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11.
The antineoplastic properties of suramin, a polyanionic agent with demonstrated antigrowth factor activity, are under evaluation in vitro, in vivo, and in clinical trials. Suramin has been shown to have antitumor activity in patients with advanced, hormone refractory prostate cancer. During these trials, significant resolution of osseous pain was observed in nearly three quarters of the patients treated with suramin. To evaluate the effect of suramin on bone cells, we studied the effect of suramin on bone resorption in a neonatal mouse calvarial assay. Suramin inhibited bone-resorbing activity in a dose-related fashion and had an additive effect with calcitonin. Calvaria pretreated with suramin had less bone-resorbing activity, fewer attached osteoblasts, and less medium alkaline phosphatase activity than control calvaria. Suramin also inhibited osteoclastic release of tritiated proline from labeled bone in a dose-dependent fashion. The effect of metastatic prostate carcinoma on bone is incompletely understood, but may be moderated by tumor-produced factors and/or cytokines. The effects of several such agents, therefore, were examined in combination with suramin. Bone resorption induced by PTH, epidermal growth factor, tumor necrosis factor, and a tumor-produced factor, PTH related-protein, was blocked by suramin. The ability of suramin to inhibit the bone-resorbing effects of several cytokines suggests that its mechanism may involve direct action on bone metabolism. Autoradiography performed on calvaria treated with labeled suramin demonstrated heavy deposition of suramin on the outer surface of the matrix, adjacent to osteoblasts and osteoclasts lining the outer table, suggesting that bone cells may be subject to high local concentrations of the drug, in keeping with this hypothesis.  相似文献   
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353 patients with stages pTis, pT1-2, pN0-1, cM0 breast cancer have been treated consecutively by breast conserving therapy in a prospective, nonrandomized study at the University Hospital Basel and the Women's Clinic Rheinfelden/Baden/Germany. The median age was 47 years, the median follow-up time 67 months, and 4% only of this collective were lost to follow-up after a median time of 42 months. In 79% of the cases the tumor was excised totally, while in 19% the resection margins were positive and in 2% only the margins were not available for histological judgement. The rate of local failure reached 8% with a median time interval of 53 months. 116 patients showed postactinic induration in the primary tumor region. 73 of these were given additional diagnostic examination: The postactinic induration was judget clinically suspicious in 51 cases and clinically nonsuspicious of local failure in 22 cases. All 73 patients received additional examination by mammography and biopsy. By comparison with the histological results the clinical results were correct in 59% and false in 41%, while the mammographic results were correct in 82% and false in 18% of the cases.  相似文献   
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The catechol-O-methyltransferase (COMT) Val158Met polymorphism modulates executive functions and working memory and recent neuroimaging studies implicate an association with emotional processing. We examined the relationship between the COMT Val158Met polymorphism and facial emotion recognition and differentiation in 100 healthy individuals. Compared to Met homozygosity, Val homozygosity was associated with better and faster recognition of negative facial expressions such as anger and sad. Our study provides evidence for a possible influence of the COMT polymorphism on emotion recognition abilities in healthy subjects. Additional research is needed to further define the neurocognitive phenotypes associated with COMT polymorphisms.  相似文献   
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New reproductive technologies such as in vitro fertilization (IVF) offer much hope to infertile couples, yet the odds for success are not high. In this study we examine the experiences of a cohort of women undergoing IVF or a related technology at three points in time: before technological intervention, approximately one month after the first failed cycle, and six months later. We consider the women's expectations and experiences and discuss implications of the findings for social work practice.  相似文献   
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Summary The combination of tumor necrosis factor (TNF) and etoposide (ETP) was evaluated for potential cytotoxic efficacy against a human renal cell carcinoma xenograft using an in vivo assay employing an athymic mouse host with tumor implanted a the subrenal capsule site. Both antitumor efficacy (relative survival or RTS) and toxicity (weight loss) of TNF and ETP alone and in combination were evaluated. While TNF and ETP alone were mildly inhibitory (RTS 90% and 71%, respectively), the combination caused marked tumor inhibition (45% of controls). Host toxicity encountered with the combination did not exceed the toxicity associated with ETP alone, suggesting that the therapeutic index may have been augmented. It is concluded that enhanced antitumor activity without substantial augmentation of toxicity is observed with this combination, providing a rationale for further evaluation of tumor necrosis factor-based regimens for the treatment of advanced renal carcinoma.Supported by a Merit Review grant, VA Medical Research Service, Durham, NC 27710, USA  相似文献   
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Radical prostatectomy: anatomical predictors of success or failure   总被引:1,自引:0,他引:1  
A total of 143 patients underwent radical prostatectomy. Surgical specimens were evaluated with respect to local extent of disease, Gleason grade of the primary and relative nuclear roundness of the surgical specimen. The probability of disease control in the total population was 88 per cent at 5 years. Only 8 per cent of the patients who had disease confined to the specimen failed compared to 14 per cent of those who demonstrated extension outside of the surgical margins. The incidence of failure increased as a function of seminal vesicle involvement. Seminal vesicle involvement was greatest among patients with a Gleason grade greater than 7. Postoperative radiation did not offer any apparent advantage in patients with positive margins.  相似文献   
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