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21.
The serious result of hepatitis B (HBV) virus infection is development of hepatocellular carcinoma (HCC). However, the reason of development of HCC in HBV infected patients is still unclear. Recently, the suppression of cell apoptosis is found to relate with the development of cell carcinogenesis, therefore, the expression of apoptosis inhibitor in the virus related cancer line such as hepatoma cell line HepG2.215 was investigated. There are at least six Human apoptosis inhibitors (IAP) have been identified now. They are cIAP1, cIAP2, XIAP, NAPI, survivin and pIAP. Using gene-assay technology, we have recently compared the expression of IAPs in the HepG2.215 cells that persistently expresses Hepatitis B virus by integrated HBV genome with its parent cell line HepG2. The results suggest that there was obviously increase of cIAP2 and cIAP1 in the HepG2.215 cells versus HepG2 cells. Those observations imply a possibility of long time HBV infection could induce the over-expressing apoptosis inhibitors, furthermore, causing the liver cancer. The high expression of cIAP1 and cIAP2 in HBV expressing cells was confirmed by RT-PCR and Northern blot analysis. However, we did not find the change of NIAP and suvivin in HepG2.215 cells. In contrast, the expression of XIAP was down in the HepG2.215 cells comparing with HepG2 cells. How HBV triggers the over-expression of apoptosis inhibitor is unclear. Transient transfection of HepG2 cells with the plasmids expressing different HBV proteins such as S, M, L, X and core proteins did not give a decisive conclusion. Further study is going on now.  相似文献   
22.
Controlled studies in clinical cancer research   总被引:2,自引:0,他引:2  
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23.
The Bioperl toolkit: Perl modules for the life sciences   总被引:36,自引:4,他引:36  
The Bioperl project is an international open-source collaboration of biologists, bioinformaticians, and computer scientists that has evolved over the past 7 yr into the most comprehensive library of Perl modules available for managing and manipulating life-science information. Bioperl provides an easy-to-use, stable, and consistent programming interface for bioinformatics application programmers. The Bioperl modules have been successfully and repeatedly used to reduce otherwise complex tasks to only a few lines of code. The Bioperl object model has been proven to be flexible enough to support enterprise-level applications such as EnsEMBL, while maintaining an easy learning curve for novice Perl programmers. Bioperl is capable of executing analyses and processing results from programs such as BLAST, ClustalW, or the EMBOSS suite. Interoperation with modules written in Python and Java is supported through the evolving BioCORBA bridge. Bioperl provides access to data stores such as GenBank and SwissProt via a flexible series of sequence input/output modules, and to the emerging common sequence data storage format of the Open Bioinformatics Database Access project. This study describes the overall architecture of the toolkit, the problem domains that it addresses, and gives specific examples of how the toolkit can be used to solve common life-sciences problems. We conclude with a discussion of how the open-source nature of the project has contributed to the development effort.  相似文献   
24.
Autologous bone harvested from the ilium is commonly used as a grafting material in surgical reconstructive and arthrodesis procedures to ensure a satisfactory postoperative outcome. However, operative removal of bone from the iliac crest requires an additional surgical procedure with a distinct set of postoperative complications. We provide a comprehensive literature synthesis of the incidence and severity of complications reported to be associated with this commonly practiced procedure. Most severe complications are rare, but chronic pain at the donor site exceeding three months in duration occurs frequently and can be particularly bothersome to patients. Alternative grafting materials that are safe and effective are sorely needed.  相似文献   
25.
目的研究喉癌中表皮生长因子受体(EGFR)基因的扩增、表达,探讨其在喉癌发生、发展中的作用及临床意义。方法采用差异PCR(differential PCR)方法检测40例喉鳞状细胞癌及配对癌旁正常组织中EGFR基因的扩增(即基因拷贝数增加);应用RT-PCR方法检测EGFR mRNA水平;应用SPSS13.0软件对数据进行统计学分析。结果喉癌组织中有13例(占32.5%)EGFR基因拷贝数增加,癌旁对照组中则未检测到(χ2=15.537,P<0.005);喉癌组织中EGFR mRNA平均积分光密度为872.356±62.340,癌旁对照组为346.425±57.380(t=5.959,P<0.001);喉癌组织分化程度越低,病理分期越晚,EGFR基因扩增和mRNA表达水平越高(P<0.05)。结论喉癌中EGFR基因在DNA水平上的扩增是EGFR mRNA过表达的原因之一,EGFR的扩增和过表达在喉癌的发生、进展中发挥一定作用。  相似文献   
26.
The toxicology of mercury   总被引:1,自引:0,他引:1  
Block LS 《The New England journal of medicine》2004,350(9):945-7; author reply 945-7
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27.
    
With the advent of automated anesthesia record keeping devices, concern has arisen that abnormal values will appear in the record and possibly lead to medicolegal compromise. A retrospective review of automated records from a series of anesthesia cases was undertaken to determine if abnormal values do occur, how frequent they are, and whether they cause problems. A total of 14,826 (4,942 each) noninvasive heart rate, systolic, and diastolic blood pressure readings from 118 case printouts generated by a Diatek Arkive Patient Information Management System (63 cases) or a Data-scope Datatrac record keeper (55 cases) were recorded. The study sample covered a broad range of surgical operations, anesthetic procedures, and patient ages and medical histories. During these 118 anesthetics, the majority of readings of all three variables fell within normal ranges (defined for this study as 80 to 180 and 50 to 110 mm Hg for systolic and diastolic blood pressures, respectively, and 60 to 140 beats/min for heart rate). During the anesthetics, 3.6% of the systolic pressure readings, 13.25% of the diastolic readings, and 4.25% of the heart rate readings were recorded outside these ranges. No serious intraoperative or postoperative anesthesia complications were associated with these out-of-range readings, nor would they be expected in a sample of this size, since serious anesthetic complications are rare. This preliminary observation of one person's experience may help address the concern associated with allowing high and low blood pressure and heart rate readings to be automatically recorded unsmoothed. In medicolegal situations, it should also begin to demonstrate that such fluctuations are neither uncommon nor abnormal, and that a true record of these readings should be neither a cause for concern nor an opportunity for medicolegal exploitation.  相似文献   
28.
This article reviews the results obtained on 262 VK partial and total temporomandibular joint (TMJ) procedures followed up to 10 years. VK I total joint (placed 1982 to 1986) cumulative success rate was 44% at 6 years and 20% at 10 years, while VK II (placed 1986 to 1990) cumulative success rate was 80% at 6 years. Material wear of the Teflon FEP surface of the VK I fossa was the most common reason for failure. There were no VK II material failures. A significant improvement in clinical success parameters for both prostheses was found if no previous surgeries were done before VK I or VK II total joint placement. Rib grafts were not helpful after removal of total joint prostheses if patients had a history of multiple procedures. Total TMJ prostheses must be reserved for patients with alternative surgical failures or when these procedures are no longer indicated. Close monitoring by clinical examination and imaging is necessary.  相似文献   
29.
Automated anesthesia recordkeepers have been used to monitor patients during surgery in up to 90% of cases at The Ohio State University. The record-keeping devices are complex and can be difficult to troubleshoot. The 1st-CLASS Fusion Program, an expert system shell-program, has been programmed to allow the resident or nurse anesthetist to solve the two most common types of problems associated with the recordkeeper: printer problems and patient monitor problems. Use of this program allows the resident or nurse anesthetist to troubleshoot the recordkeeper quickly and accurately and promotes in the user a sense of competence and control over the technology.  相似文献   
30.
Clinical and experimental data have indicated an up-regulation of amyloid precursor protein (APP) after various types of CNS injury. In the present study the cellular source of lesion-induced APP has been investigated an a neurotoxic CNS model. Quinolinic acid injection into the striatum results in neuronal degeneration, while glial cells survive. APP immunoreactivity was detected in glial cells starting at postoperative day 3 and persisted until day 21, the last time point studied. Double immunocytochemistry identified the majority of APP-immunoreactive cells as glial fibrillary acidic protein-immunoreactive astrocytes. There was no evidence of amyloid fibril deposition during this time. It is concluded that following excitotoxic neuronal degneration APP is mainly produced by reactive astrocytes in the lesioned area.  相似文献   
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