颅内动脉夹层的发病机制、影像学特点和自然病程

颅内动脉夹层相比颅外动脉夹层较少见,且临床表现缺乏特异性,既可以表现为缺血性 事件,也可以表现为出血性事件,多发生于年轻人。由于夹层发生部位、形成时机以及病变严重程度 不同,临床表现各种各样,影像学对于确诊动脉夹层至关重要。颅内动脉夹层易复发,且死亡率较高, 除无症状或症状轻微的患者给予保守治疗或随访观察外,对于症状较重或进展性动脉夹层患者,应 给予积极治疗,包括血管内治疗。     

猪丘脑、小脑和延髓内Leptin长形受体mRNA的分布定位

目的 :研究猪丘脑、小脑和延髓内leptin长形受体 (longformleptinreceptor,Ob Rb)mRNA的分布定位 ,比较长白猪和眉山猪上述脑区内Ob RbmRNA分布的差异。方法 :原位杂交法。结果 :在丘脑内 ,Ob RbmRNA标记神经元几乎见于所有核团 ,在中线核、丘脑室旁核和丘脑前核内出现大量的Ob RbmRNA标记神经元 ,其余核团内Ob RbmRNA标记神经元分布较少。在小脑皮质三层中均有Ob RbmRNA标记神经元 ,以梨状神经元层和颗粒层分布较密集。在延髓下橄榄核、孤束核、迷走神经背核和舌下神经核有Ob RbmRNA标记神经元出现。结论 :猪丘脑、小脑和延髓内均有Ob RbmRNA分布 ,其分布定位在长白猪与眉山猪未见明显的差异。     

白血病小鼠经不同预处理方案的骨髓移植后移植细胞归巢特点

本研究构建白血病小鼠模型,通过这个模型探讨经不同预处理方案骨髓移植后骨髓细胞的归巢特点。采用非清髓性和放、化疗两种清髓性预处理方案。非清髓性预处理方案为5 Gy 60Coγ射线全身照射(A组),放疗清髓性方案为9 Gy 60Coγ射线全身照射(B组),化疗清髓性预处理方案为大剂量化疗(C组)。经上述预处理方案处理的白血病小鼠分别在骨髓移植后24、48、72、96 h检测受鼠外周血、骨髓和脾中有核细胞数和供鼠阳性细胞数,计算供鼠骨髓细胞在受鼠骨髓和脾的归巢率。结果显示:供鼠骨髓细胞在受鼠体内的表现分别为:A组是先归巢再出巢;B组是归巢,出巢,再归巢;C组同B组,但是在脾中的归巢比在骨髓中延迟。比较3组的归巢率显示,供鼠骨髓细胞在骨髓的归巢率在A组早期比B组和C组高,随着时间的推移,部分细胞出巢,归巢率迅速下降至各组中最低,为(0.90±0.09)%(P<0.05);B、C两组早期归巢率较低,随着时间推移,细胞出巢后再次归巢,第4天的归巢率迅速上升,B组升至最高,为(2.17±0.26)%(P<0.05);在脾中的归巢率与骨髓中相似,C组仍有延迟。结论:经非清髓性预处理的白血病小鼠骨髓移植术后,早期归巢率较高,72 h后明显减低;经放疗清髓性预处理小鼠,其早期归巢率较低,72 h后明显增高;经化疗清髓性预处理小鼠,早期和72 h后归巢率无明显变化,归巢率介于其他两组之间。     

表达SARS冠状病毒受体人ACE2转基因小鼠的建立

目的:建立表达SARS冠状病毒的功能性受体人ACE2的转基因小鼠.方法:克隆人2型血管紧张素转换酶(hACE2)的cDNA,连入PCAGGS构建转基因表达载体,以显微注射的方法将5.6 kb的转基因片段引入小鼠的受精卵.采用PCR、Southern印迹、RT-PCR、Western印迹、免疫荧光染色的方法对转基因小鼠进行鉴定.结果与结论:获得了在小鼠肺组织中表达有SARS病毒功能性受体hACE2的两个转基因小鼠系,证明了SARS病毒的S蛋白能很好地和转基因小鼠肺组织中表达的hACE2受体结合,这将为SARS的研究提供一种良好的感染动物模型.     

医学验光和常规验光的对比研究

目的:探讨科学、规范的验光方法。方法:随机抽取近视患者190例(380眼),年龄14～35岁,进行医学验光与常规验光的对比。结果:(1)球镜柱镜度数的差异:差异均在0.50D～0.75D范围最常见,与其它各组比较有明显的差异。(2)柱镜的轴位的差异:差异在6～10度范围最常见,与其它各组比较有近两倍以上的差异。结论:临床验光应科学规范,应广泛推广医学验光。     

PreS_1和HBV-DNA与HBV-M相关性分析

目的:探讨乙肝病毒前S1抗原(PreS1Ag)在诊断慢性乙型病毒性肝炎病毒复制中的作用。方法:收集慢性乙型病毒性肝炎患者500例,其中HBV-DNA阳性400例(拷贝数>500/ml),按HBV-DNA含量由低到高分8组;其余为HBV-DNA阴性对照100例。检测乙肝血清标志物(HBsAg、HBeAg、HBeAb)与PreS1Ag。结果:(1)HBV-DNA<1×106/ml,PreS1Ag的阳性率比HBeAg高,两者比较差异有显著性(P<0.05);HBV-DNA1×106/ml以上,PreS1Ag与HBeAg相比差异无显著性(P>0.05)。(2)HBV-DNA<1×105/ml,PreS1Ag阳性率随着HBV-DNA含量增加而增加,不同组间的PreS1Ag阳性率相比差异有显著性(P<0.05)。(3)HBV-DNA<1×107/ml,HBeAg的阳性率随着HBV-DNA含量增加而增加,不同组间的HBeAg阳性率相比差异有显著性(P<0.05)。(4)HBV-DNA<1×106/ml,HBeAb有较高的阳性率,并随着HBV-DNA含量的增加而逐渐下降,不同组间的HBeAb阳性率相比差异有显著性(P<0.05)。(5)以HBV-DNA检测结果为金标准,HBeAg的灵敏度为68.5%(274/400),阴性预示值为43.2%(96/222),检测有效率为64.8%(324/500);均低于PreS1Ag的灵敏度90.0%(360/400),阴性预示值55.6%(50/90),检测有效率82.0%(410/500)。结论:PreS1Ag比HBeAg较准确的反映乙肝病毒的复制情况,是“乙肝五项”有益的必要补充。     

牛磺酸对培养乳鼠心肌细胞胞浆游离钙浓度的影响

在培养的单个SD乳鼠心肌细胞,观察了牛磺酸对KCl, 去甲肾上腺素(NE)和毒毛花苷G引起的胞浆游离Ca^２＋浓度(［Ca^２＋］_i)变化的影响. 当细胞外CaCl₂浓度为1.3 mmol·L^-１时, 牛磺酸10, 20 mmol·L^-１不影响心肌细胞静息［Ca^２＋］_i; 但能浓度依赖性地抑制35 mmol·L^-１ KCl和1 μmol·L^-１毒毛花苷G升高［Ca^２＋］_i的作用.10 μmol·L^-１ NE在含Ca^２＋的缓冲液中能引起双相的［Ca^２＋］_i变化, 即快速升高相和持续升高相.牛磺酸20 mmol·L^-１能抑制NE引起的［Ca^２＋］_i持续升高, 而对快速升高相无显著影响. 在无 Ca^２＋ 的缓冲液中, 牛磺酸不影响NE升高［Ca^２＋］_i的作用. 结果提示牛磺酸可能通过减少心肌细胞电压依赖性Ca^２＋内流和Na⁺/Ca^２＋交换而抑制KCl, NE和毒毛花苷G引起的［Ca^２＋］_i升高.     

Prevalence of methylphenidate use and change over a two-year period: a nationwide study of 2- to 11-year-old Canadian children

OBJECTIVE: To provide age- and sex-specific estimates of methylphenidate use and to determine use changes over a 2-year period. STUDY DESIGN: We examined the first and second data collection cycles of the National Longitudinal Survey of Children and Youth, a Canadian household survey of children. Participants were children aged 2 years to 11 years at both the first and second cycles whose mothers responded; thus, 16,798 (13,059) children were assessed for the first (second) cycle. Logit modeling was used to estimate prevalence of methylphenidate use, to determine sex and age effects on prevalence, and to examine use changes from cycle 1 to 2. RESULTS: Methylphenidate prevalence ranged from 0.09% to 3.89% across 2- to 11-year old children from the first cycle. Boys were 4.6 times more likely than girls to consume methylphenidate. Use was >4 times greater among 6- to 7-year-old children compared with 4- to 5-year-old children and almost 2 times greater among 8- to 9-year-old children compared with 6- to 7-year-old children. Methylphenidate prevalence increased by 36% from cycle 1 to 2. CONCLUSIONS: Methylphenidate prevalence was relatively low. Boys and school-age children had higher rates of methylphenidate use, and use among 2- to 11-year-old children appeared to be increasing over time.     

Efficacy of intravenous zoledronic acid in the prevention and treatment of osteoporosis: a meta-analysis

ObjectiveTo compare the effect of zoledronic acid in treatment and prevention of osteoporosis with placebo.MethodsRandom control trials regarding zoledronic acid in treatment of osteoporosis were retrieved by selecting Medline, EMbase and Pubmed databases till April 2012. The RevMan software was used for all of the statistical analysis.ResultsA total of 9 trials were included in this meta-analysis. The pooled effect showed that zoledronic acid could increase the bone mineral density by 2.98 times compared with placebo, and reduce the rate of fracture in patients by 32%. The results should the zoledronic acid intervention had significantly less serious adverse events than controls, and the odds ratio was 0.81 (0.76–0.87). The longer term intervention, more than 12 months intervention, could gain a better prevention effect for osteoporosis (OR, 95% CI for BMD was 3.35, 2.77–3.92; for fracture was 0.67, 0.54–0.82).ConclusionsThis present study shows that zoledronic acid could be effective approach in the prevention of osteoporosis, and could increase the bone mineral density and reduce the risk of facture.