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991.
The aim of this study was to evaluate the microbiota and surface of failed titanium dental implants from 4 manufacturers. Twelve mobile dental implants were retrieved from 10 smokers after 3 to 10 years of functional loading. Before implant removal, microbial samples were taken and evaluated using polymerase chain reaction. After implant removal, analyses of the failed implant surfaces were performed using scanning electron microscopy and energy-dispersive spectrometer x-ray. Periodontal pathogens such as Aggregactibacter actinomycetemcomitans, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola were detected in all implants in different proportions. Surface analysis showed varying degrees of surface roughness between the samples and the presence of proteinaceous material, appearing mainly as dark stains. Foreign carbon, oxygen, sodium, calcium, aluminum, and silicon elements were also found. Although no material-related causes of implant failure were detected, several periodontal pathogens were identified independently of the surface topography or manufacturer.  相似文献   
992.
A 29-year-old woman with no history of heart disease was admitted for the treatment of congestive heart failure. Six months earlier, she had given birth, then 20 days later developed a fever and cardiac failure ensued. An echocardiogram demonstrated severe mitral valve regurgitation. Her blood cultures were positive, and we made a diagnosis of mitral valve regurgitation due to infectious endocarditis. Despite treatment for congestive heart failure and antibiotic therapy, resulting in negative blood cultures, her congestive heart failure did not improve, and vegetation on the mitral valve was observed by echocardiography. We successfully removed the infected tissue with mitral valve plasty.  相似文献   
993.
The use of buffered neutral liquid ammonia medium for the first time provided evidence for a current doubling effect on p-InP during oxygen photoreduction. Unlike results in aqueous medium, a common mechanism of O2 reduction was observed at p-InP and p-GaAs electrodes. When protons were added to the solution, two different oxygen reduction mechanisms occurred at these electrodes. This study emphasizes the important results of the hydrogenated p-InP surface and revealed that liquid ammonia (at 223 K) was perfectly appropriate to understand the mechanism of O2 reduction at InP electrodes.  相似文献   
994.
995.
Grebe‐Quelce‐Salgado chondrodystrophy is an autosomal recessive non‐lethal skeletal dysplasia. Affected individuals have normal head, neck, and trunk skeleton, relatively normal humeri and femora, short and deformed radii, ulnae, tibiae, and fibulae, and severe abnormalities of hands and feet. Polydactyly is frequent. Digits present as globular appendages and are characteristic of the condition. The disease is caused by a missense mutation in the gene encoding cartilage‐derived morphogenetic protein‐1 (CDMP‐1). Most cases described in the literature are from Brazil and, among these, all had ancestors from a particular region in the state of Bahia. We describe two cases of Grebe‐Quelce‐Salgado chondrodystrophy visualized by prenatal ultrasound. The patients presented in this report do not descend from the population of Bahia and, to our knowledge, case two is the only case with prenatal clinical diagnosis in a family with no previously affected children. © 2002 Wiley‐Liss, Inc.  相似文献   
996.
Regular physical exercise is responsible for various health benefits, and is recommended for primary and secondary cardiovascular (CV) prevention. Despite these recognized benefits, various clinical events can occur in athletes, including acute myocardial infarction and sudden cardiac death (SCD); the main cause of SCD in veteran athletes is coronary artery disease (CAD). The relationship between intense exercise training and CAD is controversial, and a U-shaped association has been hypothesized. If this is the case, screening for subclinical CAD in older athletes may be justified, and various different methodologies have been proposed. However, the methodology for screening veteran athletes is not consensual, and several markers of CAD, in addition to clinical CV risk factors, could improve risk stratification in this population. In the present paper we review the published data on CAD in athletes, focusing on the relationship between the dose of exercise and CAD, as well as the implications for pre-participation screening of veteran athletes.  相似文献   
997.
998.
Background and study aims: Available scoring systems to assess the risk for major bleeding in patients on chronic anticoagulation seem inadequate in predicting higher diagnostic yields of small bowel capsule endoscopy (SBCE) or higher rebleeding rates in patients with suspected small bowel bleeding. The aim of this study was to evaluate the ability of the new ORBIT score in predicting positive findings of SBCE or higher rebleeding rates in chronically anticoagulated patients with suspected small bowel bleeding.

Patients and methods: Retrospective analysis of 570 patients who consecutively underwent SBCE for the study of suspected small bowel bleeding. For each of the 67 patients who were on chronic anticoagulation, ORBIT score (Older age, Reduced hemoglobin/hematocrit, Bleeding history, Insufficient kidney function and Treatment with antiplatelets) was calculated. Patients were classified as high-risk (ORBIT score?≥4) or low/intermediate-risk (ORBIT score?<4). Data on SBCE findings, diagnostic yield and rebleeding were compared between groups.

Results: When ORBIT score was calculated, 41 and 26 patients were classified as low/intermediate-risk and high-risk, respectively. When low/intermediate-risk and high-risk groups were compared, no differences were found in the diagnostic yield of SBCE (39.0% vs. 23.1%; p?=?.176). However, in high-risk patients, rebleeding was significantly more common than in low/intermediate-risk patients (80.0% vs. 36.6%; p?=?.003).

Conclusions: In patients presenting with suspected small bowel bleeding and on chronic anticoagulation, the new ORBIT score seems promising in identifying those with a higher risk of rebleeding, in whom a closer follow-up and a more aggressive diagnostic and therapeutic strategy is advisable.  相似文献   
999.
1000.
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