不同来源的N-乙酰神经氨酸裂合酶的特性及在大肠埃希菌中的表达

综述了N-乙酰神经氨酸裂合酶的特性、应用及反应机理，对不同来源的N-乙酰神经氨酸裂合酶进行了比较。简要阐述N-乙酰神经氨酸裂合酶在大肠埃希菌中的克隆表达及其纯化。     

Intracerebral transportation and cellular localisation of insulin-like growth factor-1 following central administration to rats with hypoxic-ischemic brain injury

Insulin-like growth factor-1 (IGF-1) has been shown to be neuroprotective when administered centrally following hypoxic-ischemic (HI) brain injury. However, the cerebral distribution and site of action of IGF-1 after intracerebroventricular (i.c.v.) administration are not known. A unilateral HI brain injury was induced in adult rats by a modified Levine method. Either 3H-IGF-1 alone, or in combination with unlabelled IGF-1, was administered into the lateral ventricle 2 h after injury. The activity of 3H-IGF-1 signal in the potentially injured cortex was compared between two treatment groups using image analysis. The regional distribution and cellular localisation of 3H-IGF-1 were examined autoradiographically in potentially injured hemispheres at 0.5 and 6 h after administration. Tritiated IGF-1 was detected predominantly in the pia mater, perivascular spaces and subcortical white matter tracts 0.5 h after administration and decreased by 6 h (p<0.05). The signals associated with the perivascular spaces and pia mater were not blocked by unlabelled IGF-1, suggesting non-saturable binding in these brain areas. IGF-1 signal was co-localised with IGF binding protein (IGFBP)-2 immunostaining in the white matter tracts where the signal was blocked by unlabelled IGF-1, suggesting competitive association. IGF-1 signal associated with neurons and glia was maximal in the cerebral cortex and less in the CA1-2 subregion of the hippocampus which were blocked by unlabelled IGF-1 (p<0.05). The signals from cortical neurons did not decrease 6 h after administration, suggesting specific and persistent binding to these cells. Our results indicate that centrally administered IGF-1 can be translocated to neurons and glia via the perivascular circulation and the ependymal cell-white matter tract pathways.     

N-terminal tripeptide of IGF-1 (GPE) prevents the loss of TH positive neurons after 6-OHDA induced nigral lesion in rats

The effect of the N-terminal tripeptide of insulin-like growth factor (IGF)-1, glycine-proline-glutamate (GPE), as a neuroprotective agent for nigro-striatal dopaminergic neurons was examined in the present study using a rat model of Parkinson's disease. A unilateral nigro-striatal lesion was induced in rats by injecting 6-hydroxydopamine (6-OHDA) into the right medial forebrain bundle (MFB). GPE (3 microgram) or its vehicle was administered intracerebroventricularly (i.c.v.) 2 h after the 6-OHDA lesion. Tyrosine-hydroxylase (TH) immunohistochemistry in the substantia nigra compacta (SNc) and the striatum were examined 2 weeks after the lesion. Following 6-OHDA injection, the number of TH immunopositive neurons in the ipsilateral SNc was reduced. The density of TH immunostaining was also reduced in the ipsilateral SNc and the striatum. Treatment with a single dose of GPE (n=9) significantly prevented the loss of TH immunopositive neurons (p<0. 001) and restored the TH immunoreactivity in both the SNc and the striatum compared with the vehicle control group (n=9, p<0.001). The results suggest that GPE showed promise as a potential treatment for Parkinson's disease.     

江门市3～6岁异常视力儿童屈光状态分析

目的了解江门市异常视力儿童屈光状态。方法对江门市幼儿园的8510名3～6岁儿童进行视力普查。对单眼裸眼视力<0.9者(1116例2232只眼)的屈光状态及弱视患儿的屈光状态进行了分析。结果屈光不正总患病率为13.01%;远视、混合散光、近视患病率依次为9.85%、2.36%、0.80%(P<0.05);轻、中、重度屈光不正患病率依次为7.34%、3.96%、1.70%(P<0.05);屈光不正有年龄特点(4岁组患病率高于其他年龄组);弱视患病率为3.74%;弱视首次检出率为88.23%。结论远视性屈光不正是导致弱视的主要原因。     

儿童维生素A缺乏与感染性疾病的关系

[目的]了解儿童血清维生素A缺乏(vitamin A deficiency,VAD)与感染性疾病的关系. [方法]在避光条件下采集儿童指血、分离血清,以严格的质量控制,用微量荧光法检测血清维生素A(vitamin A,VA)浓度. [结果]两周内不同地区儿童发热率、急性呼吸道感染(ARI)、腹泻,发病率随血清VA缺乏率的增加而增加;儿童平均血清VA的含量随发热率、发病率的增加而下降. [结论]我国儿童血清VA含量低、缺乏率高的儿童不论个体或群体都表现为易于发生急性感染疾病,VAD是引起儿童易于发生急性感染性疾病的重要原因之一.     

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。     

增生性糖尿病视网膜病变弥漫性黄斑水肿的激光治疗

目的　评价全视网膜光凝联合黄斑格栅样光凝治疗伴有弥漫性黄斑水肿的增生性糖尿病视网膜病变的疗效。方法　 4 0例 5 0眼伴有弥漫性黄斑水肿的增生性糖尿病视网膜病变患者 ,采用氩绿激光进行黄斑格栅样光凝联合全视网膜光凝。分析视力、黄斑水肿和新生血管的变化。结果　激光治疗后随访 6～ 30个月 ,5 0眼中 36眼治疗有效 ;76 %患眼的视力稳定 ,视力进步者占 12 % ;6 2 %患眼黄斑水肿明显减少 ,黄斑水肿完全消退者占 10 % ;视网膜新生血管或视盘新生血管完全消退者为 12 % ,部分消退者为 5 6 % ,余 14眼 (2 8% )治疗无效。结论　全视网膜光凝联合黄斑格栅样光凝是治疗伴有弥漫性黄斑水肿的增生性糖尿病视网膜病变的有效措施。     

山西省出生缺陷高发区居民饮水中硝酸盐和亚硝酸盐含量研究

目的了解山西省出生缺陷高发地区饮水中硝酸盐和亚硝酸盐含量。方法选择山西省太原市、太谷县和平定县作为研究现场,采集当地居民不同类型的饮用水测定硝酸盐和亚硝酸盐含量。结果研究地区饮水中硝酸盐平均含量为3·5mg/L,有4·0%的样品超过我国的饮用水卫生标准。井水中的硝酸盐含量(5·1mg/L)高于自来水(2·7mg/L)。饮水中亚硝酸盐平均含量为0·004mg/L,以泉水含量最高(0·015mg/L)。结论研究地区居民饮水中硝酸盐和亚硝酸盐含量并没有显著高于文献报道的其它地区。饮水中硝酸盐和亚硝酸盐暴露在山西省出生缺陷高发中的作用可能不大。     

消渴颗粒剂质量标准的初步研究

采用薄层层析方法对我院糖尿病研究中心新制剂消渴颗粒剂中各药味分别进行了定性鉴别研究，意在为其质量控制提供参考。本研究确立了鬼箭羽、葛根、山茱萸、大黄的薄层鉴别条件，经阴性对照试验及样品实验观察，证明本实验方法可行。