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991.
T. Y. Wu X. Q. Wang C. Y. Wei H. W. Cheng X. Z. Wang Y. Li Ge-Dong H. N. Zhao P. Young G. L. Li Z. G. Wang 《Comparative clinical pathology》2005,14(1):25-35
Tibetans form a population which has resided on the Qinghai–Tibetan plateau for thousands of years, and are reported to have less hemoglobin than Han Chinese lowlanders who have migrated to the plateau. However, for various altitudes, detailed comparisons of hemoglobin in the two ethnic groups has not been reported. We investigated the hypothesis that the effects of altitude, age, and gender on hemoglobin concentration would differ between Han and Tibetan residents of the plateau. Hematological parameters for both genders were determined in healthy Tibetan adults (n=3,000) and children (n=332), and healthy Han Chinese adults (n=2,612) and children (n=275), aged 5–60 years living at four different altitudes (mean altitude of 2,664, 3,813, 4,525, and 5,200 m). Hemoglobin values increased with altitude for all ages in both ethnic groups and in both genders. The gain in hemoglobin with altitude had the rank order: Han males > Han females > Tibetan males and females. Even before puberty, Han children had more hemoglobin than Tibetan children. An effect of age on hemoglobin was seen at the time of puberty in men, but not in women. A positive correlation was found between hemoglobin concentration and age in adult Han males and females, but not in Tibetan males, and only at the higher altitudes, in Tibetan females. In both Tibetans and Hans, males had higher hemoglobin values than females at each altitude, but the gender differences increased with altitude in Han, whereas it either decreased or did not change in Tibetans. Examination of hemoglobin levels by histogram showed non-Gaussian distributions: Tibetan men and women had skewing to higher values, whereas Han men and women had skewing in the opposite direction. We conclude that increasing age and the effect of gender in Tibetans are associated with different hemoglobin responses to altitude than in Han, and we speculate that genetic influences may be involved. 相似文献
992.
A novel method for making "tissue" microarrays from small numbers of suspension cells. 总被引:1,自引:0,他引:1
Kelli Montgomery Shuchun Zhao Matt van de Rijn Yasodha Natkunam 《Applied immunohistochemistry & molecular morphology》2005,13(1):80-84
Tissue microarrays (TMAs) are a highly efficient method for large-scale protein expression studies. To date most TMAs have been constructed using paraffin-embedded specimens. The authors developed a method that allows construction of TMAs from small numbers of cells in suspension. Spun pellets of 1x10 to 1x10 cells are directly processed and embedded in paraffin in an Eppendorf tube. Cylindrical cores of 0.6 mm are taken from these tubes and embedded in a recipient paraffin block to create a TMA. This relatively simple but versatile method enables very small numbers of cells in suspension to be analyzed using the TMA technology and allows for the study of hematolymphoid and related disorders of the blood and bone marrow for which solid tissue samples cannot be readily obtained. With the increasing trend toward obtaining small samples for screening and diagnostic purposes, this method provides a means to manipulate small volume samples for high-throughput immunohistochemical analysis. This method is also amenable for use for cultured cells. 相似文献
993.
OBJECTIVE: Propylthiouracil (PTU) could induce MPO-ANCA-positive vasculitis. The aim of this study was to compare the IgG subclass distribution and avidity of MPO-ANCA in sera from patients with primary ANCA-associated vasculitis (AASV) and PTU-induced vasculitis. METHODS: Nineteen patients with primary AASV with MPO-ANCA and thirteen patients with PTU-induced vasculitis were enrolled in the current study. Sera in both active phase and remission were collected. Anti-MPO IgG subclasses were detected by antigen specific ELISAs using specific monoclonal antibodies as second antibodies, and MPO-ANCA avidity was assessed by antigen-inhibition ELISAs. RESULTS: In primary AASV, all four anti-MPO IgG subclasses could be detected in active phase with IgG1 (100%), IgG2 (73.7%), IgG3 (63.2%) and IgG4 (94.7%), and in remission, IgG1 and IgG4 subclasses in most patients remained positive. However, in PTU-induced vasculitis, anti-MPO IgG3 subclass could not be detected, the anti-MPO IgG subclasses in active phase were IgG1 (100%), IgG2 (61.5%) and IgG4 (46.2%). Furthermore, five out of the six patients (88.8%) with PTU-induced vasculitis with positive IgG4 subclass in active phase turned to negative in remission, however, only eight out of the fourteen patients (57.1%) with primary AASV turned to negative. The median avidity constant of MPO-ANCA was 56 (8.96 to >140) x 10(7) mol/l for patients with primary AASV and 0.7 (<0.28 to >140) x 10(7) mol/l for patients with PTU-induced vasculitis respectively. Furthermore, the relative levels of MPO-ANCA avidity were associated with elevation of ESR in primary AASV and were associated with BVAS scores in patients with PTU-induced vasculitis, respectively. CONCLUSION: MPO-ANCA IgG subclass distribution and avidity were different between patients with primary AASV and PTU-induced vasculitis. It was suggested that the mechanism of ANCA production in PTU-induced vasculitis was different from that in primary AASV, and the avidity of MPO-ANCA might be associated with disease activity. 相似文献
994.
本文采用MTT微量酶反应比色法,研究了溴氰菊酯对白纹伊蚊C6/36细胞的杀伤作用、形态影响以及受损细胞的恢复。结果发现用溴氰菊酯处理24h后,对C6/36细胞的半数毒性浓度(IC50)为7488μg/ml,且毒性作用强度随着药物浓度增加而增强。溴氰菊酯浓度在20μg/ml以上时可以诱发C6/36细胞形态学改变,表现为细胞呈多形性、细胞间有间隙、胞质内充满颗粒,以后随药物浓度的升高,胞质出现空泡、染色质凝成粗大颗粒或无结构大块、大片细胞脱落、崩解、死亡。高浓度溴氰菊酯(160μg/ml)作用于C6/36细胞,其受损细胞的恢复与作用时间有关,作用24h的细胞,在经历一段生长停滞后,可缓慢恢复,而作用48h的细胞,则不可逆转的死亡 相似文献
995.
目的:观察肉瘤180(S180)移植瘤发展过程中血管生成及血管生成调节因子的变化,并对其调节机制进行探讨。 方法: 利用Km小鼠的S180移植瘤模型,采用FⅧ因子免疫组化染色检测肿瘤血管生成,ELISA和EIA法检测荷瘤鼠肿瘤组织和血浆中血管内皮生长因子(VEGF)和内皮抑制素(endostatin)水平,采用多元回归分析肿瘤组织微血管计数、血管形态与瘤重变化的关系。 结果: 随着荷瘤时间延长,肿瘤组织内微血管计数,瘤内血管相对总量增加,血管的相对面积增大(P<0.05);肿瘤组织匀浆中VEGF水平在荷瘤10 d、15 d均显著高于5 d组(P<0.05);endostatin在肿瘤匀浆和血浆中均在荷瘤15 d达到最高(P<0.05);V/E比值无显著变化;微血管计数、血管相对总面积与瘤重变化有相关性(P<0.01)。 结论: S180移植瘤病期发展中微血管数目增加,血管口径增大,且与瘤重变化呈正相关;肿瘤发展过程中肿瘤局部血管生成正调节因子逐渐增加,促进血管生成;肿瘤局部血管生成调节因子处于相对的平衡。 相似文献
996.
早老素1基因在转染CHO细胞中的表达及其与γ-分泌酶的关系 总被引:4,自引:0,他引:4
目的 研究早老素1(PS1)在淀粉样前体蛋白(APP)加工生成β-淀粉样多肽(Ap)过程中的作用及其与γ-分泌酶的关系。方法构建APP和PSI双基因稳定转染的中国仓鼠卵巢(CHO)细胞株,应用免疫沉淀和印迹、脉冲追踪及ELISA方法,检测PS1的表达和代谢半衰期,分析对Aβ分泌的影响及与γ-分泌酶功能的关系。结果PS1转染的CHO细胞(APP-PSI)表达的主要是相对分子质量为45000的全长PS1蛋白,其半衰期短于1h,而其活性片段的N-末端片段和C-末端片段则相对稳定,半衰期接近16h。突变型PS1(M146L)转染细胞分泌的Ap总量与野生型PS1转染细胞没有明显差别,但分泌的Aβ亚型Ap142是未转染PS1或野生型PS1转染细胞分泌的将近2倍。结论 PS1参与了APP加工生成Aβ的过程,突变型PS1(M16L)导致Aβ142的分泌增加,提示PS1可能就是预期的γ-分泌酶。 相似文献
997.
HLA-DRB1及HLA-DQA1单倍型与乙型肝炎病毒感染结局的关联研究 总被引:5,自引:1,他引:5
目的探讨中国北方汉族人群HLA-DRB1、DQA1单倍型与乙型肝炎病毒(hepatitis B virus,HBV)感染不同结局的关系。方法采用序列特异性引物聚合酶链反应(sequence specific primers polymerase chain reaction,PCR-SSP)技术检测HLA-DRB1、DQA1等位基因,并比较207例慢性乙型肝炎患者,212名无症状HBV慢性携带者(HBV携带者),148例自限性HBV感染者的单倍型频率。结果自限性HBV感染组单倍型DRB1*04-DQA1*0301的频率为10.03%,显著高于慢性乙肝组的3.66%(P=0.0005):DRB1*15/*16-DQA1*0102的频率为6.80%,显著高于慢性乙肝组的1.94%(P=0.0012)和无症状HBV慢性携带者组的1.65%(P=0.004);DRB1*04-DQA1*0302单倍型在慢性乙型肝炎组的频率为3.10%,明显高于自限性HBV感染组的0.39%(P=0.0077)。结论HLA-DRB1、DQA1单倍型与个体感染HBV后的不同结局存在显著关联。 相似文献
998.
舌下神经管及其毗邻结构的显微解剖和临床意义 总被引:2,自引:0,他引:2
目的:研究舌下神经管及其毗邻结构的显微解剖,为舌下神经管疾病的影像学诊断和手术入路的选择提供形态学数据。方法:肉眼和手术显微镜下观测30例(60侧)成人头颅干骨标本的舌下神经管及其毗邻结构。结果:舌下神经管位于枕骨髁的前上方,为一对卵圆形或圆形孔道,内口至外口的长度(8.51±0.91)mm。舌下神经管内口呈双管者5侧(8%);内口后缘与枕骨髁后缘的距离(10.07±0.75)mm,外口后缘至枕骨髁后缘(14.22±1.18)mm。左、右侧枕骨髁的前后径分别为(23.10±1.57)mm、(22.38±2.28)mm。结论:熟悉舌下神经管及其毗邻结构的解剖有利于相关疾病的影像诊断和手术入路的选择。 相似文献
999.
传统的外周神经电缆方程只能描述纵向电场刺激下外周神经兴奋,实验发现在脉冲磁场诱导的横向电场作用下也可使神经兴奋,从而揭示出需要进一步对感应电场兴奋外周神经的机理进行研究。本文研究了横向电场作用下外周神经的兴奋特性,以在体的人体正中神经为例研究了横向电场作用下外周神经兴奋点的位置、刺激阈值、及刺激阈值与纤维半径的关系,以离体的蟾蜍坐骨神经为例研究了刺激阈值与作用时间的关系。实验结果验证了改进的电缆方程的有效性。实验研究成果有助于磁刺激技术的进一步发展与应用。 相似文献
1000.
闭合性颅脑外伤患者事件相关电位的研究 总被引:1,自引:0,他引:1
目的:研究ERP对闭合性颅脑外伤患者脑认知功能变化的评估作用。方法:应用Medicid-03E脑诱发电位仪测定168例闭合性颅脑外伤患者的视觉(图像)、听觉诱发的P3波之潜伏期和波幅,并与正常对照组作比较,54例患者进行复测比较。结果:病人组P3潜伏期较正常对照组明显延长(P<0.001),波幅降低;P3波潜伏期、波幅与患者病情严重程度相关;有原发昏迷者改变尤为突出;随着病情的好转,P3潜伏期逐渐缩短,波幅亦逐渐增高。结论:ERP是测定闭合性颅脑外伤患者脑认知功能变化的一项客观指标。 相似文献