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991.
Lichen planus pigmentosus is a rare variant of lichen planus for which no effective treatment is currently available. Patients usually present with hyperpigmented, dark brown macules on sun‐exposed areas or flexural folds. Here we describe a 50‐year‐old Chinese woman who had biopsy‐confirmed lichen planus pigmentosus that was recalcitrant to a variety of topical treatments, but responded to treatment with a pigment laser. 相似文献
992.
Adrian P Wiegmans Fares Al-Ejeh Nicole Chee Pei-Yi Yap Julia J Gorski Leonard Da Silva Emma Bolderson Georgia Chenevix-Trench Robin Anderson Peter T Simpson Sunil R Lakhani Kum Kum Khanna 《Oncotarget》2014,5(10):3261-3272
In contrast to extensive studies on familial breast cancer, it is currently unclear whether defects in DNA double strand break (DSB) repair genes play a role in sporadic breast cancer development and progression. We performed analysis of immunohistochemistry in an independent cohort of 235 were sporadic breast tumours. This analysis suggested that RAD51 expression is increased during breast cancer progression and metastasis and an oncogenic role for RAD51 when deregulated. Subsequent knockdown of RAD51 repressed cancer cell migration in vitro and reduced primary tumor growth in a syngeneic mouse model in vivo. Loss of RAD51 also inhibited associated metastasis not only in syngeneic mice but human xenografts and changed the metastatic gene expression profile of cancer cells, consistent with inhibition of distant metastasis. This demonstrates for the first time a new function of RAD51 that may underlie the proclivity of patients with RAD51 overexpression to develop distant metastasis. RAD51 is a potential biomarker and attractive drug target for metastatic triple negative breast cancer, with the capability to extend the survival of patients, which is less than 6 months. 相似文献
993.
Zenobia C. D'Costa Catherine Higgins Chee Wee Ong Gareth W. Irwin David Boyle Darragh G. McArt Karen McCloskey Niamh E. Buckley Nyree T. Crawford Lalitha Thiagarajan James T. Murray Richard D. Kennedy Karl A. Mulligan D. Paul Harkin David J.J. Waugh Chris J. Scott Manuel Salto-Tellez Richard Williams Paul B. Mullan 《Oncotarget》2014,5(6):1609-1620
994.
Bo Hwa Choi Sung Min Ko Je Kyoun Shin Hyun Keun Chee Jun Seok Kim 《Korean journal of radiology》2021,22(6):890
ObjectiveTo identify the association between morphological and functional characteristics of the bicuspid aortic valve (BAV) and bicuspid aortopathy and to identify the determinants of aortic dilatation using transthoracic echocardiography (TTE) and cardiac computed tomography (CCT).Materials and MethodsThis study included 312 subjects (mean [SD] age, 52.7 [14.3] years; 227 males [72.8%]) who underwent TTE and CCT. The BAVs were classified by anterior-posterior (BAV-AP) or right-left (BAV-RL) orientation of the cusps and divided according to the presence (raphe+) or absence of a raphe (raphe−) based on the CCT and intraoperative findings. The dimensions of the sinus of Valsalva and the proximal ascending aorta were measured by CCT. We assessed the determinants of aortic root and proximal ascending aortic dilatation (size index > 2.1 cm/m2) by Univariable and multivariable logistic regression analyses.ResultsOf the 312 patients, BAV-AP was present in 188 patients (60.3%), and 185 patients (59.3%) were raphe+. Moderate-to-severe aortic stenosis (AS) was the most common hemodynamic abnormality (54.8%). The most common type of aortopathy was the combined dilated root and mid-ascending aortic phenotype (62.5%). On multivariable analysis, age and AS severity were significantly associated with aortic root dilatation (p < 0.05), and age, sex, and AS severity were significantly associated with ascending aortic dilatation (p < 005). However, the orientation of the cusps, presence of a raphe, and severity of aortic regurgitation were not associated with aortic root and ascending aortic dilatation.ConclusionBAV morphological characteristics were not determinants of aortic dilatation. Age, sex, and AS severity were predictors of bicuspid aortopathy. Therefore, age, sex, and AS severity, rather than valve morphology, need to be considered when planning treatment for BAV patients. 相似文献
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996.
Singapore has experienced a rise in the tuberculosis (TB) incidence rate among her local population since 2008, which we believe, is contributed in no small part to a recent increase in community transmission due to delayed diagnosis of infectious pulmonary TB cases. Data from the TB notification registry showed an increase from 2004 to 2008 in the number and proportion of sputum acid-fast bacilli smear-positive pulmonary TB cases with prolonged cough. Two surveys at the TB Control Unit showed that healthcare system delays exceeded patient delay in seeking medical consultation. There is thus an urgent need to heighten TB awareness among the public and the medical community in order to reduce the time taken to diagnose infectious TB cases in Singapore. 相似文献
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999.
Fetal DNA is present in the plasma of pregnant women. A fetus with trisomy of a chromosome will release an increased amount of DNA from that chromosome into maternal plasma. Such an increase has previously been measured using methods that allow individual DNA molecules to be counted. One such method involves the use of random massively parallel sequencing of maternal plasma DNA. As the sequencing process is random, sequence tags from a potentially aneuploid chromosome only represent a fraction of the sequencing data. The performance of selective amplification and sequencing of specific genomic regions is a recently reported approach for focusing the sequencing power onto genomic regions of diagnostic interest. This article provides a critical analysis of this approach and puts this method in the perspective of other recent works in the field. 相似文献
1000.
STATEMENT OF PROBLEM: Monophase and dual-viscosity impression techniques are available with little knowledge of which one might render better quality under wet and dry surface conditions. PURPOSE: The purpose of this study was to determine whether type of material, viscosity selection, and presence of moisture affect detail reproduction of elastomeric impressions. MATERIALS AND METHODS: Single-viscosity systems were polyether (Impregum Penta) and vinyl polysiloxanes (President MonoBody, Extrude MPV, and Aquasil). Dual-viscosity systems included polyether (Impregum Penta/Permadyne Garant) and vinyl polysiloxanes (Dimension Penta H/Dimension Garant L, Extrude Extra/Extrude Wash, and Aquasil/Aquasil LV). Impressions were made of a surface analyzer calibration standard possessing a uniform "saw-tooth" pattern with a mean roughness (Ra) of 2.87 mum, which was one fourth of the peak-to-valley height. Each of the 8 impression groups was subjected to dry (control) and wet conditions. The wet condition consisted of 3 mL of distilled water applied to the surface of the standard but allowed to escape during the procedure. Eighty impressions were made, 5 for each test group. After setting, the surface of each impression was scanned at 5 locations using a Surfanalyzer 4000. A 3-factor ANOVA and Student-Newman-Kuels test were used to analyze the data (alpha=.05). RESULTS: There were significant differences between polyether and vinyl polysiloxane materials, dual and monophase techniques, and the 2 surface conditions (P<.05). Cross-product interactions were not significant, allowing comparison of mean values for each factor. The mean Ra for single viscosity was 2.21 mum versus 1.67 mum for dual viscosity; polyether was 2.12 mum versus 1.89 mum for addition silicone; and under dry conditions, the mean was 2.04 mum versus 1.86 mum for wet conditions. CONCLUSION: Single-viscosity systems reproduced the standard saw-tooth pattern better than the dual-viscosity systems, as did polyether impression materials compared to addition silicones. Moisture led to a lower Ra or less detail compared to dry conditions. 相似文献