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991.
Amiodarone is a heavily iodinated drug effective in the control of various tachyarrhythmias. Despite its undoubted benefit, treatment with amiodarone is not without risk, because a number of potentially serious side-effects may develop during therapy. Thyrotoxicosis is most commonly recognised but its potential consequences tend to be underestimated, and its treatment can be challenging and difficult. We report several cases of amiodarone-induced thyrotoxicosis which serve to highlight the potential severity of the condition. 相似文献
992.
993.
Background
Management of high-grade T1 (formerly T1G3) bladder cancer continues to be controversial. Should patients with T1G3 bladder cancer have an immediate radical cystectomy or should they receive intravesical bacillus Calmette-Guérin preserving bladder? Gemcitabine and cisplatin (GC) adjuvant chemotherapy may help to strike a balance between intravesical and early cystectomy. For purposes of this study, we continue to refer high-grade T1 lesion as “T1G3.”Objective
To evaluate the characteristics and the long-term outcome of GC adjuvant chemotherapy in T1G3 bladder cancer after transurethral resection of bladder tumor (TURBT).Materials and methods
We, retrospectively, reviewed 48 patients who were newly diagnosed with T1G3 bladder cancer between January 2009 and December 2012. A total of 48 patients received 4 cycles of GC adjuvant chemotherapy after TURBT. One month after 4 cycles of GC adjuvant chemotherapy, response was evaluated by re-TURBT. Median follow-up was 59.5 (range: 18–70) months, all patients have been observed for more than 3 years. Salvage cystectomy was recommended for patients with persistent disease and for tumor progression after initial complete response.Result
Complete response was achieved in 44 (91.7%) patients. Of complete responders, 5 patients experienced recurrence and 5 patients showed progression. The progression rate and disease-specific survival rate were 10.4% and 91.7% at 3 years, respectively. More than 80% of survivors preserved their bladder. Kaplan-Meier curves showed that concomitant carcinoma in situ (CIS) was the only factor that had an influence on progression-free survival (P = 0.022) and disease-specific survival (P = 0.017). Concomitant CIS was the prognostic factor for progression rate and disease-specific survival rate at 3 years (P = 0.008 and P = 0.035).Conclusion
GC adjuvant chemotherapy is a safe conservative treatment for T1G3 bladder cancer, but effective is really a phase II study. Patients with T1G3 bladder cancer with concomitant CIS should be treated more aggressively because of the high risk of progression. 相似文献994.
胶原海绵复合新生大鼠原代心肌细胞构建工程化心肌组织 总被引:2,自引:2,他引:2
目的:探索以胶原海绵为支架、新生大鼠原代心肌细胞为种子细胞,于体外构建工程化心肌组织的方法。方法:实验于2005-12/2006-11在解放军第四军医大学西京医院心内科实验室完成。Ⅰ型胶原海绵剪切成方形片状(2.0cm×1.4cm×0.2cm),经60Co照射消毒,于DMEM培养液中水化1h左右。另取1d龄SD大鼠心脏,剪成小碎块,然后用2.5g/L胰蛋白酶于37℃中消化,吸取上清至含胎牛血清的DMEM中,重复消化四五次,用差速贴壁法除去大部分成纤维细胞,将细胞沉淀用DMEM培养液以2×109L-1的密度悬浮备用。将上述的心肌细胞悬液1mL缓慢滴注于玻璃模型中的胶原海绵上,然后置于细胞培养中培养。肉眼及显微镜主要观察工程化心肌组织在培养期间的自发收缩情况,包括收缩的部位、强度、频率、一致性以及收缩随时间变化的情况。苏木精-伊红染色观察工程化心肌组织内胶原纤维的变化,细胞形态,胞核的形状及细胞之间的连接。免疫组织化学染色和透射电镜观察工程化心肌组织片的形态和功能。结果:①细胞接种于胶原海绵上1d后,细胞/胶原复合物的凝胶化过程基本完毕,体积保持恒定,维持至培养结束,第3天细胞/胶原复合物局部出现点片状自发收缩,第5天整个细胞/胶原复合物出现同步化自发收缩,收缩频率61~199次/min。2周后37.5%的工程化心肌组织的自发收缩活动减弱,但75%的工程化心肌组织的自发收缩活动持续至培养结束。②苏木精-伊红染色、免疫组织化学染色和透射电子显微镜显示,工程化心肌组织内细胞间连接广泛存在,细胞多呈纵向分布,胞核呈长圆形,胞浆内α-肌节肌动蛋白阳性,胞内肌原纤维排列整齐,可见到心肌特异性的肌小节结构和Z线,多数细胞具有分化的心肌细胞表型。结论:用新生大鼠原代心肌细胞为种子细胞、以Ⅰ型胶原海绵为支架材料,构建出的工程化心肌组织,于体外可长时间持续自发收缩,该细胞/胶原复合物的形态结构与生理功能均类似于成熟大鼠心肌组织。 相似文献
995.
Leung N 《Expert review of anti-infective therapy》2004,2(2):173-180
Lamivudine (Epivir, GlaxoSmithKline) was approved by the US Food and Drug Administration for the treatment of adult patients with chronic hepatitis B in 1998, and has since been shown to be of benefit to selected patients with chronic hepatitis B. Drug resistance is the main issue encountered during therapy, with lamivudine resistant mutants emerging at a rate of approximately 15 to 30% per year of therapy. These mutants are associated with relapse of hepatitis, and occasionally hepatic decompensation. Despite this, therapeutic indications and guidelines for lamivudine therapy have now been drawn up, which indicate that lamivudine will be the first line therapy for hepatitis B e antigen-positive chronic hepatitis B patients, although its role in hepatitis B e antigen-negative patients remains controversial. 相似文献
996.
Randy O. Frost Kristin Lynn Trepanier Elissa J. Brown Richard G. Heimberg Harlan R. Juster Gregory S. Makris Anna W. Leung 《Cognitive therapy and research》1997,21(2):209-222
Subjects high and low in perfectionistic concern over mistakes (CM; Frost, Marten, Lahart, & Rosenblate, 1990) monitored their mistakes daily to test several hypotheses about the nature of mistakes among perfectionists. High-CM subjects did not report a greater number of mistakes, nor were the mistakes reported by high- and low-CM subjects different in quality, based on ratings by independent judges. However, there were differences in personal reactions to mistakes, perceptions of the seriousness of mistakes, beliefs about other peoples' reactions to mistakes, and rumination about mistakes. High-CM subjects reacted more strongly and more negatively to their mistakes. The specific nature of these findings and implications for cognitive-behavioral treatment of perfectionism are discussed. 相似文献
997.
目的:介绍言语流畅性的测量工具,考察言语流畅性与记忆之间的关系,探讨言语流畅性的神经生理基础。资料来源:应用计算机检索Sciencedirect 1975-07/2005-05中与言语流畅性相关的文献,检索词为“verbal fluency”,限定文章语言种类为英文。资料选择:对资料进行初审,选取文章标题中含有“verbal fluency”的英文文献。纳入标准:①对言语流畅性测量任务的研究。②对言语流畅性与记忆的研究。③对言语流畅性神经生理基础的研究。资料提炼:共收集到651篇关于言语流畅性的文章,纳入30篇用于本综述。资料综合:测量言语流畅性的任务主要分为简单任务(包括音位流畅性任务和语义流畅性任务)与复杂任务(包括可能工作、替代使用、草拟、推断、物品制作以及新的使用方法等)。言语流畅性任务的完成主要涉及到记忆搜索的过程,另外,精细组织的语义网络系统对于言语流畅性任务来说也是非常重要的。言语流畅性的神经生理基础包括了总体基础,前额叶,海马以及大脑两半球的不对称性。结论:言语流畅性作为人类语言基本技能的一项指标,对语言认知研究具有极其重要的意义。它不仅是神经心理研究的一项非常重要的检测和诊断指标,也是一种研究人类心理的非常有用的研究工具,是探索人类语言与认知、创造之迷进而探索人类意识之迷的钥匙。 相似文献
998.
Telavancin, a multifunctional lipoglycopeptide, disrupts both cell wall synthesis and cell membrane integrity in methicillin-resistant Staphylococcus aureus 总被引:5,自引:0,他引:5
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Higgins DL Chang R Debabov DV Leung J Wu T Krause KM Sandvik E Hubbard JM Kaniga K Schmidt DE Gao Q Cass RT Karr DE Benton BM Humphrey PP 《Antimicrobial agents and chemotherapy》2005,49(3):1127-1134
The emergence and spread of multidrug-resistant gram-positive bacteria represent a serious clinical problem. Telavancin is a novel lipoglycopeptide antibiotic that possesses rapid in vitro bactericidal activity against a broad spectrum of clinically relevant gram-positive pathogens. Here we demonstrate that telavancin's antibacterial activity derives from at least two mechanisms. As observed with vancomycin, telavancin inhibited late-stage peptidoglycan biosynthesis in a substrate-dependent fashion and bound the cell wall, as it did the lipid II surrogate tripeptide N,N'-diacetyl-L-lysinyl-D-alanyl-D-alanine, with high affinity. Telavancin also perturbed bacterial cell membrane potential and permeability. In methicillin-resistant Staphylococcus aureus, telavancin caused rapid, concentration-dependent depolarization of the plasma membrane, increases in permeability, and leakage of cellular ATP and K(+). The timing of these changes correlated with rapid , concentration-dependent loss of bacterial viability, suggesting that the early bactericidal activity of telavancin results from dissipation of cell membrane potential and an increase in membrane permeability. Binding and cell fractionation studies provided direct evidence for an interaction of telavancin with the bacterial cell membrane; stronger binding interactions were observed with the bacterial cell wall and cell membrane relative to vancomycin. We suggest that this multifunctional mechanism of action confers advantageous antibacterial properties. 相似文献
999.
目的:观察碱性成纤维细胞生长因子对大鼠脑出血后出血灶周围脑组织和出血侧海马bax、bcl-2基因表达的影响,探讨神经营养因子对神经细胞调亡的调控。方法:实验于2006-01/10在广西医科大学医学科学实验中心完成。①取成年清洁级Wistar大鼠72只,雌雄各半,体质量250g左右。②采用脑内囊注射胶原酶建立大鼠脑出血模型,动物于苏醒后按Bederson法进行神经病学评分,评分>3分后入选本实验,入选72只大鼠随机抽签法分为3组,每组24只。碱性成纤维细胞生长因子组按8μg/kg剂量肌肉注射,1次/d;生理盐水组肌肉注射等剂量的生理盐水,1次/d;模型组不作任何干预。③每组分别于干预后1,3,7d随机抽取8只大鼠,麻醉状态下取出血灶周围脑组织和出血侧海马,采用半定量反转录-聚合酶链反应检测调亡调控基因bax mRNA,bcl-2mRNA的表达。结果:在建立脑出血模型中共5只大鼠死亡,随后对死亡动物进行解剖,发现脑内血肿量过大,致脑疝形成而导致死亡,后随机补充动物。72只大鼠进入结果分析。①血肿周围脑组织bax mRNA表达:干预后3d,7d,碱性成纤维细胞生长因子组血肿周围脑组织bax mRNA表达比生理盐水组明显减少(3d:0.54±0.19,0.76±0.23,P<0.05;7d:0.45±0.19,0.71±0.16,P<0.01)。②血肿周围脑组织bcl-2mRNA表达:干预后3d,7d,碱性成纤维细胞生长因子组的血肿周围脑组织bcl-2mRNA表达比生理盐水组明显增高(3d:0.68±0.25,0.39±0.19,P<0.05;7d:0.80±0.21,0.48±0.18,P<0.01)。③出血侧海马bax mRNA表达:干预后3d和7d,碱性成纤维细胞生长因子组的出血侧海马bax mRNA表达比生理盐水组均明显减少(3d:0.54±0.18,0.70±0.11;7d:0.43±0.24,0.69±0.18,P均<0.05)。④出血侧海马bcl-2mRNA表达:干预后3d和7d,碱性成纤维细胞生长因子组的出血侧海马bcl-2mRNA表达比生理盐水组均明显增多(3d:0.66±0.11,0.50±0.15;7d:0.72±0.12,0.52±0.22,P均<0.05)。结论:碱性成纤维细胞生长因子能调节凋亡相关基因,提高大鼠脑出血后大脑脑组织和海马bcl-2mRNA的表达,降低bax mRNA的表达。 相似文献
1000.
Molecular characterization of quinolone-resistant Neisseria gonorrhoeae in Hong Kong 总被引:2,自引:0,他引:2
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Kam KM Kam SS Cheung DT Tung VW Au WF Cheung MM 《Antimicrobial agents and chemotherapy》2003,47(1):436-439
In Hong Kong, ParC changes among high-level quinolone-resistant Neisseria gonorrhoeae (QRNG) isolates at Ser-87-->Arg were associated with a higher level of resistance than a Ser-87-->Ile alteration. Two previously undescribed mutations in clinical isolates occurring in gyrA, conferring Ala-92-->Pro and Asp-95-->Tyr changes, were detected. Nine different outer membrane lipoprotein (Lip) repeat classes-11 to 19 repeats-were identified, with repeat lengths of 16 and 17 the most common, indicating considerable strain diversity. 相似文献