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61.
Summary Southern blot analysis of AvaI-digested total cellular DNA from the interfertile species Chlamydomonas eugametos and Chlamydomonas moewusii with a coxI mitochondrial gene probe from Chlamydomonas reinhardtii revealed single hybridizing fragments of 5.0 and 3.5 kb, respectively. The transmission of these mitochondrial DNA physical markers along with that of chloroplast genetic markers for resistance to streptomycin and resistance to erythromycin was studied in the fourth backcrosses of F1 hybrids to one or the other parent. Viability in these backcrosses is high in contrast to the cross C. eugametos x C. moewusii and its reciprocal which are associated with considerable meiotic product lethality. The resulting zygospores were found to transmit the mitochondrial and chloroplast genome markers uniparentally or preferentially from the mating-type-plus parent. Thus the species pair C. eugametos and C. moewusii differs from the pair Chlamydomonas reinhardtii and Chlamydomonas smithii in which mitochondrial genome markers are transmitted uniparentally by the mating-type minus parent, while the chloroplast genome markers are transmitted uniparentally by the opposite parental mating-type (Boynton et al. 1987). 相似文献
62.
F. Sessa E. Solcia C. Capella M. Bonato A. Scarpa G. Zamboni N. S. Pellegata G. N. Ranzani F. Rickaert G. Klöppel 《Virchows Archiv : an international journal of pathology》1994,425(4):357-367
Intraductal papillary growth of mucin producting hypersecreting, columnar cells characterizes a group of rare pancreatic exocrine neoplasms which we propose to call intraductal papillary-mucinous tumors (IPMT). We analysed the histopathology of 26 IPMT in relation to gastro-enteropancreatic marker expression, genetic changes and biology. Four IPMT showing only mild dysplasia were considered to be adenomas. Nine tumours displayed moderate dysplasia and were regarded as borderline. Severe dysplasia-carcinoma in situ changes were found in 13 IPMT which were therefore classified as intraductal carcinomas. Six of these carcinomas were frankly invasive and two of these had lymph node metastases. The invasive component resembled mucinous noncystic carcinoma in all but one tumour which showed a ductal invasion pattern. Immunohistochemically, an intestinal marker type was found in most carcinomas, while gastric type differentiation prevailed among adenomas or borderline tumours. K-ras mutations (seven at codon 12 and one at codon 13) were found in 31% of IPMT (2 adenomas, 1 borderline, 5 carcinomas). Nuclear p53 overexpression was detected in 31% of IPMT (6 carcinomas and 2 borderline IPMT) and correlated with p53 mutations (one at exon 8 and the other at exon 5) in two carcinomas. p53 abnormalities were unrelated to K-ras mutation. c-erbB-2 overexpression was observed in 65% of IPMT, with various grades of dysplasia. Twenty-two of 24 patients are alive and well after a mean post-operative follow-up of 41 months. Only two patients, both with invasive cancer at the time of surgery, died of tumour disease. It is concluded that pancreatic IPMT encompass neoplasms which, in general, have a favorable prognosis, but are heterogeneous in regard to grade of dysplasia and marker expression. Adenoma, borderline tumour, intraductal carcinoma and invasive carcinoma can be differentiated. p53 changes but not K-ras mutation or c-erbB-2 overexpression are related to the grade of malignancy. Most IPMT differ in histological structure, marker expression and behaviour from ductal adenocarcinoma. 相似文献
63.
中国东北汉族一个先天性白内障家系致病基因的鉴定 总被引:5,自引:0,他引:5
目的鉴定一个先天性白内障家系的致病基因。方法根据已知与先天性白内障有关的12个致病基因的染色体上的定位,分别选取3~4个的微卫星标记位点,对该家系进行连锁分析。通过测序鉴定致病基因。结果在1q21.1GJA8位点显示最大Lod值2.44。致病基因定位于1q21.1区的GJA8基因,构成缝隙连接的缝隙连接蛋白Connexin50。DNA序列分析鉴定显示其第2外显子的第191个碱基杂合突变T>G导致其蛋白产物第64位缬氨酸转变为甘氨酸。结论Connexin50的V64G新生突变是导致该家系的致病原因。 相似文献
64.
65.
本文提出在医学多模态数据集 (尤其是 MRI和 CT)中基于球形人造标记的体配准过程。此过程或是半自动或是全自动完成的。半自动方法要求数据集中标出球形标记的近似点位置 ,再自动进行配准。全自动方法不需要用户的任何交互操作 ,即所有配准子任务 (球体的分割、寻找两组球体的对应关系、最后把第一套球体映射成第二套球体的几何变换的计算 )能由计算机自动执行。在全自动配准中 ,积聚器算法和迭代最近点算法的结合证明是一种有效的和鲁棒性好的点匹配方法 相似文献
66.
Lida Bruni Barbara Angeletti Esterina Pascale Maria Cristina Tozzi Paola Giammaria Roberto Verna Ettore D'Ambrosio 《Clinical genetics》1996,50(2):89-92
Genotyping with flanking DNA markers was used to ascertain Treacher Collins Franceschetti syndrome (TCOF1) in a subject affected by tetralogy of Fallot and cryptorchidism. The proband's family consisted of a father and sister who were affected by the disease, and a healthy mother. Since cardiac malformation and cryptorchidism have been associated with the TCOF1 syndrome, the proband was suspected to be a carrier of the mutated gene. Microsatellite markers D5S527, SPARC and D5S519, which previously mapped the TCOF1 gene within a 2.1-cM interval on chromosome 5 (5q32–33.1), were used to follow the transmission of the TCOf 1 mutated locus. Flanking markers D5S519 and D5S527 were informative and enabled us to exclude inheritance of a TCOF1 mutation to the proband, while showing that cardiac malformation and cryptorchidism were unrelated in mis patient. 相似文献
67.
Two polymeric autosomal loci, Ten1 and Ten2, regulate thymus enlargement in BUF/Mna (B) rats. Previously, we mapped Ten1 on chromosome (Chr) 1 to a 20 cM region between Myl2 and D1Mgh11, and Ten2 on Chr 13. To further characterize the precise position of Ten1, 34 and 37 microsatellite markers, that have a polymorphism between the B and WYK (W) and between the B and MITE (M) strains, were used for linkage analysis of thymus enlargement in 105 (WBF1 x B) blackcross (BC) and 78 (B x BMF1) BC rats, respectively. Our data showed that the D1Rat168, D1Rat112, D1Rat323, D1Got186, D1Got187 and D1Got188 markers each gave a peak logarithm of odds (LOD) score of 10.68 for linkage to the thymus ratio in (WBF1 x B) BC rats, and that the D1Rat168, D1Rat197, D1Got184, D1Got186 and D1Got188 markers each gave a peak LOD score of 7.82 in (B x BMF1) BC rats. The two LOD score peaks are coincident in the position of the rat genetic map. All of the markers mentioned above are located in the region between Igf2 and D1Mgh11, in which synteny is conserved with human 11q15.5 and the distal end of mouse Chr 7 or with human 11q13 and the proximal end of mouse Chr 19. Genes existing in these regions are discussed as candidate genes for Ten1. 相似文献
68.
肺癌患者血清TSGF、CEA、CYFRA21—1和NSE水平的临床价值 总被引:1,自引:2,他引:1
目的:探讨血清TSGF、CEA、CYFRA21-1和NSE水平的临床价值。方法:采用放射免疫分析测定了179例肺癌、48例肺良性病变和51例正常对照组的血清TSGF、CEA、CYFRA21-1和NSE的水平。结果:在NSCLC中,37例I~II期鳞癌血清中TSGF、CEA和NSE水平与肺良性病变无明显差异(P均>0.05),32例I~II期腺癌血清中NSE也与肺良性病变无明显差异(P>0.05);其余,NSCLC和SCLC血清中TSGF、CEA、CY-FRA21-1和NSE水平明显增高,均与肺良性病变具有明显差异(P<0.05~0.01),从总体而言,随着病变的严重程度增加,肺癌标志物水平也增高。51例正常对照组血清TSGF、CEA、CYFRA21-1和NSE水平分别为(64.1±14.8)U/ml,(3.51±1.1)ng/ml,(2.6±1.4)ng/ml和(5.1±3.6)ng/ml。结论:肺癌的诊断中,以血清CY-FRA21-1测定为最佳,其次为TSGF和CEA,最差NSE,故肺癌标志物的联检是诊断肺癌的最佳选择。 相似文献
69.
目的:探讨HBV—DNA阳性育龄妇女病毒复制与HBV标志物及前S1抗原的关系。方法:对1643例慢性乙型肝炎育龄妇女采用荧光定量PCR法检测血清HBV—DNA,酶联免疫吸附法(ELISA)检测HBV标志物和前S1抗原。结果:HBV—DNA阳性育龄妇女432例。其中,HBsAg阴性者占19.44%,前S1抗原总阳性率55.09%,且随着HBV—DNA载量增加,前S1抗原阳性率也升高。结论:采用HBV—DNA、HBV标志物、前S1抗原联检,才能更准确提供育龄妇女HBV感染诊疗依据,有效控制HBV感染率。 相似文献
70.
Markers of cartilage degradation hold a great, but so far underutilized potential in the research and clinical management of joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA). With the rapid pace of development of such markers, they are likely to emerge as promising clinical tools for several uses. These roles may include: improving preclinical and clinical development in arthritis research; differentiation of patients with high and low turnover states at disease diagnosis; selection of optimal therapy and therapy dose for the individual patient; monitoring disease progression; and predicting disease outcome.This review focuses on the cartilage matrix components and the metabolites from this very special tissue that have been proposed as biochemical markers. Special attention is focused on the challenges facing the development of such markers to the standards required for widespread practical use. Examples are provided on the current use of cartilage derived biochemical markers and perspectives for the future use of markers and required clinical documentation are presented. 相似文献