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991.
992.
目的:测定原发性高血压患者外周血中血清一氧化氮(NO)、一氧化氮合酶(NOS)及其亚型水平,探讨NO/NOS系统参与血压调节的可能机制.方法:原发性高血压患者135例,正常对照组35例.采用化学法检测所有病例外周血的一氧化氮(NO)、总NOS、诱导型一氧化氮合酶(iNOS)和结构型一氧化氮合酶(cNOS)水平并作统计学分析.结果:高血压组NO、NOS、iNOS和cNOS水平均低于正常对照组,且差异具有显著性意义(分别为:P<0.05,P<0.01,P<0.01,P<0.01);iNOS/cNOS比值与正常对照组相比无显著差异(P>0.05);对照组和高血压组的NOS浓度与iNOS和cNOS浓度均呈显著正相关;高血压组的cNOS水平与iNOS水平呈显著负相关.结论:高血压患者NO、NOS及其亚型浓度值可以作为临床评估高血压的参考指标;iNOS在正常人体内有表达;在高血压情况下,机体有通过增加iNOS的表达来弥补cNOS水平的病理性降低、调控NOS总体水平从而调节和平衡血压的趋势. 相似文献
993.
抗肠出血性大肠杆菌O157:H7 EspA单克隆抗体的制备及其特性鉴定 总被引:1,自引:2,他引:1
目的:制备抗肠出血性大肠杆菌O157:H7EspA单克隆抗体(mAb)。方法:以重组EspA蛋白为免疫原免疫BALB/c小鼠,运用杂交瘤技术并且联合间接ELISA筛选只针对EspA的杂交瘤细胞株。以Ig类与亚类鉴定试剂盒鉴定mAb的Ig亚类,ELISA、Western blot及免疫荧光技术鉴定抗体的免疫学特性。结果:获得3株稳定分泌抗EspA杂交瘤细胞的mAb,Ig亚型分别为IgG1κ型、IgG2aκ型、IgG2bκ型。Western blot和免疫荧光分析表明,3株杂交瘤细胞制备的mAb腹水都能特异地结合重组EspA蛋白和识别O157:H7的EspA成分。结论:成功地制备了抗肠出血性大肠杆菌O157:H7EspA的mAb,并证明了该mAb的生物学活性,为深入研究肠出血性大肠杆菌O157:H7的致病机制提供新的手段。 相似文献
994.
顺行交锁髓内钉治疗肱骨骨折 总被引:1,自引:0,他引:1
目的探讨顺行交锁髓内钉治疗肱骨骨折的手术要点和治疗效果。方法回顾性分析2003年10月~2005年10月23例顺行肱骨交锁髓内钉治疗肱骨干中上段骨折。结果全部病例随访6个月~1年3个月,平均11个月。所有病例均骨性愈合,平均临床愈合时间为2.4个月。所有关节活动度均可。结论顺行交锁髓内钉治疗肱骨中段或中上段骨折,效果良好。 相似文献
995.
996.
997.
We present a mathematical model for pre-fusion interaction between an influenza virus and a healthy cell. Our model describes the role played by hemagglutinin (HA) protein clusters in bringing the viral membrane into close contact with the host cell membrane as a first step of the fusion process between the two membranes. The viral membrane is modelled as a lipid bilayer with bending rigidity. Using the calculus of variations, we compute the deformation of the viral membrane under the influence of HA protein clusters. Our numerical results support the hypothesis of dimple formation in the fusion site proposed in the literature. The asymmetric nature of the protein molecules due to various reasons such as tilting is the primary cause for the dimple formation. We discuss the effects of spontaneous curvature, the protein cluster radius, fusion-site size and the bending moment exerted by the protein cluster. We also examine the effects of membrane tension and the presence of a host cell on the dimple shape. Our results support previous experimental observations. 相似文献
998.
目的:了解仫佬族学生超声骨密度的变化规律及其影响因素.方法:按年龄进行分组,以1岁作为1个年龄段.采用定量超声技术(QUS)测定长居广西河池市罗城县四把镇的956名(男465,女491)7~15岁正常儿童的跟骨QUS参数超声振幅衰减系数(BUA),同时测量受检者身高和体质量.结果:7~15岁仫佬族男、女学生BUA值随年龄的增长而增加.男、女生各年龄段的BUA值差异无统计学意义,同性别相邻的2个年龄组间无统计学意义,同年龄不同性别间亦无统计学意义.7~15岁男、女生BUA与年龄、身高、体质量和BMI均呈正相关(P<0.01),年龄、身高和体质量是超声骨密度参数的主要决定因素.结论:年龄、身高和体质量是影响儿童青少年骨密度的重要因素;本研究获得仫佬族学生定量超声BUA正常参考值,为仫佬族儿童少年骨质疏松症诊疗提供依据,为指导和改善仫佬族学生钙营养提供依据. 相似文献
999.
Mariacristina Scoto Thomas Cullup Sebahattin Cirak Shu Yau Adnan Y Manzur Lucy Feng Thomas S Jacques Glenn Anderson Stephen Abbs Caroline Sewry Heinz Jungbluth Francesco Muntoni 《European journal of human genetics : EJHG》2013,21(11):1249-1252
Recessive nebulin (NEB) mutations are a common cause of nemaline myopathy (NM), typically characterized by generalized weakness of early-onset and nemaline rods on muscle biopsy. Exceptional adult cases with additional cores and an isolated distal weakness have been reported. The large NEB gene with 183 exons has been an obstacle for the genetic work-up. Here we report a childhood-onset case with distal weakness and a core-rod myopathy, associated with recessive NEB mutations identified by next generation sequencing (NGS). This 6-year-old boy presented with a history of gross-motor difficulties following a normal early development. He had distal leg weakness with bilateral foot drop, as well as axial muscle weakness, scoliosis and spinal rigidity; additionally he required nocturnal respiratory support. Muscle magnetic resonance (MR) imaging showed distal involvement in the medial and anterior compartment of the lower leg. A muscle biopsy featured both rods and cores. Initial targeted testing identified a heterozygous Nebulin exon 55 deletion. Further analysis using NGS revealed a frameshifting 4 bp duplication, c.24372_24375dup (P.Val8126fs), on the opposite allele. This case illustrates that NEB mutations can cause childhood onset distal NM, with additional cores on muscle biopsy and proves the diagnostic utility of NGS for myopathies, particularly when large genes are implicated. 相似文献
1000.
Rong-Hua Yang Ju-Lin Xie Bin Shu Xu-Sheng Liu Xiao-Dong Chen Shu-Bin Ruan Shao-Hai Qi 《International journal of clinical and experimental pathology》2013,6(11):2529-2534
The management of burns and injuries using novel treatment strategies involving epidermal stem cells (ESC) requires a better understanding of the biology of these cells, in particular, their isolation and the maintenance of their unique characteristics in culture. The purpose of this study was to describe an improved method for isolating putative ESC from fetal rat skin and to maintain them long term in culture. Single ESC suspensions were obtained from fetal rat skin by enzyme digestion containing 0.5% neutral protease. The target cells were harvested by rapid adherence on type IV collagen plates and were cultured in complex DMEM. After primary isolation, cells were continuously cultured in K-serum free medium. After reaching 70-80% confluence, the cells were digested with 0.25% trypsin at 37°C for 5-10 minutes, and passaged at a ratio of 1:2. The cultured ESC showed good growth, resulting in cell viability of over 98%. Four days later, clones containing 100-200 cells were detected, showing cobblestone-like characteristics. The rapidly adherent cells were positive for keratin 15, 19 and P63. Eighty three percent of cells expressed β1 integrin. The growth-curve showed that the rapidly adherent cells were in the exponential growth phase. The protocol described in this paper provides a simplified and effective method to isolate and maintain long-term culture of epidermal stem cells from fetal rat skin. This method should be valuable for isolating and studying ESC from various transgenic rat lines that are currently available. 相似文献