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81.
A patient with resistant ventricular tachycardia treated with a combination of antiarrhythmic agents is described. Sudden onset of a wide complex ventricular rhythm with periods of asystole and failure to achieve transvenous pacing were observed, presumably due to antiarrhythmic drug toxicity. Inability to pace was reversed by the infusion of isoproterenol.  相似文献   
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Patients with trisomic Down’s syndrome were found to have significantincreases of acid phosphatase, alkaline phosphatase, and glucose-6-phosphatedehydrogenase in both lymphocytes and polymorphonuclear leukocytes separated from white blood cells by the procedure of Rabinowitz. The alterationin enzyme activities appears not to be directly related to genes located on thechromosome causing Down’s syndrome.

Submitted on March 2, 1967 Accepted on April 13, 1967  相似文献   
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ABSTRACT A cross-sectional analysis of characteristics possibly associated with congestive heart failure (CHF) was performed among 644 men, all 67 years of age and randomly selected from the general population. A total of 13% had symptoms and signs of overt CHF. Another 10% had early or “latent” CHF. Among overt CHF cases, 46% had hypertension, 55% coronary heart disease and 79% any one of these conditions. Among “latent” CHF cases, the corresponding proportions were 52%, 25 % and 65 %. Simple indices of left ventricular diastolic function and filling pressure as well as of pulmonary artery pressure were closer related to the CHF stage, than were measures of systolic left ventricular function. Smoking habits, hypertension, blood lipids, weight and other measures of body fat, blood glucose, and serum insulin were all correlated to CHF stage. In a multivariate analysis, smoking habits, hypertension, body weight, and serum insulin were independently and significantly correlated to CHF stage.  相似文献   
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In an effort to explore the effect of ring size on the biologically active conformation of cyclic analogs of the mating pheromone α-factor (WHWLQLKPGQPMY) from Saccharomyces cerevisiae, eight cyclic tetrapeptides corresponding to the KPGQ portion of α-factor were synthesized. These N-α-acetyl/carboxyl amide terminal cyclic tetrapeptides were prepared on a 4-methylbenzhydrylamine resin using orthogonal Boc, Frnoc, OFm and OtBut protecting groups and HOBt-DIPC accelerated active esters or urethane-protected N-carboxyanhydrides. On-resin cyclization of the side-chain amino and carboxyl groups of the first and fourth residues, respectively, was performed with the BOP reagent to generate lactams containing 14–18 atoms. HF cleavage resulted in two products, the desired cyclic tetrapeptide and a major side product. All peptides were purified to near homogeneity (>99%) by using reversed-phase HPLC and were characterized by FABMS and 1H NMR. Certain constrained cyclic tetrapeptides appear to be a mixture of isomers at room temperature as evidenced by HPLC and NMR. The major side product has been identified as a cyclo dimer, obtained as a consequence of interchain cyclization on the resin. CD analysis in several solvents gives evidence that some of the cyclic tetrapeptides exist in β-turn conformations. © Munksgaard 1995.  相似文献   
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