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941.
TheenvelopeproteinofhepatitisBvirus(HBV)consistsofthreeproteins:small(S),middle(M)andlarge(L)[1].TheSproteincarriesalltheinformationrequiredforcellularlipidsmobilization,subviralparticleformationandsecretion.Ithasbeensuccessfullydevelopedasacarriertoexpressf…  相似文献   
942.
掌握百色市乙型肝炎疫苗纳入儿童免疫规划后的免疫效果,客观评价免疫规划工作现状。方法按现况研究原理,全市12个县(区),每个县(区)各抽取150名儿童,每个县在东、西、南、北、中五个方位随机抽取5个行政村,每个行政村抽取6个年龄组(1~6岁儿童),每个年龄组抽取5名常住儿童(当地居住三个月以上),收集血清样本进行乙肝病毒感染相关标志表面抗原及抗体检测。结果全市共调查1~6岁儿童1 809名儿童,乙肝表面抗原携带率为0.66%,低于2006年全国调查的1~4岁人群乙肝表面抗原携带率(0.96%),达到中国《2006—2010年全国乙型病毒性肝炎防治规划》提出的5岁以下儿童乙肝表面抗原携带率<1%的控制目标要求;1~6岁儿童乙肝表面抗体阳性率为77.77%,高于2006年全国调查的1~4岁人群乙肝抗体阳性率(71.24%)。结论百色市自2003年将乙肝疫苗纳入免疫规划管理后,乙肝免疫效果显著,乙肝病毒表面抗原阳性率大幅度下降,婴幼儿体内保护性抗体水平也高于全国水平。加强对孕产妇住院分娩率和婴幼儿乙肝疫苗接种工作,尤其是乙肝疫苗首针及时接种是今后乙肝预防控制的重点。  相似文献   
943.
目的:探讨p16基因在由乙型肝炎病毒基因整合引起的小鼠肝细胞癌发生发展中的表达变化规律。方法:以乙肝病毒表面抗原基因(HBsAg)及X基因(HBx)定位整合转基因小鼠及对照小鼠的肝脏组织为标本,利用North-ern印迹、Western印迹及免疫组织化学检测p16在乙肝病毒基因定位整合转基因小鼠肝脏正常组织与肿瘤组织中的差异表达。结果:p16主要在小鼠胚胎期的肝脏中表达,在新生小鼠和成年小鼠的肝脏组织中几乎检测不到其表达;在HBsAg转基因小鼠和HBx转基因小鼠的肝脏肿瘤中,p16的表达明显升高。结论:p16基因在HBsAg或HBx诱导的肝细胞癌发生过程中被重新激活,也许发挥重要的作用。  相似文献   
944.

Aims

Enterocytozoon hepatopenaei is an emerging microsporidian parasite that has been linked to recent losses caused by white faeces syndrome (WFS) in cultivated giant or black tiger shrimp Penaeus (Penaeus) monodon and whiteleg shrimp Penaeus (Litopenaeus) vannamei in Asia. To more accurately assess its impact on shrimp production and to determine reservoir carriers for control measures, our objective was to establish a loop‐mediated isothermal amplification (LAMP) assay combined with colorimetric nanogold (AuNP) for rapid, sensitive and inexpensive detection of this parasite.

Methods and Results

A set of six specific primers was designed to successfully detect the SSU rRNA gene of E. hepatopenaei by a LAMP reaction of 45 min at 65°C combined with visual detection of the amplification product via hybridization at 65°C for 5 min with a ssDNA‐labelled nanogold probe, followed by salt‐induced AuNP aggregation (total assay time, approximately 50 min). This method gave similar results to LAMP followed by electrophoresis or spectrophotometric detection, and it was more sensitive (0·02 fg total DNA) than a conventional nested PCR (0·2 fg total DNA). The new method gave negative results with shrimp DNA templates extracted from diseased shrimp containing other pathogens, indicating that the LAMP‐AuNP assay was specific for E. hepatopenaei.

Conclusions

Without sacrificing sensitivity or specificity, the new LAMP‐AuNP assay significantly reduced the time, ease and cost for molecular detection of E. hepatopenaei in shrimp.

Significance and Impact of the study

The new method employs simple, inexpensive equipment and involves simple steps making it applicable for small field laboratories. Wider application of the method to screen broodstock before use in a hatchery, to screen postlarvae before stocking shrimp ponds, to test for natural carriers and to monitor shrimp in rearing ponds would help to assess and reduce the negative impact of this parasite in shrimp farming.  相似文献   
945.
Traumatic injury to the brain or spinal cord and multiple sclerosis (MS) share a common pathophysiology with regard to axonal demyelination. Despite advances in central nervous system (CNS) repair in experimental animal models, adequate functional recovery has yet to be achieved in patients in response to any of the current strategies. Functional recovery is dependent, in large part, upon remyelination of spared or regenerating axons. The mammalian CNS maintains an endogenous reservoir of glial precursor cells (GPCs), capable of generating new oligodendrocytes and astrocytes. These GPCs are upregulated following traumatic or demyelinating lesions, followed by their differentiation into oligodendrocytes. However, this innate response does not adequately promote remyelination. As a result, researchers have been focusing their efforts on harvesting, culturing, characterizing, and transplanting GPCs into injured regions of the adult mammalian CNS in a variety of animal models of CNS trauma or demyelinating disease. The technical and logistic considerations for transplanting GPCs are extensive and crucial for optimizing and maintaining cell survival before and after transplantation, promoting myelination, and tracking the fate of transplanted cells. This is especially true in trials of GPC transplantation in combination with other strategies such as neutralization of inhibitors to axonal regeneration or remyelination. Overall, such studies improve our understanding and approach to developing clinically relevant therapies for axonal remyelination following traumatic brain injury (TBI) or spinal cord injury (SCI) and demyelinating diseases such as MS.  相似文献   
946.
947.
New treatments and new drugs for avian influenza virus (AIV) infection are developed continually, but there are still high mortality rates. The main reason may be that not all cell death pathways induced by AIV were blocked by the current therapies. In this review, drugs for AIV and associated acute respiratory distress syndrome (ARDS) are summarized. The roles of antioxidant (vitamin C) and multiple immunomodulators (such as Celecoxib, Mesalazine and Eritoran) are discussed. The clinical care of ARDS may result in ischemia reperfusion injury to poorly ventilated alveolar cells. Cyclosporin A should effectively inhibit this kind of damages and, therefore, may be the key drug for the survival of patients with virus-induced ARDS. Treatment with protease inhibitor Ulinastatin could also protect lysosome integrity after the infection. Through these analyses, a large drug combination is proposed, which may hypothetically greatly reduce the mortality rate.  相似文献   
948.
949.
目的:探讨灯盏细辛口服液对急性冠状动脉综合征患者外周血C-反应蛋白、1-甲基环丙烯和9-基质金属蛋白酶水平的影响。方法:选取我院心内科已确诊为急性冠状动脉综合征的患者110例,随机分为实验组和对照组,对照组行常规药物治疗,实验组在对照组的基础上口服灯盏细辛口服液。比较两组患者治疗前后外周血C-反应蛋白变化情况及MCP-1及MMP-9水平及临床疗效。结果:与治疗前相比,两组患者治疗后MCP-1、MMP-9及C-反应蛋白水平降低(P0.05),与对照组相比,实验组患者MCP-1、MMP-9及C-反应蛋白较低(P0.05);与对照组相比,实验组总有效率较高(P0.05)。结论:灯盏细辛口服液对急性冠状动脉综合征患者具有较好的疗效,这可能与其降低外周血中C-反应蛋白、MMP-9和MCP-1水平具有一定的关系。  相似文献   
950.
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