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The serrated pathway (SP) can be viewed as two parallel, but partially overlapping, arrays of colorectal precursor lesions, and their respective endpoint carcinomas, that are distinct from those of the conventional adenoma–carcinoma sequence (APC‐pathway). In this review we focus at the outset on the clinical impact, pathological features, molecular genetics and biological behaviours of the various SP cancers. Then we summarize the clinicopathological features, classification and molecular profiles of the two main precursor lesions that anchor the respective pathways: (i) sessile serrated adenoma/polyp (SSA/P), also called sessile serrated lesion (SSL), and (ii) traditional serrated adenoma (TSA). Activating mutations of the RAS–RAF–MAPK pathway initiate and sustain the lesions of the SP, and CpG island methylation of the promoter regions of tumour suppressor and DNA repair genes play the major role in their neoplastic progression. The SP includes microsatellite stable (MSS) carcinomas that are among the most biologically aggressive colorectal carcinomas (CRC), and also accounts for the great preponderance of sporadic hypermutated, mismatch repair (MMR)‐deficient or microsatellite instable (MSI) CRC. The identification, removal and appropriate classification of at‐risk SP precursors and surveillance of individuals who harbour these lesions present a challenge and opportunity for CRC prevention and mortality reduction. 相似文献
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Christopher Yeh Cem Atillasoy John T. Seykora Vivian Lee 《Journal of cutaneous pathology》2021,48(1):171-173
Respiratory cysts are benign lesions lined by normal respiratory epithelium. There are few reported cases localized to the orbit, while those of the eyelid are exceedingly rare. Respiratory cysts usually arise either from a non‐hereditary congenital malformation, where they are distinguished as choristomatous, or from trauma. Here, we report a case of a 53‐year‐old man who presented with a large right lower eyelid cyst that was histopathologically diagnosed as a respiratory cyst. 相似文献
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Co-trimoxazole is mainly used as a first-line drug for treatment and prophylaxis against Pneumocystis jiroveci pneumonia. This drug, however, has been reported as the most common causative drug for severe cutaneous adverse reactions (SCARs). This study aimed to extensively elucidate the associations between genetic polymorphisms of HLA class I and genes involved in bioactivation and detoxification of co-trimoxazole on co-trimoxazole-induced SCARS in a large sample size and well-defined Thai SCARs patients. A total of 67 patients with co-trimoxazole-induced SCARs, consisting of 51 SJS/TEN patients and 16 DRESS patients, and 91 co-trimoxazole tolerant controls were enrolled in the study. The results clearly demonstrated that the HLA-B113:01 allele was significantly associated with co-trimoxazole-induced SCARs, especially with DRESS (OR = 8.44, 95% CI = 2.66–26.77, P = 2.94 × 10−4, Pc = 0.0126). Moreover, the HLA-C108:01 allele was significantly associated with co-trimoxazole-induced SJS/TEN in the HIV/AIDS patients with an OR of 8.51 (95% CI = 2.18–33.14, P = 8.60 × 10−4, Pc = 0.0241). None of the genes involved in the bioactivation and detoxification of co-trimoxazole investigated in this study play any major role in the development of all phenotypes of SCARs. 相似文献
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Objectives:To reassess the long-term camouflage effects of resin infiltration (Icon, DMG, Hamburg, Germany) of white spot lesions (WSL) and sound adjacent enamel (SAE) achieved in a previous trial. The null hypothesis was tested that there were no significantly different CIE-L*a*b*-ΔE-values between WSL and SAE areas of assessment after at least 24 months (T24) compared to those at baseline (T0).Materials and Methods:Of twenty subjects who received previous resin infiltration treatment of nteeth = 111 nonrestored, noncavitated postorthodontic WSL after multibracket treatment during a randomized controlled trial and were contacted 20 months after baseline, eight subjects (trial teeth nteeth = 40; m/f ratio 1/7; age range (mean; SD) 12–17 [15.25; 2.12] years); response rate: 40%) were available for follow-up after at least 24 months (T24). CIE-L*a*b* differences between summarized color and lightness values (ΔEWSL/SAE) of WSL and SAE were assessed using a spectrophotometer and compared to baseline data assessed prior to infiltration (T0), and those after 6 (T6), and 12 (T12) months using paired t tests at a significance level of α = 5%.Results:T24 assessments were performed after a mean 33.86 (SD: 8.64; Min: 24; Max: 45) months following T0. Mean (SD) ΔEWSL/SAE units of available teeth were 8.76 (5.33) at baseline; 5.5 (2.75) at T6; 5.2 (2.41) at T12; and 5.57 (2.6) at T24. Comparisons of T6, T12, and T24 with T0 yielded highly significant differences, whereas T6–T24 and T12–T24 differences were found to be not significant.Conclusions:Assimilation of infiltrated WSL to the color of adjacent enamel by resin infiltration is considered to be suitable for the long-term improvement in the esthetic appearance of postorthodontic WSL. 相似文献
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Thomas Asendorf Robin Henderson Heinz Schmidli Tim Friede 《Statistics in medicine》2019,38(9):1503-1528
In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis. 相似文献
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刘彦鹏 《中国卫生标准管理》2020,(5):95-97
目的探讨参附注射液对老年重症肺炎疗效及N末端B型利钠肽原(NT-pro BNP)的影响。方法选择2016年6月—2019年6月医院收治的老年重症肺炎患者80例,以随机数表法将其分为两组,即对照组与研究组各40例。对照组患者接受常规对症治疗,研究组在此基础上应用参附注射液治疗。对比两组临床疗效,治疗前与治疗3 d、5 d时血浆NT-pro BNP水平,以及不良反应情况。结果研究组治疗的总有效率为95.00%,高于对照组77.50%(P<0.05)。治疗后3 d与5 d时研究组血浆NT-pro BNP水平均低于对照组(P<0.01)。两组治疗期间均未见明显的药物不良反应。结论参附注射液能够有效提高老年重症肺炎患者的疗效,调节脑钠肽水平。 相似文献