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991.

Introduction

Phytoestrogens are a group of compounds found in plants that structurally resemble the hormone oestradiol, and thus have the potential to act as oestrogen agonists or antagonists. Their potential effects may alter the risk of breast cancer, but only a limited range of phytoestrogens has been examined in prospective cohort studies.

Methods

Serum and urine samples from 237 incident breast cancer cases and 952 control individuals (aged 45 to 75 years) in the European Prospective into Cancer-Norfolk cohort were analysed for seven phytoestrogens (daidzein, enterodiol, enterolactone, genistein, glycitein, o-desmethylangolensin, and equol) using liquid chromatography/mass spectrometry. Data on participants' diet, demographics, anthropometrics, and medical history were collected upon recruitment. All models were adjusted for weight, fat and energy intake, family history of breast cancer, social class, analytical batch, and factors related to oestrogen exposure.

Results

Urinary or serum phytoestrogens were not associated with protection from breast cancer in the European Prospective into Cancer-Norfolk cohort. Breast cancer risk was marginally increased with higher levels of total urinary isoflavones (odds ratio = 1.08 (95% confidence interval = 1.00 to 1.16), P = 0.055); among those with oestrogen receptor-positive tumours, the risk of breast cancer was increased with higher levels of urinary equol (odds ratio = 1.07 (95% confidence interval = 1.01 to 1.12), P = 0.013).

Conclusion

There was limited evidence of an association between phytoestrogen biomarkers and breast cancer risk in the present study. There was no indication of decreased likelihood of breast cancer with higher levels of phytoestrogen biomarkers, but the observation that some phytoestrogen biomarkers may be associated with greater risk of breast cancer warrants further study with greater statistical power.  相似文献   
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卵巢交界性浆液、粘液性肿瘤病理诊断新概念   总被引:1,自引:0,他引:1  
范娣  郭东辉 《肿瘤学杂志》2001,7(4):196-199
本文总结近年有关卵巢交界性浆液、小数点 液性肿瘤文献论述病理诊断的新概念。分别为:(1)卵巢交界性肿瘤基本诊断标准;(2)卵巢交界性浆液性肿瘤概括Piura(1992),Russel(1994)、Silva(1996),Eichhorn(1999),Scully(1999)病理诊断标准;(3)卵巢交界性粘液肿瘤概括Piura(1992),Kuman(1996),Riopel(1999),Scully(1999)病理诊断标准。(4)腹膜假粘液瘤;(5)上皮内癌;(6)微浸润;(7)种植;(8)淋巴结转移;(9)多中心性;(10)命名;(11)预后。  相似文献   
996.
目的:探讨从事混合苯作业人员血红蛋白(Hb)含量变化。方法:分析男女从业人员的Hb含量与接毒浓度、接毒工龄、接毒年龄的关系。结果:作业人员Hb含量较正常的下限低(P<0.001),男性从业人员的Hb含量与接毒浓度间存在负相关(P=0.039),女性的Hb含量与接毒工龄间存在正相关。结论:从事混苯作业人员Hb含量有明显下降,改善作业环境及就业后定期体检应作为职业卫生工作的重点。  相似文献   
997.
KARs, new semisynthetic antitumor bis-indole derivatives, were found to be inhibitors of tubulin polymerization with lower toxicity than vinblastine or vincristine, used in chemotherapy. Here, we compare the effect of KARs with those of vinblastine and vincristine on cell viability, cell proliferation, and cell cycle in neuroblastoma cell line (SH-SY5Y). At concentrations of the different compounds equivalent in causing 50% of inhibition of cell growth, KARs induced a complete arrest in the G2/M phase, whereas vinblastine and vincristine induced a partial arrest in both G0/G1 and G2/M. Moreover, a combination of KAR-2 and W13 (an anticalmodulin drug) qualitatively caused a similar arrest in both G0/G1 and G2/M than vinblastine. Levels of cyclin A and B1 were higher in KARs-treated cells than in vinblastine- or vincristine-treated cells. Cdc2 activity was much higher in KAR-2 than in vinblastine-treated cells, indicating a stronger mitotic arrest. The effect of KAR2 and vinblastine on microtubules network was analyzed by immunostaining with anti-tubulin antibody. Results indicated that KAR-2-induces the formation of aberrant mitotic spindles, with not apparent effect on interphase microtubules, whereas vinblastine partially destroyed interphase microtubules coexisting with normal and aberrant mitotic spindles.  相似文献   
998.
PURPOSE: To report on the treatment of patients with newly diagnosed neuroblastoma presenting with spinal cord compression (SCC). PATIENTS AND METHODS: Of 1,462 children with neuroblastoma registered between 1979 and 1998, 76 (5.2%) presented with signs/symptoms of SCC, including motor deficit in 75 patients (mild in 43, moderate in 22, severe [ie, paraplegia] in 10), pain in 47, sphincteric deficit in 30, and sensory loss in 11. Treatment of SCC consisted of radiotherapy in 11 patients, laminectomy in 32, and chemotherapy in 33. Laminectomy was more frequently performed in cases with favorable disease stages and in those with severe motor deficit, whereas chemotherapy was preferred in patients with advanced disease. RESULTS: Thirty-three patients achieved full neurologic recovery, 14 improved, 22 remained stable, and eight worsened, including three who become paraplegic. None of the 10 patients with grade 3 motor deficit, eight of whom were treated by laminectomy, recovered or improved. In the other 66 patients, the neurologic response to treatment was comparable for the three therapeutic modalities. All 11 patients treated by radiotherapy and 26 of 32 patients treated by laminectomy, but only two of 33 treated by chemotherapy, received additional therapy for SCC. Fifty-four of 76 patients are alive at time of the analysis, with follow-up of 4 to 209 months (median, 139 months). Twenty-six (44%) of 54 survivors have late sequelae, mainly scoliosis and sphincteric deficit. CONCLUSION: Radiotherapy, laminectomy, and chemotherapy showed comparable ability to relieve or improve SCC. However, patients treated with chemotherapy usually did not require additional therapy, whereas patients treated either with radiotherapy or laminectomy commonly did. No patient presenting with (or developing) severe motor deficit recovered or improved. Sequelae were documented in 44% of surviving patients.  相似文献   
999.
We selected 14 patients with advanced idiopathic Parkinson's disease (PD) and examined the clinical effects of STN DBS versus GPi DBS. Nine patients underwent bilateral STN DBS and five underwent bilateral GPi patients. All patients were followed for at least 12 months. The evaluation was performed on and off drug before surgery; on-drug/on-DBS and off-drug/on-DBS at 1, 2, 6 and 12 months after stereotactic surgery. At 1 and 3 months after surgery in off-drug/on-DBS condition, both groups showed an improvement in motor score (UPDRS II). Nevertheless, the results changed after long-term stimulation in the two groups. Chronic STN DBS is superior to GPi DBS in the amelioration of the clinical features and in the decrease of time spent in the off state. The efficacy in reduction of LID was comparable at 1 and 3 months after surgery, but the results were better in STN DBS after chronic stimulation. The L-dopa dose was reduced only in the STN group.  相似文献   
1000.
The new cembrane diterpenes leptodienone A (2) and leptodienone B (3) and the known compounds lopholide, lophodiol B, lophodione, and lophotoxin (1) have been isolated from the gorgonian Leptogorgia laxa collected in the Gulf of California. The structures of the new metabolites have been established by spectroscopic techniques. The in vitro cytotoxicity of the new compounds has been tested against three human tumor cell lines.  相似文献   
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