro, whereas histamine has the opposite effects, and that NE and 5HT eliminate the erythrocyte extravasation associated with thrombocytopenia in vivo. In this study, we propose that these vasoactive amines also alter PMN diapedesis in vitro through a direct effect on the EC, in part due to alterations in the EC cytoskeleton. 相似文献