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排序方式: 共有10000条查询结果,搜索用时 20 毫秒
941.
942.
I. DIMOVA B. ZAHARIEVA S. RAITCHEVA† R. DIMITROV‡ N. DOGANOV‡ & D. TONCHEVA 《International journal of gynecological cancer》2006,16(1):145-151
The objective of this study was to assess the implication of copy number changes of epidermal growth factor receptor (EGFR) and erbB2 genes in the etiology and progression of ovarian tumors. In our study, we used the highly reliable method of fluorescent in situ hybridization, applied on tissue microarray, containing 1006 ovarian tumors from different malignancy, histologic type and grade, and tumor stage, in order to analyze the correlations between gene copy number changes and tumor phenotype. We established copy number changes of erbB2 in 15.30% of malignant ovarian tumors-8.16% amplifications and 7.14% gains. The frequency of EGFR copy number changes was 10.67%-3.65% amplifications and 7.02% gains. EGFR gains occurred with approximately the same frequency in malignant (7.02%), low malignant potential (8.33%), and benign (7.19%) ovarian tumors. ErbB2 amplification was associated with clear cell type of ovarian cancer (P < 0.04). No amplification of EGFR and erbB2 genes was established in tumors with low malignant potency and in benign tumors. Regarding cancer phenotype, there was no statistically significant association between erbB2 copy number changes and histologic grade as well as tumor stage of ovarian cancer. EGFR gains are early events in ovarian tumorigenesis. Our results showed similar frequencies of EGFR gains in different grade tumors, while EGFR amplification increased from grades 1 to 2 to 3. 相似文献
943.
X chromosomal and autosomal loss of heterozygosity and microsatellite instability in human cervical carcinoma 总被引:1,自引:0,他引:1
J. EDELMANN K. RICHTER C. HÄNEL† S. HERING‡ & L.-C. HORN† 《International journal of gynecological cancer》2006,16(3):1248-1253
The study analyzes tumor material and normal tissue from 27 patients with pure squamous cell carcinoma of the uterine cervix for loss of heterozygosity (LOH) and microsatellite instability (MSI) on 14 autosomal and 11 X chromosomal loci. Overall, 4-40% of the informative cases showed LOH at autosomal regions with the highest frequency at 3p (21-40%) and a marked frequency at 2q35-q37.1 (12.5%) and 17p13.3 (10%), representing regions with putative tumor suppressor gene (TSG) function. The frequency of X chromosomal LOH ranged from 4% to 20%, with a maximum at Xq28 (20%) and Xq11.2-q12 (17%), again indicating alterations in TSG. A 12% LOH was seen at Xq21.33-q22.3, a region encoding a protein with a regulatory function in the cell cycle via cyclin-dependent kinases. MSI was detected in autosomal regions in up to 7% in regions linked to the X chromosome in up to 11%, probably indicating alterations of mismatch repair mechanisms. Our results and those obtained from the literature suggest that autosomal LOH and MSI in carcinomas of the cervix uteri are predominantly found at regions with putative TSG function. Beside TSG alterations, X chromosomal LOH is probably more strongly connected to disturbances in cell cycle regulation. 相似文献
944.
945.
In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain. 相似文献
946.
947.
Adalberto Parra Jorge Ramírez-Peredo Rocío Hidalgo Amelia Morales-Toquero Gabriela Velásquez-Ramírez Alejandro Ruiz-Argüelles Guillermo J Ruiz-Argüelles 《Biology of blood and marrow transplantation》2006,12(5):566-572
We compared the functional status of the hypothalamic dopaminergic tone in patients given an allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (GVHD) with that observed in patients with allo-HSCT without chronic GVHD and in healthy controls. The effect of acute dopaminergic blockade with intravenous metoclopramide on serum prolactin (PRL) concentrations was evaluated. Twenty volunteers, 20 to 52 years of age, seronegative for both hepatitis C virus and the human immunodeficiency virus, were studied: (1) 10 clinically healthy men (group 1), and (2) 9 patients with leukemia, and 1 patient with refractory aplastic anemia who underwent allo-HSCT, 5 of whom (3 men and 2 women) developed chronic GVHD (group 2), and 5 (3 men and 2 women) who did not develop chronic GVHD (group 3). Serum PRL concentrations were measured both fasting and after intravenous administration of metoclopramide (10-mg bolus). The area under the PRL curve was calculated. Patients in group 2 were older than those in groups 1 and 3 (P<.018), but their body mass index was similar. Fasting serum PRL concentrations were similar among the 3 groups; however, group 2 had higher PRL concentrations throughout the test (P<.001) and a greater area under the PRL curve than groups 1 and 3 (P<.001), without differences between the last 2 groups. The differences remained significant after adjustment for age (P<.01). Our results in a small group of patients with chronic GVHD after allo-HSCT suggest the existence of an increased functional level of their hypothalamic dopamine tone, which would favor a tendency toward a diminished endogenous production, release of pituitary PRL, or both. This could represent an adaptive mechanism aiming to maintain circulating PRL concentrations within a physiological range. 相似文献
948.
A. G. G. Lødeng C. Ahlén H. Lysvand L. H. Mandal O. J. Iversen 《Clinical microbiology and infection》2006,12(8):761-768
This report describes a new PCR-based assay for the detection of Pseudomonas aeruginosa genotype D in occupational saturation diving systems in the North Sea. This genotype has persisted in these systems for 11 years (1993-2003) and represents 18% of isolates from infections analysed during this period. The new PCR assay was based on sequences obtained after randomly amplified polymorphic DNA (RAPD)-PCR analysis of a group of isolates related to diving that had been identified previously by pulsed-field gel electrophoresis (PFGE). The primer set for the D genotype targets a gene that codes for a hypothetical class 4 protein in the P. aeruginosa PAO1 genome. A primer set able to detect P. aeruginosa at the species level was also designed, based on the 23S-5S rDNA spacer region. The two assays produced 382-bp and 192-bp amplicons, respectively. The PCR assay was evaluated by analysing 100 P. aeruginosa isolates related to diving, representing 28 PFGE genotypes, and 38 clinical and community P. aeruginosa isolates and strains from other species. The assay identified all of the genotype D isolates tested. Two additional diving-relevant genotypes (TP2 and TP27) were also identified, as well as three isolates of non-diving origin. It was concluded that the new PCR assay is a useful tool for early detection and prevention of infections with the D genotype. 相似文献
949.
Susan M Domchek Andrea Eisen Kathleen Calzone Jill Stopfer Anne Blackwood Barbara L Weber 《Journal of clinical oncology》2003,21(4):593-601
Breast cancer risk assessment provides an estimation of disease risk that can be used to guide management for women at all levels of risk. In addition, the likelihood that breast cancer risk is due to specific genetic susceptibility (such as BRCA1 or BRCA2 mutations) can be determined. Recent developments have reinforced the clinical importance of breast cancer risk assessment. Tamoxifen chemoprevention as well as prevention studies such as the Study of Tamoxifen and Raloxifene are available to women at increased risk of developing breast cancer. In addition, specific management strategies are now defined for BRCA1 and BRCA2 mutation carriers. Risk may be assessed as the likelihood of developing breast cancer (using risk assessment models) or as the likelihood of detecting a BRCA1 or BRCA2 mutation (using prior probability models). Each of the models has advantages and disadvantages, and all need to be interpreted in context. We review available risk assessment tools and discuss their application. As illustrated by clinical examples, optimal counseling may require the use of several models, as well as clinical judgment, to provide the most accurate and useful information to women and their families. 相似文献
950.