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1.
Treatment for inflammation of the tonsils has taken a variety of therapeutic forms over the years, ranging from the application of iodine and massage in the preantibiotic era to the tonsillectomy, which prevails today. The architecture of the cryptic tonsil, its clinical implications, and the rationale for a conservative, yet effective treatment modality focusing on the tonsillar crypts are addressed in this article. Also described are the procedures and results of a retrospective clinical study in which conventional tonsillectomy was compared with CO2 SwiftLase cryptolysis. Although our observations are not based on a prospective, controlled study, the information disseminated here may be useful to otolaryngologists who routinely perform tonsillectomy in their practice, using conventional surgical dissection methods or the CO2 laser. According to our experience with a population of 120 patients, cryptolysis offers some clear advantages, particularly when performed with the SwiftLase apparatus. The procedure can be performed safely in an ambulatory surgery or office setting under local anesthesia. The cooperative patient avoids the cost and risks of general anesthesia. Limited tissue destruction significantly reduces operative and postoperative complications, discomfort, and recovery time. To conclude, CO2 SwiftLase cryptolysis is a safe and cost-effective method of treating tonsil pathology without unnecessary sacrifice of the organ, and undue risks and expenses to the patient.11,12  相似文献   
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Preduodenal mechanisms in initiating gallbladder emptying in man   总被引:2,自引:0,他引:2  
The existence of preduodenal phases of gallbladder emptying in normal volunteers was investigated by evaluating the effect of sham feeding a sandwich (chew and spit) (n = 15), the sight and smell of food followed by sham feeding a cooked meal (n = 15), and gastric distension (intragastric balloon tube) (n = 9) on gallbladder emptying and comparing these responses with those after ingestion of a standard meal (n = 14). A control group given no intestinal stimuli were studied to determine the frequency of spontaneous emptying during fasting (n = 18). 99mTc-EHIDA (2,6 diethylphenylcarbamoylmethyliminodiacetic acid) was used as the biliary tracer. The frequency of gallbladder emptying during fasting was 0.0045/min. Thus, in any 20 min period emptying occurred spontaneously in only about 1 in 11 volunteers. Significant emptying (greater than 5 per cent over 20 min) occurred in 8 out of 15 volunteers after sham feeding a sandwich (P less than 0.001 versus control), in 8 out of 15 volunteers after sham feeding a cooked meal (P = 1.0 versus sandwich sham feed, n.s.), in 6 out of 9 volunteers after gastric distension (P less than 0.001 versus control) and in 14 out of 14 volunteers after meal ingestion. The rate of emptying was significantly greater in the gastric distension and meal ingestion groups compared with other groups (P less than 0.05). However, the emptying rate after sham feeding was not significantly different from spontaneous gallbladder emptying (P greater than 0.05, n.s.). There was no significant difference in time to onset of emptying between the four stimulus groups (P greater than 0.05, n.s.). These results suggest that pre-duodenal stimuli can evoke gallbladder emptying in man, although the precise physiological significance of this phenomenon remains to be established.  相似文献   
3.
BACKGROUND: The clinical significance of conduction recurrences in isolated pulmonary veins of patients with atrial fibrillation is not established. METHODS: Twenty-two patients with paoxysmal atrial fibrillation underwent successful pulmonary vein isolation. Six months after the procedure, 14 patients were free of atrial fibrillation. Two of these patients were subjected to repeat mapping of the left superior pulmonary vein. RESULTS: There was recurrence of pulmonary vein to left atrium conduction despite complete lack of symptoms or evidence of recurrent atrial fibrillation. CONCLUSION: Successful pulmonary vein isolation with abolition of paroxysmal atrial fibrillation does not confer permanent disconnection of the pulmonary vein musculature from the left atrium.  相似文献   
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Defective potassium currents in ataxia telangiectasia fibroblasts   总被引:1,自引:0,他引:1       下载免费PDF全文
Similarities exist between the progressive cerebellar ataxia in ataxia telangiectasia (AT) patients and a number of neurodegenerative diseases in both mouse and man involving specific mutations in ion channels and/or ion channel activity. These relationships led us to investigate the possibility of defective ion channel activity in AT cells. We examined changes in the membrane potential of AT fibroblasts in response to extracellular cation addition and found that the ability of AT fibroblasts to depolarize in response to increasing concentrations of extracellular K+ is significantly reduced when compared with control fibroblasts. Electrophysiological measurements performed with a number of AT cell lines, as well as two matched sets of primary AT fibroblast cultures, reveal that outward rectifier K+ currents are largely absent in AT fibroblasts in comparison with control cells. These K+ current defects can be corrected in AT fibroblasts transfected with the full-length ATM cDNA. These data implicate, for the first time, a role for ATM in the regulation of K+ channel activity and membrane potential.  相似文献   
6.
Ataxia-telangiectasia (A-T) is an autosomal recessive disorderinvolving cerebellar degeneration, immunodeficiency, radiationsensitivity, and cancer predisposition. A-T heterozygotes aremoderately cancer prone. The A-T gene, designated ATM, was recentlyidentified in our laboratory by positional cloning, and a partialcDNA clone was found to encode a polypeptide with a PI-3 kinasedomain. We report here the molecular cloning of a cDNA contigspanning the complete open reading frame of the ATM gene. Thepredicted protein of 3056 amino acids shows significant sequencesimilarities to several large proteins in yeast, Drosophilaand mammals, all of which share the PI-3 kinase domain. Manyof these proteins are involved in the detection of DNA damageand the control of cell cycle progression. Mutations in theirgenes confer a variety of phenotypes with features similar tothose observed in human A-T cells. The complete sequence ofthe ATM gene product provides useful clues to the function ofthis protein, and furthers understanding of the pleiotropicnature of the A-T mutations.  相似文献   
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As aesthetic surgeons we should look more closely at our finished products. A visible scar, distorted ear lobe or tragus, or unnatural hairline says "face lift" to a patient's friends and creates a self-conscious, unhappy patient. The modifications I have adopted of accepted techniques give a more natural look and less conspicuous scarring. They avoid the most dreaded question a patient's associates may ask: "Have you had a face lift?" The text outlines the areas where tipoffs are most prevalent and makes suggestions to minimize them. It is impossible to do inconspicuous surgery all the time, but it is possible by careful observation to minimize visual tipoffs. An unnatural tragus or bad scar should be considered as severe a complication as nerve damage. We should use as proficient avoidance techniques for one as for the other.  相似文献   
10.
Skin fibroblast strains from patients with ataxia-telangiectasia(A-T) were recently reported to be hypersensitive to the antitumorantibiotic neocarzinostatin (NCS). In this study, the distinctintermediate degree of NCS sensitivity previously shown withtwo strains of A-T heterozygous fibroblasts was extended andconfirmed in an additional eight strains. A sensitivity baselinefor A-T heterozygous cells has thus been established and mayserve for the laboratory diagnosis of A-T heterozygotes, a cancer-pronepopulation. The response of A-T homozygous and heterozygouscells to NCS was further characterized by two molecular parameters,DNA repair synthesis and inhibition of DNA replication. Thepattern of dose response with regard to DNA repair synthesis,as assayed by the benzoylated naphthoylated DEAE cellulose chromatographymethod, was similar in normal, A-T homozygous and A-T heterozygouscells, although certain variability between strains was observedwith regard to the amount of repair incorporation. This findingcorrelates with a similar observation made with the same cellstrains following -irradiation. Inhibition of DNA synthesisfollowing NCS treatment was reduced in A-T homozygous cells,as compared to normal cells, but the "Inhibition resistant"component of DNA synthesis typically observed following treatmentwith low doses of X-rays or bleomycin was not observed withNCS. A-T heterozygous cells showed somewhat less inhibitionof DNA synthesis than normal cells following NCS treatment,although this difference was small and was not significant enoughto serve as an additional laboratory diagnostic aid. It is concludedthat the reduced inhibition of DNA synthesis, rather than reducedextent of DNA repair synthesis, correlates with the cellularhypersensitivity of A-T homozygous cells. This hypersensitivityseems to be observed primarily, if not exclusively, with DNAbreaking agents.  相似文献   
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