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961.
目的 探讨PARKIN基因与中国人常染色体隐性遗传早发型帕金森病(autosomal recessive early-onset Parkinson’s disease,AREP)家系的关系。方法 对3个AREP家系的6例患者和23位成员进行系统的临床检查并进行PARKIN基因PCR扩增,产物通过变性高压液相色谱(denaturing high—performance liquid chmnatogmphy,DHPLC)进行突变检测,阳性结果标本进行基因测序。结果 所有研究对象的PARKIN基因外显子均扩增成功。DHPLC检测和基因测序发现一个家系中存在PARKIN基因杂合Gly284Arg突变,另一个家系中存在PARKIN基因Ser167Asn多态性,且患者均有环境毒物接触史。结论 PARKIN基因杂合Gly284Arg突变在环境因素的协同作用下可能导致发病。PARKIN基因Ser167Asn多态性是帕金森病的易感因素,汞中毒与其共同作用可能导致发病。  相似文献   
962.
The aim of this study was to test the safety and efficacy of fragmented autologous adipose tissue (FAT) grafts for revascularization in aortoiliac occlusive disease. Twenty-seven patients with atherosclerotic aortoiliac occlusive disease underwent surgical treatment using FAT grafts. A piece of adipose connective tissue was obtained from the operative wound, cut into small pieces, and pressed into the wall of a fabric vascular prosthesis. Cumulative primary patency rates were 92% at 1 year, 92% at 3 years, and 86% at 6 years. Cumulative secondary patency rates were 96%, 96%, and 90% for the same intervals. In this clinical study, the FAT grafts demonstrated good long-term patency rates and no particular problems. This is the first clinical report of long-term outcomes using FAT grafts for aortofemoral or aortoiliac bypasses. FAT grafts are thus safe for revascularization in aortoiliac occlusive disease.  相似文献   
963.
目的 探讨终末期肝病模型(MELD)评分评估肝储备功能在原发性肝癌合并肝硬化脾功能亢进中确定手术适应证的应用价值.方法 对2001年1月至2007年1月间行肝癌切除联合脾切除(联合术)治疗的40例原发性肝癌合并肝硬化脾功能亢进患者的临床资料进行回顾性分析.通过MELD评分与Child-Pugh分级比较,结合临床资料及术后并发症分析,确定这一方法在评估肝储备功能中的作用.结果 同一Child-Pugh分级的患者MELD评分结果并不一致,在各级别间有交错现象.术后发生肝功能衰竭组(6例)的MELD评分均值为(24.6±6.6).未发生肝功能衰竭组(34例)的MELD评分均值为(16.3±8.5),差异有统计学意义(P<0.05).根据MELD评分分为A组16例(MELD评分<10),B组17例(MELD评分10-20),C组7例(MELD评分>20).A组术后肝功能衰竭发生率为0,B组为11.8%(2/17),C组为57.1%(4/7),差异有统计学意义(P<0.05).根据Child-Pugh分级分为Ⅰ级26例,Ⅱ级14例.Ⅰ级术后肝功能衰竭发生率为15.4%(4/26),Ⅱ级为14.3%(2/14),差异无统计学意义(P>0.05).结论 MELD评分能够较为客观地反映肝储备功能,对外科术式的选择、手术时机的确定有一定的参考作用.  相似文献   
964.
965.
We tested the hypothesis that serum factors present in Crohn's disease interfere with the process of lymphocyte activation. The mitogen-induced proliferation and the expression of early activation antigens by normal lymphocytes cultured in the presence of either Crohn's disease sera or sera from different controls were evaluated. The mitogen-induced proliferation was significantly impaired in the presence of Crohn's disease sera. These sera markedly inhibited the mitogen-induced interleukin-2 receptor (IL-2R) expression (48% inhibition), while the effect of sera on the expression of the transferrin receptor and the 4F2 antigen was much less pronounced. Diafiltration experiments showed that the inhibitory effect was confined to a 30-50-kD serum fraction. Such a serum property was not related to the patients' disease activity and disappeared after surgical removal of the affected bowel. The capability of inhibiting the mitogen-induced IL-2R expression was not restricted to Crohn's disease and was observed with sera from other inflammatory and neoplastic gastrointestinal disorders. This study indicates that a marked inhibition of the IL-2R is a mechanism underlying the immunosuppressive property of the serum in Crohn's disease and in other gastrointestinal conditions.  相似文献   
966.

Background

Since its sudden appearance and link to microcephaly in 2015, the number of PubMed references for Zika virus (ZIKV) has risen from 181 to 5163, at time of writing, with a vast proportion focused on the consequences of ZIKV infection during pregnancy. This level of attention underlies increased demand for sensitive and specific diagnostic tools able to assess risk to an unborn child, as well as to understand the dynamics and consequences of viral persistence.

Aim

Review the expanding knowledge on ZIKV persistence and diagnostic challenges and summarize current advancements in detection.

Sources

Peer-reviewed articles based on the search terms ‘Zika’ and ‘ZIKV’ combined with the terms ‘diagnostics’ ‘point-of-care diagnostics’ ‘viral load’ ‘persistence’ ‘detection’ ‘treatment’ ‘nucleic acid amplification testing’ ‘microsphere’ ‘PVRT’ ‘RVNT’ ‘RT-LAMP’ ‘NASBA’ SIBA’ ‘RPA’ ‘SHERLOCK’ ‘ELISA’, and ‘TMA’ as well as laboratory experience of the authors.

Content

Topics covered include the emergence of the ZIKV epidemic, pathogenesis of ZIKV infection, the nature of ZIKV persistence, complications in serological diagnosis, tried and novel diagnostic laboratory techniques, and a recent accounting of point-of-care testing (POCT) methods.

Implications

Surveillance and research in the case of ZIKV has shifted into a more rapid and coordinated worldwide directive than has occurred with most viral epidemics to date. The particular concentration of outbreaks in resource-limited settings increases the need for simple assays capable of reliable, inexpensive, high-throughput ZIKV diagnosis. This review serves to both catalogue current diagnostic options and consider their suitability at point-of-care.  相似文献   
967.
本实验用 4~ 5月龄和 15~ 16月龄的 app/ ps1dtg小鼠各 5只 ,同龄野生型小鼠每个年龄组各 5只 ,用β-NADPH组织化学染色显示神经元一氧化氮合酶活性 ,刚果红组织学染色显示神经炎性斑 ,无偏性体视学计量皮质和海马神经炎斑的总体积 ,研究神经元一氧化氮合酶活性在 app/ ps1双转基因 (app/ ps1dtg) AD模型小鼠大脑皮质和海马的异常分布 ,探讨其在该模型小鼠及 AD患者脑内病理改变中的作用。结果显示 ,n NOS阳性神经元在各组小鼠皮质和海马内的分布没有区别 ,4~ 5月龄 app/ps1dtg小鼠皮质和海马可见神经炎斑 (NP)和营养不良性 NOS阳性神经突 (DTN) ;15~ 16月龄 app/ ps1dtg小鼠皮质和海马内NP的体积分别是 4~ 5月龄 app/ ps1dtg小鼠皮质 NP的 5倍 (P<0 .0 0 5 )和 8倍 (P<0 .0 0 1) ;15~ 16月龄 app/ ps1dtg小鼠皮质内 DTN的体积明显增大 (P<0 .0 1) ;且伴有 NOS阳性神经元形态的改变及海马 CA1 区 NOS阳性神经元数量的减少 (P<0 .0 5 ) ,DTN的形成与 NP呈正相关关系 (r=0 .85 ,P<0 .0 5 )。本实验结果表明 ,app/ ps1dtg小鼠能够模拟 AD患者脑内 NOS阳性神经元的病理改变 ,DTN的形成可能与 Aβ的毒性作用有关 ,DTN产生的 NO可能参与 app/ ps1dtg小鼠和 AD的神经病理过程。  相似文献   
968.
Intraneuronal inclusions containing ubiquitylated filamentous protein aggregates are a common feature of many of the major human neurodegenerative disorders, including Alzheimer's and Parkinson's disease. Loss of function mutations in enzymes of the ubiquitin conjugation/deconjugation pathway are sufficient to cause familial forms of neurodegenerative diseases, suggesting that failure of ubiquitin-mediated proteolysis could also be central to inclusion formation in the more common sporadic cases. Examination of ubiquitin-positive inclusions at the protein level provides evidence of attempted proteasomal proteolysis, however close inspection of the temporal aspects of inclusion formation indicates that ubiquitylation is probably a late event. In this regard, the presence of ubiquitin within inclusions of idiopathic neurodegenerative disorders may indicate not a primary dysfunction of ubiquitin-mediated proteolysis, but rather a secondary, presumably protective cellular response. Within this model, other factors are likely to be initiating in inclusion biogenesis. Consistent with these proposals, non-ubiquitylated forms of the principal ubiquitylated components of Alzheimer's disease neurofibrillary tangles and Parkinson's disease Lewy bodies, tau and alpha-synuclein proteins, respectively, can be degraded by proteasomes in a pathway which does not have an absolute requirement for ubiquitylation. Inhibition of proteasome function in the pathological state, as has been reported in both Alzheimer's and Parkinson's disease, could therefore contribute both to accumulation of non-ubiquitylated forms of aggregation-prone neuronal proteins, as well as impaired clearance of ubiquitylated aggregates.  相似文献   
969.
目的探讨宫颈病变程度与人类乳头状瘤病毒(HPV)16、18型负荷的关系。方法采用实时荧光定量聚合酶链反应(FQ-PCR)方法,检测宫颈不同病变活检组织及石蜡包埋标本中HPV16、18型感染状况。结果正常宫颈上皮感染HPV16、18型阳性率为3%,CINⅠ、Ⅱ、Ⅲ级和宫颈癌感染HPV16、18阳性率分别为45.7%,69.5%,72.2%和74.6%。正常宫颈与CIN,宫颈癌HPV16、18阳性率差异有极显著性(P<0.0001)。宫颈糜烂(Ⅰ°、Ⅱ°、Ⅲ°),CIN(Ⅰ、Ⅱ、Ⅲ级)及鳞癌HPV16、18阳性标本平均拷贝数分别为:3.58×103、1.80×105、1.19×107,随着病变程度加重而逐渐增加,差异有极显著性(P<0.0001)。结论宫颈病变程度与HPV16、18型负荷呈正相关。对宫颈病变组织标本行HPV16、18型检测,对判断宫颈病变发展趋势,积极处理癌前病变,阻断病程、预防宫颈癌的发生将起到重要作用。  相似文献   
970.
Extracellular calreticulin (CRT) as well as anti‐CRT antibodies have been reported in patients with various autoimmune disorders and CRT has been implicated in ‘epitope spreading’ to other autoantigens such as the Ro/SS‐A complex. In addition, antibodies against parasite forms of the endoplasmic reticulum chaperone, CRT, have been found in patients suffering from onchocerciasis and schistosomiasis. In this study, we screened sera for anti‐CRT antibodies from patients with active and inactive systemic lupus ertythematosus (SLE) and primary or secondary Sjögren’s syndrome. Approximately 40% of all SLE patients were positive for anti‐CRT antibodies. The antigenic regions of CRT were determined using full length CRT and fragments of CRT prepared in yeast and Escherichia coli, respectively. Synthetic 15mer peptides corresponding to the major autoantigenic region of CRT (amino acids 1–289), each one overlapping by 12 amino acids, were used to map the B cell epitopes on the CRT protein recognized by autoimmune sera. Major antigenic epitopes were found to be associated with the N‐terminal half of the protein in 69% of the SLE sera from active disease patients, while the C‐domain was not antigenic. Major epitopes were found to be reactive with antibodies in sera from SLE patients with both active and inactive disease, spanning different regions of the N and P‐domains. Sera from both healthy and disease controls and primary Sjögren’s syndrome patients were non‐reactive to these sequences. Limited proteolysis of CRT with two major leucocyte serine proteases, elastase and cathepsin G, demonstrated that an N‐terminal region of CRT is resistant to digestion. Interestingly, some of the epitopes with the highest reactivity belong to the fragments of the protein which bind to C1q and inhibit complement activation. Whether C1q association with CRT is a pathological or protective interaction between these two proteins is currently under investigation.  相似文献   
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