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61.
李刚  Ronald  Y  Chu 《海南医学院学报》1999,5(3):97-101
目的:研究蛋脑啡肽对猴免疫缺陷病毒(SIV)感染CEM×174 细胞kappa 阿片受体表达的调节作用。方法:用SIV 感染CEM×174 细胞并加入不同浓度蛋脑啡肽。在24 h 提取RNA,用RT-PCR 方法扩增kappa 阿片受体m RNA 并且进行定量分析。结果:显示SIV 能够抑制CEM×174 细胞的生长。在10- 7m ol/L蛋脑啡肽存在下,SIV 对细胞的损害减轻。10- 7m ol/L和10- 6m ol/L蛋脑啡肽不能改变正常细胞kappa 阿片受体的表达,但是在SIV 感染组的表达显著增高。结论:实验结果提示蛋脑啡肽能够维持正常淋巴细胞的生长。Kappa 阿片受体表达的改变可能与蛋脑啡肽对免疫细胞的调节机理有关  相似文献   
62.
PURPOSE: Mitomycin C (MMC) is commonly administered during filtering surgery to enhance the success of the procedure. Unfortunately, the increased success rate is associated with complications, including late bleb leaks, endophthalmitis, and ciliary epithelial toxicity. The purpose of this study was to investigate a safe and effective dose regimen for MMC to reduce incidence of those complications. METHODS: Trabeculectomy was performed in 36 rabbits. MMC was applied only during surgery, only one day after surgery, or once daily after surgery for 3 days at lower concentrations. Balanced salt solution (BSS) was administered during surgery to one group as a placebo. The time to bleb failure was determined and the eyes were evaluated histopathologically. Success and toxicity were compared for the different treatment groups. RESULTS: The mean time until trabeculectomy failure was 2.83 days for the placebo group, 6.33 days with administration of MMC 0.5 mg/mL during surgery, 7.83 days with administration of MMC 0.5 mg/mL once after surgery, and 11, 9, and 4.83 days with administration of MMC 0.1 mg/mL, 0.05 mg/mL, or 0.025 mg/mL, respectively, once a day for 3 consecutive days. On electron microscopic examination of the ciliary epithelium, toxic effects were greatest with MMC concentrations of 0.5 mg/mL and were less with lower concentrations. CONCLUSION: The effect of MMC on trabeculectomy survival was dependent on both the concentration and the method of administration. Lower concentrations with multiple postoperative administrations were as effective as but caused less ciliary body toxicity than intraoperative administration of higher concentrations.  相似文献   
63.
It has been reported that nonsteroidal anti-inflammatory drugs (NSAIDs) suppress bone repair and bone remodeling but only mildly inhibit bone mineralization at the earlier stage of the repair process. We proposed that the proliferation and/or the earlier stage of differentiation of osteoblasts may be affected by NSAIDs. This study was designed to investigate whether NSAIDs affect the proliferation and/or differentiation of osteoblasts and whether these effects are prostaglandin (PG) mediated. The effects of PGE1 and PGE2, indomethacin, and ketorolac on thymidine incorporation, cell count, intracellular alkaline phosphatase (ALP) activity, and Type I collagen content in osteoblast-enriched cultures derived from fetal calvaria were evaluated. The results showed that both PGs and NSAIDs inhibited DNA synthesis and cell mitosis in a time- and concentration-dependent manner. However, intracellular ALP activity and Type I collagen content were stimulated at an earlier stage of differentiation in osteoblasts. These results suggested that (i) the inhibitory effect of ketorolac on osteoblastic proliferation contributes to its suppressive effects on bone repair and remodeling in vivo; (ii) PGEs and NSAIDs may be involved in matrix maturation and biologic bone mineralization in the earlier stage of osteoblast differentiation; and (iii) the effects of ketorolac and indomethacin on cell proliferation and differentiation may not be through the inhibition of the synthesis of PGE1 or PGE2.  相似文献   
64.
细辛脑片剂的生物利用度   总被引:17,自引:0,他引:17  
目的 :比较两种不同生产工艺的细辛脑片剂生物利用度。方法 :18名健康志愿者单剂量随机交叉口服不同生产工艺的片剂 1和片剂 2 16 0mg ,及静脉注射细辛脑针剂 16mg后 ,用反相高效液相色谱法测定细辛脑血清浓度 ,对AUC0~∞ ,Cmax和Tmax3个参数进行等效性检验。结果 :片剂 1和片剂 2的绝对生物利用度分别为 (5 .4± 1.6 ) %和 (9.7± 2 .5 ) % ,片剂 2对片剂 1的相对生物利用度为 (181.9± 15 .2 ) %。结论 :经生产工艺改造后的片剂 2生物利用度比原生产工艺片剂 1提高81.9% ,但是 ,细辛脑片剂的绝对生物利用度仍很低。  相似文献   
65.
目的在简介磷脂的基础上 ,概括了磷脂类似物和磷脂聚合物的合成方法及其在医药领域中的应用。方法在参阅国内外相关文献的基础上 ,进行分析、整理和归纳。结果磷脂聚合物的合成方法已经发展的比较成熟 ,但是在医药方面的应用主要限于磷脂聚合物型脂质体、聚乙二醇(PEG)修饰型脂质体和磷脂修饰型聚合物。结论具有两亲性和生物相容性的磷脂及其聚合物在医药领域具有广泛的发展前景  相似文献   
66.
67.
针刺手法的运用是针灸临床治疗的一个关键环节。针刺手法的基本功锻炼是提高针刺手法操作技术的重要途径。本文详细介绍了针刺手法基本功锻炼的步骤和方法。  相似文献   
68.
Objectives: To describe the physical growth patterns of infants born to narcotic dependent mothers (INDM) over a 12 months period and, if possible, to relate the growth to drug taking patterns during pregnancy.
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM.  相似文献   
69.
This study was designed to look at the differences in visuospatial abilities between boys and girls before they can speak fluently. At the mandatory two year follow up visit, children were given the opportunity to build a tower and a bridge. In children whose birth weight was > or = 2500 g, the capacity for erecting a tower was the same in both sexes, but for building a bridge striking differences were noted according to their sex. Among the 376 children of this category, 41 out of 199 boys (21%) were able to build a bridge in comparison with 15 out of 177 girls (8%). This difference is highly significant. In children whose birth weight was < or = 2500 g, no differences were noted either for building a tower or a bridge. By showing that boys outnumber girls among the most skilled toddlers in spatial abilities, this work confirmed the action of a male related factor on cerebral lateralisation.  相似文献   
70.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
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