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Covalent bonding of 7-chloro-4-quinolylazo-octamethoxypillar[5]arene molecules to silylated quartz substrates readily produced a new chromogenic reusable pillararene-coated quartz slide, for the direct UV detection of “transparent” analytes in solution. This device provides an analyte-selective optical response towards linear (di)amines with a highly reproducible optical read-out.

Pillar[5]arene-decorated quartz slides for the direct detection of linear amines and diamines are now available.  相似文献   
16.
The heterogeneous manifestations of MYH9‐related disorder (MYH9‐RD), characterized by macrothrombocytopenia, Döhle‐like inclusion bodies in leukocytes, bleeding of variable severity with, in some cases, ear, eye, kidney, and liver involvement, make the diagnosis for these patients still challenging in clinical practice. We collected phenotypic data and analyzed the genetic variants in more than 3,000 patients with a bleeding or platelet disorder. Patients were enrolled in the BRIDGE‐BPD and ThromboGenomics Projects and their samples processed by high throughput sequencing (HTS). We identified 50 patients with a rare variant in MYH9. All patients had macrothrombocytes and all except two had thrombocytopenia. Some degree of bleeding diathesis was reported in 41 of the 50 patients. Eleven patients presented hearing impairment, three renal failure and two elevated liver enzymes. Among the 28 rare variants identified in MYH9, 12 were novel. HTS was instrumental in diagnosing 23 patients (46%). Our results confirm the clinical heterogeneity of MYH9‐RD and show that, in the presence of an unclassified platelet disorder with macrothrombocytes, MYH9‐RD should always be considered. A HTS‐based strategy is a reliable method to reach a conclusive diagnosis of MYH9‐RD in clinical practice.  相似文献   
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Objectives

The aim of this paper is to present an overview of the current state of knowledge about dentin hypersensitivity, in terms of epidemiology, aetiology/risk factors, pain mechanisms, diagnosis and management. Available products for treatment of dentin hypersensitivity are described and scientific and clinical research validating their efficacy is reviewed.

Materials and methods

Original papers, reviews and guidelines on the subject, published both in English and in Italian from 2009 to 2013, were retrieved from the Medline/Pubmed database. Additional publications were obtained by searching the reference list of the retrieved works.

Results and conclusions

The management of dentin hypersensitivity is based on the control of causal factors and on the application, at-home or in-office, of various products aimed to occlude patent tubules. In vitro methods suffer from some limitations in mimicking “real-life” individual behaviours and ecological variables in the oral environment, therefore randomized and controlled clinical trials are considered the gold standard to evaluate the efficacy of these products. The arginine-calcium carbonate complex has proved to be efficacious in providing instant and long-lasting relief. Further randomized and controlled clinical studies are needed to confirm the results of amorphous sodium calcium phosphosilicate and strontium acetate.  相似文献   
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This monocentric, retrospective, two-stage observational study aimed to recognize the risk factors for a poor outcome in patients hospitalized with SARS-CoV-2 infection, and to develop and validate a risk score that identifies subjects at risk of worsening, death, or both. The data of patients with SARS-CoV-2 infection during the first wave of the pandemic were collected and analyzed as a derivation cohort. Variables with predictive properties were used to construct a prognostic score, which was tried out on a validation cohort enrolled during the second wave. The derivation cohort included 494 patients; the median age was 62 and the overall fatality rate was 22.3%. In a multivariable analysis, age, oxygen saturation, neutrophil-to-lymphocyte ratio, C-reactive protein and lactate dehydrogenase were independent predictors of death and composed the score. A cutoff value of 3 demonstrated a sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of 93.5%, 68.5%, 47.4% and 97.2% for death, and 84.9%, 84.5%, 79.6% and 87.9% for worsening, respectively. The validation cohort included 415 subjects. The score application showed a Se, Sp, PPV and NPV of 93.4%, 61.6%, 29.5% and 98.1% for death, and 81%, 76.3%, 72.1% and 84.1% for worsening, respectively. We propose a new clinical, easy and reliable score to predict the outcome in hospitalized SARS-CoV-2 patients.  相似文献   
19.
Pallister-Killian syndrome (PKS) is a sporadic chromosomal anomaly, caused by a tissue-specific mosaic distribution of an additional isochromosome 12p. About 60 cases of prenatal diagnosis of PKS have been reported. Only 1 case of PKS is described on the basis of prenatal screening, presenting increased nuchal translucency. An abnormal fetal facial profile is described prenatally as sonographic evidence of PKS. We report a case of prenatal diagnosis in a fetus undergoing second-level scan due to positive triple screen with ultrasound features of PKS.  相似文献   
20.
Since muscle coactivation increases the stiffness and stability of a joint, greater coactivation is likely during faster than slower movements. Very few studies, though, have been conducted to verify this hypothesis. Moreover, a large number of studies have examined coactivation of muscles surrounding the knee joint whereas there are few reports on the elbow joint. The aim of this study was therefore to compare the antagonist activation of the elbow flexors and extensors during isokinetic concentric exercises and to investigate the influence of angular velocity on their activation. Twelve men participated in the study. The surface electromyographic signals (sEMG) were recorded from the biceps brachii (BB) and triceps brachii (TB) muscles during three maximal voluntary isometric contractions (MVC) of elbow flexors and extensors and a set of three maximal elbow flexions and extensions each at 15 degrees, 30 degrees , 60 degrees, 120 degrees, 180 degrees, and 240 degrees.s(-1). Normalized root mean square (RMS) of sEMG was calculated during the isokinetic phase of movement as an index of sEMG amplitude. During elbow flexion, the antagonist activation of BB averaged 16.2% lower than TB, and this difference was statistically significant at all angular velocities. The normalized RMS values ranged from 26.0% +/- 19.0 at MVC to 37.8% +/- 13.9 at 240 degrees.s(-1) for antagonist TB activation, and from 5.7% +/- 5.2 at MVC to 18.9% +/- 8.6 at 240 degrees.s(-1) for antagonist BB activation. No influence of angular velocity on agonist and antagonist activity was found. Moreover, flexion and extension torques were both strongly affected by the amount of antagonist activation. The functional specialization of the two muscle groups could be responsible for the different levels of antagonist activation. The frequent use of BB, which is not assisted by gravity during daily activities, could lead to reduced coactivation due to a better functioning of the control system based upon reciprocal innervation. These findings may have significant implications in the design of rehabilitation programs directed to the elbow joint.  相似文献   
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