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21.
Three males infected with the human immunodeficiency virus (HIV) were noted to have extensive flat warts of the face and/or body. In two there were also pityriasis versicolor-like lesions. Biopsies showed foamy, basophilic, distended cytoplasm in granular layer keratinocytes, characteristic of the human papillomavirus types seen in epidermodysplasia verruciformis. DNA hybridization techniques demonstrated the presence of HPV-type 8 in one patient and HPV 5 and 8 in another. Patients with immune suppression due to HIV infection may demonstrate the clinical features of epidermodysplasia verruciformis with the same potentially oncogenic HPV types.  相似文献   
22.
Abstract. Animal experiments have shown that acute respiratory acidosis stimulates water, Na and C1 absorption and HCO3 secretion in the ileum. The aim of this study was to investigate whether the human ileum also responds to changes in systemic acid-base balance. Seven healthy volunteers (mean age 24, range 21–29 years) underwent segmental ilea perfusion using a multi-lumen tube assembly with a proximal occluding balloon. A 30 cm test segment was perfused under steady state conditions with a plasma-like electrolyte solution containing PEG as a non-absorb-able volume marker. After a control period, respiratory acidosis (blood pCO2 56.2 mmHg, pH 7.29 and [HCO3] 26.4 mmol 1-1) was induced by CO2-breathing over a period of 50 min. Acute respiratory acidosis stimulated net HCO3 secretion in patients secreting HCO3 and reduced absorption in patients exhibiting net HCO3 absorption. These changes were immediate and appeared to be at least partly reversible. Net water, Na, K and CI movement were not affected. The data suggest that HCO3 transport in the human ileum responds to acute respiratory acidosis.  相似文献   
23.
Abstract. In the present study, the serum levels of the endotoxin-binding proteins transferrin, α2-macroglo-bulin and Gc-globulin were nephelometrically determined in the morning of the first day after surgical treatment of peritonitis. The aim was to determine whether the occurrence of organ failure can be predicted by the serum levels of the described proteins. A serum level of transferrin below 1.15 g 1-1 allows the prediction of organ failure with a sensitivity of 78.6% and a specificity of 81.8%. As in the case of α2-macroglobulin, sensitivity and specificity reached 67.8% and 72.7% respectively at a border level of 1.05 g 1-1. The predictive value of Gc-globulin, limit 0.2 g 1-1, was in the same range. So the serum levels of these proteins allow an early prediction of forthcoming organ failure in the course of peritonitis. Furthermore, these results support the significance of the endotoxin interaction with these proteins.  相似文献   
24.
We compared the functioning and life contexts of late-middle-aged adults classified as late-onset problem drinkers (n=229), early-onset problem drinkers (n=475), and nonproblem drinkers (n=609). Compared with nonproblem drinkers, late-onset problem drinkers consumed more alcohol and functioned more poorly; they also reported more negative life events and chronic stressors, fewer social resources, and more use of avoidance coping. However, late-onset problem drinkers consumed less alcohol, had fewer drinking problems, functioned better, and had more benign life contexts than did early-onset problem drinkers. We found no evidence of an association between age-related loss events and the onset of late-life drinking problems. Very few problem drinkers sought help specifically for their alcohol abuse, but about 25% did seek treatment from mental health practitioners. Problem drinkers who were functioning more poorly and who reported more life stressors and fewer social resources were more likely to seek help.  相似文献   
25.
Outcomes of Cardioversion Post AF Ablation.   Introduction: Early recurrence of atrial tachyarrhythmias is commonly noted after catheter ablation of atrial fibrillation (AF). The long-term outcomes of patients who require cardioversion for persistent AF after AF ablation is not known. This study reports the outcomes of patients who underwent cardioversion for persistent AF or atrial flutter following an AF ablation procedure.
Methods: The patient population comprised 55 patients (mean age 58 ± 10 years, 35% paroxysmal) who underwent catheter ablation of AF and subsequently required electrical cardioversion for persistent AF (45 patients) or atrial flutter (10 patients). Cardioversion was defined as early (within 90 days of the ablation procedure) or late (between 90 and 180 days following ablation).
Results: The mean follow-up duration was 15 ± 8 months. Forty-six of the 55 patients (84%) patients experienced recurrence during follow-up. The average time to recurrence after cardioversion was 37 days. Of the 55 patients, 8 (15%) patients had a complete success, 11 (20%) patients had a partial success and 36 patients (65%) had a failed outcome. Seven of the 43 patients (16%) who underwent early cardioversion had a complete success as opposed to one of 12 patients (8%) who underwent late cardioversion (P = 0.49).
Conclusions: This study shows that >80% of patients who undergo cardioversion for persistent AF or atrial flutter after AF ablation have recurrence. The timing of cardioversion did not affect the outcome. These findings allow clinicians to provide realistic expectations to patients regarding the long-term outcome and/or requirement for a second ablation procedure. (J Cardiovasc Electrophysiol, Vol. 21, pp. 27–32, January 2010)  相似文献   
26.
Effect of Obesity and OSA on Outcomes Post AF Ablation . Background: Obesity and obstructive sleep apnea (OSA) have a strong association with atrial fibrillation (AF). The purpose of this study was to prospectively determine the effects of obesity, assessed by the body mass index (BMI) and OSA on the efficacy of catheter ablation of AF. Methods: The patient population consisted of 109 patients (mean age: 60 ± 10 years, 79% male, 67% paroxysmal, mean BMI 28 ± 5 kg/m2) who underwent catheter ablation of AF. Based on BMI, patients were classified as normal (<25 kg/m2), overweight (≥25 and <30 kg/m2), or obese (≥30 kg/m2). OSA was assessed by the Berlin questionnaire. Clinical success was defined as at least 90% reduction in AF burden after 3‐month blanking period. Mean duration of follow‐up was 11 ± 4 months. Results: Of the 75 patients with clinical success, 25 (33%) had normal BMI, 29 (39%) were overweight, and 21 (28%) were obese. Among the 34 patients with failed outcome, 5 (15%) had normal BMI, 14 (41%) were overweight, and 15 (44%) were obese (P = 0.04). Twenty‐eight of the 48 patients with OSA (58%) had clinical success as opposed to 47 of the 61 patients (77%) without OSA (P = 0.036). On multivariate analysis, only BMI emerged as an independent predictor of procedural failure ((OR 1.11, CI: 1.00–1.21, P = 0.03). Conclusions: The results of this prospective study show that obesity, a modifiable risk factor, is an independent predictor of procedural failure after catheter ablation of AF. Whether treating obesity may improve the results of catheter ablation of AF warrants further investigation. (J Cardiovasc Electrophysiol, Vol. 21, pp. 521‐525, May 2010)  相似文献   
27.
Signal Averaged Intracardiac Electrograms. Introduction : In patients with manifest accessory pathways, Kent potentials are often difficult to identify even at sites of successful catheter ablation, due largely to signal noise and catheter instability. We hypothesized that signal averaging the intracardiac electrogram recorded from the ablation catheter over a number of beats would improve the signal-to-noise ratio of the electrogram and aid in the detection of Kent potentials at accessory pathway locations.
Methods and Results : We retrospectively analyzed distal-pair electrograms recorded from 9 successful, 6 transiently successful, and 10 failed ablation sites in 10 patients with manifest accessory pathways who underwent catheter ablation. We developed custom software to finely align 20 to 30 consecutive sinus beats and compute the signal average of the electrogram (SAE) for each site. Kent potentials were classified as probable, possible, or absent in the raw ablation site electrogram and the SAE base on morphologic criteria. A measure of beat-to-beat signal instability, the variability quotient (VQ), was also computed for each site. Probable Kent potentials were found in the raw ablation site electrogram at only 2 of the 15 successful and transiently successful sites, but were found in the SAE at 10 of these sites (P = 0.008). Eight of the 9 successful sites had VQ < 0.2, suggesting stable catheter-tissue contact, while 3 of the 6 transiently successful sites had VQ > 0.2, indicating unstable contact.
Conclusions : Signal averaging the intracardiac ablation site electrogram enhances detection of Kent potentials at accessory pathway locations. Catheter instability can be quantified by signal variability analysis and, when high, may predict lack of successful ablation even at sites where Kent potentials are present.  相似文献   
28.
For more than three decades, my colleagues and I have examined factors that help people overcome adversity, in particular how personal and treatment factors and the broader social context influence recovery from alcoholism. Guided by a demanding Guardian Angel, we have formulated conceptual models that raise key issues, developed tentative measures of key constructs, and conducted long-term naturalistic studies. In an ongoing odyssey of quest and discovery, we have identified interrelated factors that are important to predicting outcomes. These factors include personal resources and specific aspects of treatment, life context, and appraisal and coping. Such basic processes are also broadly relevant to remission and recovery from depression and other disorders. The answers to each question we have addressed point to more intriguing and complex issues to consider before vie with grasp the essence of why some people adapt to adversity so much better than others do.  相似文献   
29.
30.
Duodenopancreatectomy induces a severe glucagon deficiency and elevated plasma concentrations of alanine, aspartate, glycine, proline, serine, arginine, citrulline, ornithine, phenylalanine and tyrosine. Restoring high physiological plasma glucagon in six such patients by infusing 0.3 mg/24 h of exogenous glucagon reduced significantly (P less than 0.01 or 0.001) the mentioned amino acids (except phenylalanine) and further asparagine, glutamine, methionine and threonine. In six normal subjects the same infusion reduced significantly (P less than 0.05 to 0.001) plasma alanine, asparagine, glutamate, glutamine, glycine, proline, serine, threonine, arginine, ornithine, lysine and tyrosine. However, the effect was significantly (P less than 0.01 or 0.001) less marked for alanine, glutamine, glycine, methionine, serine, threonine and arginine. This particular glucagon sensitivity of duodenopancreatectomized patients suggests that glucagon deficiency is the cause of their hyperaminacidaemia. By contrast, lipoprotein concentrations were virtually unaffected by either glucagon deficiency or its replacement. In the light of the marked hypoaminacidaemia in glucagonoma patients these results attribute to glucagon a major role as a regulator of protein metabolism.  相似文献   
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