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991.
以傅立叶频谱滤波为手段的振荡电位波形分离方法   总被引:1,自引:0,他引:1  
为克服传统方法(Calliper-square)和带通放大器在测量振荡电位(OPs)中的不足,应用计算机傅立叶频谱滤波技术,从ERG中分离出振荡电位波形。分离出的OPs能够摆脱a-波,b-波对它的影响而独立地表现出来,使得对OPs的测量变得直观、方便、准确,并把对ERG、OPs的研究,从时域分析扩展到频域分析。  相似文献   
992.
Liu X  Xu Y  Shen Y  Zhang H  Fu Y  Liu Z  Xu A 《Tissue antigens》2005,65(2):172-177
DPA1 gene is one of the human leukocyte antigen (HLA) class II genes and its promoter is highly polymorphic. From comparative studies among five southern Chinese populations, Jing, Li, Bai, Lahu, and Meizhou Han, we describe their single-nucleotide polymorphism (SNP)/haplotype frequency data of HLA-DPA1 gene promoter in this study. Within the 760-bp promoter region, we have identified 21 SNPs and nine possible haplotypes. Pair-wise comparisons show similar frequencies distribution of the HLA-DPA1 promoter haplotypes among Jing, Li, and Bai, whereas all pair-wise comparisons involved with Lahu or Meizhou Han and other ethnic groups show remarkable difference. The differences in frequencies of HLA-DPA1 promoter alleles may reveal different ethnic origins and demographic histories of the five populations. Our study may help distinguishing each of these populations by sequence variations of HLA-DPA1 promoter, which may be served as functional molecular markers for clinical and immunological studies involving the DPA1 locus.  相似文献   
993.
Di Y  Li J  Fang J  Xu Z  He X  Zhang F  Ling J  Li X  Xu D  Li L  Li YY  Huo K 《Journal of human genetics》2003,48(6):315-321
NTKL is an evolutionarily conserved kinase-like protein. The cell-cycle-dependent centrosomal localization of NTKL suggested that it was involved in centrosome-related cellular function. The mouse NTKL protein is highly homologous with human NTKL. A novel mouse protein was identified as an NTKL-binding protein (NTKL-BP1) by yeast two-hybrid screening, and the full-length cDNA was amplified based on the result of a sequence data analysis cloning strategy. The full-length cDNA sequence of the NTKL-BP1 gene consists of 2,537 bp, which encode 368 amino acids. A database search revealed that homologues of NTKL-BP1 exist in different organisms, including Arabidopsis thaliana, Drosophila melanogaster, Plasmodium falciparum, Geobacter metallireducens, Anopheles gambiae and human. It suggests that NTKL-BP1 is an evolutionarily conserved protein. The expression of NTKL-BP1 was observed in multiple normal mouse tissues. The interaction of the two proteins was confirmed by co-immunoprecipitation. Moreover, immunofluorescent staining indicated that NTKL and NTKL-BP1 were all localized in the cytoplasm.  相似文献   
994.
Dendrites and spines undergo dynamic changes in physiological and pathological conditions. Dendritic outgrowth has been observed in surviving neurons months after ischemia, which is associated with the functional compensation. It remains unclear how dendrites in surviving neurons are altered shortly after ischemia, which might reveal the mechanisms underlying neuronal survival. Using primary cortical cultures, we monitored the dendritic changes in individual neurons after oxygen-glucose deprivation (OGD). Two to four hours of OGD induced approximately 30–50% cell death in 24 h. However, the total dendritic length in surviving neurons was significantly increased after OGD with a peak at 6 h after re-oxygenation. The increase of dendritic length after OGD was mainly due to the sprouting rather than the extension of the dendrites. The dendritic outgrowth after 2 h of OGD was greater than that after 4 h of OGD. Application of NMDA receptor blocker MK-801 abolished OGD-induced dendritic outgrowth, whereas application of AMPA receptor antagonist CNQX had no significant effects. These results demonstrate a NMDA receptor-dependent dendritic plasticity shortly after OGD, which provides insights into the early response of surviving neurons after ischemia.  相似文献   
995.
目的:研究黄体激素释放激素(Luteinizinghormone releasinghormone,LHRH)在大鼠体内的药动学规律。方法:用氯胺T法将125I标记到LHRH分子上(放化纯度96.2%),14只SD大鼠随机分为大剂量、小剂量组,每组7只,分别肌肉注射125I LHRH(小剂量组0.5mg.kg,大剂量组1.00mg.kg),给药后在21个不同时间点逐一取各鼠尾动脉血做放射性测定。结果:大鼠试验结果显示,大剂量组t1/2平均为67.83±20.84h;小剂量组半衰期平均为64.68±22.90h。LHRH的药—时曲线符合二室模型,大剂量LHRH和小剂量LHRH的主要药动学指标差别不大。结论:LHRH在大鼠体内的消除模式为二室模型,为一级动力学消除。  相似文献   
996.
微波辐射免疫比浊法加速测定免疫球蛋白   总被引:1,自引:0,他引:1  
本文应用微波辐射免疫比浊法加速测定免疫球蛋白(IgG、IgA、IgM).结果表明:用本法测定的线性范围较宽:IgG从3.24~51.92/L;IgA从0.49~7.92g/L;IgM从0.36~5.75/L.批内、批间精密度(CV):IgG从44~7.4%;IgA从4.1~9.5%;IgM从4.0~8.8%.本法与传统免疫比浊法和进口试剂自动免疫比浊法(Monarch 2000)测定比较,其结果相关良好,r从0.950至0.996,P>0.05.本法的特点是操作简便、快速,可明显缩短抗原和抗体反应达到终点的时间.  相似文献   
997.
取不同年龄组自发性高血压鼠的胸主动脉,颈劝脉和基底动脉,用高效液相色谱-电化学检测仪测定其去甲肾上腺素含量,并取脑软膜血管作超微结构观察,结果显示:各组高血压鼠动有脉壁去甲肾上腺素含量均下降,颈内动脉更明显;脑血管内弹性膜部分断裂,平滑肌细胞有空不包变性等。  相似文献   
998.
在E极化、辐射电平1mw/cm2条件下,在40.68MHz~4GHz频段内6个频率点上,利用红外热图术观察了60只Wistar成年大白鼠,连续辐射1h后,体表及各部位体表温度变化。结果表明,体表温度与肛温变化有很好的一致性,并在1.5GHz有最大值。它表明在该频率下,实验鼠吸收射频能量最大,表现出明显的谐振吸引特性。  相似文献   
999.
A neoplastic proliferation of peripheral nerve sheath cells (Schwann cells, fibroblasts and perineurial cells) and ganglion cells in the colorectum may give rise to the mucosal or submucosal polyps. Depending upon the predominant cell types, these neurogenic polyps can be classified as schwannomas, granular cell tumours, neurofibromas, perineuriomas, mixed nerve sheath tumours, ganglioneuromas or paragangliomas. Morphologically, the neoplastic cells repeat or mimic the corresponding nerve sheath cells or neurons in terms of growth pattern, histology and immunoreactivity. They are uncommon, but the polyps can occur in any age group, although the vast majority of patients are adults. The polyps can be either solitary (most peripheral nerve sheath tumours) or multiple, especially if associated with systemic diseases (i.e. syndromes involving the peripheral nerve tissue). They are usually incidental findings or may be accompanied by gastrointestinal symptoms. Almost all colorectal neurogenic polyps are benign, and they rarely undergo malignant transformation unless they are part of a syndromatic manifestation. However, these polyps may cause a diagnostic problem during screening for colorectal cancer. An accurate diagnosis of these entities will help clinicians to make appropriate management decisions.  相似文献   
1000.
40日龄雄性Wistar大鼠21只,分为对照(C)组,腹腔内注射赋形剂和糖尿病(D)组,腹腔内注射链脲菌素(streptozotocin,STZ),55mg/kg体重,观察60天。结果表明,D组大鼠的睾丸、附睾、附睾尾重量显著低于C组(P<0.01);D组附睾尾精子计数显著少于C组(P<0.001)。ACE活性测定结果表明,D组睾丸和附睾尾组织ACE活性显著低于C组(P<0.05),而血清ACE显著高于C组(P<0.01),相关检验显示,附睾重量,附睾尾精子计数与附睾尾ACE水平呈显著正相关(P<0.01),与血清ACE呈显著负相关(P<0.05,P<0.01)。  相似文献   
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