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Hypertrophic lichen planus (HLP) is a T‐cell‐mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24‐year‐old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated.  相似文献   
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在了解及处理坚持用药的情况较差时,医生往往遇到很多困难。困扰医生的一个主要问题是,如何护理患有急性或危及生命的疾病而不能长期坚持治疗的儿童。对医生来说,更难的是如何了解父母何时不能为子女提供适当的护理。近30%~70%的患慢性疾病者,因为治疗时间长、服用的药物种类多及症状时有缓解而不能坚持用药。临床经验表明,患有慢性疾病,如囊性纤维化、癫痫、哮喘、糖尿病患者坚持用药的情况较差。  相似文献   
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Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia.  相似文献   
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A total of 15 mixtures involving 9 different stocks attributed to the 19/20, 32 and 39 major clonal genotypes of Trypanosoma cruzi were used to infect third-instar nymphs of Triatoma infestans via an artificial feeding device. Three biological parameters were considered: (1) the percentage of infected insects (%II), (2) the number of flagellates per insect (NFI), and (3) the percentage of trypomastigotes per insect (%DIF). Genetic characterization by both multilocus enzyme electrophoresis (MLEE) and random amplification of polymorphic DNA (RAPD) indicated that in almost all cases (87%), mixtures remained present after completion of the whole cycle in the insect vector. Two lines of comparison were performed: (1) pure clonal genotypes versus corresponding mixed clonal genotypes and (2) the␣actual behavior of mixed clonal genotypes versus the expected behavior of the theoretical mixture (i.e. the␣arithmetic mean of the results observed for each of the two clonal genotypes taken separately). Statistical analyses of the variables were made difficult because of the presence of large standard deviations. Nevertheless, in several cases, mixtures differed significantly from pure clonal genotypes, and in one case the actual mixture differed significantly from the theoretical mixture. In some cases, interaction (either potentialization or reciprocal inhibition) could be suspected. Received: 10 March 1997 / Accepted: 21 September 1997  相似文献   
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Impaired conditioned taste aversion learning in APP transgenic mice   总被引:8,自引:0,他引:8  
Cognition in transgenic mouse models of Alzheimer's disease (AD) has been predominantly characterized in explicit spatial orientation tasks. However, dementia in AD encompasses also implicit memory systems. In the present study a line of transgenic mice (TgCRND8) encoding a double mutated allele of the human amyloid precursor protein (APP) genes was evaluated in an implicit associative learning task of conditioned taste aversion (CTA). CTA is a form of Pavlovian classical conditioning, in which a mouse learns to avoid a novel taste of saccharine (conditioned stimulus) paired with an experimentally induced (systemic injection of lithium chloride) nausea (unconditioned stimulus). In contrast to conditioned non-Tg mice, TgCRND8 APP mice developed weaker aversion against saccharine and quickly increased its consumption in repeated tests. These results indicate that TgCRND8 mice show a significant impairment not only in explicit spatial memory, as has been previously shown [Nature 408 (2000) 979], but also in implicit memory. Control experiments confirmed that TgCRND8 and non-Tg mice had comparable taste sensitivities in response to appetitive as well as aversive tastes. The study suggests that the CTA paradigm can be a sensitive tool to evaluate deficits in implicit associative learning in APP transgenic mouse models of AD.  相似文献   
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Diet has been associated with the risk of depression, whereas different subtypes of depression have been linked with different cardiovascular risk factors (CVRFs). In this study, our aims were to (1) identify dietary patterns with exploratory factor analysis, (2) assess cross-sectional associations between dietary patterns and depression subtypes, and (3) examine the potentially mediating effect of dietary patterns in the associations between CVRFs and depression subtypes. In the first follow-up of the population-based CoLaus|PsyCoLaus study (2009–2013, 3554 participants, 45.6% men, mean age 57.5 years), a food frequency questionnaire assessed dietary intake and a semi-structured interview allowed to characterize major depressive disorder into current or remitted atypical, melancholic, and unspecified subtypes. Three dietary patterns were identified: Western, Mediterranean, and Sweet-Dairy. Western diet was positively associated with current atypical depression, but negatively associated with current and remitted melancholic depression. Sweet-Dairy was positively associated with current melancholic depression. However, these dietary patterns did not mediate the associations between CVRFs and depression subtypes. Hence, although we could show that people with different subtypes of depression make different choices regarding their diet, it is unlikely that these differential dietary choices account for the well-established associations between depression subtypes and CVRFs.  相似文献   
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