高效液相色谱法测定胞苷酸混合液中各组分的含量

目的建立高效液相色谱法(HPLC)测定胞苷酸混合物中各成分(胞苷、胞苷一磷酸、胞苷三磷酸等)含量的检测方法。方法采用WAX 1阴离子交换柱(5 0mm×4mm) ,以0 .4 8mol/L磷酸二氢钾溶液(pH 5 .0 )为流动相,流速1.0ml/min ,检测波长2 6 0nm ,测定胞苷酸中各组分的含量。结果胞苷、胞苷一磷酸、胞苷二磷酸、胞苷三磷酸的线性范围分别为10～6 0 0 ,2 0～6 0 0 ,2 0～80 0 ,2 0 0～5 0 0 0 μg/ml,4种胞苷酸的平均回收率为98.0 %～10 0 .9%。结论该方法具有分析时间短,线性范围宽,灵敏准确等优点,可用于胞苷酸混合物中各组分的含量测定     

Prolonged focal application of polyethylene glycol induces conduction block in guinea pig spinal cord white matter.

A 2-min focal application of Polyethylene Glycol (PEG) to injured mammalian spinal cords can offer significant yet limited restoration of functional and structural integrity. However, longer application of PEG has not been tested in similar injuries. In this study, isolated spinal cord white matter strips from adult guinea pigs were subjected to a 25 min exposure of PEG (MW: 2000; 50% w/w), with or without prior compression. When applied in a continuous steam, PEG, with a delay of about 6 min, suppressed the compound action potential (CAP) amplitude to 64+/-4% of the pre-PEG level in uninjured cords and to 64+/-7% in compressed cord strips. Both recovered to 70+/-5% (uninjured) and 88+/-11% (compressed) of the pre-PEG level following wash. When PEG was applied in a pulsatile manner, no significant decrease of CAP amplitude was observed. In summary, our results show that focal continuous application of PEG has minimal toxicity if applied for less than 5 min. Pulsatile application could extend this duration to at least 25 min with no toxicity. This study could be useful in determining the optimal protocol for the use of PEG in both animal research and human spinal cord victims.     

固本壮骨胶囊治疗原发性骨质疏松症的临床研究

目的：评价固本壮骨胶囊的疗效和女全性。方法：我们于2002年10月至2003年7月按照国家药品食品监督管理局中药新药审批办法，通过与骨松宝颗粒剂（无糖型）多中心、随机、双盲双模拟对照的临床观察。对223例原发性骨质疏松症（肝肾不足证）患者进行了系统的临床试验研究。结果：治疗后两组都有明确疗效，两组间没有统计学差异，但试验组在改善腰膝酸软和步履艰难这二个症状方面明显优于对照组。比较骨密度的变化，各部位3个月和6个月的骨密度改变，两组无明显差异，而试验组在提高腰椎骨密度方面优于对照组。另外，治疗组在治疗过程中无明显不良反应，治疗后的各项血液生化指标和心电图均无改变。结论：固本壮骨胶囊是一种安全有效的中药新药。     

Dexamethasone induces TrkA and p75NTR immunoreactivity in the cerebral cortex and hippocampus

Nerve growth factor (NGF) plays a crucial role in synaptic plasticity during brain development and adulthood by activating a dual receptor system composed of TrkA and p75 (p75NTR) receptors. Exogenous NGF modulates the expression of both receptors. Little is known about the ability of endogenous NGF to regulate the expression of these receptors in basal forebrain cholinergic terminals. The ability of glucocorticoids to increase NGF expression in the hippocampus prompted us to investigate whether the synthetic glucocorticoid dexamethasone (DEX) increases TrkA and p75NTR expression in NGF-target cholinergic neurons in developing rats. We first examined the effect of DEX on NGF mRNA by in situ hybridization. DEX given systemically (0.5 mg/kg, sc) for 1 week to 7-day-old rats elicited an increase in NGF mRNA levels in the dentate gyrus of the hippocampus and superficial layers II and III of the cerebral cortex. Immunohistochemical analysis of p75NTR and TrkA levels revealed a dramatic increase in p75NTR immunoreactivity (IR) in both basal forebrain and hippocampus and TrkA IR in the hippocampus. Interestingly, in DEX-treated rats more axonal terminals were immunopositive for p75NTR in the hippocampus and cortex, suggesting an increase in p75NTR IR in cell bodies as well as in terminals. Our data indicate that the endogenously produced NGF elicits biological changes similar to those of the exogenously delivered NGF. We suggest that glucocorticoids might regulate and coordinate cholinergic neuronal maturation by increasing the biosynthesis of NGF.     

准分子激光角膜切削术治疗高度、超高度近视眼术后角膜上皮下混浊的远期观察

目的:探讨准分子激光角膜切削术(PRK)治疗高度、超高度近视眼术后角膜上皮下雾状混浊(Haze)的发生情况及影响因素。方法:应用日本NIDEKEC-5000型准分子激光仪治疗高度、超高度近视眼143例(245眼),I组:-6.25～-10.00D,167眼;Ⅱ组-10.25～-24.00D,78眼。观察术后不同时期Haze的发生情况,随访7a以上。结果:术后3mo,0.5,1,4,7a,Haze的发生率,I组分别为74.8%,44.3%,24.5%,11.9%,7.8%;Ⅱ组为80.7%,52.1%,33.3%,24.3%,19.2%。7a时I组屈光度-0.57±1.84D,Ⅱ组-5.02±4.26D。有3级Haze7眼,I组2眼,为RK术后者;Ⅱ组5眼,4眼为年龄>40岁者。≥3级Haze者多出现在Ⅱ组,3～6mo达到高峰,持续时间达1a以上。结论:Haze为高度、超高度近视眼PRK术后的主要并发症。预矫屈光度越高,切削越深,则混浊程度越重;部分患者Haze逐渐减轻,角膜组织创伤修复时间长,部分重度Haze日后可能成为永久性瘢痕。     

兴奋性氨基酸与青光眼

近年来随着对青光眼性视神经病变机制的深入研究,已证实兴奋性氨基酸与青光眼视网膜神经节细胞凋亡密切相关。21世纪青光眼的治疗模式正从传统的单纯降眼压向降眼压的同时从其他途径进一步加强神经保护转变,基础实验及部分临床研究证实干扰兴奋性氨基酸产生神经毒性的各环节均对神经元有保护作用,由此可以推测通过对兴奋性氨基酸的研究有望实现青光眼治疗史上的重大突破。     

人工晶状体的设计对后囊膜混浊的影响

后囊膜混浊是白内障囊外摘除术后最主要的并发症之一。后囊膜混浊的发生是多因素参与的结果,手术方式的改进、人工晶状体的改良、术后炎症反应的控制都可以减少后囊膜混浊的发生。本文就人工晶状体的设计对后囊膜混浊的影响作一综述。     

超声乳化白内障摘除治疗晶状体溶解性青光眼的临床效果

目的:探讨超声乳化白内障摘除治疗晶状体溶解性青光眼的效果。方法:对25例晶状体溶解性青光眼患者控制眼压后行白内障摘除联合人工晶状体囊袋内植入术,观察术中、术后并发症,术后视力及眼压。结果:所有患者手术顺利,后囊完整,术后视力恢复好,眼压得到控制。所有患者无明显术中、术后并发症的发生。结论:超声乳化白内障摘除治疗晶状体溶解性青光眼安全有效。     

国际旅行卫生保健信息管理探讨

目的应对我国入世,加强国际旅行卫生保健信息化建设.方法从我国加入WTO角度,信息化管理在国际旅行卫生保健中的基本职能、规范化应用及其管理优势进行探讨.结果加强国际旅行卫生保健信息规范化建设,可获得准确、及时、可靠的信息反馈,为国际旅行卫生保健提供决策依据.结论加强国际旅行卫生保健信息化建设,是建立风险预警快速反应机制的必要.     

OrbscanⅡ系统在测量晶状体厚度、眼轴及前房深度中的应用

目的　探讨 Orbcan 系统在测量前房深度、晶状体厚度及眼轴长度中的应用价值。方法　 31例 (6 2只眼 )正视眼成人 ,分别用 Orbcan 系统与 A超进行测量比较其前房深度、晶状体厚度及眼球轴长。结果　 Orbcan 系统测量中央前房深度、晶状体厚度、眼轴长度分别为 (3.5 2± 0 .2 6 ) mm、(4 .0 9± 0 .2 6 ) m m、(2 5 .5 6± 0 .85 ) m m;A超测量结果分别为 (3.4 5± 0 .36 ) mm、(3.99± 0 .36 ) mm、(2 3.72± 0 .79) mm。两者眼轴指标测量差异有显著性 (P <0 .0 0 1 ) ,其余两指标的差异均无显著性。结论　 Orbcan 系统在测量前房深度、晶状体厚度方面具有较高的应用价值 ,但在测量眼轴方面准确性欠佳