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The immunology of psoriasis 总被引:14,自引:0,他引:14
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Pseudo-Oversensing of the T Wave by an Implantable Cardioverter Defibrillator: A Nonclinical Problem
DAVID W. FRAZIER MARSHALL S. STANTON 《Pacing and clinical electrophysiology : PACE》1994,17(7):1311-1315
Two patients are described who had pseudo-oversensing of T waves during follow-up testing of the Medtronic PCD. Each patient exhibited appropriate T wave sensing following closely coupled spontaneous QRS complexes to subthreshold stimuli without having T wave sensing following sensed or paced complexes. One patient also revealed T wave sensing following fusion beats. The occurrence of T wave sensing in these unique clinical situations was due to the auto-adjusting sensitivity threshold function used by the PCD. Recognition of this normal sensing function will prevent inappropriate reprogramming of the sensitivity or postpace refractory period, interventions that could potentially lead to ventricular tachyarrhythmia undersensing. 相似文献
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SESHA NATARAJAN STEPHEN M. FESTIN ANDERS HEDBERG EDDIE C.-K. LIU DAVID M. FLOYD JOHN T. HUNT 《Chemical biology & drug design》1992,40(6):567-574
We have developed an expeditious method for the incorporation of the biotinylaminocaproyl moiety on the ε-amino group of a lysine residue within a peptide chain in a site-specific manner. Using t-Boc chemistry for the solid phase synthesis approach and a base labile, acid stable protecting group (Fmoc-) for the ε-amino group of the target lysine, we prepared fully protected resin bound peptides which are site-specifically biotinylated. Following HF cleavage, the uniquely biotinylated peptides were obtained in a high degree of purity. Using this approach, a number of biotinylaminocaproyllysyl derivatives of a monocyclic Endothelin-1 analog were prepared. Synthesis of selected bicyclic analogs of high affinity monocycles led to the preparation of the bicyclic [Nle7]ET-1 analog containing ε-biotinylaminocaproyllysine at position-9. This peptide, with Kd= 0.08 nM, has 1000-fold higher affinity for the ETA receptor than the commercially available Nα-biotinylated Endothelin-1. The general utility of this biotinylation methodology was demonstrated by the synthesis of a site-specifically biotinylated PTH analog which contained several side chain functionalized amino acid residues in its sequence. The synthetic method reported here is convergent in that it allows the facile variation of the length of the spacer and also offers the potential to introduce in a site specific manner other groups such as affinity labels and fluorescent tags. 相似文献
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HIROSHI KATAOKA JORGE P. LI ALFRED S.T. LUI STEVEN J. KRAMER DAVID A. SCHOOLEYS 《Chemical biology & drug design》1992,39(1):29-35
The locations of the three disulfide bonds of eclosion hormone (EH) isolated from Manduca sexta were assigned by sequence analysis of thermolysin fragments and by comparison of a key heterodimeric fragment to regiospecifically synthesized parallel and antiparallel isomers. We elucidated the complete structure of Manduca EH as a 62-residue peptide which has three disulfide bonds between Cys14-Cys38, Cys18-Cys34, and Cys21-Cys49. 相似文献
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Well-being is frequently said to be the ultimategoal of health promotion. However, health promotion author itiesdo no: offer a clear definition of well-being.Instead health promoters either assume a causal relationshipbetween their activities and the increase of well-beingor claim privileged knowledge of well-being andits means of production, or both. These health promotion strategiesare questioned, and it is suggested that the use of well-beingin health promotion acts to obscure the analysis of health promotionphilosophy and practice. It is concluded that either the termwell-being should be given clear and substantialcontent, or it should be discarded by health promoters. Thelatter option is favoured. 相似文献