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991.
Knowing Ron     
Spechko  Phyllis L. 《JAMA》2006,296(7):738
  相似文献   
992.
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   
993.
The incidence of uterine cervical cancer has increased slightly in Western countries, with an increase in relatively young women. Overexpression of matrix metalloproteinases (MMPs)-2 and -9 has turned out as a prognostic factor in many cancers. We compared the expression of the proteins MMP-2 and MMP-9 in cervical primary tumors with clinical outcome and risk factors of cervical cancer. One hundred sixty-one patients with cervical cancer treated in Ume? University Hospital or Sahlgrenska University Hospital, Sweden, between 1991 and 1995 were included in the study. Paraffin-embedded tissue samples obtained prior to treatment were examined immunohistochemically by specific antibodies for MMP-2 and MMP-9. Forty-two percent of the tumors were intensively positive for MMP-2 and 31% for MMP-9. Nineteen percent of the samples were intensively positive for both proteinases and 47% negative or weak for both. Overexpression of MMP-2 seemed to predict unfavorable survival under Kaplan-Meier analysis and in the multivariate analysis. Early sexual activity and low parity seemed to correlate to overexpression of MMP-2. MMP-9 was not associated with survival or sexual behavior. Intensive MMP-9 was noted in grade 1 tumors. We conclude that MMP-2 and MMP-9 have different roles in uterine cervical cancer. MMP-2 could be associated with aggressive behavior, but MMP-9 expression diminishes in high-grade tumors.  相似文献   
994.
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   
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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   
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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   
1000.
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