长链核酸扩增技术评价病毒灭活效果的研究

目的:探讨用长链核酸扩增技术评价病毒灭活效果的可行性.方法:针对伪狂犬病毒(pseudorabies virus,PRV)糖蛋白gD基因前后的保守区设计预计产物长短不一的5对引物,用半巢式PCR技术扩增经低pH法(4.0±0.1)、巴氏消毒法[(60±1.0)℃]和s/D法(有机溶剂/洗涤荆)处理后的PRV核酸,同时以细胞感染法做平行对照.结果:低pH对PRV核酸有破坏作用,处理时间越长,核酸损伤程度越明显,处理60 min时,6.62 lgTCID50的PRV完全被灭活.5条不同长度PCR扩增产物中,只有3.9 kb的长片段检出与细胞培养结果一致.7.25 lgTCID50的PRV经(60±1.0)℃处理20 min后即被完全灭活,7.13 lgTCID50的PRV经s/D法处理1 h后被完全灭活,但各长度核酸片段扩增均为阳性,与细胞感染试验结果不符.结论:低pH对PRV核酸的损伤程度随处理时间的延长而增加;用长链PCR(3.9 kb)技术来评价经低pH法灭活病毒的效果是可行的,而该法不适合评价巴氏消毒法和S/D法灭活病毒的效果.     

高脂血症对血浆t-PA和PAI-1活性的影响

目的 探讨高脂血症患者的纤溶系统的变化。方法 选取正常人及高脂血症者，测定其血脂、血浆t—PA和PAI-1活性。结果 高脂血症组比正常人血浆t—PA活性下降，而PAI-1的活性有升高；在TG及LDL-C升高者，其血浆t—PA活性比正常人血浆t—PA活性降低，而血浆PAI-1活性比正常人升高；单纯TC升高者血浆PAI-1活性接近正常人组，而血浆t—PA活性比正常人组明显降低。结论 高脂血症对纤溶系统有一定的影响，其中甘油三酯和LDL-C对纤溶系统的影响更明显，而胆固醇对纤溶系统也有一定的影响。     

吡格列酮对高脂饮食兔主动脉LOX-1表达的影响

目的探讨吡格列酮对高脂饮食下兔主动脉LOX-1表达的影响及其对动脉粥样硬化的作用。方法设立正常饮食、高脂饮食及高脂饮食加吡格列酮干预3组,通过比较主动脉病理形态学改变、血脂的变化、LOX-1分子及mRNA的表达进行研究,采用免疫组化检测兔主动脉LOX-1分子的表达,采用RT-PCR检测LOX-1mRNA的表达。结果吡格列酮能减轻高脂饮食所致的内膜增厚和平滑肌增生,减轻高脂血症所致动脉粥样硬化的发展。吡格列酮还能明显升高HDL,对TC、LDL、TG和BS无明显影响。高脂饮食刺激兔主动脉LOX-1分子及mRNA的表达,吡格列酮能显著减轻这种作用。结论吡格列酮能减轻高脂饮食兔主动脉LOX-1分子及mRNA的表达,这可能是噻唑烷酮类药物抗动脉粥样硬化的重要作用机制。     

Users' subjective evaluation of electronic vision enhancement systems

The aims of this study were (1) to elicit the users' responses to four electronic head-mounted devices (Jordy, Flipperport, Maxport and NuVision) and (2) to correlate users' opinion with performance. Ten patients with early onset macular disease (EOMD) and 10 with age-related macular disease (AMD) used these electronic vision enhancement systems (EVESs) for a variety of visual tasks. A questionnaire designed in-house and a modified VF-14 were used to evaluate the responses. Following initial experience of the devices in the laboratory, every patient took home two of the four devices for 1 week each. Responses were re-evaluated after this period of home loan. No single EVES stood out as the strong preference for all aspects evaluated. In the laboratory-based appraisal, Flipperport typically received the best overall ratings and highest score for image quality and ability to magnify, but after home loan there was no significant difference between devices. Comfort of device, although important, was not predictive of rating once magnification had been taken into account. For actual performance, a threshold effect was seen whereby ratings increased as reading speed improved up to 60 words per minute. Newly diagnosed patients responded most positively to EVESs, but otherwise users' opinion could not be predicted by age, gender, diagnosis or previous CCTV experience. User feedback is essential in our quest to understand the benefits and shortcoming of EVESs. Such information should help guide both prescribing and future development of low vision devices.     

极低出生体重儿两种喂养效果观察

目的:探讨极低出生体重儿(VLBW)的早期微量持续鼻饲喂养(CNG)与间断鼻饲喂养(ING)的喂养耐受性及喂养效果.方法:将60例VLBW进行随机分组,CNG组起始奶量1-2ml/h,以后泵速增加1-2ml/h.ING组奶量以1-2ml/kg开始, 以后每天增加1-2ml/kg/次.所有VLBW均同时进行部分静脉营养,直至达到完全胃肠道喂养时间(FEF).对比两组喂养不耐受性、达到FEF、停止静脉补液时间及黄疸持续时间.结果:CNG组较ING组患儿发生腹胀、呕吐者明显减少(P＜0.05),黄疸持续时间、吸吮动作出现时间及住院时间较对照组明显缩短(P＜0.05),但两组体重增长情况统计学无差异(P＞0.05).结论:CNG更适合VLBW的早期微量喂养.     

顶空—气相色谱法测定盐酸洛美利嗪中乙腈残留量

目的：建立盐酸洛美利嗪原料药中乙腈残留量的测定方法。方法：采用顶空进样法，80％DMF水溶液为溶剂，平衡温度70℃，平衡时间40min，气相色谱条件：采用不锈钢填充色谱柱：柱长2m，内径3mm，粒径为0.25-0.32mm的二乙烯苯与乙基乙烯苯共聚物有机担体为填料，柱温130℃，FID检测器，检测器温度250℃，氮气为载气，流速50mL.min^-1。结果：乙腈在23．46－234．6μg.mL^-1的浓度范围内呈良好的线性关系（r=0.9978)，回收率为96．7％（RSD＝3．8％），检出限小于40μg.g^-1。结论：本方法简单，快捷且灵敏度高，可以用于盐酸洛洛美利嗪中乙腈残留量的控制。     

An approach to protein restriction in children with renal insufficiency

Children with mild to moderate renal insufficiency may be at an increased risk for developing glomerulosclerosis and subsequent renal failure. Low protein diets (LPD) have been shown to delay the progression of renal insufficiency in laboratory animals and may be of benefit in adult humans. The nutritional costs of a LPD in adults are reportedly minimal. We review the protein and caloric requirements of growing children and discuss the potential harmful effects and benefits of an LPD in this population. We also discuss dietary adherence and the difficulty of designing an LPD for children. We conclude that the protein content of a typical American diet can safely be reduced to, but not below, the recommended daily allowance for protein if diets are carefully planned, patients and their parents extensively counseled, and if dietary supplements are given to help meet the caloric and vitamin-mineral nutrient needs of growing children. In addition, ongoing nutritional assessment, counseling, and frequent monitoring of growth, diet and biochemical indicators of protein status are essential for maintaining the health of these children.     

低分子量肝素化学及生物活性的不均一性

综述了低分子量肝素的化学和生物活性的不均一性,以及药理作用,药物动力学、临床应用等方面的差异。     

Abnormal cardiac histology in severe intrauterine growth retardation infants

Four infants with severe intrauterine growth retardation (IUGR) weighing less than 1000 g at birth developed heart failure and died in our unit, where heart failure of IUGR infants is the main reason of death in extremely low birth-weight infants. The causes of their heart failure are one of the main themes in current neonatal medicine. The subjects of this study were four small for gestational age infants; all died due to heart failure 5 to 10 days after birth. Microscopic specimens of hearts from autopsies were evaluated with respect to the following characteristics: thickness of myocardial fibers, maturation of nuclei, presence of dysgenesis or necrosis in myocardium, and amount of glycogen in the heart. Neither dysgenesis nor infarction of the heart was found but hypoplasia in myocardial fibers and decreased glycogen levels were observed. Maturation delay in myocytes' nuclei did not appear to be severe. We conclude that these infants' hearts failed to adapt to postnatal hemodynamic changes because of inadequate myocardial function and inadequate glycogen reserves.