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991.
BACKGROUND: The role of anthracyclines has been extensively studied in adjuvant chemotherapy, but much less in the primary chemotherapy of early breast carcinoma. This study, comparing CMF (cyclophosphamide, methotrexate, 5-fluorouracil) with the rotational anthracycline-containing regimen CMFEV (CMF plus epirubicin and vincristine) administered as primary chemotherapy, demonstrated a significant increase in clinical complete response in premenopausal women. We report the long-term results. PATIENTS AND METHODS: Two hundred and eleven patients with stage I or II palpable breast carcinoma and a tumour diameter of >2.5 cm were randomised to receive CMF or CMFEV for four cycles before surgery. After surgery, the patients in both arms received adjuvant CMF for three cycles. RESULTS: In the study population as a whole, there was a non-significant 20% reduction in mortality and relapse rates in the CMFEV arm. However, the effect of the experimental regimen was only found in premenopausal patients, especially in terms of relapse-free survival (P=0.07) and locoregional relapse-free survival (P=0.0009), thus mirroring the effect on response rates. After 10 years, the proportions of premenopausal patients free from locoregional relapse as a first event in the CMF and CMFEV groups were 68% and 97%, respectively. No relevant differences were found in postmenopausal patients. CONCLUSION: The overall results of this study showed that the greater activity of the experimental anthracycline-containing combination over CMF as primary chemotherapy in premenopausal patients translated into long-term effects in the same subgroup.  相似文献   
992.
993.
高强度聚焦超声治疗肝癌的初步临床研究   总被引:2,自引:0,他引:2  
目的:探讨应用高强度聚焦超声(high intensity focused ultrasound,HIFU)治疗肝癌的临床疗效.方法:回顾性分析40例肝癌患者应用JC型HIFU肿瘤治疗系统进行治疗的病例资料,观察HIFU治疗前后临床症状、肝功能、AFP及影像学(CT或MRI)的变化.结果:40例患者经HIFU治疗后,临床症状缓解率为82.4%(28/34),肝功能好转者占88.9%(32/36),AFP降低超过原数值50%者占80%(16/20),CT或MRI显示靶区肿瘤已凝固性坏死,肿瘤血供减少或消失.结论:应用HIFU治疗肝癌是一种安全、有效和非侵入性的治疗肝癌的新方法.  相似文献   
994.
Differentiation of abdominal masses detected on prenatal ultrasound is difficult and requires careful characterization of the mass and precise localization. Differentiation is required in order to distinguish benign from potentially malignant conditions. We describe a case of fetus‐in‐fetu with pre and postnatal imaging.  相似文献   
995.
An important aspect of the chemopreventive activity of isothiocyanates (ITC) is their ability to induce cell growth inhibition and apoptosis. In this study, the effect of two sulforaphane analogues, 2‐oxoheksyl isothiocyanate and alyssin, on lymphoblastoid cells, derived from people carrying four different germ‐line mutations in BRCA1 gene, was tested and compared to the effect on wild type cells. The mutations studied were: C61G; 3819del5; 4153delA, and 5382INSC. Changes in cell viability and density after 2‐oxoheksyl isothiocyanate and alyssin treatment were evaluated, as well as cell cycle progression, mitochondrial membrane potential changes, and phosphatidylserine externalization. Both isothiocyanates were shown to reduce cell viability and density in all cell lines tested, as well as the change in cell cycle phase's distribution. The response of cells to two ITC tested was various, as well as mutation type‐modulated. We found that change of cellular maintenance by chemopreventive agents can be modulated by single allele BRCA1 mutation. Drug Dev. Res. 65:84–92, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
996.
Directed ortho‐metalation (DoM) strategy has been applied for the development of a short procedure for the regiospecific synthesis of [phenyl2H4]‐2‐bromo‐benzylamine 6 starting from commercially available [phenyl2H5]‐benzoyl chloride 1 . A strong isotope effect was observed during the ortho‐substitution. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
997.
Recent advances in the chemistry of radiolabeling with 99mTc such as use of the 99mTc tricarbonyl and 99mTc–HYNIC cores have revived interest in 99mTc‐labeling of small biomolecules and further investigation as potential radiopharmaceuticals. Isoniazid, a drug commonly used for treatment of tuberculosis, has been chosen for the present study. Three distinct strategies were utilized to radiolabel isoniazid with 99mTc. In the direct labeling protocol, the hydrazino amide functional group of isoniazid was used for 99mTc‐labeling in the HYNIC sense using tricine and EDDA as co‐ligands. The other strategies of 99mTc‐labeling involved the derivatization of isoniazid to its N, N‐diacetic acid derivative, which in turn was either used as a tridentate ligand for labeling with the [99mTc(CO)3(H2O)3]+ synthon or directly labeled by the conventional route wherein 99mTc is in the +3 oxidation state. The complexes prepared in >95% yields were characterized by paper chromatography, thin layer chromatography and HPLC. Comparison of the three approaches showed that maximum specific activity and stability was obtained in the 99mTc–isoniazid derivative synthesized via the tricarbonyl method. However, in vitro cell‐binding studies indicated that none of the 99mTc–isoniazid complexes prepared had any appreciable uptake in Mycobacterium tuberculosis. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
998.
A convenient synthesis of chloramphenicol labelled with carbon‐14 in the dichloroacetyl group at the 1 position is described. It was prepared as part of a 4‐step sequence from [1 ‐ 14C] glycine and the product was purified by preparative HPLC. A radiochemical yield of 47% was obtained based on [1 ‐ 14C] glycine and the product had a specific activity of 0.47 mCi/mmol. The procedure can be employed for the synthesis of high specific activity [14C] chloramphenicol, labelled at 1, 2 or both the positions of dichloroacetyl group. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
999.
The feasibility of synthesizing compounds containing the P–18F bond has been demonstrated by labelling the pesticide, cholinesterase inhibitor Dimefox (N,N,NN′‐tetramethylphosphorodiamidic fluoride) with F‐18. Radiolabelling was achieved in high radiochemical yield (96%) by nucleophilic substitution of the chloro group attached to phosphorus, in the oxidation state P(V), by 18F? (activated with tetrabutylammonium carbonate in acetonitrile). Given the large number of important biological molecules possessing phosphorus such as oligonucleotides, phospholipids as well as phosphorylated proteins, sugars and steroids, this new labelling chemistry may provide an additional route to radiolabelling these biologically important compounds for use in PET. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
1000.
A fluorine‐18 labeled analog of the widely used chemotherapeutic agent cyclophosphamide was synthesized as a tracer for prognostic imaging with positron emission tomography. 2‐[(2‐Chloro‐2′‐[18F]fluoroethyl)amino]‐2H‐1,3,2‐oxazaphosphorinane‐2‐oxide (18F‐fluorocyclophosphamide), was prepared by direct halogen exchange reaction from the parent cyclophosphamide. In small‐scale syntheses, radiochemical yields of up to 4.9% and specific activities of 960 Ci/mmol were achieved in a total synthesis time of 60–75 min. The [18F]‐labeled cyclophosphamide analog with radioactive purity >99% and chemical purity >96% was suitable for in vivo (microPET imaging) and ex vivo studies of a murine model of human breast tumors. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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