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91.
Summary Bis--diketonato complexes of titanium, zirconium, and hafnium were tested against autochthonous colorectal tumors in rats. The model was found to reflect the clinical situation most closely. of the compounds tested, budotitane was the most effective in terms of decrease in tumor weight and number and in increasing the lifespan of the treated animals. The therapeutic efficiency was superior to that of 5-fluorouracil, which so far has been the drug with the best activity in patients suffering from colon cancer.Abbreviations Ti(bzac)2Cl2 dichlorobis(1-phenylbutane-1,3-dionato)-titanium(IV) - Ti(bzac)2(OEt)2, budotitane, (INN) diethoxybis(1-phenylbutane-1,3-dionato)-titanium(IV) - Zr(bzac)2Cl2 dichlorobis(1-phenulbutane-1,3-dionato)-zirconium(IV) - Hf(bzac)2Cl2 dichlorobis(1-phenylbutane-1,3-dionato)-hafnium(IV) - AMMN acetoxymethylmethylnitrosamine; 5-FU - 5-FU 5-Fluorouracil - DFUR 5-deoxy-5-fluorouridine - CPA cyclophosphamide - cis-DDP, Cisplatin cis-diamminedichloroplatinum(II) - INN international nonproprietary name Dedicated to Professor Norbert Brock on the occasion of his 75th birthday  相似文献   
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OBJECTIVES

To assess the clinical significance of inducible ventricular tachyarrhythmias among patients with unexplained syncope.

BACKGROUND

Induction of sustained ventricular arrhythmias at electrophysiology study in patients with unexplained syncope and structural heart disease is usually assigned diagnostic significance. However, the true frequency of subsequent spontaneous ventricular tachyarrhythmias in the absence of antiarrhythmic medications is unknown.

METHODS

In a retrospective case-control study, the incidence of implantable cardiac defibrillator (ICD) therapies for sustained ventricular arrhythmias among patients with unexplained syncope or near syncope (syncope group, n = 22) was compared with that of a control group of patients (n = 32) with clinically documented sustained ventricular tachycardia (VT). Sustained ventricular arrhythmias were inducible in both groups and neither group received antiarrhythmic medications. All ICDs had stored electrograms or RR intervals. Clinical variables were similar between groups except that congestive cardiac failure was more common in the syncope group.

RESULTS

Kaplan-Meier analysis of the time to first appropriate ICD therapy for syncope and control groups produced overlapping curves (p = 0.9), with 57 ± 11% and 50 ± 9%, respectively, receiving ICD therapy by one year. In both groups, the induced arrhythmia was significantly faster than spontaneous arrhythmias, but the cycle lengths of induced and spontaneous arrhythmias were positively correlated (R = 0.6, p < 0.0001). During follow-up, three cardiac transplantations and seven deaths occurred in the syncope group, and two transplantations and five deaths occurred in the control group (36-month survival without transplant 52 ± 11% and 83 ± 7%, respectively, p = 0.03).

CONCLUSIONS

In patients with unexplained syncope, structural heart disease and inducible sustained ventricular arrhythmias, spontaneous sustained ventricular arrhythmias occur commonly and at a similar rate to patients with documented sustained VT. Thus, electrophysiologic testing in unexplained syncope can identify those at risk of potentially life-threatening tachyarrhythmias, and aggressive treatment of these patients is warranted.  相似文献   

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目的:观察双源性并行心律的心电散点图特征,探讨其鉴别诊断的意义。方法:选择已明确诊断的7例双源性并行心律患者的心电散点图资料进行回顾性分析,分别与单源性早搏、双源性早搏及单源性并行心律的心电散点图特征进行对比。结果:共分为6组(每组各7例),其特征是:1组(单源性房性早搏),呈三分布,窦性节律位于45°线上;2组(双源性房性早搏)呈五分布,窦性节律位置不变,早搏前后点分别位于其两边,图形对称呈双分布,1、2组B线斜率均在0-1之间,其斜率无显著差异(P>0.05);3组(单源性室性早搏),呈四分布图形,窦性节律位于45°线上,早搏前后点分别趋向平行于X、Y轴,4组(双源性室性早搏)呈六分布,窦性节律位置不变,与单源性室早不同之处在于,其早搏前后点呈对称双分布,3、4组B线斜率均趋向于0,其斜率也无显著差异( P>0.05);5组(单源性并行心律)图形特征为沿垂直于45°线的四分布图形,早搏点集垂直于45°线,早搏前点、后点集分别垂直于X、Y轴;6组(双源性并行心律)图形为沿垂直于45&#176;线的七分布图形,图形与单源性并行心律相似,5、6组间B线斜率均趋向于∞,无显著差异(P>0.05),不同之处在于呈双分布;5、6组B线斜率明显大于1、2组[(∞)比(4.78±0.19)],1、2组B线斜率又显著大于3、4组(0.36±0.06), P均<0.01。结论:双源性并行心律心电散点图特征与单源性并行心律,单(双)源性房、室早搏图形均有显著差异,有助于并行心律的鉴别诊断。  相似文献   
95.
The reaction of 2,6-diformyl-4-methylphenol (DFMF) with 1-amino-2-propanol (AP) and tris(hydroxymethyl)aminomethane (THMAM) was investigated in the presence of Cobalt(II) salts, (X = ClO4, CH3CO2, Cl, NO3), sodium azide (NaN3), and triethylamine (TEA). In one pot, the variation in Cobalt(II) salt results in the self-assembly of dinuclear, tetranuclear, and H-bonding-directed polynuclear coordination complexes of Cobalt(III), Cobalt(II), and mixed-valence CoIICoIII: [Co2III(H2L1)2(AP1)(N3)](ClO4)2 (1), [Co4(H2L1)23-1,1,1-N3)2(µ-1,1-N3)2Cl2(CH3OH)2]·4CH3OH (2), [Co2IICo2III(HL2)2(µ-CH3CO2)23-OH)2](NO3)2·2CH3CH2OH (3), and [Co2IICo2III (H2L12)2(THMAM−1)2](NO3)4 (4). In 1, two cobalt(III) ions are connected via three single atom bridges; two from deprotonated ethanolic oxygen atoms in the side arms of the ligands and one from the1-amino-2-propanol moiety forming a dinuclear unit with a very short (2.5430(11) Å) Co-Co intermetallic separation with a coordination number of 7, a rare feature for cobalt(III). In 2, two cobalt(II) ions in a dinuclear unit are bridged through phenoxide O and μ3-1,1,1-N3 azido bridges, and the two dinuclear units are interconnected by two μ-1,1-N3 and two μ3-1,1,1-N3 azido bridges generating tetranuclear cationic [Co4(H2L1)23-1,1,1-N3)2(µ-1,1-N3)2Cl2(CH3OH)2]2+ units with an incomplete double cubane core, which grow into polynuclear 1D-single chains along the a-axis through H-bonding. In 3, HL2− holds mixed-valent Co(II)/Co(III) ions in a dinuclear unit bridged via phenoxide O, μ-1,3-CH3CO2, and μ3-OH bridges, and the dinuclear units are interconnected through two deprotonated ethanolic O in the side arms of the ligands and two μ3-OH bridges generating cationic tetranuclear [Co2IICo2III(HL2)2(µ-CH3CO2)23-OH)2]2+ units with an incomplete double cubane core. In 4, H2L1−2 holds mixed-valent Co(II)/Co(III) ions in dinuclear units which dimerize through two ethanolic O (μ-RO) in the side arms of the ligands and two ethanolic O (μ3-RO) of THMAM bridges producing centrosymmetric cationic tetranuclear [Co2IICo2III (H2L12)2(THMAM−1)2]4+ units which grow into 2D-sheets along the bc-axis through a network of H-bonding. Bulk magnetization measurements on 2 demonstrate that the magnetic interactions are completely dominated by an overall ferromagnetic coupling occurring between Co(II) ions.  相似文献   
96.
BackgroundRemoval of biliary Fully Covered Self Expandable Metal Stents can fail due to stent migration and/or hyperplastic ingrowth/overgrowth.MethodsA case series of 5 patients with benign biliary strictures (2 post-cholecystectomy, 2 following liver transplantation and 1 related to chronic pancreatitis) is reported. The biliary stricture was treated by temporary insertion of Fully Covered Self Expandable Metal Stents. Stent removal failed due to proximal stent migration and/or overgrowth. Metal stent removal was attempted a few weeks after the insertion of another Fully Covered Metal Stent into the first one.ResultsThe inner Fully Covered Self Expandable Metal Stent compressed the hyperplastic tissue, leading to the extraction of both the stents in all cases. Two complications were reported as a result of the attempt to stents removal (mild pancreatitis and self-limited haemobilia).ConclusionIn the present series, the “SEMS in SEMS” technique revealed to be effective when difficulties are encountered during Fully Covered Self Expandable Metal Stents removal.  相似文献   
97.
《Research in microbiology》2014,165(7):490-500
A novel halophilic bacterium, strain RHS90T, was isolated from marine sediments from the Gulf of Lions, in the Mediterranean Sea. Its metabolic and physiological characteristics were examined under various cultural conditions, including exposure to stressful ones (oligotrophy, high pressure and high concentrations of metals). Based on phylogenetic analysis of the 16S rRNA gene, the strain was found to belong to the genus Halomonas in the class Gammaproteobacteria. Its closest relatives are Halomonas axialensis and Halomonas meridiana (98% similarity). DNA–DNA hybridizations indicated that the novel isolate is genotypically distinct from these species. The DNA G + C content of the strain is 54.4 mol%. The main fatty acids (C18:1 ω7c, 2-OH iso-C15:0, C16:0 and/or C19:0 cyclo ω8c), main polar lipids (diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified phosphoglycolipid) and major respiratory quinone (ubiquinone Q9) were determined. The novel isolate is heterotrophic, mesophilic, euryhaline (growth optimum ranging from 2 to 8% w/v NaCl) and is able to grow under stressful conditions. The strain accumulates poly-β-hydroxyalkanoates granules and compatible solutes. Based on genotypic, chemotaxonomic and phenotypic distinctiveness, this isolate is likely to represent a novel species, for which the name Halomonas lionensis is proposed. The type strain of H. lionensis is RHS90T (DSM 25632T = CIP 110370T = UBOCC 3186T).  相似文献   
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100.
目的:探讨应用磁导航遥控导管消融治疗右心室流出道起源的室性心动过速/室性早搏( RVOT-VT/PVCs)的安全性和有效性。方法2008年11月至2009年11月,在南京医科大学第一附属医院心血管内科行体表心电图检查,诊断为RVOT-VT/PVCs的患者共16例[女12例,男4例,平均年龄(44±15)岁],结合应用非接触标测系统和起搏标测确定靶点,磁导航遥控磁导管实施消融术,消融失败者改为手控导管消融。结果10例(63%)患者使用磁导航消融成功,6例需手控导管消融,1例术后出现动静脉瘘。平均放电(3.9±1.6)次,放电时间(240±33) s,总手术时间为(190±42) min,总X线曝光时间为(4.8±2.6) min,术者X线曝光时间平均为(3.2±2.0) min,磁导航系统遥控导管X线曝光时间为(1.6±1.0) min。结论应用磁导航系统结合非接触标测系统可安全、有效地实施遥控导管消融治疗RVOT-VT/PVCs,并可减少术者和患者的X线曝光时间。  相似文献   
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