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101.
Helena Malmgren Karl-Henrik Gustavson Jan Wahlstrm Ingrid Arpi-Henriksson Jurgen Bensch Ulf Pettersson Niklas Dahl 《American journal of medical genetics. Part A》1992,44(6):830-833
Twenty-two members of 18 families with autism have been examined for the presence of mutations and abnormal methylation in the FMR-1 region at Xq27.3. All patients fulfilled diagnostic criteria of infantile autism. A characteristic pattern of insertion and methylation were detected after Southern blot analysis in 7 autistic individuals expressing the fragile site at Xq27.3. Normal DNA patterns were observed in 15 autistic boys cytogenetically negative for the fragile site. The results indicate a lack of involvement of the FMR-1 region in infantile autists negative for fragile X expression. © 1992 Wiley-Liss, Inc. 相似文献
102.
The external subdivision of the lateral parabrachial nucleus (LPBE) shows strong Fos-like immunoreactivity (FLI) following anorectic doses of the indirect serotonin agonist dexfenfluramine (DFEN). In an effort to determine the contribution of the LPBE to DFEN-induced anorexia, bilateral ibotenate lesions were made in the LPBE, and the effects of the lesion on DFEN-induced anorexia and FLI as well as c-June-like immunoreactivity (JLI) were examined. It was found that LPBE lesion significantly attenuated DFEN anorexia: in a 1-h food intake test following 24-h food deprivation, DFEN (2 mg/kg) suppressed food intake by 60% in intact rats but only 34% in rats with LPBE lesions. In addition to this behavioral change, LPBE lesion completely abolished DFEN-induced FLI and JLI in the lateral subdivision of the central nucleus of the amygdala (CeL) and laterodorsal subdivision of the bed nucleus of stria terminalis (BSTLD), both of which showed strong FLI and JLI in intact rats. DFEN-induced FLI and JLI in other brain regions were not affected by LPBE lesion, including the ventromedial and lateral hypothalamus, caudate-putamen, and the nucleus of the solitary tract (NST). The parallel loss of DFEN-induced anorexia and FLI/JLI following LPBE lesion raises the novel possibility that LPBE-CeL/BSTLD pathway may be involved in DFEN anorexia. 相似文献
103.
作者曾经体外实验证明,均聚寡脱氧胞嘧啶核苷酸片段(dC14)有抗病毒活性,现继续研究其在体内的作用。不给dC14的对照组小鼠,接种腹水瘤细胞后:100%发病和死亡,潜伏期为6d,存活期11d;给每只小鼠dC14 1.3~3.2 mg,发病率和死亡率降低至20%,疾病潜伏期和存活期推迟。在未经dC14处理的种瘤细胞和淋巴组织与经处理的淋巴组织中,多聚酶链反应(PCR)法都检测到病毒核酸,而正常小鼠中则无此种病毒核酸顺序。研究结果提示,dC14对小鼠SRS腹水瘤的发病和生长有抑制作用。此种抑制作用可能是通过抑制病毒基因的表达来实现的。 相似文献
104.
Intraperitoneal infection with Salmonella abortusovis is partially controlled by a gene closely linked with the Ity gene. 下载免费PDF全文
I P Oswald F Lantier R Moutier M F Bertrand E Skamene 《Clinical and experimental immunology》1992,87(3):373-378
The aim of the present study was to determine whether the Ity gene, which controls the resistance to S. typhimurium infection in mice, also governs the resistance to S. abortusovis, a serotype specific for goat and sheep. During either i.v. or i.p. infection, BALB/c mice (Itys) were not able to control the growth of S. abortusovis and eventually died from infection. In contrast CBA (Ityr) or (C.CB)F1 (Ityr/s) mice were able to control the growth of these bacteria. Using congenic C.D2 Ityr mice, we found that the gene controlling resistance to S. abortusovis was tightly linked to the Ity gene on chromosome 1. Furthermore, in the spleen and the liver of backcross BALB/c x (CBA x BALB/c) mice, the S. abortusovis resistance phenotype cosegregated with the two alleles of the Len-1 gene, a gene tightly linked to the Ity gene. By contrast, in these backcross mice, the level of infection of the peritoneal cavity, the site of inoculation, did not correlated with the Len-1 phenotype of the animal. These results provide evidence that after i.p. inoculation the control of S. abortusovis growth in the spleen and the liver is controlled by the Ity gene, but also suggest that additional gene(s) regulate the number of bacteria at the site of inoculation. 相似文献
105.
106.
力竭运动后大鼠海马脑区谷氨酸受体NR2A蛋白含量和基因表达的变化 总被引:9,自引:0,他引:9
目的:观察力竭运动前后大鼠脑中海马谷氨酸受体NR2A蛋白含量和基因表达的变化,探讨其与运动性疲劳的可能联系。方法:50只SD雄性大鼠,随机分为安静对照组(S,n=10),力竭运动后即刻组(AE1,n=10),力竭运动后恢复0.5小时组(AE2,n=10),力竭运动后恢复3小时组(AE3,n=10)和力竭运动后恢复24小时组(AE4,n=10)。分别采用免疫印迹法和RT-PCR法测定一次性力竭运动后大鼠脑中海马谷氨酸受体NR2A蛋白含量和基因表达。结果:与安静对照组相比,力竭运动后即刻,大鼠NR2A蛋白含量明显升高,而mRNA表达显著减少;恢复0.5小时后,蛋白含量略有下降,mRNA表达显著增加;恢复3小时后蛋白含量显著下降,mRNA表达继续增加;恢复24小时后蛋白含量恢复到安静时水平,mRNA表达则减少至恢复0.5小时后水平。结论:力竭运动后即刻及恢复过程中,大鼠脑中海马谷氨酸受体NR2A蛋白含量及mRNA表达变化趋势不同,提示基因表达对蛋白含量的调控可能具有延迟性。 相似文献
107.
急性等容性血液稀释对血浆ET和CGRP水平的影响 总被引:4,自引:1,他引:3
目的 探讨急性等容性血液稀释 (ANH)对血浆内皮素 (ET)和降钙基因相关肽(CGRP)水平的影响。方法 选择非心脏手术ASAⅠ~Ⅱ级患者 2 0例 ,麻醉前快速输入复方乳酸钠1 0~ 1 5ml/kg。麻醉后从桡动脉放血 1 0ml/kg ,同时经静脉输入等量的 4 %琥珀酰明胶。观察ANH麻醉前 (T0 )、血液稀释完成后 1 0min(T1 )、2 0min(T2 )、30min(T3 )的血液动力学、血浆ET和CGRP浓度的变化。结果 ANH前后MAP、HR、SpO2 和ECG均较稳定。ANH后 1 0min、2 0min血浆ET水平分别为 (1 4 4 4 7± 1 9 1 7) pg/ml和 (1 5 7 1 7± 1 2 4 5 ) pg/ml,但明显高于ANH前的 (1 2 7 6 8±2 0 92 ) pg/ml(P <0 0 5 )。ANH后 1 0min、2 0min血浆CGRP水平分别为 (5 4 72± 2 5 6 5 )pg/ml和(5 5 32± 1 7 94 )pg/ml,也明显高于ANH前的 (4 4 6 2± 1 6 90 ) pg/ml(P <0 0 5 )。而ET/CGRP比值无明显变化。结论 ANH近期血浆ET和CGRP水平均有一定的增加 ,但ET/CGRP比值的变化无统计学意义 ,同时心血管反应不明显 ,表明血浆ET和CGRP的动态平衡对ANH时的循环稳定起着重要的作用 相似文献
108.
用免疫组织化学ABC法,研究了降钙素基因相关肽(CGRP)免疫反应神经纤维在大鼠胆总管末端与十二指肠连接处的分布。大鼠的胆总管末端有较丰富的CGRP免疫反应神经纤维,它们多呈串珠(膨体)状,少数为无膨体的细长纤维。CGRP-IR纤维主要分布肌层及血管周围,在神经纤维的附近可见到含CGRP-IR阳性颗粒的肥大细胞。本实验为神经免疫调节机制的研究提供了形态学依据。 相似文献
109.
K. .SANDVEJ L.K. KRENÁCS S.J. HAMILTON-DUTOIT J.L. RINDUM J.J. PINDBORG G. PALLESEN 《Histopathology》1992,20(5):387-395
Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed. 相似文献
110.
The knee meniscus exhibits extensive spatial variations in native healing capacity, biochemical composition, and cell morphology that suggest the existence of distinct phenotypes for meniscus cells. Constitutive gene expression levels of appropriate extracellular matrix proteins may serve as useful molecular markers of cellular phenotypes; however, relatively little is known of variations in the gene expression for meniscus cells of different regions of the tissue. The objective of the present study was to evaluate constitutive differences between radial inner and outer regions in gene expression for extracellular matrix proteins relevant to the meniscus. A secondary objective was to determine if these region-specific differences in gene expression are maintained after periods of monolayer culture. The innermost regions of the meniscus were found to constitutively express higher mRNA levels for proteins highly expressed in articular cartilage, including aggrecan, type II collagen, and NOS2. In contrast, the outer meniscus was found to contain higher gene expression for proteins associated with fibrous tissues including type I collagen, and the proteases MMP2 and MMP3. Isolated inner and outer meniscus cells maintained these region-specific gene expression patterns for collagens and proteoglycans during short-term monolayer culture. The results provide new information that suggests the utility of constitutive gene expression levels as molecular markers to distinguish tissue and cells of the inner and outer meniscus. 相似文献