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We report the case of a patient with a 13-year history of pemphigus vulgaris (PV) treated with immunosuppressive agents, prednisone and mycophenolate mofetil who had developed lesions of Kaposi's sarcoma (KS) on a sole plaque of PV that had been previously treated with intralesional injections of steroids. The lesions were surgically removed and polymerase chain reaction (PCR) demonstrated human herpesvirus-8 (HHV-8) DNA. There were neither recurrences nor later dissemination of KS following gradual decrease of the immunosuppressive therapy. We suggest that the treatment with intralesional steroids may have influenced the local reactivation of a latent infection of the virus, determining the appearance of this localized KS.  相似文献   
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The aim of this study was to identify the strengths and weaknesses of five DNA fingerprint methods for epidemiological typing of Streptococcus pneumoniae. We investigated the usefulness of (i) ribotyping, (ii) BOX fingerprinting with the BOX repetitive sequence of S. pneumoniae as a DNA probe, (iii) PCR fingerprinting with a primer homologous to the enterobacterial repetitive intergenic consensus sequence, (iv) pulsed-field gel electrophoresis of large DNA fragments, and (v) restriction fragment end labeling to detect restriction fragment length polymorphism of small DNA fragments. Twenty-eight S. pneumoniae strains isolated from the blood and/or cerebrospinal fluid of 21 patients were analyzed. Genetic clustering among the 28 strains was independent of the DNA fingerprint technique used. However, the discriminatory power and the similarity values differed significantly among the individual techniques. BOX fingerprinting, pulsed-field gel electrophoresis, and restriction fragment end labeling provided the highest degree of discriminatory power. Furthermore, the ease with which computerized fingerprint analysis could be conducted also varied significantly among the techniques. Ribotyping, BOX fingerprinting, and restriction fragment end labeling were very suitable techniques for accurate computerized data analysis. Because of their high discriminatory potential and ease of accurate analysis, we conclude that BOX fingerprinting and restriction fragment end labeling are the most suitable techniques to type pneumococcal strains.  相似文献   
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A typing method for bacteria was developed and applied to several species, including Escherichia coli and Actinobacillus actinomycetemcomitans. Total genomic DNA was digested with a restriction endonuclease, and fragments were enabled with [alpha-32P]dATP by using the Klenow fragment of DNA polymerase and separated by electrophoresis in 6% polyacrylamide/8 M urea (sequencing gel). Depending on the restriction endonuclease and the bacterium, the method produced approximately 30-50 well-separated fragments in the size range of 100-400 nucleotides. For A. actinomycetemcomitans, all strains had bands in common. Nevertheless, many polymorphisms could be observed, and the 31 strains tested could be classified into 29 distinct types. Furthermore, serotype-specific fragments could be assigned for the three serotypes investigated. The method described is very sensitive, allowing more distinct types to be distinguished than other commonly used typing methods. When the method was applied to 10 other clinically relevant bacterial species, both species-specific bands and strain-specific bands were found. Isolates from different locations of one patient showed indistinguishable patterns. Computer-assisted analysis of the DNA fingerprints allowed the determination of similarity coefficients. It is concluded that genomic fingerprinting by restriction fragment end labeling (RFEL) is a powerful and generally applicable technique to type bacterial species.  相似文献   
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1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
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SUMMARY A young patient presenting with splenomegaly and hypersplenism was inadvertently found to have selective IgA deficiency. There were no symptoms of immunodeficiency and the patient responded well to splenectomy, with return of blood counts to normal without adverse effects. No other cause for the hypersplenism was found. We postulate selective IgA deficiency as a cause of splenomegaly and hypersplenism.  相似文献   
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In a retrospective study, which comprised the whole Dutch childhood population of approximately 3 million children, the authors assessed the influence of an isolated meningeal relapse, occurring as first relapse, together with some patient and treatment characteristics on prognosis in 142 children with acute lymphoblastic leukemia (ALL). Until their first relapse, patients were initially treated according to standard protocols, whereas the treatment for relapse was heterogeneous. Concerning the probability of achieving a second complete remission (CR) it appears that the duration of the first CR is the single most important prognostic factor. The duration of the first CR is also the most important factor with regard to the duration of the second CR, upon which also age and sex have a significant influence. Concerning the survival from the time of central nervous system (CNS) relapse, again the duration of the first CR appears to be the most important prognostic factor, followed by age and the institution of systemic reinduction treatment. Other factors, such as initial leukocyte count, attainment of first CR within 48 days, type of reinduction treatment, and the cerebral spinal fluid (CSF) blast count at the time of relapse, have a less important, but nevertheless significant influence on survival. The median survival from the time of CNS relapse is 25 months, the 5-year survival is 25%, whereas the ultimate survival will be less than 20%. From 90 patients who developed second or subsequent relapses, 75% experienced a bone marrow relapse during the follow-up period. From this study the authors conclude that CNS relapse in children with ALL carries a grave prognosis, which requires the institution of intensive retreatment programs.  相似文献   
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