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61.
Behavioral evidence from the young suggests spatial cues that orient attention toward task‐relevant items in visual working memory (VWM) enhance memory capacity. Whether older adults can also use retrospective cues (“retro‐cues”) to enhance VWM capacity is unknown. In the current event‐related potential (ERP) study, young and old adults performed a VWM task in which spatially informative retro‐cues were presented during maintenance. Young but not older adults' VWM capacity benefited from retro‐cueing. The contralateral delay activity (CDA) ERP index of VWM maintenance was attenuated after the retro‐cue, which effectively reduced the impact of memory load. CDA amplitudes were reduced prior to retro‐cue onset in the old only. Despite a preserved ability to delete items from VWM, older adults may be less able to use retrospective attention to enhance memory capacity when expectancy of impending spatial cues disrupts effective VWM maintenance.  相似文献   
62.
A new genotyping-based DNA assay (Digene LQ®) was developed recently. The primary aim was to assess the distribution of HPV types using this new assay in atypical squamous cells of undeterminate significance (ASCUS). The secondary aim was to correlate the HPV types with the severity of the disease. The study population comprised 376 ASCUS women. The women were all Hybrid Capture II (HCII) positive and were admitted in three European referral gynecology clinics between 2007 and 2010. A colposcopy with histological examination was performed in all these patients. HPV 16 was typed in 40 % of patients, HPV 18 in 7 %, and HPV 31 in 17 %, and 18 % of patients had mixed genotypes. Patients aged over 30 more often had the HPV 16 genotype than patients aged under 30 (29 % vs. 11 %, chi-square test p < 0.001). The risk of cervical intra-epithelial neoplasia of grade 2 or more (CIN2 +) when HPV 18 positive is lower than the probability associated with HPV 16 or HPV 31: 28 % vs. 58 % and 52 %, respectively (chi-square test, p = 0.005 and p = 0.05, respectively). The Digene LQ®, a new sequence-specific hybrid capture sample preparation, is fast and efficient and allows high-throughput genotyping of 18 HR HPV types by PCR compared to traditional non-sequence-specific sample preparation methods.  相似文献   
63.
We report herein a case of blastoid variant mantle cell lymphoma (MCL) with both aberrant phenotype and unusual genetics. Unexpectedly, lymphoma cells were CD5 and CD10+. Standard karyotype and FISH techniques showed that tumor cells carried two distinct translocations which had not been reported together in a same tumor. The first translocation juxtaposed the immunoglobulin lambda light chain locus with CCND1 locus, leading to Cyclin D1 overexpression. The second translocation revealed MYC rearrangement with a non-immunoglobulin gene partner located on the short arm of chromosome 4. The interpretation of the case on tissue sections alone could have been challenging. Indeed, the lack of CD5 and expression of CD10 associated with MYC rearrangement detected on interphasic nuclei could support the diagnosis of diffuse large B-cell lymphoma or Burkitt lymphoma. This distinction is also especially important as these lymphoma subtypes require specific treatment.  相似文献   
64.

Objective

Newborn screening (NBS) identifies genetic carriers for sickle cell hemoglobinopathy and cystic fibrosis. We aimed to identify factors during initial NBS carrier results disclosure by primary care providers (PCPs) that influenced parents’ experiences and reactions.

Methods

Open-ended responses from telephone interviews with 270 parents of carriers were analyzed using mixed-methods. Conventional content analysis identified influential factors; chi-square tests analyzed relationships between factors and parent-reported reactions.

Results

Parents reported positive (35%) or negative (31%) reactions to results disclosure. Parents’ experiences were influenced by specific factors: content messages (72%), PCP traits (47%), and aspects of the setting (30%). Including at least one of five specific content messages was associated (p < 0.05) with positive parental reactions; omitting at least one of four specific content messages was associated (p < 0.05) with negative parental reactions. Parents reported positive reactions when PCPs avoided jargon or were perceived as calm. Parents reported negative reactions to jargon usage and results disclosure by voicemail.

Conclusion

Parents identified aspects of PCP communication which influenced their reactions and results disclosure experiences.

Practice implications

Our findings suggest ways PCPs may improve communication of carrier results. PCPs should provide specific content messages and consider how their actions, characteristics, and setting can influence parental reactions.  相似文献   
65.
European Journal of Clinical Microbiology & Infectious Diseases - Molecular diagnosis on nasopharyngeal swabs (NPS) is the current standard for COVID-19 diagnosis, but saliva may be an...  相似文献   
66.
67.
BackgroundUrticaria and/or angioedema (U/AE) are the most frequent and less severe forms of nonallergic hypersensitivity reactions to nonsteroidal anti-inflammatory drugs (NSAIDs). Management of NSAID-induced U/AE includes (1) the avoidance of the culprit drug and of cyclooxygenase (COX) 1 inhibitors, (2) the use of weak COX-2 inhibitors, and/or (3) desensitization to aspirin. Because these possibilities may have drawbacks, we tested the possibility of preventing NSAID-induced U/AE by the administration of antihistamines and/or a combination of antihistamines and leukotriene antagonists.ObjectiveTo test the preventive effect of antihistamines and/or leukotriene antagonists on the development of U/AE in patients with a history of NSAID hypersensitivity confirmed by a positive challenge result.MethodsA single, placebo-controlled, oral challenge using the culprit NSAID was applied to 65 patients with a history of NSAID-induced U/AE. In the case of recurrence of the symptoms, another oral challenge was performed under premedication with antihistamines alone or combined antihistamines and leukotriene antagonists.ResultsA total of 59 of 65 patients (90%) tolerated a normal dose of NSAID, confirming previous data on the poor reproducibility of nonallergic hypersensitivity reactions to NSAIDs on challenge. Of the 6 patients who experienced recurrence of the U/AE on NSAID challenge, antihistamines and combined antihistamines and leukotriene antagonists prevented the hypersensitivity reactions in 2 and 3 of them, respectively. Only 1 patient still developed a moderate NSAID-induced urticaria despite the double premedication.ConclusionTreatment with NSAIDs at normal doses is possible and well tolerated in patients who have experienced NSAID-induced U/AE, which could be prevented by the concomitant use of antihistamines and leukotriene antagonists.  相似文献   
68.

Purpose

It has been demonstrated that exercise-induced dehydration (EID) does not impair, and ad libitum drinking optimizes, cycling time-trial (TT) performance. However, the idea that EID ≥ 2 % bodyweight (BW) impairs endurance performance is well ingrained. No study has tested the impact of EID upon running TT performance. We compared the effects of thirst-driven (TD) vs. programmed fluid intake (PFI) aimed at maintaining EID-associated BW loss <2 % on half-marathon performance.

Methods

Ten trained distance runners underwent, in a randomized, crossover fashion, two, 21.1 km running TTs on a treadmill (30 °C, 42 % relative humidity) while facing a wind speed matching running speed and drinking water (1) according to thirst sensation (TD) or (2) to maintain BW loss <2 % of their pre-exercise BW (PFI), as recommended by the American College of Sports Medicine.

Results

Despite that PFI significantly reduced EID from 3.1 ± 0.6 (TD) to 1.3 ± 0.7 % BW (PFI), mean rectal temperature from 39.4 ± 0.4 to 39.1 ± 0.3 °C, mean body temperature from 38.1 ± 0.4 to 37.7 ± 0.2 °C and mean heart rate from 175 ± 9 to 171 ± 8 bpm, neither half-marathon time (TD 89.8 ± 7.7; PFI 89.6 ± 7.7 min) nor running pace (TD 4.3 ± 0.4; PFI 4.2 ± 0.4 min/km) differed significantly between trials.

Conclusion

Albeit providing trivial cardiovascular and thermoregulatory advantages, in trained distance runners, PFI (1,380 ± 320 mL/h) offers no performance benefits over TD fluid intake (384 ± 180 mL/h) during a half-marathon raced under warm conditions.  相似文献   
69.
70.
The clinical use of positive inotropic agents has been associated with increased mortality, with proarrhythmia speculated to be a contributing factor. This study compares the arrhythmogenic potential of six positive inotropic agents representing different mechanistic classes: the β-adrenergic agonist dobutamine, the adenylyl cyclase activator forskolin, the phosphodiesterase-III inhibitor milrinone, the cardiac glycoside ouabain, and the sodium channel agonists DPI 201-106 and BDF 9148. These agents were studied in dogs with anterior myocardial infarction using lower and higher dose i. v. regimens targeted to elicit 20–40% and 70–90% increases in LV+dP/dt, respectively. Precipitation of new ventricular arrhythmia by programmed ventricular stimulation was observed in all treatment groups. Incidences of new arrhythmia were comparable in the lower dose regimens, ranging from 16.7% (3/18 animals with BDF 9148) to 31.6% (6/19 animals with DPI 201-106), and in the higher dose regimens, ranging from 10.0% (1/10 animals with milrinone) to 27.7% (5/18 animals with DPI 201-106). The overall incidence of new ventricular arrhythmia ranged from 27.3% (3/11 animals with ouabain) to 47.4% (9/19 animals with DPI 201-106). No differences were observed in underlying infarct size or time from infarction to electrophysiologic study between subgroups of animals in which new arrhythmias were precipitated vs. those remaining non-responsive in any treatment group. The positive inotropic agents tested displayed diverse total group effects on heart rate, electrocardiographic intervals including QTc and ventricular refractoriness. Within individual treatment comparisons revealed a general but not universal pattern of greater ventricular refractory period values in newly inducible vs. non-inducible subgroups in the DPI 201-106, BDF 9148 and ouabain (low and high dose); milrinone and dobutamine (high dose) treatment groups. These findings indicate that regardless of underlying cellular mechanisms of action, the six positive inotropic agents tested all displayed comparable proarrhythmic potentials unrelated to underlying infarct size and time from infarction. This observation suggests the general shared property of increased myocardial contractility, potentially adversely affecting myocardial oxygen balance, myocardial perfusion and electrical stability in the setting of previous myocardial infarction, to be a common underlying cause for arrhythmogenesis. Additionally, alterations in ventricular refractoriness and repolarization may contribute significantly to proarrhythmia with some positive inotropic interventions. Received: 20 July 1999, Returned for 1. revision: 16 September 1999, 1. Revision received: 26 October 1999, Returned for 2. revision: 24 November 1999, 2. Revision received: 22 December 1999, Accepted: 6 January 2000  相似文献   
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