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Shankar EM Kumarasamy N Vignesh R Balakrishnan P Solomon SS Murugavel KG Saravanan S Velu V Farooq SM Hayath K Muthu S Solomon S Rao UA 《Japanese journal of infectious diseases》2007,60(6):337-341
The prevalence of Mycoplasma pneumoniae among HIV-positive patients with community-acquired pneumonia (CAP) remains unclear. We investigated 300 HIV-positive adults (200 with CAP and 100 with no respiratory illness) and 75 HIV-negative adults with CAP for the prevalence of respiratory pathogens using culture and serology. A growth inhibition test was employed to confirm the isolates of M. pneumoniae using species-specific typing sera. The prevalence of M. pneumoniae in HIV-positive subjects was 17% by induced sputum and 11.3% by throat swab culture. The seroprevalence of anti-M. pneumoniae IgM was 11.7% by ELISA and 14.3% by the gelatin microparticle agglutination test. The prevalence of M. pneumoniae among HIV-negative cases was relatively low. Streptococcus pneumoniae was predominant (28%) among subjects with lower respiratory disease, whereas Staphylococcus aureus (15%) was common among upper respiratory symptomatic cases. Rales (P=0.001), pharyngeal erythema (P=0.02), cervical adenopathy (P=0.004), skin rash (P=0.001), and crepitations (P=0.001) were each significantly related to M. pneumoniae positivity. Statistical significance was observed in relation to total lymphocyte count (P=0.02) and erythrocyte sedimentation rate (P=0.04), as well as M. pneumoniae positivity. This study shows that the prevalence of M. pneumoniae in HIV-positive subjects is comparatively higher than in HIV-negative subjects with pulmonary symptoms, and concords with previous pilot studies carried out in Chennai, South India. 相似文献
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This study includes comparatively evaluating and drawing general conclusion about the best advisable taper and cement for maximal retention. Eighty extracted human maxillary premolar teeth with sound surfaces were selected using dial vernier caliper. Selected teeth were randomly divided into five different taper groups (0°, 3°, 6°, 9° and 12°). The crown preparations with different tapers respectively were achieved by graduated customized device. Preparations were verified with special set up. Crowns were cast with Co–Cr alloy; metal copings were luted with glass ionomer and zinc phosphate cement. Retention was measured (MPa) by separating the metal crowns from the teeth under tension on a universal testing machine, data was recorded and statistically analyzed. Glass ionomer cemented 0° and 12° taper group showed increase in retentive strength (p = 0.003 hs), when compared to zinc phosphate cement. 9° and 12° group showed decreased retentive strength (p = 0.001 vhs) when compared with 0° taper group. No significant difference found between 0° and 3° and 6° group. The choice of cement for crowns prepared within this ideal range (0°–6° taper) might be of limited clinical significance. 3° and 6° taper with zinc phosphate or glass ionomer cement shown to be ideal for maximum retention. 相似文献
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Most supernumerary impacted teeth are located in the anterior maxillary region. They are classified according to their form and location. Their presence may give rise to a variety of clinical problems. The detection of supernumerary teeth is best achieved by thorough clinical and radiographic examination. Their management should form part of a comprehensive treatment plan. This article presents an overview of the diagnostic problems associated with multiple supernumerary impacted teeth and includes a discussion of the classification, diagnosis, and management of this difficult clinical entity. 相似文献
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Reichenbach S Guermazi A Niu J Neogi T Hunter DJ Roemer FW McLennan CE Hernandez-Molina G Felson DT 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2008,16(9):1005-1010
OBJECTIVES: Bone attrition probably constitutes remodeling of the bone, resulting in flattening or depression of the articular surfaces. Defining bone attrition is challenging because it is an accentuation of the normal curvature of the tibial plateaus. We aimed to define bone attrition on magnetic resonance imaging (MRI) of the knee using information from both radiographs and MRIs, and to assess whether bone attrition is common prior to end stage disease osteoarthritis (OA) in the tibio-femoral joint. METHODS: All knees of participants in the community-based sample of the Framingham OA Study were evaluated for bone attrition in radiographs and MRIs. Radiographs were scored based on templates designed to outline the normal contours of the tibio-femoral joint. MRIs were analyzed using the semi-quantitative Whole-Organ Magnetic Resonance Imaging Scoring (WORMS) method. The prevalence of bone attrition was calculated using two different thresholds for MRI scores. RESULTS: Inter-observer agreement for identification of bone attrition was substantial for the radiographs (kappa=0.71, 95% CI 0.67-0.81) and moderate for MRI (kappa=0.56, 95% CI 0.40-0.72). Of 964 knees, 5.7% of the radiographs showed bone attrition. Of these, 91% of MRIs were also read as showing bone attrition. We selected a conservative threshold for bone attrition on MRI scoring (>/=2 on a 0-3 scale) based on agreement with attrition on the radiograph or when bone attrition on MRI co-occurred with cartilage loss on OA. Using this threshold for bone attrition on MRI, bone attrition was common in knees with OA. For example, in knees with mild OA but no joint space narrowing, 13 of 88 MRIs (14.8%) showed bone attrition. CONCLUSIONS: Using MRI we found that many knees with mild OA without joint narrowing on radiographs had bone attrition, even using conservative definitions. The validity of our definition of bone attrition should be evaluated in further studies. Bone attrition may occur in milder OA and at earlier stages of disease than previously thought. 相似文献