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61.
Using «consensus» primers derived from the LTR region of 15 HIV-1 isolates, a fragment of 583 bp was amplified from human DNA. Even though specificity was confirmed by Southern blot analysis with a conserved LTR oligonucleotide probe, no significant homologies were detected to either retroviral regions or human or non-human published sequences. Nevertheless, when used as a probe, the 583-bp fragment identified a unique DNA sequence in the human genome on chromosome 1, and cross-reactive sequences in monkey, but not mouse, DNA. This novel, unique and conserved sequence of 583 bp was used to isolate a human HS-1 clone in which the structural property of a viral LTR could be identified.  相似文献   
62.
BACKGROUND: The Sl(a) (Knops system) located on complement receptor 1 (CR1) has been associated with malarial rosetting, a process associated with severe malarial infections. Moreover, the long homologous repeats (LHRs) B and C of CR1 were implicated in rosette formation. As a step toward mapping the location of Knops system antigens, truncated CR1 proteins have been expressed and their ability to inhibit antibodies to the high-incidence Knops system antigens was assessed. STUDY DESIGN AND METHODS: Individual LHRs (A, B, C, and D) of CR1 of the common CR1*1 (F) allotype were expressed as secreted forms in 293T cells. Their abilities to specifically neutralize Knops system antibodies were tested by both hemagglutination and flow cytometry. RESULTS: Three examples of anti-Kn(a) (n = 6) were almost completely inhibited by LHR-C and three by LHR-D. Two examples of anti-McC(a) (n = 2) and seven examples of anti-Sl(a) (n = 8) were inhibited by LHR-D. Both examples of anti-Yk(a) (n = 2) were partially inhibited by LHR-D. CONCLUSION: The high-incidence Knops system antigens reside within LHR-D and to a lesser extent within LHR-C. Because of the role of Sl(a) antigen in malaria rosetting, these results indicate that LHR-D may represent an additional malaria interaction region in CR1.  相似文献   
63.
64.
        剖宫产粘连是指剖宫产手术后盆腹腔组织和器官之间的异常纤维连接,根据部位和涉及组织和器官不同,粘连可能会导致各种并发症如疼痛、不孕、肠梗阻等。为了预防和减少剖宫产粘连的发生,结合国内剖宫产现状制定本共识。  相似文献   
65.
目的 采用肠道细菌基因间重复序列(enterobacterial repetitive intergenic consensus,ERIC)基因分型技术对副溶血性弧菌进行分型,评估其基因多态性,探讨其在鉴别该菌散发和暴发中的应用.方法 采用ERIC-PCR分型方法对187例分离自患者、海产品和环境中的副溶血性弧菌基因组模板进行扩增,根据PCR产物中不同产物片段组合模式获得基因型,采用进化树分析软件直观评价不同基因型的相似性,并根据离散程度分为不同的族,同时进行血清分型.结果 187例菌株可获得产物长度160~2780 bp共16种大小不同的PCR产物片段,所有菌株根据扩增片段分布可分为59种基因指纹模式,通过进化树软件可分为12族,血清分型结果表明O3∶K6为86% (161/187),O2、O4和O12占4% (8/187),10% (18/187)无法分型.结论 ERIC-PCR分型结果表明,我国分离的副溶血性弧菌具有较高基因多态性,ERIC-PCR具有高分辨力,可用于快速基因分型.  相似文献   
66.
Invertebrate immune diversity   总被引:1,自引:0,他引:1  
The arms race between hosts and pathogens (and other non-self) drives the molecular diversification of immune response genes in the host. Over long periods of evolutionary time, many different defense strategies have been employed by a wide variety of invertebrates. We review here penaeidins and crustins in crustaceans, the allorecognition system encoded by fuhc, fester and Uncle fester in a colonial tunicate, Dscam and PGRPs in arthropods, FREPs in snails, VCBPs in protochordates, and the Sp185/333 system in the purple sea urchin. Comparisons among immune systems, including those reviewed here have not identified an immune specific regulatory “genetic toolkit”, however, repeatedly identified sequences (or “building materials” on which the tools act) are present in a broad range of immune systems. These include a Toll/TLR system, a primitive complement system, an LPS binding protein, and a RAG core/Transib element. Repeatedly identified domains and motifs that function in immune proteins include NACHT, LRR, Ig, death, TIR, lectin domains, and a thioester motif. In addition, there are repeatedly identified mechanisms (or “construction methods”) that generate sequence diversity in genes with immune function. These include genomic instability, duplications and/or deletions of sequences and the generation of clusters of similar genes or exons that appear as families, gene recombination, gene conversion, retrotransposition, alternative splicing, multiple alleles for single copy genes, and RNA editing. These commonly employed “materials and methods” for building and maintaining an effective immune system that might have been part of that ancestral system appear now as a fragmented and likely incomplete set, likely due to the rapid evolutionary change (or loss) of host genes that are under pressure to keep pace with pathogen diversity.  相似文献   
67.
        随着社会的发展,人们对美的追求越来越高,小阴唇整形也逐渐受到人们的关注。尽管小阴唇整形术方法有很多,但手术指征、手术方式选择、围术期管理及术后并发症防治等缺乏统一的标准[1-2]。中国整形美容协会女性生殖整复分会组织专家,根据文献报道[3]和专家经验,经过反复的讨论和修改,对小阴唇整形术提出如下共识,以期为临床医生对小阴唇肥大的诊治及整形决策提供参考及借鉴。 浏览更多请关注本刊微信公众号及当期杂志。  相似文献   
68.
自然流产(spontaneous abortion,SA)是妇产科最常见的妊娠并发症之一。育龄期女性发生1次SA的风险为10%左右[1]。复发性流产(recurrent spontaneous abortion,RSA)的发生率为1%~5%[2],RSA的复发风险随着流产次数的增加而上升。曾有3次以上连续自然流产史的患者再次妊娠后胚胎丢失率为40%~80%[3]。如果不及时干预,不仅会给患者及其家庭带来严重的经济负担,而且还将对患者的身心健康造成极大的影响。 浏览更多请关注本刊微信公众号及当期杂志。  相似文献   
69.
        晚期产后出血(late postpartum hemorrhage)是产褥期常见并发症,发生率为0.5%~2%,临床医生对其重视程度和处理方案与普通产后出血相比相差甚远[1-2]。如未及时识别和正确处理,同样可能发生大出血、休克等严重并发症,甚至危及生命。目前国际上缺乏共识或指南,鉴于此,中华医学会围产医学分会在参考国外晚期产后出血诊治文献的基础上[2-3],结合我国现状特制定本专家共识,由于缺乏高质量的证据,本文未对推荐意见进行分级,希望在尽快规范晚期产后出血临床处理的同时,推动良好设计的临床研究的开展。  相似文献   
70.
A rare collection of serum samples from patients with hepatitis C virus (HCV) infection followed up from the onset of clinical symptoms was acquired. RNA corresponding to the hypervariable region 1 (HVR1) of E2 protein of HCV isolated from nine patients was reverse-transcribed, amplified, sequenced, and HVR1 amino acid sequences were deduced. These sequences and a selection of HVR1 amino acid sequences of matching HCV genotypes from protein and translated DNA sequence databanks were used to create the HVR1 amino acid consensus. The degenerated peptides mimicking N- and C-termini of the consensus were synthesized. Most (76%) of 17 patients followed up for the period from 1 week to a minimum of 7 months from the onset of acute symptoms developed antibodies reacting with peptides representing N- and/or C- termini of HVR1. Antibody recognition of the consensus HVR1 peptides indicates that the variability of HVR1 sequence on the protein level is limited with certain conserved structure(s) being untouched. A tendency was observed for a slower development of anti-HVR1 antibody response in patients developing chronic HCV, as compared to those with self-limiting HCV infection.  相似文献   
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