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51.
Udaya DeSilva Laura Elnitski Jacquelyn R Idol Johannah L Doyle Weiniu Gan James W Thomas Scott Schwartz Nicole L Dietrich Stephen M Beckstrom-Sternberg Jennifer C McDowell Robert W Blakesley Gerard G Bouffard Pamela J Thomas Jeffrey W Touchman Webb Miller Eric D Green 《Genome research》2002,12(1):3-15
Williams syndrome is a complex developmental disorder that results from the heterozygous deletion of a approximately 1.6-Mb segment of human chromosome 7q11.23. These deletions are mediated by large (approximately 300 kb) duplicated blocks of DNA of near-identical sequence. Previously, we showed that the orthologous region of the mouse genome is devoid of such duplicated segments. Here, we extend our studies to include the generation of approximately 3.3 Mb of genomic sequence from the mouse Williams syndrome region, of which just over 1.4 Mb is finished to high accuracy. Comparative analyses of the mouse and human sequences within and immediately flanking the interval commonly deleted in Williams syndrome have facilitated the identification of nine previously unreported genes, provided detailed sequence-based information regarding 30 genes residing in the region, and revealed a number of potentially interesting conserved noncoding sequences. Finally, to facilitate comparative sequence analysis, we implemented several enhancements to the program, including the addition of links from annotated features within a generated percent-identity plot to specific records in public databases. Taken together, the results reported here provide an important comparative sequence resource that should catalyze additional studies of Williams syndrome, including those that aim to characterize genes within the commonly deleted interval and to develop mouse models of the disorder. 相似文献
52.
Gamma delta T cells in rhesus monkeys and their response to simian immunodeficiency virus (SIV) infection. 总被引:1,自引:0,他引:1 下载免费PDF全文
The principal cause of IL-2 deficiency, a common feature of both murine lupus and human SLE, remains obscure. Recent studies of our own as well as others have shown that dehydroepiandrosterone (DHEA), an intermediate compound in testosterone synthesis, significantly up-regulates IL-2 production of T cells, and that administration of exogenous DHEA or IL-2 via a vaccinia construct to murine lupus dramatically reverses their clinical autoimmune diseases. Thus, we have examined serum levels of DHEA in patients with SLE to test whether abnormal DHEA activity is associated with IL-2 deficiency of the patients. We found that nearly all of the patients examined have very low levels of serum DHEA. The decreased DHEA levels were not simply a reflection of a long term corticosteroid treatment which may cause adrenal atrophy, since serum samples drawn at the onset of disease, which are devoid of corticosteroid treatment, also contained low levels of DHEA. In addition, exogenous DHEA restored impaired IL-2 production of T cells from patients with SLE in vitro. These results indicate that defects of IL-2 synthesis of patients with SLE are at least in part due to the low DHEA activity in the serum. 相似文献
53.
为解决细胞内抗原应用免疫金银法染色时背景过重的问题,建立了甘氨酸二次阻断的处理方法,效果较好。 相似文献
54.
An affinity chromatography technique was utilized to isolate and purify the receptors of Escherichia coli K88ac(+) fimbriae from the mucus of the small intestines of newborn piglets. Purified K88ac+ fimbriae were covalently immobilized onto a beaded agarose matrix (Sepharose 4B). The immobilized fimbriae were used for the affinity purification of the K88ac+ receptors. Only two major proteins were tightly and specifically bound to the immobilized fimbriae after the column containing bound receptor was washed exhaustively with a buffer containing a high concentration of salt and a detergent. The receptors were eluted as a single component at a low pH. The isolated proteins were then subjected to enzyme-linked immunosorbent assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot (immunoblot) analyses. The two proteins were of high purity, were responsible for nearly all of the fimbrial binding capacity of the crude mucus, and had molecular masses of 26 and 41 kDa. The method for isolation of E. coli binding proteins is simple and yields purified intestinal receptors in a single chromatographic run. The intestinal mucus of different piglets has different proportions of the two receptor proteins. 相似文献
55.
川芎嗪对内毒素脂多糖诱导的体外血脑屏障模型通透性增高的保护作用及其机制 总被引:1,自引:0,他引:1
目的:探讨川芎嗪对内毒素脂多糖(LPS)诱导的体外血脑屏障模型通透性增高的保护作用及其调控机制。方法:利用脑微血管内皮细胞与星型胶质细胞共培养建立体外大鼠血脑屏障模型,随机分为正常对照组、川芎嗪对照组、LPS干预组和川芎嗪治疗组。采用γ计数仪检测~(125)I-BSA通透量观察体外血脑屏障模型通透性的改变,Western印迹法检测紧密连接蛋白(zonula occludens-1,ZO-1)表达量的变化。结果:LPS使体外血脑屏障模型对~(125)I-BSA的通透量明显增加,脑微血管内皮细胞ZO-1蛋白表达下降,川芎嗪治疗组能明显拮抗LPS的上述作用。结论:川芎嗪对LPS诱导的体外血脑屏障通透性增高具有保护作用,其机制与它能影响血脑屏障紧密连接蛋白ZO-1表达有关。 相似文献
56.
Springer Link及其收录的医学期刊分析 总被引:4,自引:0,他引:4
目的:向图书馆员和用户介绍Springer Link,对其收录的医学期刊进行深入分析,使该数据库得到更好的利用。方法利用《外国报刊目录》和美国《医学索引》(IM)的《引用期刊一览表》等对Springer Link收录的英文医学期刊从权威性、出版地分布、学科分布和收藏年限等方面进行考查。结果86%的期刊被IM引用,欧洲——尤其是德国的期刊较多,医学各学科都有相应的期刊被收录,但数量分布不均,有所偏重,72.7%的期刊可以保证至少近5年或自创刊以来的文献。结论Springer Link所提供的全文医学期刊服务质量较上乘,并有自己的特色。 相似文献
57.
Boping Liu Ghee Chong Koo Eu Hian Yap Kim Lee Chua Yunn-Hwen Gan 《Infection and immunity》2002,70(2):504-511
Burkholderia pseudomallei is the causative agent of melioidosis, an infectious disease with protean clinical manifestations. The major route of infection is thought to be through subcutaneous inoculation of contaminated soil and water, although ingestion and inhalation of contaminated aerosols are also possible. This study examines infection through the intranasal route in a murine model to mimic infection through inhalation. Two strains of mice, C57BL/6 and BALB/c, exhibit differential susceptibilities to the infection, with the C57BL/6 mice being considerably more resistant. To examine host factors that could contribute to this difference, bacterial loads and cytokine profiles in the two strains of mice were compared. We found that infected BALB/c mice exhibited higher bacterial loads in the lung and spleen and that they produced significantly higher levels of gamma interferon (IFN-gamma) in the serum than C57BL/6 mice. Although tumor necrosis factor alpha and interleukin-1 could be detected in the nasal washes and sera of both strains of mice, the production in serum was transient and much lower than that of IFN-gamma. C57BL/6 mice also exhibited memory responses to bacteria upon reinfection, with the production of serum immunoglobulin G (IgG) and mucosal IgA antibodies. Thus, it is possible that the production of systemic and mucosal antibodies is important for protection against disease in C57BL/6 mice. 相似文献
58.
Human macrophages acquire a hyporesponsive state of tumor necrosis factor alpha production in response to successive Mycobacterium avium serovar 4 stimulation. 下载免费PDF全文
Human macrophages (M phi) from most donors respond to inoculation with Mycobacterium avium serovar 4 (M. avium) by tumor necrosis factor alpha (TNF-alpha) production, which is of critical importance for proper defense against microorganisms. An initial infection of M phi with M. avium results in an incapacity to accumulate TNF-alpha mRNA after reinfection with M. avium, indicating adaptation to a hyporesponsive state by preexposure of the cells to M. avium. Adaptation to stimulation with M. avium is abrogated by the cyclooxygenase inhibitor indomethacin. In the presence of prostaglandin E2, indomethacin-exposed, M. avium-treated M phi remain unresponsive to a subsequent M. avium stimulus to increase steady-state TNF-alpha mRNA, suggesting that prostaglandin E2 is instrumental for the adaptation to an M. avium challenge. TNF-alpha mRNA accumulation induced by a second M. avium stimulus in the presence of indomethacin is blocked by the protein tyrosine kinase inhibitor herbimycin. In contrast, the initial M phi response to M. avium is inhibited by staurosporin, an inhibitor of phospholipid Ca(2+)-dependent protein kinases, indicating that the initial and the successive TNF-alpha responses to M. avium are dependent on different mechanisms. 相似文献
59.
目的评价骨水泥强化椎弓根螺钉固定治疗老年退行性腰椎疾病的近期临床疗效。方法回顾性分析2011年6月~2013年5月采用聚甲基丙烯酸甲酯(PMMA)骨水泥强化椎弓根螺钉固定结合后路椎体间植入聚醚醚酮(PEEK)材质椎间融合器治疗老年退行性腰椎疾病30例。所有患者术前骨密度检测均符合骨质疏松诊断(超声骨密度值测定-2.5)。结果 30例患者均顺利完成手术,术中无神经及硬膜损伤,骨水泥无严重渗漏,术后复查X线、CT显示骨水泥分布均匀。随访10~21个月,平均(16±2.11)个月,神经受压症状均得到改善。VAS评分术前(7.01±1.44)、术后6个月随访为(3.00±0.57)、末次随访为(2.23±1.19);JOA评分术前为(9.98±5.64)、术后6个月随访为(17.99±1.41)、末次随访为(18.42±1.47);ODI评分术前为(0.64±0.24)、术后6个月为(0.27±0.07)、末次随访为(0.22±0.09)。三项评分术后6个月、末次随访分别与术前对比差异有统计学意义;术后6个月和末次随访对比差异无统计学意义。末次随访时复查X线或CT显示椎弓根螺钉无松动,椎间融合器无下沉,椎间融合满意,融合率为86.7%。结论使用骨水泥强化椎弓根螺钉能够提高螺钉对伴有骨质疏松的椎体的握持力,防止椎弓根螺钉松动,保证较高的椎间融合率,是治疗老年退行性腰椎疾病一种安全而有效的手术方式。 相似文献
60.
小学生中抑郁症状现况调查 总被引:6,自引:0,他引:6
目的:初步了解儿童中抑郁障碍的患病现况,探讨儿童抑郁的常见表现。方法:使用儿童抑郁自评量表(DSRSC)调查长沙市某小学二年级到六年级的565名小学生,并对量表总分≥划界分的学生进行面谈。结果:在565名小学生(男生290名,女生275名)中,量表总分≥划界分的有97名,占总人数的17.17%。使用CCMD-3成人抑郁发作的诊断标准对量表总分≥划界分的93名进行了面谈(面谈率为95.90h,),发现符合抑郁发作的症状学标准的有38名(其中男生28名,女生10名),占面谈者的40.9%,无一名达到病程标准和严重程度标准。结论:在儿童中抑郁症状存在较普遍,但真正构成抑郁症临床诊断的极少。 相似文献