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991.
992.
Fiberoptic ductoscopy for patients with nipple discharge 总被引:40,自引:0,他引:40
BACKGROUND: Breast carcinoma and precancer are thought to start in the lining of the milk duct or lobule, yet until recently, we have not had direct access to this area other than by blindly removing tissue by core biopsy or fine-needle aspiration. Fiberoptic ductoscopy (FDS) is an emerging technique allowing direct visual access to the ductal system of the breast through nipple orifice exploration. METHODS: We applied ductoscopy to 259 women who had nipple discharge, and we analyzed the visual findings, the cytological washings, and the subsequent histopathology. RESULTS: In 92 (36%) of these women, fiberoptic ductoscopy was successful in detecting an intraductal papillary lesion. Of these observed lesions, 68 (74%) were single papilloma, 21 (23%) were multiple discrete papillomas, and 3 (3%) were diffuse intraductal thickening which corresponded to diffuse papillomatosis on histopathological analysis. The overall positive predictive value of FDS screening was 83%. Of the lesions observed, 29.8% were located in the main (segmental) duct, 43.9% lesions in the first branch, 17.5% lesions in the second branch, 7.9% in the third branch, and 0.9% in the fourth branch. These lesions had an overall average distance of 2.7 cm from the nipple orifice. Ductal washings performed at the time of ductoscopy were effective at obtaining representative exfoliated ductal cells which could be evaluated for the presence of clumps (> 50 cells), clumps with atypia or single ductal cells. The presence of clumps with positive FDS increased the positive predictive value to 86%. CONCLUSIONS: Fiberoptic ductoscopy currently offers a safe alternative to ductography in guiding subsequent breast surgery in the treatment of nipple discharge. 相似文献
993.
Celecoxib prevents tumor growth in vivo without toxicity to normal gut: lack of correlation between in vitro and in vivo models 总被引:15,自引:0,他引:15
Nonsteroidal anti-inflammatory drugs have potential for use in the prevention and/or treatment of colorectal cancer. We have studied the cytotoxic effect of a specific COX-2 inhibitor, celecoxib, against LLC, HCA-7, and HCT-15 cells grown in cell culture and have compared these results with its effect on HCA-7 cells grown as xenografts in nude mice. "High-dose" celecoxib (>20 microM) reduced the viability of all three cell lines in vitro as measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Flow cytometric analysis demonstrated that this loss of viability was attributable to the induction of apoptosis. Significantly, concentrations of the drug <10 microM had no effect on cell viability in vitro. The cytotoxic effects of high-dose celecoxib were independent of COX-2 inhibition because similar effects were observed in cox-2 (+/+), cox-2 (+/-) and cox-2 (-/-) fibroblasts. A plasma concentration of 2.3+/-0.7 microM was achieved when celecoxib (1250 mg/kg of chow) was fed to animals ad libitum. Despite a lack of toxicity at 2-3 microM celecoxib in vitro, there was attenuation of HCA-7 xenograft growth in vivo. Celecoxib had no effect on apoptosis, cell division, or the epithelial architecture of the normal gut in treated mice. These results support the need for additional clinical evaluation of celecoxib for treatment and/or prevention of colorectal cancer in humans. 相似文献
994.
Childhood T-cell acute lymphoblastic leukemia (T-ALL) is one of the most common childhood cancers. Recently, we observed that pre-conditioning sub-lethally irradiated immunodeficient mice with human cord blood mononuclear cells facilitates in these mice high level engraftment of primary T-ALL cells obtained from patients. Here we report that human cord blood cells secrete a factor(s) which markedly enhances in vitro both colony number and burst size of the T-ALL clonogenic progenitors from patients. The enhancing activity does not correspond to IL-2, IL-15, nor to several other cytokines implicated in T cell proliferation/activation. Thus, it is possible cord blood may secrete an as yet unidentified factor(s) acting on leukemia clonogenic progenitors of T-ALL. Collectively, these studies should prove invaluable in addressing the growth properties of primary T-ALL cells from patients. 相似文献
995.
Identification of the subcellular localization of daunorubicin in multidrug-resistant K562 cell line 总被引:5,自引:0,他引:5
We examined the subcellular distribution of daunorubicin (DNR) in resistant K562 cell line which overexpress the P-glycoprotein by confocal laser scanning microscopy. Three fluorescent probes - Rhodamine123, neutral red, NBD-ceramide, which stain the mitochondria, lysosomes, Golgi apparatus respectively, were used to identify the nature of the subcellular compartment sequestering daunorubicin. In sensitive k562 cell line, nuclear and cytoplasmic DNR fluorescence was intense and diffuse. In contrast, resistant K562 cell line showed a different DNR distribution. A bright fluorescence signal was located in the perinuclear region and peripheral plasma, the nucleus and other cytoplasmic region appear as empty, as suggested by the distribution of fluorescent probe Rhodamine123 specifically for mitochondria. Verapamil, an effective resistance modulator in P-glycoprotein MDR cells, restored the DNR distribution closer to that in the parent cells. Golgic inhibitor brefeldin A and lysosomotropic agent chloroquine had little effect on drug sequestration. Our studies demonstrate that daunorubicin may be sequestered in mitochondrial compartment in the resistant cells and P-glycoprotein plays an important role on mediating DNR transport. 相似文献
996.
NF-kappa B is required for H-ras oncogene induced abnormal cell proliferation and tumorigenesis 总被引:8,自引:0,他引:8
Jo H Zhang R Zhang H McKinsey TA Shao J Beauchamp RD Ballard DW Liang P 《Oncogene》2000,19(7):841-849
997.
健康青年男女脊柱区红外热像图的定位、定量研究 总被引:4,自引:2,他引:2
目的 :通过对健康青年男女脊柱区红外热像图的定位、定量研究 ,为医用红外热像技术的应用提供局部的相对标准参数。方法 :采用国产DW— 910 0医用红外热像仪 ,摄取正后位热像图 ,测量脊柱区不同节段的最高温度、最低温度和平均温度。结果 :(1)健康男女青年脊柱区红外热像图的平均温度分别为 (3 0 0 1±1 0 5 )℃和 (2 9 5 4± 1 19)℃。 (2 )健康男性青年脊柱区各节段红外热像图的平均温度均高于女性。结论 :健康青年男女脊柱区红外热像图的定位、定量研究 ,为正确分析人体脊柱区红外热像图提供了相对标准参数 ,具有重要的应用参考价值 相似文献
998.
Inhibitors of 5α-reductase activity cause less involution of the rat ventral prostate (VP) than does castration. Studies were conducted in adult Sprague Dawley rats to evaluate the effects of a potent 5α-reductase inhibitor, 4-MAPC, and the antiandrogen, cyproterone acetate (CA), on DNA synthesis and apoptosis. In experiment 1, VP weight fell 33%, 53%, and 83%, and DNA per ventral prostate was reduced 24%, 46%, and 71%, by 4-MAPC, CA, and castration, respectively. In experiment 2, adult rats were castrated, and the VP involuted for 7 days prior to 3 daily injections of testosterone propionate (TP; 1 mg/kg/d) ± 10 mg/kg/d of 4-MAPC or CA. 3H-thymidine incorporation into VP DNA was increased in castrated animals treated with TP, and 4-MAPC and CA reduced uptake. In experiment 3, animals were treated for 14 days with the same protocol as that used in experiment 2. VP weight was increased in all animals treated with TP when compared with castration, and was reduced by both 4-MAPC and CA. DNA in rats treated with TP was similar to that in intact animals. DNA was not reduced by 4-MAPC, but was reduced by CA. The mRNA for TRPM-2, a marker of apoptosis, was increased only in untreated castrated rats. It appears that CA has a greater inhibitory effect than 4-MAPC on DNA synthesis. A major reason why castration reduces DNA more than either 4-MAPC or CA is that neither of these agents was able to increase programmed cell death to the degree seen with castration. © 1994 Wiley-Liss, Inc. 相似文献
999.
宁国贝母生物碱的分离和结构鉴定 总被引:2,自引:0,他引:2
从贝母新种——宁国贝母(Fritillaria ningguoensis S. C. Chen et S. F. Yin)鳞茎中分离出五个生物碱,其中碱V是一种新的生物碱,命名为宁贝新(ningpeisine),根据理化常数和光谱解析以及衍生物制备,测定其结构为N-methyl-3β-hydroxy-5α-veratranine-6-one。其余四种生物碱鉴定为浙贝甲素(peimine,verticine,Ⅰ),浙贝乙素(peiminine,verticinone,Ⅱ),异浙贝甲素(isoverticine,Ⅲ)和贝母辛(peimisine,Ⅳ)。 相似文献
1000.
为进一步保证巨乳缩小术后乳头乳晕的血供和感觉,简化手术操作。设计乳房下锥形真皮瓣,同时把皮肤磨削术应用于巨乳缩小术。自1994年1月至1997年6月为8例(16侧)巨乳患者实施手术。全部患者术后乳头乳晕无并发症。并能大大缩短手术时间。认为皮肤磨削术乳房下锥形真皮瓣不仅可以确保乳头、乳晕的血供和感觉,且可以大大缩短手术时间,减少术后并发症 相似文献