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71.
Dens invaginatus (DI) often causes dysmorphic changes in both the crown and root. This case report presents a complicated type 3a DI in a maxillary lateral incisor with labial talon cusp and root bifurcation. Although lingual talon cusp is common in maxillary lateral incisor, labial talon cusp is rare. An auxiliary palatal root in maxillary lateral incisor is also unusual. No such case involving all three variations has been described in the literature. The DI was classified as type B4 according to Schulze and Brand, as it involved division of pulp and root. DI was managed by orthograde MTA, radisectomy and periodontal regeneration was done for the palatal root. Labial talon associated with DI and can lead to early periodontal/pulpal involvement. Type 3 DI can affect the root with marked dilatation and division. Additional palatal root should be carefully detected in type 3a DI and managed with the aid of CBCT.  相似文献   
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The Ilizarov method has been studied extensively in the management of non-union of long bones. In most cases this involves filling of defects present primarily or after débridement by bone transport. Acute docking over gaps longer than 2 cm has not been adequately studied, however. The purpose of this paper is to report the efficacy of acute peg in hole docking as a bone graft-sparing modality in the management of infected non-union of long bones.  相似文献   
74.
The current study aimed to exploit the electrostatic associative interaction between carrageenan and gelatin to optimise a formulation of lyophilised orally disintegrating tablets (ODTs) suitable for multiparticulate delivery. A central composite face centred (CCF) design was applied to study the influence of formulation variables (gelatin, carrageenan and alanine concentrations) on the crucial responses of the formulation (disintegration time, hardness, viscosity and pH). The disintegration time and viscosity were controlled by the associative interaction between gelatin and carrageenan upon hydration which forms a strong complex that increases the viscosity of the stock solution and forms tablet with higher resistant to disintegration in aqueous medium. Therefore, the levels of carrageenan, gelatin and their interaction in the formulation were the significant factors. In terms of hardness, increasing gelatin and alanine concentration was the most effective way to improve tablet hardness. Accordingly, optimum concentrations of these excipients were needed to find the best balance that fulfilled all formulation requirements. The revised model showed high degree of predictability and optimisation reliability and therefore was successful in developing an ODT formulation with optimised properties that were able deliver enteric coated multiparticulates of omeprazole without compromising their functionality.  相似文献   
75.
Mitomycin C (MMC) is an antineoplastic agent used to fight a number of different cancers including cancer of the stomach, colon, rectum, pancreas, breast, lung, uterus, cervix, bladder, head, neck, eye and oesophagus. It is a potent DNA cross-linker. The prolonged use of the drug may result in permanent bone marrow damage and other various types of secondary tumors in normal cells. The toxic effect of anticancerous drugs may be reduced if supplemented with natural antioxidants/plant products. With this view, the effect of 5, 10 and 15 μM of curcumin was studied against the genotoxic doses of MMC, i.e. 10 and 20 μM, in cultured human lymphocytes using cell viability, lipid peroxidation and DNA damage quantification as parameters. The treatment of curcumin with MMC results in a significant dose-dependent increase in cell viability and decrease in lipid peroxidation and DNA damage suggesting a protective role of curcumin against the anticancerous drug mitomycin C.  相似文献   
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Use of a very low probability interpretation of ventilation/perfusion (V/Q) lung scans, if verified by prospective evaluation to have a low positive predictive value (PPV), will reduce the number of nondiagnostic interpretations of V/Q scans and may be particularly useful in patients with a relative contraindication to CT. The purpose of this investigation was to test the hypothesis that a very low probability interpretation of the V/Q scan has a PPV of <10%. METHODS: Data are from PIOPED II (Prospective Investigation of Pulmonary Embolism Diagnosis II). Very low probability criteria are (a) nonsegmental perfusion abnormalities, (b) perfusion defect smaller than corresponding radiographic lesion, (c) > or =2 matched V/Q defects with regionally normal chest radiograph, (d) 1-3 small segmental perfusion defects (<25% of a segment), (e) solitary triple matched defect in middle or upper lung zones, (f) stripe sign around the perfusion defect(s), and (g) perfusion defect from pleural effusion equal to one third or more of the pleural cavity with no other perfusion defect. RESULTS: A very low probability consensus interpretation of the V/Q scan was made in 56% of patients. The PPV of a very low probability interpretation of the V/Q scans was 36 of 440 patients (8.2%). Among patients with suspected pulmonary embolism who had a low clinical probability objective clinical assessment and a very low probability V/Q scan, the PPV was 8 of 259 patients (3.1%). Among women < or =40 y, the PPV of the very low probability V/Q with a low objective clinical assessment was 1 of 50 (2%). CONCLUSION: The very low probability V/Q scan together with a low probability clinical assessment reliably excludes pulmonary embolism.  相似文献   
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OBJECTIVE: Name-based classification systems are potentially useful in identifying study samples based on probable ethnic minority group. The aim of the current study was to assess the validity of the Nam Pehchan name classification programme of religion and language against subject self-report. STUDY DESIGN AND SETTING: A population-based cross-sectional survey conducted in areas of the North-West and West Midland regions of England with a relatively high density of South Asian ethnic minority groups. The sampling frame was age-sex registers of selected general practices and subjects were classified according to language and religion using the Nam Pehchan programme. These were compared with responses by subjects on a self-complete postal questionnaire. RESULTS: One thousand nine hundred and forty-nine subjects who participated, classified themselves as South Asian. Sensitivity in identifying religion was high amongst Muslims (92%) and Sikhs (86%), and somewhat lower in Hindus (62%). Specificity exceeded 95% for all ethnic groups. The vast majority of subjects assigned Punjabi or Gujarati as their main South Asian language indicated that they did in fact speak these languages (97% and 94%, respectively). Subjects assigned Urdu or Bengali, however, were less likely to do so (61% and 35%, respectively). CONCLUSIONS: The name-based classification system Nam Pehchan has demonstrated high levels of accuracy in some sub-groups of the South Asian population in determining subjects likely language spoken and religion-and is likely to be a useful additional tool when information on ethnicity is not already available.  相似文献   
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