The incomplete inactivation of Fgf8 in the limb ectoderm affects the morphogenesis of the anterior autopod through BMP-mediated cell death.

Here we analyze limb development after the conditional inactivation of Fgf8 from the epiblast, using the previously described MORE (Mox2Cre) line. This line drives variable mosaic recombination of a floxed Fgf8 allele, resulting in a small proportion of AER cells that maintain Fgf8 expression. The phenotype of Mox2Cre;Fgf8 limbs is most similar to that of Msx2Cre;Fgf8 forelimbs, indicating that a small but durable expression of FGF8 is equivalent to an early normal, but transitory, expression. This functional equivalence likely relies on the subsequent Fgf4 upregulation that buffers the differences in the pattern of Fgf8 expression between the two conditional mutants. The molecular analysis of Mox2Cre;Fgf8 limbs shows that, despite Fgf4 upregulation, they develop under reduced FGF signaling. These limbs also exhibit an abnormal area of cell death at the anterior forelimb autopod, overlapping with an ectopic domain of Bmp7 expression, which can explain the abnormal morphogenesis of the anterior autopod.     

模式翻转视觉诱发电位快速提取的可行性再研究

目的把模式翻转视觉诱发电位快速提取法应用于视神经病变的病人,探讨其临床应用价值。方法应用Galileo视觉诱发电位检测系统对30例正常健康人和17例视神经疾病病人分别进行全视野的PRVEP检测熏每一结果重复检测3次。所得结果应用少次提取法进行处理而得VEP波形。然后将正常对照组3次重复结果两两间分别进行配对t检验,探讨其可重性,并计算出正常值范围,最后参照正常值,分析视神经疾病组的检测结果。结果3次重复结果两两间配对t检验,得P1=0.425>0.05,P2=0.179>0.05,P3=0.110>0.05;参照本研究得出的正常值范围,对病人组的检测结果进行分析,得出这种少次提取法对视神经疾病检测的敏感度90.0%(18/20),特异度92.5%(13/14),准确度91.1%(31/34)。结论用这种少次提取法提取PRVEP,可重性好,稳定可靠。很有临床应用价值。     

The human motion onset VEP as a function of stimulation area for foveal and peripheral vision

We studied amplitude of the wave N200 of the motion-onset VEP by varying the side length of a square stimulation field between 0.5 and 7 degrees. A significant increase in amplitude was obtained between 0.5 and 1 degree of side length in central stimulation and between 0.5 and 5 degrees in 10-degree peripheral stimulation. Variations of spatial frequency between 0.34 and 6.8 c/deg did not modify the amplitude size, ie, no tuning effect could be found. The results of simultaneous and separate stimulation of foveal and parafoveal regions support the observation that the stimulation field size is a minor influence. Features of motion-sensitive cortical neurons, such as those found in monkeys, could account for this behavior.     

Effect of low dose radiation on subpopulations of lymphocytes and T cell subsets in mice

<正> The effect of radiation on lymphocyte subpopulations and T cell subsets of peripheral blood was studied in mice after X- and y-irradiation.lt was found that (1) there were neither marked changes in the percentage and absolute number of acid alpha-naphthol acetyl esterase "positive(ANAE + )cells of different granular patterns, nor significant lowering of the T11/Ts ratio after single whole body X-irradiation in the dose range of 25-250 mGy with a dose rate of 12.5mGy/min. At the same time no significant changes were found at different time intervals after irradiation. After continuous low level irradiation with 60Co γ-rays with a dose rate of 5.4 mGy/6h.d,the ANAE grauular pattern of lymphocytes showed no significant changes with cumulative doses of 32.4 -520 mGy. (3)There was no decrease in the "splenocyte Ts index in Kunming mice after low dose X-irradiation. The results suggest that the stimulatory effect of low dose radiation on the PFC reaction can not be explained on the basis of a decrease in num     

利福霉素类抗生素的晶型与血（尿）药浓度

目的：探讨利福霉素类抗生素的衍生物（利福平,利福定,利福喷丁）的晶型与血（尿）药浓度的关系。方法：通过正常人空腹口服各不同型晶粉,定时收集血、尿标本,用杯碟法测定血、尿药含量。结果：同一药物的不同晶型粉,显示出各自不同的结构图形、溶解度及生物有效度的特性。结论：凡是稳定的晶型均具恒定的结构及生物有效度,利福霉素类药物的含水量,对其晶型的稳定性至关重要,干燥失重,不是越低越好。     

快速检测神经元放电串中优势模式

目的 :新建一个“优势模式 (favoredpattern ,FP)”快速检测法 ,用以检测不同神经元放电串中之FP ,并检验其效果。方法 :在原有的“改进的FP检测法”的基础上 ,采用数种措施实现快速检测 ,并用多个指标检验其检测效果。结果 :(1)具有 3种不同程度变动的各种模拟FP的检出阈均为 2 ,表明该法敏感 ;(2 )自发放电串中各个FP重复出现时 ,其全长和所含不同放电间隔长度之变异系数分别为 5 %和 17% ,均小于检测所规定的容差 ,表明该法可靠 ;(3)自发放电串中FP长时间稳定地存在 ,而诱发放电串中不同FP的总数随放电率的变化而增减 ;(4 )所有被检测的放电串 (总数 92 )都能检测到FP ,检测一个 12 0 0～ 15 0 0个动作电位的放电串中的FP仅需 2～ 3s。结论 :新建立的“快速FP检测法”可能是研究神经信息编码的一个很有用的手段     

中比两国居民营养状况及膳食结构比较

目的 :比较中比两国居民饮食营养状况的异同及中国人群膳食结构变化趋势。方法 :称重和记帐膳食调查。结果 :两国人均日总热能摄入量相近 ,中国人均蛋白质、维生素A(VitA)、核黄素 (VitB1)、钙 (Ca)等摄入量则明显低于比利时 ;中国人均动物性食品摄入量随经济收入的增高而增多。结论 :中国居民主要营养素摄入能满足机体需要 ,食物结构趋向优化 ,但要进一步促进豆类和乳类食品的生产和消费。     

医学高职高专教育英语教学模式研究

目的 :探讨适合医学高职高专教育的英语教学模式。方法 :通过对 10个医疗单位和开封医专往届毕业生调查 ,英语在实际工作中的运用 ,并对其调查结果用卡氏检验法进行统计。结论 :现有的医学高职高专教育的英语教学模式不适合医学高职高专教育的培养目标。结果 :医学高职高专教育英语教学模式应把基础英语和专业英语放到同等重要位置 ,旨在培养学生在实际工作中运用语言的能力     

基因表达谱芯片在胰腺癌相关基因筛选中的应用研究

目的：探讨基因表达谱芯片技术在高通量筛查肿瘤相关基因群及研究胰腺癌分子病理变化中的应用价值。方法：应用含有４０９６条人类全长基因的ｃＮＤＡ表达谱芯片,对３例临床切除的胰腺癌及正常胰腺标本的基因表达谱进行分析。结果：在３例胰腺癌和正常胰腺组织中均有差异表达的基因３９８条,其中新基因２８９条,老基因１０９条。从老基因中筛选出有显著表达差异基因３７条,其中在胰腺癌组织中上调基因２０条,下调基因１７条。结