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51.
Background: Pulmonary vein isolation (PVI) as a treatment for atrial fibrillation (AF) is commonly performed. This procedure can damage the esophagus. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) offers noninvasive assessment of scar. We sought to examine the prevalence of esophageal hyperenhancement on LGE‐CMR prior to and following PVI. Methods: Seventy‐four patients underwent LGE‐CMR prior to and 1.7 ± 1.9 months post PVI for AF. Transmural esophageal hyperenhancement was visually assessed. The pre‐ and post PVI esophageal position was measured, relative to the vertebral body. Results: Prior to PVI, 3% (2/74) of patients had esophageal LGE on CMR. At post‐PVI follow‐up, 30% (23/74) of the studies demonstrated new esophageal hyperenhancement adjacent to an ablation site. Most (74%, 17/27) positive esophageal LGE studies were performed >30 days after PVI, while no (0/9) studies performed >2 months post PVI were positive for esophageal hyperenhancement. The presence of post‐procedural esophageal hyperenhancement was not associated with longer ablation time (P = 0.42), use of an irrigated catheter (74% with LGE vs 47% without, P = 0.16), right‐sided esophageal location (56% with LGE vs 39% without, P = 0.17), size of left atrium cavity (58 ± 8 mm with LGE vs 61 ± 10 mm without, P = 0.15), or the timing of the LGE‐CMR study after PVI (36 ± 10 days with LGE vs 60 ± 66 days without, P = 0.09). Conclusion: Though rare before PVI, new esophageal LGE is seen in almost one‐third of patients after PVI. The clinical implications to remain to be explored, but clinicians should be aware of this frequent imaging finding. (PACE 2010; 33:661–666)  相似文献   
52.
Dubin-Johnson综合征是一种先天性非溶血性黄疸,在临床中较罕见,需与其他原因所导致的黄疸相鉴别.本文报告了我院1例Dubin- Johnson综合征的诊治情况,有助于加深对该病的认识.  相似文献   
53.
54.
A postal survey of recently appointed consultant paediatricians was undertaken to determine whether they perceived their training had adequately equipped them for their current job. The response rate was 69% (207/299). After excluding replies from consultants trained outside the UK the analysis was carried out on 167 replies. Trainees held a mean 5.2 posts during general and higher professional training, necessitating a mean 1.8 house moves. Altogether 82% felt moves were beneficial to training but 46% found moves 'very disruptive' to family life. Only 12% of district general hospital and 22% of teaching hospital senior registrars took two research sessions a week. Supervision and training in research was absent or poor for more than 60%; 24% felt major changes and 55% moderate changes were needed to current training. Training in non-clinical skills was particularly in demand and a curriculum for both trainers and trainees with regular appraisals is required. Research at senior registrar level needs review and educational methods improved to achieve better training in a shorter period.  相似文献   
55.
Although the elective induction of cardiac arrest for implantable defibrillator insertion under general anesthesia is widely used, the hemodynamics of recovery of arterial blood pressure after cardiac arrest is not well-defined. Accordingly, the time course of recovery of systolic arterial pressure was studied in seven patients during the repetitive induction of ventricular fibrillation (n = 6) or ventricular flutter (n = 1). The mean number of episodes of cardiac arrest was 7 ± 2, and the mean drop in systolic pressure was 84 ± 16mmHg. The mean recovery time for systolic pressure was 10 ± 6 seconds, the average systolic pressure recovery rate was 13 ± 14 mmHg/sec, and the mean percent systolic pressure recovery was 94%± 9%. A negative logarithmic relation was found to exist between the rate of systolic arterial pressure recovery and the duration of ventricular fibrillation or flutter with a correlation coefficient of 0.68 to 0.97 (P < 0.05) in five of the seven patients. A linear relation between the time for systolic pressure recovery and duration of asystole was also defined. These results are consistent with the view that prolongation of ventricular fibrillation or flutter increases the duration of arterial pressure recovery through a negative effect on left ventricular contractility. Increased understanding of these relations may lead to increased safety of implantable defibrillator insertion.  相似文献   
56.
Atopy is associated with diminished cell-mediated immunity and increased amounts of IgE, both of which may be caused by imbalances of T lymphocyte subsets. We compared the composition of highly purified peripheral-blood T cells of fifteen atopic asthmatics with ten non-atopic control subjects. Each subject was examined on five separate occasions. Indirect immunofluorescence using monoclonal antibodies was used to define T cell subsets. We examined the proportion of T cells with T3 (most T cells), T4 (helper/inducer), T8 (suppressor/cytotoxic), M1 (natural killer), and Ia (activated T cells) surface antigens. Blood was obtained at the same time of day to eliminate the effects of circadian rhythm. Subjects were taking no medications. We found no difference between the groups of the percentage of T cells with T4, T8, M1, and Ia antigens, nor the ratio of T4+ (helper) to T8+ (suppressor) cells. T3 percent was slightly (94.3 vs 92.5%) higher in the atopic group. We conclude that atopic asthma is not associated with imbalances of peripheral-blood T cell subsets.  相似文献   
57.
58.
The optimum experimental conditions have been investigated for the measurement of the birth-rate in human psoriatic epidermis using the vinca alkaloids vinblastine and vincristine. The dose response characteristics of the two drugs were assessed over a 2.5 h collection period; although the dose response characteristics differed between the two agents, a dose of 1μg injected intradermally was considered to be optimal for both. The linearity of metaphase correction was assessed for both agents, taking biopsies for up to 10 h after injection. It was found that there was a delay period for up to an hour which must be avoided during the analysis to prevent an underestimate of the birth rate. However, linearity was then demonstrated for up to 4 h after injection. Metaphase degeneration was assessed by isolating a cohort of unlabelled cells in the G2 phase and tracing their fate over the next 10 h. It was found that the minimum life of an arrested metaphase was of the order of 4 h, and then metaphases degenerated at the rate of approximately 0.4% per hour. It is recommended that metaphase arrest experiments in psoriatic epidermis be confined to 4 h although, if required, correction factors are available to correct for experiments which are lengthened. Finally it is shown that flux into DNA synthesis exceeds the flux into mitosis by four or five times; several explanations are considered, and it is thought that the most likely explanation involves the death of psoriatic cells in the G2 phase.  相似文献   
59.
Impairment in Pulmonary Bioenergetics Following ChlorphentermineAdministration to Rats. Zychlinski, Lech, Montgomery, Mark R.,Shamblin, Patricia B., and Reasor, Mark J. (1983). Fundam. Appl.Toxicol. 3:192-198. Biochemical alteration in pulmonary oxidativemetabolism and morphological integrity of lung mitochondriawere examined in rats following administration of chlorphentermine(30 mg/kg, ip, 5 days per week) for 1 or 2 weeks. During thefirst week of treatment, body weight gain and food intake weredecreased markedly but returned to control levels during thesecond week. Phospholipid content of the lung was increased31% and 110% after 1 and 2 weeks of treatment, respectively.This was accompanied by a striking intraalveo-lar accumulationof hypertrophic alveolar macrophages. The metabolism of both(1-14C)- and (6-14C)-glucose was decreased 27% and 26%, respectively,after 2 weeks of drug treatment. In rat lung mitochondria, chlorphenterminesignificantly lowered the RCR and ADP/O ratio and stimulatedstate 4 respiration. State 3 respiration and uncoupled staterespiration were unaffected. These data indicate that chlorphenterminefunctions as a true uncoupler of oxidative phosphorylation whenadministered in vivo. Furthermore, disruption of mitochondrialmembranes was observed frequently in lung mitochondria fromtreated animals. These combined data indicate that the inductionof pulmonary phospholipidosis by chlorphentermine is accompaniedby marked alterations in subcellular bioenergetics and mito-chondrialstructure.  相似文献   
60.
RECTAL PROLAPSE     
One hundred and twenty-seven patients with complete rectal prolapse have been reviewed. The condition occurred more commonly in females than males (105 to 22), and at an older age in females (mean age 55 years compared with 40 years for males). Although the diagnosis is usually obvious, the importance of recognizing occult prolapse is stressed, especially in association with benign rectal ulcer, localized proctitis and colitis cystica profunda. Examination of the patient in the squatting position may assist in showing occult prolapse. Associated incontinence occurred in 33 patients (26%). Since 1971 the policy of this Unit has been to perform a Ripstein repair for complete rectal prolapse wherever possible. One hundred and two Ripstein repairs have now been performed. A minimum follow-up period of two years is available for 53 patients, of whom 50 (94%) have had their prolapse cured. Control of prolapse usually improves continence; however, seven (13%) remained incontinent despite surgery. The Ripstein. repair is strongly advocated as the most effective operation for cure of complete rectal prolapse.  相似文献   
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