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991.
Cultured rat sympathetic neurons die within 48 h after being deprived of nerve growth factor. Addition of interferons (IFN-alpha/beta or IFN-gamma) prevented the cell death in a dose-dependent manner. Upon longer periods of nerve growth factor deprivation, IFNs failed to maintain survival. Thus, IFNs retarded neuronal death, but did not prevent it. Ligand binding, autoradiography, and cross-linking experiments demonstrated the presence of specific IFN-gamma receptors on sympathetic neurons similar to those seen on other cell types. The possible relationships of the death-suppressing actions of IFNs are compared to the mechanisms of the antiviral or antiproliferative actions of IFNs.  相似文献   
992.
Aims and objective: The Technical External Quality Assessment Scheme (TEQA) introduced in Wales is based on NHSCSP publication No 19 [External Quality Assessment Scheme for the Evaluation of Papanicolaou Staining in Cervical Cytology] which sets out the policies and standard operating procedures for the TEQA of Papanicolaou staining of gynaecological cervical samples. As part of a development plan for the TEQA scheme in Wales, the use of a control sample was introduced to the assessment process – a common control sample can provide a consistent assessment parameter independent of the recommended slide selection process [External Quality Assessment Scheme for the Evaluation of Papanicolaou Staining in Cervical Cytology, NHSCSP Publication No 19, February 2004] enabling direct comparison of staining standards for laboratories within the region; this counters selection variation bias, establishing a process that may be more representative of routine staining results. Methods: A cervical sample was selected in line with the criteria described in publication 19 [External Quality Assessment Scheme for the Evaluation of Papanicolaou Staining in Cervical Cytology, NHSCSP Publication No 19, February 2004]. Thirteen slides were prepared by the scheme facilitator from this anonymized sample. These control slides were subsequently ‘fixed’ but not stained, then distributed to the laboratories participating in the TEQA scheme. The slides were stained using their standard regime, then returned to the facilitator for assessment. The slides showed consistent staining with no significant inter‐laboratory variation, however, the eosinophilic stained components exhibited an artificial colouration, which slightly altered the expected stained appearance; this was thought to be due to ‘cross‐reactivity’ of the spray fixative with the preserving agent. To address this artefact, a further development of control procedures was devised utilizing a pooled control sample procedure. Residual material from a number of similar samples was pooled and distributed in aliquots to participant laboratories for standard processing and staining; the completed slides were returned to the scheme facilitator for assessment. Results: The pooled sample slides were assessed at the next scheduled quarterly TEQA assessment. The overall scoring for these samples produced an acceptable level of Papanicolaou staining for 12 of the laboratories – only one laboratory produced a marginal score. The artefactual presentation of eosinophilia was not seen. Discussion/conclusion: This method of producing control material establishes consistency in the TEQA comparative assessment process, counters selection bias and reduces the time demands associated with slide selection. It may also prove useful in identifying technical problems within laboratories during sample preparation prior to or during staining, including equipment or process faults. This technique is now well established locally as an enhancement of the current TEQA scheme for the assessment of slide staining. We feel that this enhancement could be incorporated as a new initiative in the current National TEQA scheme as a complement to the established selection process.  相似文献   
993.
新疆南部维吾尔族聚居区是宫颈癌高发区. 本文旨在利用基因芯片技术筛选与维吾尔族妇女宫颈癌发生相关的基因. 首先,分别提取5例新疆维吾尔妇女宫颈癌和5例子宫肌瘤组织(对照)的mRNA,逆转录成cDNA,并用Cy3-dUTP标记子宫肌瘤组织的cDNA,用Cy5 dUTP标记宫颈癌组织的cDNA,制成芯片杂交探针.为筛选出宫颈癌组织中差异表达的基因,上述标记探针分别与含有20 000条人类基因的Affymetrix基因芯片进行杂交,杂交信号用GeneChip Scanner 3000扫描仪扫描,并用芯片图像分析软件(SAM software)分析扫描结果.筛选出的差异表达基因经GO(Gene Ontology)分析和KEGG(Kyoto Encyclopedia of Genes and Genomes)信号通路分析,确定其在宫颈癌中的作用.基因芯片筛选结果显示,在宫颈癌组织中发现2 758个差异表达基因,其中1 326个上调基因,1 432个下调基因.GO分析和KEGG信号通路分析表明,表达差异在两倍以上的基因涉及168个信号通路,包括细胞粘附分子、细胞周期以及MAPK和mTOR信号通路等.上述结果表明,基因芯片技术筛选出大量与宫颈癌发生相关的基因,其中表达差异显著的基因涉及细胞粘附分子、细胞周期和mTOR等信号通路.  相似文献   
994.
The docking protein FRS2α is an important mediator of fibroblast growth factor (FGF)-induced signal transduction, and functions by linking FGF receptors (FGFRs) to a variety of intracellular signaling pathways. We show that the carotid body is absent in FRS2α2F/2F mice, in which the Shp2-binding sites of FRS2α are disrupted. We also show that the carotid body rudiment is not formed in the wall of the third arch artery in mutant embryos. In wild-type mice, the superior cervical ganglion of the sympathetic trunk connects to the carotid body in the carotid bifurcation region, and extends thick nerve bundles into the carotid body. In FRS2α2F/2F mice, the superior cervical ganglion was present in the lower cervical region as an elongated feature, but failed to undergo cranio-ventral migration. In addition, few neuronal processes extended from the ganglion into the carotid bifurcation region. The number of carotid sinus nerve fibers that reached the carotid bifurcation region was markedly decreased, and baroreceptor fibers belonging to the glossopharyngeal nerve were absent from the basal part of the internal carotid artery in FRS2α2F/2F mutant mice. In some of the mutant mice (5 out of 14), baroreceptors and some glomus cells were distributed in the wall of the common carotid artery, onto which the sympathetic ganglion abutted. We propose that the sympathetic ganglion provides glomus cell precursors into the third arch artery derivative in the presence of sensory fibers of the glossopharyngeal nerve.  相似文献   
995.
小鼠脊髓重与颈膨大截面积QTL研究   总被引:2,自引:0,他引:2  
应用近交系小鼠A/J和C5 7BL/ 6J以及其F2 代重组小鼠定位脊髓重与颈膨大截面积数量性状基因座(QuantitativeTraitLoci,QTL)。结果表明 13个QTL与脊髓重和截面积相关 ,这些QTL分别位于 2、4、8、14、15、17、18、19和X染色体上。其中 6个QTL与脊髓重相关 ;4个QTL与颈膨大截面积相关 ;3个QTL与二者均相关。在 13个QTL中 ,3个QTL (P <0 0 1)———SC1(位于D15Mit15 8附近 )、SC2 (DXMit14 0附近 )和SC3(DXMit6 4附近 )其表型变异的解释率分别为 2 4 %、19%和 15 % ;加性效应分别为 - 3 78、3 4 1和 2 0 6mg。其他QTL的P值在 0 0 1~ 0 0 5之间。在上述 3个QTL中 ,SC1是唯一与脊髓重和面积均相关的QTL  相似文献   
996.
太行山猕猴第Ⅶ颈椎变量的异速生长分析   总被引:1,自引:1,他引:0  
以肱骨最大长为参照,对成年太行山猕猴第Ⅶ颈椎变量进行了异速生长分析。结果表明,椎体后高、椎体上矢径、全宽呈正异速生长;椎体下横径接近等速生长;椎体前高、椎体下矢径、椎体上横径、椎孔矢径、椎孔横径、矢径呈负异速生长。  相似文献   
997.
P_(53)突变、表达及人乳头状瘤病毒感染与宫颈癌   总被引:2,自引:0,他引:2  
利用免疫组化、聚合酶链反应(PCR)、单链构象多态性(SSCP)分析等方法, 对49例同一标本宫颈癌组织中p53蛋白、P53外显子7~8变异、HPV6、11、16、18-DN A进行检测,以探讨它们在宫颈癌形成中的作用、相互关系和临床意义.结果表明: a.P5 3基因外显子7~8突变率14.29%、p53蛋白阳性率48.98%、HPV-DNA阳性率87.76%.b.P53基因突变不一定伴有p53蛋白阳性,但P53基因突变而p53蛋白阴性的标 本必是HPV-DNA阳性;91.67%的p53蛋白阳性标本具有HPV-DNA阳性.c.HPV16-DNA阳 性率显著高于HPV6、11、18-DNA阳性率.证明:宫颈癌的发生主要与HPV16感染有关,其 次是P53基因突变所致;p53蛋白阳性由HPV感染和/或P53基因突变所致.  相似文献   
998.
999.
The BSCC terminology was originally published in 1986 and although highly successful, requires revision. Through a process of professional consensus and literature review this has been undertaken by the BSCC. The revision takes account of recent developments and improvements in understanding of morphology and disease process and is compatible with other terminologies in use elsewhere, whilst still maintaining a focus on practice in the UK cervical screening programmes.  相似文献   
1000.
Objective:  To establish whether women with low-grade abnormalities detected during screening for cervical cancer prefer to be managed by cytological surveillance or by immediate colposcopy.
Methods:  TOMBOLA (Trial of Management of Borderline and Other Low-grade Abnormal smears) is a randomized controlled trial comparing alternative management strategies following the screen-detection of low-grade cytological abnormalities. At exit, a sample of TOMBOLA women completed a questionnaire eliciting opinions on their management, contingent valuations (CV) of the management methods and preferences. Within-trial quality of life (EQ-5D) data collected for a sample of TOMBOLA women throughout their follow-up enabled the comparison of self-reported health at various time points, by management method.
Results:  Once management had been initiated, self-reported health in the colposcopy arm rose relative to that in the surveillance arm, although the effect was short-term only. For the majority of women, the satisfaction ratings and the CV indicated approval of the management method to which they had been randomized. Of the minority manifesting a preference for the method which they had not experienced, relatively more would have preferred colposcopy than would have preferred surveillance.
Conclusions:  The findings must be interpreted in the light of sample bias with respect to preferences, whereby enthusiasm for colposcopy was probably over-represented amongst trial participants. The study suggests that neither of the management methods is preferred unequivocally; rather, individual women have individual preferences, although many would be indifferent between methods.  相似文献   
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