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1.
人-人杂交瘤     
一种生产人一人杂交瘤方法的专利授予陆军附属的Mayo医院的R.E.Ritts。大多数杂交瘤都是由人和鼠的细胞融合而成的,但人一人杂交瘤却有其独到之处。  相似文献   

2.
一个科学家小组上周请求美国主管遗传工程安全事务的监护人允许将一个合成基因导入人体。它的发起人说:给政府检查人员介绍的第一次人体试验是一次“演习”。这程序将不治疗疾病,但是,它将试验把外源基因插入人体的方法。它也将有助于逐渐地缓和将有争论的技术应用到实际的争议。主要的实验发起人——W·French Anderson 和必须审查该提案的国家卫生研究院正尝试期待非议。上周,Anderson 将十公斤左右的文件呈递给 NIH 的重组 DNA 咨询委员会时  相似文献   

3.
生态人     
  相似文献   

4.
疍家人     
<正>雷州半岛地处粤西,特殊的地理环境和资源养育了一个特殊的群体——蛋家人。蛋家人,蛋民,又称水上居民,他们浮海泛舟、以水为伴、以舟为家、以渔为业。压迫歧视历史上的蛋民社会地位极低,不许登岸,不得陆居,死后不得葬陆,不准穿新衣、鞋袜上街;不准与陆上人通婚,不准将棺材抬过陆上人村前,不准到陆上人的寺庙参神拜佛,婚嫁等宴席不准设在陆上人的祠堂、庙宇,不收水上子弟入学读书等。  相似文献   

5.
看山人     
天目山是50年前新中国第一批保护区之一。与那些远离城市连绵上万平方公里的保护区相比,这个靠近都市仅区区40多平方公里的袖珍型保护区,自建立之后它的历代看山人遇到了一系列相同寻常的挑战。[编者按]  相似文献   

6.
熊猫和人     
疾飞的箭雨中迈着跟跄的脚步,刀斧的旋风中退出蛰居的幽谷,活化石,从第四纪冰川遗存的熊猫却没有逃脱人类的追捕4|退出长江,退出黄河,退出缅甸l印支北部,一直龟缩到川西北峥嵘的大山中,与世无争,成为隐士,竹海落户,.生物史,该用多少惊双号,写下这令人揪心的一幕:…接看,该用一连串问号,问胜利对于人类为什么这样严酷:问银盘似的月亮为何被烟尘染黑?问迷人钓管弦为何在噪音中沉没?间风砂为什么成为春天的使臣?问江河为什么成大鱼虾的坟墓?中国,毅然划出一片片自然保护区,厚文明史之中的悲剧在地图上一个个何夸今结束,…受探护的权仅是熊猫吗,…  相似文献   

7.
柳江人     
柳江人是四、五万年前的人类祖先,属旧石器时代晚期的人类。他们很早就在柳江流域劳动、生活着。说起柳江人的发现史,话就长了。那是在1958年9月中旬,工人们在距柳州市东南十六公里的新兴农场的通天岩洞中挖掘岩泥时,在离洞口18米处偶然发现一个完整的人的头骨化石(缺下颌骨),接着再进十米又发现了人的四个胸椎、五个腰椎、骶骨、右髋骨和左右股骨各一段。大量的哺乳动物化石也在这里出土。消息传开后,中国科学院的研究人员赶到现场,在农场场长李殿同志引导下,对通天洞作了考察。人化石送到北京后,经著名的人类学家吴汝康的研究,发表了题为《广西柳江发现的人类化石》的重要论文,从此柳江人的声誉传四海。柳江人头骨有许多特点证明他属于黄种人,如他的脸面部、鼻梁和嘴部的突出程度与现代黄种人一致,硬腭大小中等,上门齿舌面呈铲形,他的年龄虽已超过四十岁,但是第三臼齿仍未长出来,这些在现代黄种人  相似文献   

8.
宝天曼人     
中原大地,藏龙卧虎,南阳古城,英才辈出。从博学的张衡,到睿智的诸葛先生,从妙手回春的张仲景,到豪迈大气的岑参,无数英雄才俊,代代墨客骚人,指点历史苍穹,吟罢江山如画,在南阳这片热土上,尽放炫目光彩,“江山代有才人出,各领风骚数百年”。而今,不再是英雄,不再是豪杰,有的只是普通的劳动者,洒着艰辛的汗水,怀着对未来的希望,在平凡中耕耘,秀美青山,快乐人生正是从这汗水和辛劳中孕育出来的。真可谓“水钟灵秀,山毓雄浑,南阳具荆秦特色;民尚忠诚,士崇道义,北楚存汉魏遗风”。  相似文献   

9.
资阳人     
娄玉山  马宁 《化石》2014,(3):66-67
正1949年新中国成立,国家建设百废俱兴,政务院(现国务院)决定修建成渝铁路。1950年6月15日,修建成渝铁路工程正式开工。9月初,资阳铁路段开始破土动工。到11月下旬,负责该路段工程的解放军第四总队的官兵们先后在资阳莲花山处发掘出脊椎动物化石等标本60余件。消息很快传到西南军政委员会文教部,文教部向西南军政委员会作了及时汇报。时任中共中央西南局第一书记、西南军政委员会副主席、西南军区政委的邓小平同志组织召开了相关人员的全体大会,在会议后作出了两项决议:  相似文献   

10.
中国有句古语:人必先自侮,而后人侮之。其实反过来可能也是一样的。要把一件事情做好,自己必须首先相信这件事情通过努力是一定能够做好的,然后是作出必要的努力。  相似文献   

11.
Prevalence of antibody to human herpesvirus 6 in women and children   总被引:5,自引:0,他引:5  
The antibody prevalence to human herpesvirus 6 (HHV-6) was compared between pregnant women and control women of similar ages in Thailand. No significant difference was detected in the antibody positive rate and antibody titers between both groups. The antibody titers in sera collected from pregnant women at 1st and 3rd trimester remained unchanged. Next, the antibody prevalence in infants were examined and the positive rate decreased until 3 months and started to increase from 6 months after birth. The present results suggest that the reactivation of HHV-6 might not occur during pregnancy and this virus infects infants postnatally.  相似文献   

12.
A biologic, immunologic and molecular characterization of an HHV-6 isolate (BA92) rescued by the peripheral blood mononuclear cells of a child affected by Exanthem subitum is reported. The comparison with the known HHV-6 prototype strains showed that BA92 is indistinguishable from the Z29 isolate, and can be included in the variant B group of HHV-6. A seroepidemiologic analysis of the antibody response to BA92 of normal individuals as well as patients affected by diseases potentially associated to HHV-6 infection has shown an overall seroprevalence of 81%, and that no variations in seroprevalence or in antibody geometric mean titer are observed assaying the sera also against G.S., U1102, or Z29 infected cells, respectively. These findings indicate: (1) HHV-6 infection is widely diffuse in Italy; (2) it is not possible to discriminate between the viral variants by the currently available IF assays, and (3) no conclusions can be drawn on the potential association of HHV-6 with any of the diseases examined.  相似文献   

13.
用汉坦病毒汉滩株(76-118)重组核蛋白作为免疫印迹法(WesternBlot以下简称WB)的诊断抗原,用于实验感染大鼠血清抗体效价测定。同时与用汉城株(SR-11)感染的Vero-E6细胞作抗原的间接免疫荧光法(以下简称IFA)进行比较。WB法对3/4标本在大鼠接种病毒后第3天测得血清IgM阳性,而IFA法仅1/4标本出现阳性,IFA效价为1:5120的血清,WB效价为1’:40960,且在血清1:10稀释时反应带亦清晰。两种方法分别测定64份大鼠血清。甩IFA法,44份(68.8%)出现类似阳性的荧光颗粒,而用WB法测定,无特异的反应带出现。非感染Vero-E6细胞作IFA抗原,30份(46.9%)与正常细胞抗原有反应,此结果表明WB法在特异性和敏感性方面均高于IFA法。IFA法中的非特异性反应系血清与细胞成份之反应。  相似文献   

14.
Proteins specific for human herpesvirus 6 (HHV-6)-infected human T cells (HSB-2) were examined by using polyclonal rabbit antibodies and monoclonal antibodies against HHV-6-infected cells and human sera. More than 20 proteins and six glycoproteins specific for HHV-6-infected cells were identified from [35S]methionine- and [3H]glucosamine-labeled total-cell extracts. Polyclonal rabbit antibodies immunoprecipitated 33 [35S]methionine-labeled HHV-6-specific polypeptides with approximate molecular weights ranging from 180,000 to 31,000. In immunoprecipitation and Western immunoblot reactions, a patient's serum also recognized more than 30 HHV-6-specific proteins and seven glycoproteins. In contrast, sera from individuals with high-titered antibodies against other human herpesviruses reacted with fewer HHV-6-infected cell proteins, and only a 135,000-Mr polypeptide was prominent. Monoclonal antibodies to HHV-6-infected cells reacted with single and multiple polypeptides specific for virus-infected cells and immunoprecipitated three distinct sets of glycoproteins, which were designated gp105k and gp82k, gp116k, gp64k, and gp54k, and gp102k.  相似文献   

15.
Human herpesvirus 6 (HHV-6) and human herpesvirus 7 (HHV-7) are closely related to each other. Interaction between the two viruses at the time of primary HHV-7 infection is suggested by in vivo and in vitro studies. However, interaction between the two viruses in organ transplant recipients has not been analyzed. We analyzed serially collected plasma samples obtained from 40 living related liver transplant recipients by serological assay (indirect immunofluorescence assay, IFA) and polymerase chain reaction (PCR). Significant increase or seroconversion of HHV-6 IgG and HHV-7 IgG antibody titers were observed in 45% and 58% of recipients respectively. Positive rate of IgM HHV-6 antibody increased up to 35% at 4 weeks after transplantation. However, no remarkable peak in the positive rate of HHV-7 IgM antibody was demonstrated. HHV-6 and HHV-7 DNA were detected in plasma in 15 (38%) and 16 (40%) of the 40 recipients respectively. HHV-6 DNA was detected in 10 (26%) of the 38 recipients at 2 weeks after transplantation. The positive rate of the virus genome in plasma gradually decreased after that time. HHV-7 DNA was detected in 5 (14%) of the 37 recipients at 2 weeks after transplantation; no obvious peak in the positive rate of HHV-7 DNA was demonstrated. Antibody responses involving both HHV-6 and HHV-7, including either a significant increase in IgG antibody titers or positive identification of IgM antibody were observed in 17 (43%) of the 40 recipients. Thirteen out of the 17 recipients demonstrated concurrent antibody response against both viruses. HHV-7 antibody response preceded the HHV-6 antibody response in 2 of the remaining 4 recipients, whereas the opposite was true in the other 2 recipients. Both HHV-6 and HHV-7 DNA were detected in 7 (18%) of the 40 recipients. In 4 of those 7 recipients, DNA from both viruses was concurrently detected, 3 of whom had HHV-7 DNA repeatedly detected after first detection of the virus DNA. The detection of HHV-7 DNA preceded the detection of HHV-6 DNA in 2 recipients, whereas HHV-6 DNA appeared first in 1 recipient.  相似文献   

16.
The recent isolation of human herpesvirus 7 (HHV-7) from activated CD4+ T lymphocytes of a healthy individual raises questions regarding the prevalence of this virus in humans and its immunological relationship to previously characterized human herpesviruses. We report that HHV-7 is a ubiquitous virus which is immunologically distinct from the highly prevalent T-lymphotropic HHV-6. Thus, (i) only two of six monoclonal antibodies to HHV-6 cross-reacted with HHV-7-infected cells, (ii) Western immunoblot analyses of viral proteins revealed different patterns for HHV-6- and HHV-7-infected cells, (iii) tests of sequential serum samples from children revealed seroconversion to HHV-6 without concomitant seroconversion to HHV-7, and (iv) in some instances HHV-7 infection occurred in the presence of high titers of HHV-6 antibodies, suggesting the lack of apparent protection of children seropositive for HHV-6 against subsequent infection with HHV-7. On the basis of the analyses of sera from children and adults it can be concluded that HHV-7 is a prevalent human herpesvirus which, like other human herpesviruses, infects during childhood. The age of infection appears to be somewhat later than the very early age documented for HHV-6.  相似文献   

17.
In order to clarify the protective immune responses against a newly identified herpesvirus, human herpesvirus 6 (HHV-6), we established HHV-6-specific human T-cell clones and examined their functional properties. Five CD3+CD4+CD8- T-cell clones, which proliferated in response to stimulation with two different strains of HHV-6 in the presence of autologous antigen-presenting cells but not with herpes simplex virus type 1 or human cytomegalovirus, were established from peripheral blood lymphocytes of a healthy individual. The proliferative response of all T-cell clones to HHV-6 antigen was inhibited by addition of anti-HLA-DR monoclonal antibody, indicating that these clones were human leukocyte antigen (HLA) class II DR restricted. Of the five clones, two lysed HHV-6-infected autologous lymphoblasts, but not HHV-6-infected allogeneic cells or natural killer-sensitive K562 cells (group 1); one showed cytotoxicity against HHV-6-infected autologous lymphoblasts as well as HHV-6-infected allogeneic cells and K562 cells (group 2); and the remaining two showed no cytotoxic activity (group 3). The cytotoxic activity of group 1 was inhibited by addition of anti-HLA-DR monoclonal antibody to the culture, whereas this monoclonal antibody had no effect on the cytotoxicity of group 2 and did not induce the cytotoxicity of group 3. Perforin, which is one of the mediators of cytotoxicity, was abundantly expressed in group 1 and 2 clones. Moreover, all groups of clones produced gamma interferon after culture with antigen-presenting cells followed by HHV-6 antigen stimulation. These results suggest that HHV-6-specific CD4+ T cells have heterogeneous functions.  相似文献   

18.
Human herpesvirus-6 (HHV-6) is a major pathogen associated with diseases of recipients of hematopoietic stem cell transplants (HSCT). We have isolated HHV-6 in Korean HSCT recipients and carried out a prospective investigation of its prevalence. We obtained peripheral blood from HSCT recipients who had signs of HHV-6 infection. Cord blood mononuclear cells (CBMC) and Sup-T1 cells were used to culture the HHV-6. Indirect immunofluorescence assays (IFA), and the polymerase chain reaction (PCR) were employed to detect HHV-6. The prevalence of HHV-6 infection in HSCT recipients was calculated on the basis of the PCR results. HHV-6 was isolated from four clinical samples. After culturing the HHV-6 in CBMC, the standard strain and the four clinical isolates were propagated in Sup-T1 cells. The infected cells became grossly enlarged and multinucleate after 7-21 days. The virus was identified primarily on the basis of the morphological changes of the cultured cells, and confirmed by specific IFA with monoclonal antibody to HHV-6. HHV-6 was detected in each sample by PCR with primers specific for the major immediate early gene. Sequencing of the standard strain and PCR products confirmed identification of the HHV-6B variant. By PCR we detected 415 instances of HHV-6 in 3966 samples (14.6% of peripheral blood mononuclear cells and 6.3% of sera), and HHV-6 DNAemia was most frequent from the second to the fourth week after HSCT.  相似文献   

19.
The alpha(4) integrin antagonist natalizumab was shown to be effective in patients with immune-mediated disorders but was unexpectedly associated with JC polyomavirus associated progressive multifocal leukoencephalopathy (PML) in two multiple sclerosis (MS) and one Crohn's disease patients. Impaired immune surveillance due to natalizumab treatment may have contributed to the JCV reactivation. As HHV-6 has been suggested to play a role in MS, we asked whether this virus could also have been reactivated during natalizumab therapy. Matched sera and CSF from a limited set of MS patients treated with and without natalizumab were examined for evidence of HHV-6. In addition, we also superinfected a persistent JC virus infected glial cell with HHV-6A to determine if JC virus can be increased. Elevated serum HHV6 IgG and HHV-6A DNA was detected in the CSF of a subset of patients but not controls. We confirmed that superinfection with HHV-6 of a JC virus infected glial cells increased expression of JCV. These results support the hypothesis that treatment with natalizumab may be associated with reduced immune surveillance resulting in reactivation of viruses associated with MS pathogenesis.  相似文献   

20.
Four tests for antibody to varicella-zoster (V-Z) virus were compared; these were tests of complement fixation (CF), neutralization (NT), fluorescent antibody to membrane antigen (FAMA) and immune adherence hemagglutination (IAHA). Fifty-two sera from patients with varicella and zoster and from recipients of live varicella vaccine were examined by the 4 tests. The CF test was least sensitive, but the antibody titers by the NT, FAMA and IAHA tests were roughly comparable. The IAHA test was the simplest and fastest to perform, and appeared suitable for routine serological assay to V-Z virus. The correlation between the IAHA antibody titer and susceptibility of individuals to clinical varicella was investigated retrospectively using sera obtained during 2 outbreaks of varicella in an institution for children, where all the unvaccinated children had developed varicella symptoms. Most of the 25 pre-exposure sera from unvaccinated children examined by the IAHA test had tiers of less than 1:2. In contrast, all the 23 sera from vaccinated children who did not develop varicella had detectable antibody titers of 1:2 to 1:64. These results indicate that the IAHA titer reflects the susceptibility or resistance of individuals to clinical varicella.  相似文献   

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