Ablation definition

Ablation rate constant definition, 418 determination, 414,417f Ablative photodecomposition description, 411 See also Photoablation Ace ty la ted m-cresol—novolac copolymers, preparation, 193... 

Thermal ablation using carbon nanotubes is a definite option for use in oncology, especially since nanotubes can be functionalized with targeting modalities like folic acid. Some cancer cell types express large numbers of folic acid receptors on... 

Flecainide slows conduction in all cardiac cells including the anomalous pathways responsible for the Wolff-Parkinson-White (WPW) syndrome. Together with encainide and moricizine, it underwent clinical trials to establish if suppression of asymptomatic premature beats with antiarrhythmic drugs would reduce the risk of death from arrhythmia after myocardial infarction. The study was terminated after preliminary analysis of 1727 patients revealed that mortality in the groups treated with flecainide or encainide was 7.7% compared with 3.0% in controls. The most likely explanation for the result was the induction of lethal ventricular arrhythmias possibly due to ischaemia by flecainide and encainide, i.e. a proarrhythmic effect. In the light of these findings the indications for flecainide are restricted to patients with no evidence of structural heart disease. The most common indication, indeed where it is the drug of choice, is atrioventricular re-entrant tachycardia, such as AV nodal tachycardia or in the tachycardias associated with the WPW syndrome or similar conditions with anomalous pathways. This should be as a prelude to definitive treatment with radiofrequency ablation. Flecainide may also be useful in patients with paroxysmal atrial fibrillation. 

The answer is a. (Murray, pp 812-828. Scriver, pp 3-45. Sack, pp 97-158. Wilson, pp 23—39.) Females have two alleles for each locus on the X chromosome because of their 46,XX karyotype. One normal allele is by definition sufficient for normal function in X-linked recessive disorders, so that females with one abnormal allele are carriers instead of affected individuals. Only when the companion normal allele is disrupted or missing does the abnormal allele cause disease. The Lyon hypothesis predicts that X inactivation is early, irreversible, and random, but some females inactivate only the X chromosome carrying the normal allele. X autosome translocations may disrupt an X chromosome locus and cause disease because the translocated autosome must remain active to avert embryonic death nonrandom inactivation of the normal X chromosome thus ablates expression of its normal allele. Females with Turner s syndrome, like males with 46,XY karyotypes, have only one X chromosome and can be affected with X-linked recessive diseases. Conversely, females with triple X or trisomy X syndrome have three alleles at each X chromosome locus and are not affected with X-linked recessive disorders. Since choices c, d, and e each require two genetic changes, they are less common than choice a. 

Procedural success rates for AF ablation depend on numerous factors, including type of AF (paroxysmal, persistent, or long-lasting persistent), clinical and anatomic considerations, ablation technique, and definition... 

For an understanding of polymer ablation the main ablation parameters have to be explained and their definition have to be discussed in detail. Also, the most frequently proposed ablation mechanisms and models will be discussed. 

Although remission of Graves disease does occur, experience in the U.S. suggests that this happens in less than 50 fo of patients. Thus, many endocrinologists in the U.S. prefer radioactive iodine ablation for definitive therapy (see below). 

Chemical ablation is classified based on the used agent, such as ethanol, or acetic acid. By definition, chemical ablation induces coagulation necrosis and tumor ablation. Ethanol ablation is also called percutaneous ethanol instillation (PEI), percu-... 

In terms of guidelines no definite recommendations exist yet regarding those specific properties that make a lesion suitable for RFA. Nevertheless, based on the electrophysiological characteristic of the RFA systems, the electrode design and last but not least on oncological considerations, special thought has to be given to the size and localization of a lesion in order to achieve complete ablation (Kuvshinoff and Ota 2002). 

The burns noted had occurred within a period of 5 months and no further burns except one first-degree burn in a lung patient with multiple metasta-ses treated and an ablation time over 2 h were noted thereafter, although we have not changed the ablation protocol - thus malfunctioning of the pads cannot definitely be ruled out. 

Renal scarring secondary to vesicoureteral reflux may be the cause of renovascular hypertension. Renal ablation is an alternative to nephrectomy to remove to involved kidney. The selective embolization should be performed with alcohol to prevent collateral revascularization. The efficacy is debated considering that embolization may delay the definitive treatment [26]. Gelfoam and coils are less valuable than alcohol because of collateral revascularization (Fig. 23.9a,b). 

---