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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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We describe acquired immune deficiency manifested by opportunistic infections in 10 previously healthy heterosexual Haitian men. The opportunistic pathogens included Toxoplasma gondii (in four patients), Cryptococcus neoformans (in one), Pneumocystis carinii (in four patients), and Candida albicans (in three). Six of the patients also had Mycobacterium tuberculosis. Immunologic studies of three patients showed a decrease in the numbers and activity of helper T cells, with normal or increased populations of suppressor T cells. Serologic markers for previous infections from hepatitis A, cytomegalovirus, and herpes simplex virus were detected in several patients. Six of the patients died despite specific antimicrobial therapy. The clinical and immunologic findings in these 10 Haitians are similar to those reported in drug addicts and homosexuals with the acquired immune-deficiency syndrome.  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   
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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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Using a sample of 678 HIV-seronegative women, we measured self-reports of HIV-related cognitions, specifically knowledge, perceived exposure risks, and outcome expectations. We also ascertained prevalent and incident bacterial STDs and measured self-reports of behavioral risk reductions. We tested for associations between (a) cognitions and STD prevalence, (b) cognitions and incident STDs, (c) cognitions and behavioral risk reductions, and (d) risk reductions and incident STDs. Symptom knowledge was associated with lower prevalence, but not incidence. Beliefs in the efficacy of risk reductions showed a protective effect against incident STDs. Perceived exposure risk and symptom knowledge were associated with risk reduction behavior.  相似文献   
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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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