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941.
942.
943.
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   
944.
The purpose of this study was to predict lymphatic involvement in endometrial cancer using clinicopathologic variables of patients treated with surgical staging. Overall, 461 patients treated with an initial surgical staging procedure including complete pelvic-para-aortic lymphadenectomy were included. The mean number of resected lymph nodes was 27 (median 26; range 15-83), and 54 patients (12%) had lymphatic involvement. Of these patients, 32 had only pelvic, 15 had both pelvic and para-aortic, and 7 had isolated para-aortic metastases. In the multivariate analysis, deep myometrial invasion (P= 0.02), lymphvascular space invasion (P= 0.001), positive peritoneal cytology (P= 0.002), and cervical involvement (P= 0.003) predicted retroperitoneal lymph node metastasis (RLN) significantly. Two hundred seventy-four patients (59.4%) had at least one of these poor prognostic factors identified by multivariate analysis. In this patient population, 53 (19.3%) had lymphatic involvement compared to 1 patient in the group of 187 patients with low-risk criteria. Ninety-eight percent of patients with RLN were predicted by this model, and with the advent of accurate diagnostic techniques, 40% of patients could be saved from undergoing lymphadenectomy.  相似文献   
945.
946.
PURPOSE: A genetics evaluation of children with pervasive developmental disorders (PDDs) identifies a diagnosis in 6% to 15% of cases. However, previous studies have not measured the incidence of genetic disorders among children with autistic-like features who do not necessarily meet the Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition criteria for PDD. METHODS: We identified 101 patients at our institution referred for PDD, autism, Asperger syndrome, or autistic features. Seventy-eight were males and 23 were females, giving a male-to-female ratio of 3.4:1. No diagnosis was identified on examination alone, although Rett syndrome was suspected in six females. Seventeen patients did not undergo any type of testing because of noncompliance. RESULTS: Of the remaining 84 patients analyzed, seven (8.3%) were found to have abnormalities on testing. Three chromosomal anomalies were found: one with 5p duplication, one with low-level mosaicism for trisomy 21, and one with an unbalanced 10;22 translocation. Three females were diagnosed with Rett syndrome after MECP2 analysis identified a disease-causing mutation. The remaining patient was found to have an elevated urine orotic acid, with a normal ammonia level, of unknown significance. CONCLUSION: On the basis of our series, the yield of a genetics evaluation in patients with features of PDD who do not necessarily meet the Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition criteria is 8.3%. Approximately half of these were the result of a chromosomal abnormality. Three cases of Rett syndrome were identified for which autistic behaviors are a well-described feature. These findings suggest that a high-resolution karyotype provides the greatest diagnostic yield for patients with autistic-like features. MECP2 analysis should be considered for females who present with autistic behaviors.  相似文献   
947.
The main objectives of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) are to harmonise breakpoints for antimicrobial agents in Europe, and to act as the breakpoint committee for the European Medicines Agency (EMEA) during the registration of new antimicrobial agents. Detailed EUCAST procedures for harmonising and setting breakpoints for antimicrobial agents are available on the EUCAST website. Beginning with the current issue, a series of EUCAST Technical Notes will be published in CMI, based on the rationale documents produced by EUCAST for each of the antimicrobial agents studied, with the aim of highlighting important background information underlying decisions on breakpoints made by EUCAST.  相似文献   
948.
949.
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   
950.
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