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A patient with culture-negative endocarditis was diagnosed with Q fever endocarditis based on the results of serological tests and positive leukocyte cultures obtained using conventional viral cultures and the shell vial technique. This case report suggests that isolation ofCoxiella burnetii from blood may allow better diagnostic and therapeutical evaluation of patients with Q fever endocarditis. The use of both conventional and shell vial viral cultures is recommended for the isolation ofCoxiella burnetii from the blood of patients with apparently culture-negative endocarditis.  相似文献   
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The objective of this study was to validate the Spanish version of the Othmer and DeSouza Screening Test for Somatization Disorder. We have designed a validity study using the Standardized Polyvalent Psychiatric Interview, an instrument specifically designed to diagnose psychiatric morbidity in medical settings as the ‘golden rule’. The control group displayed ‘functional’ and ‘presenting’ somatization. The Othmer and DeSouza Screening Test, with a threshold of three symptoms, shows 88% sensitivity, 78% specificity and a misclassification rate of 17%. It is concluded that Othmer and DeSouza's screening test, with a threshold of three symptoms, is a useful tool for the diagnosis of somatization disorder in medical and primary care settings in Spain. Discrepancies with US findings are discussed on a cross-cultural basis.  相似文献   
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Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details.  相似文献   
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OBJECTIVES: The object of this study was to investigate the diversity among streptococcal species isolated from root canals in conjunction with endodontic therapy and to characterize their production of extracellular proteins. STUDY DESIGN: Consecutive root canal samples (RCS) taken as bacteriological controls during root canal treatment of teeth with apical periodontitis were analyzed in a total of 100 clinical cases. Bacteria were isolated and classified by selective media and gas liquid chromatography. Streptococcal strains were identified by carbohydrate fermentation, hydrolysis of aesculin/arginine, and production of enzymes. Releases of extracellular proteins by streptococci and Enterococcus spp in fluid culture media were examined with SDS-PAGE and 2-dimension gel electrophoresis (2 DE). Extracellular proteins produced were quantified and qualitatively analyzed. Specific proteins were targeted with Western immunoblot assays. Comparisons were made with type strains. RESULTS: Of a total of 241 bacterial strains recovered in the first samples submitted, Streptococcus gordonii, S anginosus, and S oralis were the most frequently isolated streptococci. In 49 of 89 resubmitted samples showing bacterial growth, S gordonii and S oralis still predominated among streptococci. Other common bacterial isolates were Enterococcus spp, Lactobacillus paracasei, and Olsenella uli. Quantitative and qualitative differences in extracellular protein production were observed among clinical isolates and laboratory streptococcal strains. In similar conditions for growth, S intermedius, S anginosus, S oralis, and S gordonii were strong producers of extracellular proteins (>3.0 microg/mL), while Enterococcus spp and S mutans were weak. Whole cell protein extracts showed a different profile from that of extracellular proteins. The chaperone protein DnaK was recognized to be produced extracellularly by S gordonii, S oralis, S anginosus, and S parasanguis. CONCLUSIONS: Being strong producers of extracellular proteins and by virtue of common presence in teeth undergoing endodontic therapy, S gordonii, S anginosus, and S oralis may be of pathogenic significance in posttreatment apical periodontitis.  相似文献   
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Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended. However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens, Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.   相似文献   
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A new approach to modeling the signal observed in arterial spin labeling (ASL) experiments during changing perfusion conditions is presented in this article. The new model uses numerical methods to extend first-order kinetic principles to include the changes in arrival time of the arterial tag that occur during neuronal activation. Estimation of the perfusion function from the ASL signal using this model is also demonstrated. The estimation algorithm uses a roughness penalty as well as prior information. The approach is demonstrated in numerical simulations and human experiments. The approach presented here is particularly suitable for fast ASL acquisition schemes, such as turbo continuous ASL (Turbo-CASL), which allows subtraction pairs to be acquired in less than 3 s but is sensitive to arrival time changes. This modeling approach can also be extended to other acquisition schemes.  相似文献   
120.
Summary Genes involved in cancer generation are usually tumor suppressors and oncogenes. Progressive genetic alterations in these genes are involved in the mechanisms of tumorigenesis. In prostate cancer, additionally several chromosomal loci that should harbor mutated genes have been proposed. Some genes have been found altered in prostate cancer, such as PTEN, TP53, AR, RNASEL (HPC1), ELAC2 (HPC2), CDKN2A and MSR1 and those can be natural targets for new strategies of treatment. Besides, gene therapy has been suggested to be suitable for prostate cancer treatment. This approach includesex vivo corrective therapy, suicide, and antisense therapy.  相似文献   
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