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51.
《Journal of labelled compounds & radiopharmaceuticals》2005,48(9):693-700
[(1R)‐endo]‐(+)‐3‐bromocamphor was dehalogenated with tritium gas to [3‐3H]camphor and via [3‐3H]phenylborneol converted to [3‐3H]deramciclane isolated as the fumarate salt (specific activity 51.8 GBq/mmol). This three step synthesis from [3‐3H]camphor gave an overall yield of 22%. Benzyloxy‐acetic acid methyl ester was reduced with sodium‐borotritide to 2‐benzyloxy‐ethanol‐[1‐3H], and through a four step procedure was converted to 2‐dimethylaminoethyl‐[2‐3H] chloride. The latter was condensed with the sodium derivative of 2‐phenylborneol giving rise to [2‐dimethylamino‐[2‐3H]ethoxy]deramciclane isolated as the fumarate (specific activity 8.177 GBq/mmol). This six step synthesis from [3H]NaBH4 gave an overall yield of 6%. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
52.
Andries S. Koster 《Pharmacy World & Science》1991,13(3):123-126
Quinones can be metabolized by various routes: substitution or reductive addition with nucleophilic compounds (mainly glutathione and protein thiol groups), one-electron reduction (mainly by NADPH: cytochrome P-450 reductase) and two-electron reduction (by D,T-diaphorase). During reduction semiquinone radicals and hydroquinones are formed, which can transfer electrons to molecular oxygen, resulting in the formation of reactive oxygen intermediates and back-formation of the parent quinone (redox cycling). Reaction of semiquinones and reactive oxygen intermediates with DNA and other macromolecules can lead to acute cytotoxicity and/or to mutagenicity and carcinogenicity. The enhanced DNA-alkylating properties of certain hydroquinones are exploited in the bioreductive alkylating quinones. Acute cytotoxicity of quinones appears to be related to glutathione depletion and to interaction with mitochondria and subsequent disturbance of cellular energy homoeostasis and calcium homoeostasis. These effects can to a certain extent be predicted from the electron-withdrawing and electron-donating effects of the substituents on the quinone nucleus of the molecule. Prediction of cytostatic potential remains much more complicated, because reduction of the quinones and the reactivity of the reduction products with DNA are modulated by the prevailing oxygen tension and by the prevalence of reducing enzymes in tumour cells.This article is based on a lecture given at the 16th LOF Symposium, 27 October 1989, Utrecht, the Netherlands. 相似文献
53.
Alemtuzumab (CAMPATH 1H) Induction Therapy in Cadaveric Kidney Transplantation—Efficacy and Safety at Five Years 总被引:2,自引:0,他引:2
Christopher J. E. Watson J. Andrew Bradley Peter J. Friend John Firth Craig J. Taylor John R. Bradley Kenneth G. C. Smith Sathia Thiru Neville V. Jamieson Geoff Hale Herman Waldmann Roy Calne 《American journal of transplantation》2005,5(6):1347-1353
Alemtuzumab is a powerful lymphocyte depleting antibody currently being evaluated in solid organ transplantation. This paper describes 5-year results of a single center study of alemtuzumab as induction in renal transplantation. Thirty-three renal transplant recipients received 20 mg alemtuzumab on day 0 and 1, followed by half-dose cyclosporin monotherapy (trough concentration 75-125 ng/mL) from day 3. They were compared in a retrospective contemporaneous-controlled manner with 66 kidney transplant recipients transplanted in the same period and center who received conventional immunosuppression with cyclosporin, azathioprine and prednisolone. In the alemtuzumab group 12% of recipients died compared to 17% in the control group (p = 0.48); likewise graft loss was similar in both groups (21% vs. 26%, respectively, p = 0.58). Incidence of acute rejection was also comparable at 5 years (31.5% vs. 33.6%), although the pattern of rejection was different with 14% patients in the alemtuzumab group experiencing rejection over 1 year post-transplant compared to none in the control group. There was no significant difference between groups in terms of infection or serious adverse events. While acknowledging the limitations of a relatively small single-center study, results suggest that alemtuzumab induction allowed satisfactory long-term patient and graft survival equivalent to that seen with standard triple immunosuppression, while avoiding steroid therapy. 相似文献
54.
55.
包含颈外静脉的颈阔肌肌皮瓣修复口腔癌切除后缺损 总被引:1,自引:0,他引:1
目的探讨将颈外静脉包含在颈阔肌肌皮瓣内修复口腔癌切除后缺损的手术方法。方法先形成蒂在颌缘下包含颈外静脉的颈阔肌肌皮瓣,待口腔肿瘤切除后,将肌皮瓣经口底隧道引入口腔修复缺损。结果临床应用17例,肌皮瓣均无血运障碍,100%存活,其中有2例发生口面痿,经换药后痿口完全闭合。结论将颈外静脉包含在颈阔肌肌皮瓣内有助于肌皮瓣血循环的改善和存活率的提高。 相似文献
56.
黄震华 《中国新药与临床杂志》2005,24(10):829-832
心肌钠钙交换在调节心肌细胞内外钠、钙平衡中发挥重要作用。钠钙交换分为前向型和逆向型2种。在心力衰竭、心肌缺血、心肌再灌注等病理情况下,通过钠钙交换器的离子交换可产生致心律失常性的一过性内向电子流,引起延迟后除极和非折返激动型的室性心动过速。钠钙交换器抑制药在预防这些病理情况下的心律失常具有潜在的作用。 相似文献
57.
Overactive bladder (OAB) is a prevalent and costly condition that can affect any age group. Typical symptoms include urinary urgency, frequency, incontinence and nocturia. OAB occurs as a result of abnormal contractions of the bladder detrusor muscle caused by the stimulation of certain muscarinic receptors. Therefore, antimuscarinic agents have long been considered the mainstay of pharmacologic treatment for OAB. Currently, there are five such agents approved for the management of OAB in the United States: oxybutynin, tolterodine, trospium, solifenacin and darifenacin. This article summarizes the efficacy, contraindications, precautions, dosing and common side effects of these agents. All available clinical trials on trospium, solifenacin and darifenacin were reviewed to determine its place in therapy. 相似文献
58.
Systemic anticancer therapy for hepatocellular carcinoma (HCC) is limited by intrinsic drug resistance and accompanying liver
dysfunction. However, recent advances in molecular targeted therapy (MTT) have shed light on the treatment of advanced HCC.
A recent randomized, placebo-controlled trial demonstrated that sorafenib, a multi-target tyrosine kinase inhibitor, prolonged
overall survival and time-to-progression in patients with advanced HCC. This breakthrough highlights the potential of MTT
targeting hepatocarcinogenic pathways, such as the Raf/MAPK/ERK pathway, angiogenic pathways and the EGFR signaling pathway.
This review discusses the current status and the potential of developing novel MTTs for advanced HCC. 相似文献
59.
目的探讨口腔鳞状细胞癌颈淋巴转移范围和临床病理因素间的关系。方法对26例已存在颈淋巴转移的原发口腔癌患者,进行颈淋巴转移范围和患者的临床病理资料的统计分析,寻找影响转移范围的主要因素。结果单因素分析发现,肿瘤生长方式和分化程度与转移范围相关。多因素分析显示,肿瘤生长方式(浸润型)和肿瘤转移范围相关。结论对颈淋巴已有转移的口腔癌患者,若原发灶为浸润性生长,肿瘤倾向于更大范围的转移。对已有颈淋巴转移的口腔癌患者,颈淋巴清扫术范围的制定,主要考虑肿瘤生长方式,适当考虑肿瘤发病部位、厚度、大小和细胞的分化程度,可以不考虑患者年龄和性别。 相似文献
60.
Summary The objective of this study was to evaluate the effect of two non-steroid anti-inflammatory drugs, indomethacin and metamizole, on ureteral peristalsis during acute occlusion similar to the situation in renal colic. In 12 pentobarbital anesthetized sheep, both ureters were cannulated and the frequency of ureteral contractions, urine flow, mean ureteral pressure and blood pressure were recorded during 10-min control and i.v. drug administration periods. Both indomethacin (1–2 mg/kg) and metamizole (60–120 mg/kg) showed a dose dependent reduction in peristaltic frequency without reduction of the mean pressure. In addition, the pressure amplitude of the peristaltic waves was also lowered, particularly with indomethacin. Only indomethacin reduced the urine flow. Arterial blood pressure was elevated by both drugs, particularly after the first dose of indomethacin. It can be concluded that indomethacin and metamizole reduce ureteral peristaltic frequency, probably blocking the impulse transmission at the ureteropelvic junction.For the partial fulfillment of a Master's degree in Pharmacology 相似文献