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Mycobacteria cause a range of diseases in both immunocompetent and immunosuppressed individuals and may affect many different organs. The most noticeable recent change in patterns of cutaneous mycobacterial infection refers to the increase in non‐tuberculous mycobacterial (NTM) infections. This review focuses on the clinical manifestations, diagnosis, and treatment of cutaneous NTM infections. The MEDLINE, PubMed, and Cochrane Library databases were searched using the keywords “non‐tuberculous mycobacteria,” “atypical mycobacteria,” and “mycobacteria other than tubercle bacilli”. Publications on cutaneous NTM infections written in English were included in this review. Literature published by the World Health Organization was examined for further material. References in review articles were screened for other studies not already identified. The clinical features, diagnosis, and treatment of NTM infections were reviewed. Cutaneous mycobacterial disease may take many guises and may appear benign in nature. Chronic cutaneous lesions at the sites of trauma or surgical procedures, especially those that fail to respond to standard antibiotic therapy, should prompt the consideration of mycobacterial disease. The lack of rapid techniques for the identification of pathogens makes diagnosis challenging. The lack of randomized controlled trials on the efficacy of antimicrobial agents means that empiric therapy may fail, necessitate prolonged combinations of antibiotics, and increase the probability of side effects and diminished compliance.  相似文献   
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Five percent of patients with liver secondaries from colorectal carcinoma are potentially resectable and several studies have demonstrated significantly improved survival following resection. Two hundred and ten patients operated for colorectal carcinoma were followed up. Computed tomography confirmed potentially resectable metastasis to the liver in 38. On exploration 18 patients who had 4 or less hepatic metastases and no extrahepatic disease, underwent resection of their secondaries. Fourteen were males and 4 females with a mean age of 43.5 (SD 13.6, range 18-72) years. Ten patients presented with synchronous liver metastasis and 8 had metachronous disease. There was no post-operative mortality. All 18 have been followed up. for a median period of 23.5 (range 12-38) months. Seven patients are alive and well with no evidence of recurrence at a median period of 28 months (survival 39%). Four are alive with local recurrence in the liver. Median time to recurrence was 22 months. Seven patients have died of disseminated disease. The disease free survival at 28 months is 39% and the overall survival 61%. A close follow-up protocol for all patient undergoing curative surgery for colorectal cancer is essential, if such patients are to be selected early.KEY WORDS: Colorectal cancer, Liver resection, Metastases  相似文献   
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To date, the term oral leukoplakia (OL) should be used to recognize ‘predominantly white plaques of questionable risk, having excluded (other) known diseases or disorders that carry no increased risk of cancer’. In this review, we addressed four controversial topics regarding oral leukoplakias (OLs): (i) Do tobacco and alcohol cause OLs?, (ii) What percentage of OLs transform into oral squamous cell carcinoma (OSCC)?, (iii) Can we distinguish between premalignant and innocent OLs?, and (iv) Is proliferative verrucous leukoplakia (PVL) a specific entity or just a form of multifocal leukoplakia? Results of extensive literature search suggest that (i) no definitive evidence for direct causal relationship between smoked tobacco and alcohol as causative factors of OLs, (ii and iii) the vast majority of OLs follow a benign course and do not progress into a cancer, and no widely accepted and/or validated clinical and/or biological factors can predict malignant transformation, and (iv) the distinction between multifocal/multiple leukoplakias and PVL in their early presentation is impossible; the temporal clinical progression and the high rate of recurrences and development of cancer of PVL are the most reliable features for diagnosis.  相似文献   
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OBJECTIVES: To compare relevance, accessibility, role in the teaching-learning process, and user preference, of identical case-study-based teaching programmes in CAL and booklet format. DESIGN: Questionnaire assessment. SUBJECTS AND SETTING: Dental students at Sheffield Dental School. METHODS: 54 5th-year dental students were self-grouped as computer novice (n = 26) or proficient (n = 23) and sub-groups of 12 randomly selected from each. Half of each sub-group tested the CAL programme first and half the booklet-based programme, with cross-over, after 6 weeks. Assessment of packages was carried out immediately after use, and 2 weeks after completion, a further assessment was made on the basis of preference and value as a teaching medium. RESULTS: All subjects thought both packages relevant to clinical practice and written at an appropriate level, and the majority found the text, illustrations and tasks clear. Both groups competed the CAL package more quickly. Students asked to use such packages in the future,viewing them as support for, rather than replacement of, present teaching. The majority of computer-proficient students preferred CAL, considering it the superior teaching medium. CONCLUSIONS: Both CAL and booklet case-study materials were considered useful in addition to, rather than as a replacement for, other teaching methods. Most considered the CAL superior and preferred it. Nevertheless, while past computer experience determined preference for the format, it did not influence ability to access the medium. Future use of such materials is probably best in relation to preparation for tutorials and clinics. A key role is its availability as a revision aid.  相似文献   
999.
Depth of invasion is an important predictor of survival. A study by the International Consortium (ICOR) for Outcome Research proposed incorporation of it (together with the greatest surface dimension, or the anatomical criteria, or both) into the T stage. This has been adopted in part by the 8th edition of the Union for International Cancer Control (UICC) TNM 8 classification of malignant tumours for oral squamous cell carcinoma (SCC). Our aim was to verify depth of invasion as an independent prognostic factor, and to validate the staging by comparing it with that specified in the 7th edition (TNM 7) and the T-staging model proposed by the International Consortium. We retrospectively studied 449 patients who had had operations for a previously untreated primary oral cancer between 2006 and 2014 at a single centre, and analysed the independent predictive value of depth of invasion for both disease-specific and overall survival. It was an independent predictor of disease-specific survival as were sex, perineural invasion, and N stage. It was also an independent predictor of overall survival together with sex and N status. Staging in TNM 8 gave a better balance of distribution than that in TNM 7, but did not discriminate between prognosis in patients with T3 and T4 disease. The proposed International Consortium rules for T-staging gave an improved balance in distribution and hazard discrimination. The incorporation of depth of invasion into the T-staging rules for oral SCC improved prognostic accuracy and is likely to influence the selection of patients for adjuvant treatment. Our findings suggest that the TNM 8 staging lacks hazard discrimination in patients with locally-advanced disease because its T4 staging is restricted to anatomical criteria.  相似文献   
1000.
OBJECTIVES: The aim of this study was to evaluate the effect of aortic valve replacement (AVR) on left ventricular (LV) function and LV remodeling, comparing patients with aortic valve stenosis to patients with aortic regurgitation. BACKGROUND: Aortic valve disease is associated with eccentric or concentric LV hypertrophy and changes in LV function. The relationship between LV geometry and LV function and the effect of LV remodeling after AVR on diastolic filling, in patients with aortic valve stenosis compared with aortic regurgitation, are largely unknown.Nineteen patients with aortic valve disease (12 aortic valve stenosis, 7 aortic regurgitation) were studied using magnetic resonance imaging to assess LV geometry and LV function before and 9 +/- 3 months after AVR. Ten age-matched healthy males served as control subjects. RESULTS: Before AVR, the ratio between left ventricular mass index (LVMI) and left ventricular end-diastolic volume index (LVEDVI) was only increased in patients with aortic valve stenosis (1.37 +/- 0.16 g/ml) compared with control subjects (0.93 +/- 0.08 g/ml, p < 0.05). After AVR, LVMI/LVEDVI decreased significantly in aortic valve stenosis (to 1.15 +/- 0.14 g/ml, p < 0.0001), but increased significantly in aortic regurgitation (1.02 +/- 0.20 g/ml to 1.44 +/- 0.27 g/ml, p < 0.0001). Before AVR, diastolic filling was impaired in both aortic valve stenosis and aortic regurgitation. Early after AVR, diastolic filling improved in patients with aortic valve stenosis, whereas patients with aortic regurgitation showed a deterioration in diastolic filling. CONCLUSIONS: Early after AVR, patients with aortic valve stenosis show a decrease in both LVMI and LVMI/LVEDVI and an improvement in diastolic filling, whereas in patients with aortic regurgitation, LVMI decreases less rapidly than LVEDVI, causing concentric remodeling of the LV, most likely explaining the observed deterioration of diastolic filling in these patients.  相似文献   
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