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51.
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins.  相似文献   
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子宫肌瘤与性激素及细胞凋亡的关系   总被引:2,自引:0,他引:2  
周梅  付生军 《医学争鸣》2005,26(5):446-446
1对象和方法 1.1对象随机抽取2001-10/2002-09我科住院行子宫全切术的34例子宫肌瘤患者,其中卵泡期18例,黄体期16例,年龄35~45岁. 术后均经病理证实,在手术前3 mo均未接受过激素治疗,肌瘤大小为3~8 cm3. 自肌瘤瘤体及瘤旁肌层组织各取材1份作配对比较. 瘤体为实验组,肌层为对照组. 鼠抗人ER, PR, PRL-R, Bcl-2 mAb及链霉菌抗生物素蛋白-过氧化物酶(SP)免疫组化试剂盒,均购自福州迈新生物技术开发公司.  相似文献   
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Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
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In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed.  相似文献   
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Gallium-67 lung uptake: conjugate-view technique   总被引:1,自引:0,他引:1  
A conjugate-view technique is derived for calculation of absolute gallium-67 (Ga-67) uptake from scintillation-camera images. The technique combines counts of posterior and anterior images of the lung with an attenuation correction obtained from cobalt-57 (Co-57) transmission imaging. The formulation is such that the effects of Compton scatter build-up are accounted for. Studies utilizing a canine model indicated that, normally, more activity is located in the chest wall than in the lungs. The quantitative technique must therefore accurately account for a variety of Ga-67 distributions, including that in the chest wall. Calculations were performed using a three-component model comparing results obtained with the conjugate-view approach to the actual uptake. These calculations suggest that an assumption of uniform activity distribution allows an accuracy of approximately +/- 10% over a broad range of body-part thicknesses and uptake by the lungs. It was concluded that the conjugate-view technique is necessarily approximate but can provide clinically useful results.  相似文献   
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