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BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB), defined as resistance to at least isoniazid (INH) and rifampicin (RMP), is considered a threat to TB control. Implementation of DOTS ensures high cure rates and prevents MDR. OBJECTIVE: To study the prevalence of MDR-TB from a retrospective analysis of the data in a tuberculosis unit where DOTS was implemented over a period of 6 years through public private mix (PPM). METHODS: Drug susceptibility testing of Mycobacterium tuberculosis samples isolated from the cultures of newly registered and retreatment sputum smear-positive cases during 2001-2003. RESULTS: During the study, 909 sputum-positive cases were registered and analysed. Of these, 714 were new and 195 were retreatment sputum-positive cases. INH resistance was found in 3.2% (23) of new and 9.2% (18) of retreatment cases. RMP resistance was present in 1.5% (11) of new and 7.2% (14) of retreatment cases. MDR was present only in 0.14% (1) of new and 2% (4) of retreatment cases. New cases had cure rates of 96% compared to 85% in retreatment cases. CONCLUSION: The prevalence of MDR-TB is low where success rates are high.  相似文献   
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Background

Magnetic resonance imaging (MRI) is considered the imaging standard for diagnosis and characterization of perianal complications associated with Crohn disease in children and adults.

Objective

To define MRI criteria that could act as potential predictors of treatment response in fistulizing Crohn disease in children, in order to guide more informed study interpretation.

Materials and methods

We performed a retrospective database query to identify all children and young adults with Crohn disease who underwent serial MRI studies for assessment of perianal symptoms between 2003 and 2010. We examined imaging features of perianal disease including fistula number, type and length, presence and size of associated abscess, and disease response/progression on follow-up MRI. We reviewed imaging studies and electronic medical records. Statistical analysis, including logistic regression, was performed to associate MR imaging features with treatment response and disease progression.

Results

We included 36 patients (22 male, 14 female; age range 8–21 years). Of these, 32 had a second MRI exam and 4 had clinical evidence of complete response, obviating the need for repeat imaging. Of the parameters analyzed, presence of abscess, type of fistula according to the Parks classification, and multiplicity were not predictors of treatment outcome. Maximum length of the dominant fistula and aggregate fistula length in the case of multiple fistulae were the best predictors of treatment outcome. Maximum fistula length <2.5 cm was a predictor of treatment response, while aggregate fistula length ≥2.5 cm was a predictor of disease progression.

Conclusion

Perianal fistula length is an important imaging feature to assess on MRI of fistulizing Crohn disease.  相似文献   
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Oral verrucous hyperplasia is a whitish or pinkinsh elevated pre malignant lesion which occurs rarely. Its is also considered to be an early form of verrucous carcinoma. We have reported a case of verrucous hyperplasia which was diagnosed and treated with buccal fat pad as graft.  相似文献   
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Chondrocyte-seeded scaffolds were cultured in an ultrasound (US)-assisted bioreactor, which supplied the cells with acoustic energy around resonance frequencies (∼5.0 MHz). Polyurethane-polycarbonate (BM), chitosan (CS) and chitosan–n-butanol (CSB) based scaffolds with varying porosities were chosen and the following US regimen was employed: 15 kPa and 60 kPa, 5 min per application and 6 applications per day for 21 days. Non-stimulated scaffolds served as control. For BM scaffolds, US stimulation significantly impacted cell proliferation and depth-independent cell population density compared to controls. The highest COL2A1/COL1A1 ratios and ACAN mRNA were noted on US-treated BM scaffolds compared to controls. A similar trend was noted on US-treated cell-seeded CS and CSB scaffolds, though COL2A1/COL1A1 ratios were significantly lower compared to BM scaffolds. Expression of Sox-9 was also elevated under US and paralleled the COL2A1/COL1A1 ratio. As an original contribution, a simplified mathematical model based on Biot theory was developed to understand the propagation of the incident US wave through the scaffolds and the model analysis was connected to cellular responses. Scaffold architecture influenced the distribution of US field, with the US field being the least attenuated in BM scaffolds, thus coupling more mechanical energy into cells, and leading to increased cellular activity.  相似文献   
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