Mechanisms governing the differentiation of a serotonergic phenotype in culture

The blood–brain barrier prevents the entry of many potentially therapeutic peptide drugs to the brain. Glycosylation has shown potential as a methodology for improving delivery to the CNS. Previous studies have shown improved bioavailability and improved centrally mediated analgesia of glycosylated opioids. In this study we investigate the effect of glycosylation on the cyclic opioid peptide [ -Cys^2,5,Ser⁶,Gly⁷] enkephalin. The peptide was glycosylated on the Ser⁶ via an O-linkage with various sugar moieties and alignments. The peptides were then investigated for receptor binding, physiochemical attributes, in situ brain uptake in female Sprague–Dawley rats and antinociception in male ICR mice. Glycosylation resulted in a slight decrease in affinity to the δ-opioid receptor, and mixed effect on binding to the μ-opioid receptor. There was a significant decrease in lipophilicity resulting from glycosylation and a slight reduction in binding to bovine serum albumin. In situ perfusion showed that brain uptake was improved by up to 98% for several of the glycosylated peptides, and the nociceptive profiles of the peptides, in general, followed the rank order of peptide entry to the brain with up to a 39-fold increase in A.U.C.     

Geodesics without conjugate points and curvatures at infinity

We study the asymptotic behavior of curvature and prove that the integral of curvature along a geodesic without conjugate points is nonpositive and some generalizations of Myers theorem and Cohn-Vossen's theorem. Some applications are also given.     

共轭亚油酸对肥胖大鼠PPARγ基因表达及血清瘦素水平的影响

目的　研究不同剂量共轭亚油酸 (CLA)对饮食诱导肥胖大鼠PPARγ基因、瘦素、血糖、血脂的影响。方法　选用雄性Wistar大鼠 ,随机分为对照组、高脂组、高脂 +CLA组 (每 10 0g饲料含CLA分别为 0 75g、1 5 0g、3 0 0g) ,于第 12周末处死动物 ,计算脂 体比 ,测定大鼠血糖、血脂及瘦素水平 ,并应用RT PCR的方法检测大鼠白色脂肪组织过氧化物酶体增殖物激活受体γ(PPARγ)的表达水平。结果　CLA可降低肥胖大鼠血糖、甘油三酯 (TG)、总胆固醇 (TC)及瘦素水平 ,增加脂肪组织PPARγmRNA的表达水平。结论　CLA可降低肥胖大鼠血糖、血脂 ,并可通过激活PPARγ下调瘦素水平 ,有改善肥胖大鼠的瘦素抵抗作用。     

微机极谱法同步测定血中铜 锌 铁的方法学探讨

探讨Cu2 + 、Zn2 + 和Fe2 + 在乙二胺—三乙醇胺体系中的极谱联合测定方法 ,同时测定了 75 8例健康受试者中铜、锌和铁离子浓度。Cu2 + 、Zn2 + 和Fe2 + 在 0～ 4 g/L范围内线性较好 ,其检测极线分别是 7.8× 10 -5、5 .9× 10 -5和 8.2× 10 -6g/L ;样本分析的SD(CV)分别是 0 0 5 (4 5 6 % ) ,0 0 5 (4 5 9% )和 0 0 6 (4 5 1% ) ;回收率 (均值 )分别是 95 31%～ 10 2 4 8% (98 2 3% ) ,96 71%～ 10 1 34% (99 2 8% )和 98 16 %～ 10 3 95 %(10 1 92 % ) ;测定峰电位分别是 - 0 5 8V ,- 0 96和 - 1 35V。该方法与原子吸收分光光度法测定结果之间无统计学差异。     

Comparison Study on Clinical and Neuropathological Characteristics of Hamsters Inoculated With Scraple Strain 263K in Different Challenging Pathways

OBJECTIVE: To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.c.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. METHODS: Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrP(Sc) deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immnunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. RESULTS: The animals inoculated in i.m. and i.p. ways with crude PrP(Sc) extracts showed clinical signs at the average incubation of 69.2 +/- 2.8 and 65.5 +/- 3.9 days. Inoculation in i.c. and intracardiac ways with fine PrP(Sc) extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g. way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrP(Sc) deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. CONCLUSION: Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrP(Sc). The neuropathological changes and PrP(Sc) deposits seem to be related with regions and inoculating pathways.     

肺、食管手术切口感染危险因素的研究

目的　本研究旨在探讨肺、食管手术切口感染的危险因素 ,为控制切口感染提供依据。方法　前瞻性纳入90 2例肺、食管择期手术病人 ,观察切口感染及相关因素 ,并对年龄、性别、手术时间、术式等 15项变量与切口感染的关系 ,分别进行单因素和多因素的logistic回归分析。结果　肺、食管手术切口感染率为 3.6 6 %。单因素分析发现术后血白细胞计数、手术时间、术式中的多切口手术、失血量、术后诊断为食管上段癌与切口感染相关 (P <0 .0 5 ) ,多因素分析筛选出 3个切口感染的相关因素 :术后血白细胞计数、手术时间、多切口手术 (P <0 .0 5 )。结论　肺、食管手术后血白细胞计数、手术时间、采用多切口手术与切口感染有着密切联系 ,手术后血白细胞计数持续升高应注意切口感染的发生。     

应用HACCP原则在餐饮业中的作用

目的：在餐饮业中应用HACCP管理系统，保证食品质量安全，预防食物中毒发生。方法：分析1995∽1999年日照市5年内12家单位食物中毒发生的特点，找出存在的危害环节，制订控制措施，成立以经理、厨师、采购员、服务员领班为成员的领导小组，通过监督部门培训指导，负责实施HACCP计划。结果：自2000年，在实施HACCP管理单位中，未再发生食物中毒。结论：在餐饮业应用HACCP管理是有效的。将HACCP原则作为执行标准是必要的。     

内镜下摘除结肠息肉126例临床体会

目的　探讨如何提高内镜下摘除结肠息肉的成功率及降低并发症的发生率。方法　使用OLYMPUSEVIS2 0 0CF - 2 0 0L电子结肠镜及PSD - 2高频电灼器 ,SD - 5U - 1 6U - 1圈套器进行结肠息肉摘除。结果　摘除了 12 6例共 198颗结肠息肉 ,成功率 10 0 %。结论　严格遵守结肠息肉摘除操作规程和注意事项 ,能提高成功率并可减少并发症的发生     

正常幼儿语法发育的影响因素研究

【目的】了解影响幼儿语法发育的有关因素．为促进幼儿语言发育提供依据。【方法】采用现况定量研究方法。用多阶段分层不等比例抽样方法在北京4个城区抽取样本。用“中文早期语言与沟通发展量表”及个人背景问卷，对北京城区1056名16～30个月正常幼儿母亲或日间照顾人进行面对面问卷调查。运用Z评分法对幼儿语法粗分进行标准化．再用单因素和多重回归分析方法探讨影响幼儿语法发育的因素。【结果】凋查地区16～30个月龄正常幼儿平均语法表达结构得分由16个月时的6分增加到30个月时的84分，占总分的83％。单因素分析和多重回归分析结果显示，父亲受教育程度、父亲月收入、幼儿性格外向是幼儿语法发育的有利因素；幼儿开始说话月龄与幼儿语法发育得分Z评分呈负相关。【结论】家庭社会经济状况是影响小儿语法发育的重要因素。保健人员应重视幼儿语言发育，教育幼儿父母注意与儿童沟通．加强对儿童的早期教育，为儿童创造良好的早期语言环境。     

乙型肝炎住院病人抑郁心理的危险因素研究

目的探讨乙型肝炎住院病人抑郁心理的危险因素。方法采用CES—D量表对369名乙型肝炎住院病人进行心理评价。以肯定抑郁心理的病人作为病例组，以无抑郁心理的病人作为对照组进行病例对照研究，采集2组病人的病情资料，同时调查了艾森克个性问卷以及病人的认知、行为、态度等情况。作多元Logistic回归分析，确定主要危险因素。结果乙肝住院病人中肯定抑郁心理的占43．36％，其抑郁心理主要受到病情复发次数、周围人的疏远、对治疗的信心以及EPQ—N(情绪稳定性)等4个因素影响。结论加强公众健康教育，增强病人信心，控制病情反复是预防病人抑郁心理的有效手段。