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113.
Peter C. Albertsen Laurence Klotz Bertrand Tombal James Grady Tine K. Olesen Jan Nilsson 《European urology》2014
Background
Androgen deprivation therapy (ADT) is associated with increased cardiovascular morbidity.Objective
To determine whether cardiovascular morbidity differs following initiation of gonadotropin-releasing hormone (GnRH) agonists compared with an antagonist.Design, setting, and participants
Pooled data from six phase 3 prospective randomized trials that recruited 2328 men between 2005 and 2012 to compare the efficacy of GnRH agonists against an antagonist. Men recruited had pathologically confirmed prostate cancer, an Eastern Cooperative Oncology Group score <2, a minimum life expectancy of 12 mo, and were naïve to ADT. Men were excluded if they had a prolonged baseline QT/corrected QT interval, other risk factors for heart failure, hypokalemia or a family history of long QT syndrome, or had another cancer diagnosed within 5 yr.Intervention
Men were randomized to receive a GnRH agonist or an antagonist for either 3–7 mo (n = 642) or 12 mo (n = 1686). Treatment groups were balanced for common baseline characteristics.Outcome measurements and statistical analysis
Event analysis was based on death from any cause or cardiac events. Data documenting adverse experiences were classified based on the Medical Dictionary for Regulatory Activities. The following conditions defined a cardiac event: arterial embolic or thrombotic events, hemorrhagic or ischemic cerebrovascular conditions, myocardial infarction, and other ischemic heart disease. Kaplan-Meier curves and log-rank tests were used to compare time to a cardiovascular event or death.Results and limitations
Among men with preexisting cardiovascular disease, the risk of cardiac events within 1 yr of initiating therapy was significantly lower among men treated with a GnRH antagonist compared with GnRH agonists (hazard ratio: 0.44; 95% confidence interval, 0.26–0.74; p = 0.002). Since our analysis is post hoc, our findings should only be interpreted as hypothesis generating.Conclusions
GnRH antagonists appear to halve the number of cardiac events experienced by men with preexisting cardiovascular disease during the first year of ADT when compared to GnRH agonists. 相似文献114.
New anastomosis technique for (laparoscopic) instrumental small-diameter anastomosis 总被引:2,自引:1,他引:2
O. Schöb R. Schmid R. Schlumpf H. P. Klotz M. Spiess F. Largiadèr 《Surgical endoscopy》1995,9(4):444-449
This study presents a new technique for visceral anastomosis. The principle consists of connecting the two parts to be anastomosed around a reabsorbable stent which is transluminally introduced into a small-diameter viscus, where it is fixed. Advancing a larger tube along the axis of the machine, the larger, perforated viscus is inverted and pulled over the stent, and finally a rubber band pops off the machine endoluminally in order to fix the intestinal walls in seroserosal contact onto the stent. To evaluate this micro anastomosis, a biliary bypass (choledochojejunostomy and roux-en-y-loop) was performed in ten pigs. Nine of ten animals showed biliary bypass with good runoff in contrast radiography and completely reabsorbed stent after a 3-month follow-up. Weight gain, bilirubin, and alkaline phosphatase were normal. This technology demonstrates a safe and quick way to perform instrumental micro anastomosis without remnant foreign material.Presented as a poster at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, TN, USA, 18–19 April 1994 相似文献
115.
目的 探讨马钱子碱抗肝细胞癌的作用及其机制.方法 体外培养人肝癌SMMC-7721细胞,加入不同浓度的马钱子碱(2.5~400μg/ml),细胞培养72 h,MTT法测定细胞生长抑制率.Western blotting和荧光定量RT-PCR技术分别测定培养24、48、72 h肝癌细胞PCNA、Cyclin D1、FAS基因mRNA和蛋白表达.结果 随着马钱子碱用量逐渐增加,对人肝癌细胞SMMC-7721生长抑制作用增强,马钱子碱用量为320 μg/ml时对肝癌细胞生长抑制率接近100%.马钱子碱作用肝癌细胞24 h与作用48 h相比,Fas蛋白和mRNA表达差异无统计学意义(分别F=2.547,1.582,均P>0.05),作用72 h时差异有统计学意义(分别F=1.036,1.137,均P<0.05);PCNA和Cyclin D1的mRNA和蛋白表达各时间点差异无统计学意义(PCNA分别F=3.612,2.174,3.029;Cyclin D1分别F=2.361,2.915,1.976,均P>0.05).结论 马钱子碱抑制肝癌细胞生长,可能通过肝癌细胞FAS基因和蛋白表达增加,诱导肝癌细胞凋亡发挥抑制作用,而与PCNA和Cyclin D1作用无关.Abstract: Objective To study the effect of brucine on the growth of a hepatocellular carcinoma cell line in vitro. Methods Brucine was added into a liver cancer cell line of SMMC-7721 in vitro, at drug concentration of brucine from 2. 5 μg/ml to 400 μg/ml. The inhibition rate of cell growth was measured by MTT technique after the cells were cultured for 72 hours. The protein and mRNA expression of PCNA,cyclin D1 and FAS were respectively assayed with Western blotting and fluorescent quantitation RT-PCR techniques at 24, 48, 72 h. Results The inhibition rate of liver cancer cell was near 100% when the brucine concentration was at 320 μg/ml. The protein and mRNA expression of FAS were of no significant difference at 24 h vs 48 h ( seperately F = 2. 547,1. 582, all P > 0. 05 ), and significant difference existed at 24 h vs 72 h( seperately F = 1. 036, 1. 137, all P < 0. 05 ). The protein and mRNA expression of PCNA,Cyclin D1 were of no significant difference between various time period( seperately PCNA F = 3.612,2. 174,3.029;Cyclin D1 F=2.361,2.915,1.976,all P>0.05). Conclusions Brucine inhibits the growth of liver cancer cells, by inducing increased apoptosis of the cells probably through FAS overexpression. 相似文献
116.
目的:探讨柠檬酸对术后首次行131I治疗(简称清甲治疗)的分化型甲状腺癌(DTC)患者唾液腺功能的影响,阐明柠檬酸对131I治疗的甲状腺癌患者唾液腺功能的保护作用。方法:经患者知情同意,随机选择准备首次行131I治疗的68例甲状腺乳头状癌患者,随机分为对照组和柠檬酸组,每组34例。对照组患者无特殊准备,柠檬酸组患者于131I治疗前1周及治疗后3周内每天含柠檬酸1 min(0.2 g/次)后吐出。2组患者分别于131I治疗前24 h及131I治疗后3个月行2次99mTcO4-唾液腺显像检查,计算第15分钟摄取指数(15 min UI)和排泌分数(SR),评估唾液腺功能。结果:与131I治疗前比较,对照组患者131I治疗后右侧腮腺和双侧颌下腺15 min UI差异无统计学意义(P>0.05),左侧腮腺15 min UI降低(P<0.05);与131I治疗前比较,柠檬酸组患者131I治疗后双侧腮腺及双侧颌下腺15 min UI差异无统计学意义(P>0.05);与对照组比较,柠檬酸组患者131I治疗前后双侧腮腺和双侧颌下腺15 min UI差异均无统计学意义(P>0.05)。与131I治疗前比较,对照组患者双侧腮腺治疗后SR降低(P<0.05),双侧颌下腺SR差异无统计学意义(P>0.05),柠檬酸组患者双侧腮腺和双侧颌下腺治疗后SR差异无统计学意义(P>0.05);与对照组131I治疗后比较,柠檬酸组患者双侧腮腺SR升高(P<0.05),双侧颌下腺SR差异无统计学意义(P>0.05)。结论:DTC患者术后首次131I治疗后唾液腺排泌功能可能受损,短期口含柠檬酸对唾液腺具有保护作用,可以减轻唾液腺的放射性损伤。 相似文献
117.
目的 研究长爪沙鼠发情周期,揭示发情规律,优化判定方法。方法 连续18 d采集50只长爪沙鼠阴道上皮脱落细胞涂片,采用角化细胞计数法研究长爪沙鼠发情周期规律。比较瑞氏染色、HE染色和直接镜检判定发情周期4个时相的优缺点。结果 长爪沙鼠的发情周期有稳定型、不稳定型、假孕三种类型。其中稳定型占68.6%,发情周期为(106.3±35.0)h,可分为4个时相。4个时相角化细胞的比例分别为发情前期(13.5±7.8)%、发情期(86.7±9.9)%、发情后期(27.9±12.8)% 和发情间期(3.3±2.8)%。结论 角化细胞计数能准确地判定长爪沙鼠的发情周期及各个时相。直接镜检法能快速反映阴道脱落细胞的形态。 相似文献
118.
G Cristalli A Eleuteri S Vittori R Volpini M J Lohse K N Klotz 《Journal of medicinal chemistry》1992,35(13):2363-2368
In the search for more selective A2-receptor agonists and on the basis that appropriate substitution at C2 is known to impart selectivity for A2 receptors, 2-alkynyladenosines 2a-d were resynthesized and evaluated in radioligand binding, adenylate cyclase, and platelet aggregation studies. Binding of [3H]NECA to A2 receptors of rat striatal membranes was inhibited by compounds 2a-d with Ki values ranging from 2.8 to 16.4 nM. 2-Alkynyladenosines also exhibited high-affinity binding at solubilized A2 receptors from human platelet membranes. Competition of 2-alkynyladenosines 2a-d for the antagonist radioligand [3H]DPCPX and for the agonist [3H]CCPA gave Ki values in the nanomolar range, and the compounds showed moderate A2 selectivity. In order to improve this selectivity, the corresponding 2-alkynyl derivatives of adenosine-5'-N-ethyluronamide 8a-d were synthesized and tested. As expected, the 5'-N-ethyluronamide derivatives retained the A2 affinity whereas the A1 affinity was attenuated, resulting in an up to 10-fold increase in A2 selectivity. A similar pattern was observed in adenylate cyclase assays and in platelet aggregation studies. A 30- to 45-fold selectivity for platelet A2 receptors compared to A1 receptors was found for compounds 8a-c in adenylate cyclase studies. 相似文献
119.
本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。 相似文献
120.
目的 分析超声各特征性影像表现在乳腺浸润性导管癌中的诊断价值。方法 选取解放军总医院第六医学中心 2018-01至2019-12两年内收治的 135例乳腺浸润性导管癌患者纳入本研究,分析乳腺浸润性导管癌的超声影像特征、体检自检发现率以及淋巴结转移与病变大小、位置的相关性。结果 (1)单因素分析显示:形态不规则(91.11%)、边界不清楚(64.44%)、血流信号(44.44%)、微钙化(37.78%)、纵横比>1(17.78%)、后方回声衰减(15.56%)超声诊断指标,与浸润性导管癌的诊断具有相关性;(2)与其他三个象限相比较,内上象限浸润性导管癌更容易被患者自检发现,占自检发现病例的34.93%;(3)内上象限及外上象限的浸润性导管癌更容易发生淋巴结转移(转移率为:内上:25.53%,内下:0.00%,外上:64.70%,外下:11.76%);(4)对<3 cm的浸润性导管癌,其大小与腋窝淋巴结的转移没有相关性。结论 超声表现以形态不规则在乳腺浸润性导管癌中的发生率最高,且在早期病变中即表现出来;乳腺病变的自检检出率、乳腺癌淋巴转移率均与乳腺病变的大小和位置密切相关。 相似文献