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61.
Abstract: Several clinicopathologic variables influence prognosis in breast cancer, including stage, histologic grade, nodal status, and tumor size. Multiple studies have shown an independent value of proliferation index as a prognostic variable for the stratification into favorable and unfavorable groups. The monoclonal antibody MIB-1 reacts with the same antigen site, not epitope, as recognized by the Ki-67 antibody. Like Ki-67, MIB-1 reacts with cells in the late G1, S, M and G2 phases of the cell cycle, but MIB-1 has the advantage of reacting with formalin-fixed, paraffin-embedded material. The authors investigated the feasibility of using image analysis to quantitate the MIB-1 antibody staining (proliferation index [PI]) and predict survival in a series of 230 patients with stage I and stage II breast cancer. In a univariate Cox regression model, larger values of MIB-1 were related to shorter survival times (p < 0.001). Exploratory statistical procedures were used to categorize the patients into good, intermediate, and poor survival groups using the following proliferation indices as cut-points: <5%, 5–11%, and >11 %, respectively. Higher clinical stage was associated with higher MIB-1 values and shorter survival (p = 0.01, and p = 0.003, respectively). Tumor size (p = 0.02) and nodal status (p = 0.05) were also associated with higher values of MIB-1. After adjusting for age, clinical stage, nodal status, and tumor size in a multivariate analysis, MIB-1 retained its prognostic significance (p < 0.0001) when considered as either a continuous or categorical variable. There were no significant associations between MIB-1 determined proliferation index and age (p = 0.54), histologic grade (p = 0.69), nuclear grade (p = 0.06) or the presence of vascular invasion (p =.66). There is a strong statistical relationship between cell proliferative activity, as determined by MIB-1 expression, and survival in early stage breast cancer.  相似文献   
62.
Human Fallopian tubal epithelial cells in culture lose morphological features associated with the epithelium in situ and the extent to which they retain their in-vivo phenotype or function is unknown. In order to address this question, immunocytochemical markers were identified which distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+) epithelial cells in tissue sections of Fallopian tube. These markers were used to analyse the phenotype of tubal cells in vitro. Primary cultures of human tubal epithelial cells were seeded onto glass and grown to confluence before addition of oestradiol-17beta. In the absence of hormone, tubal epithelial cells expressed cytokeratins and nuclear receptors for oestrogen and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell phenotype. Following the addition of oestradiol-17beta, a proportion of cells became positive for LhS28. The induction of a ciliated epithelial cell phenotype was confirmed by scanning electron microscopy, where on permeable collagen membranes, approximately one-third of tubal epithelial cells became ciliated in the presence of oestradiol-17beta. We suggest that in vitro, tubal epithelial cells adopt an immature secretory-like phenotype and that oestrogen can induce differentiation to a ciliated epithelial cell phenotype.   相似文献   
63.

Background  

Ser-249 TP53 mutation (249Ser) is a molecular evidence for aflatoxin-related carcinogenesis in Hepatocellular Carcinoma (HCC) and it is frequent in some African and Asian regions, but it is unusual in Western countries. HBV has been claimed to add a synergic effect on genesis of this particular mutation with aflatoxin. The aim of this study was to investigate the frequency of 249Ser mutation in HCC from patients in Brazil.  相似文献   
64.
The purpose of this article is to outline the criticality of water supply in sustained operations of healthcare facilities, particularly during community emergencies, and to advocate for enhanced cross‐sector support from the water utilities in meeting this need. Information and ideas presented here were developed in the course of a regional project sponsored by the Metropolitan Washington Council of Governments (MWCOG) for development of emergency water supply operations plans for critical water uses in the Washington, DC, area.  相似文献   
65.

The sexual practices, partner communication patterns, and prevalence of chlamydial infection were determined in a sample of college women. Specific inclusion criteria were used to screen 146 participants. The presence of a mucopurulent cervical discharge was the only criterion significantly associated with infection. Only 12% of the sample used condoms alone or in combination with another birth control method, and only 31% of the women discussed with their partner their own or their partner's sexual history. Thirty‐eight percent of the sample reported a history of one to four episodes of a sexually transmitted disease, and 21% of the women stated they had had two or more sexual partners within the past 6 months. Health providers, counselors, and women themselves must address this health issue with more assertive behavior and communication skills.  相似文献   
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