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141.
《Diagnostic and interventional imaging》2020,101(7-8):473-479
PurposeTo compare the evaluation of malignant focal liver lesions (FLLs) using a semi-automated RECIST tool with a standard and an ultra-low dose (ULD) computed tomography (CT) protocol.Materials and methodsThirty-four patients with malignant FLLs underwent two abdominal-pelvic CT examinations one using a standard protocol and one using an ULD protocol. There were 23 men and 11 women with a mean age 64.3 ± 14.4 (SD) years (range: 22–91 years). Dosimetric indicators were recorded, and effective dose was calculated for both examinations. Mean malignant FLL attenuation, image noise and contrast-to-noise-ratio (CNR) were compared. The largest malignant FLL per patient was evaluated using the semi-automated RECIST tool to determine longest axis length, longest orthogonal axis length, volume and World Health Organisation area.ResultsDosimetric values were significantly reduced by −56% with ULD compared to standard protocol. No differences in mean malignant FLL attenuation values were found between the two protocols. Image noise was significantly increased for all locations (P < 0.05) with ULD compared to standard protocol, and CNR was significantly reduced (P < 0.05). On the 34 malignant FLLs analyzed, six semi-automated shapes non-concordant with radiologist's visual impression were highlighted with the software, including one FLL (1/34; 3%) with standard CT acquisition only, three FLLs (3/34; 9%) with ULD CT acquisition only and two FLLs (2/34; 6%) with both CT acquisitions. After manual editing, the concordance of the values of the studied criteria between both acquisitions was good and no significant difference was reported.ConclusionSemi-automated RECIST tool demonstrates good performances using ULD CT protocol. It could be used in routine clinical practice with a ULD protocol for follow-up studies in patients with known malignant FLL. 相似文献
142.
Following the transection and repair of major nerve trunks in the forearm, the functional outcome is influenced by mechanisms in the peripheral, as well as in the central nervous system. In the present thesis the interest is focused on assessment of the outcome after nerve repair, central nervous factors influencing the outcome, and sense substitution to compensate for sensory loss. A new model instrument for routine documentation of the outcome after repair of a peripheral nerve is identified. The model includes assessments reflecting sensory, motor and pain/discomfort domains. Investigations of frequently used assessment instruments led to the construction and evaluation of a new test instrument for assessment of discriminative sensibility (tactile gnosis) to fit in the model. The summarised outcome, calculated from the model instrument and with a numerical scoring system, conforms well with the patient's opinion on the influence on activities of daily living resulting from the nerve injury, and demonstrates good reliability and validity. A reference interval for the outcome is presented, with the estimated 95% predicted values for the outcome up to five years after the nerve repair. Brain plasticity is a factor sensibility - tactile gnosis - in the adaptive process after a nerve injury, when the mind has to interpret new signal patterns, when objects are touched. For better understanding of the sensory outcome after nerve repair, central nervous factors were examined. Specific cognitive capacities, such as verbal learning and visuo-spatial logic capacity could be identified as being of importance for recovery of tactile gnosis. For patients with temporary or permanent sensory loss, a new principle for artificial sensibility based on sense substitution is presented. The hearing sense substitutes the sense of touch. The resemblance in perceptual experience between sound and touch is bridged by the stereophonic friction sound generated by touching objects, which is then amplified and transmitted to earphones. The delicate capacity of the sense of hearing to discriminate between the complex pattern of frequencies makes it reasonable to assume that hearing is able to take over functions normally devoted to touch. This is demonstrated in the thesis. 相似文献
143.
《International journal of audiology》2013,52(3):205-211
The calibration status of bone vibrators in selected audiology clinics was examined with the use of a Beltone mechanical coupler. Outputs of bone vibrators were measured and compared to Hearing Aid Industries Conference (HAIC) Interim Standard values. The results suggest that the status of calibration of bone vibrators, in the 16 clinics sampled, did not conform to HAIC Interim Standards for 76% of the measurements 相似文献
144.
《Drug discovery today》2021,26(11):2489-2495
Spiralling research costs combined with urgent pressures from the Coronavirus 2019 (COVID-19) pandemic and the consequences of climate disruption are forcing changes in drug discovery. Increasing the predictive power of in vitro human assays and using them earlier in discovery would refocus resources on more successful research strategies and reduce animal studies. Increasing laboratory automation enables effective social distancing for researchers, while allowing integrated data capture from remote laboratory networks. Such disruptive changes would not only enable more cost-effective drug discovery, but could also reduce the overall carbon footprint of discovering new drugs. 相似文献
145.
Martina Gandola Alessio Toraldo Paola Invernizzi Laura Corrado Maurizio Sberna Ignazio Santilli Gabriella Bottini Eraldo Paulesu 《Neuropsychologia》2013
Neglect patients' performance during cancellation tasks is characterized by left sided omissions and, in many cases, by the production of inappropriate material of various kinds in the ipsilesional space, e.g. additional marks over already cancelled targets, marks drawn away from targets, scribbles, irrelevant drawings. It is unclear whether these behaviours, which have collectively been called perseverative, are functionally and anatomically connected and whether they correlate with the severity of neglect. Here we report a retrospective study on 33 right brain damaged patients with neglect after right hemisphere lesions in whom we measured the intensity of perseveration of the three following kinds: (1) ‘additional marks' (AM) perseveration where patients cancelled a target with two or more well separated marks; (2) ‘scribble’ perseveration, where patients, instead of cancelling the target with a single pen stroke as required by the task, performed multiple pen strokes without breaking the pen-to-paper contact, with the final product being a scribble; (3) ‘flying marks’ (FM) perseveration where patients produced cancellation marks well away from the targets. We found that AM and FM perseveration correlated with neglect severity, while ‘scribble’ perseveration did not. The lesion-symptom mapping showed three separate anatomical areas in the right hemisphere: ‘scribble’ perseveration was associated with lesions of the orbitofrontal cortex and caudate nucleus; AM perseveration was associated with damage to the rolandic operculum, superior temporal gyrus and inferior frontal gyrus; FM perseveration was associated with damage to the dorsal premotor cortex and the temporal pole. Neglect severity followed damage to a region which grossly corresponds to the sum of the regions associated with AM and FM perseveration respectively. This complex behavioural and anatomical pattern is interpreted in terms of a three-factor model, in which AM perseveration is caused by a deficit of disengagement of attention from the right side (also causing omissions), FM perseveration is caused by directional hypokinesia (also causing left-side omissions), and ‘scribble’ perseveration is the consequence of a failure to inhibit an initiated motor act, which is completely separate (both anatomically and functionally) from the disorder inducing omissions. 相似文献
146.
147.
目的总结人工关节置换术病人的护理经验。方法对21例关节置换术病人从心理护理、术前准备、术后护理和康复指导方面帮助患者恢复肢体功能,提高生活质量。结果 21例患者中,除1例因有脑梗塞后遗症,一侧肢体活动不灵,不能早期下床活动外,其余20例患者出院前均可下床活动,肢体功能恢复好。结论人工关节置换术是帮助患者尽早恢复肢体功能和恢复生产生活的好方法。 相似文献
148.
目的:探讨联合应用消化道干预措施对降低新生儿黄疸的效果。方法:将192例正常足月新生儿随机分为直接消化道干预组、间接消化道干预组、综合组。间接消化道干预组应用游泳并抚触措施、直接消化道干预组应用早期通便措施、综合组联合应用游泳并抚触及早期通便两种措施,比较3组胎粪初排时间、胎粪转黄时间、每日排便次数、生后1~6d黄疸指数及病理性黄疸发生率。结果:综合组胎粪初排时间及胎粪转黄时间较直接消化道干预组和间接消化道干预组提前(P<0.01),每日排便次数较其他两组增多(P<0.01),生后3~6d黄疸指数及病理性黄疸发生率比两组降低(P<0.01)。结论:联合应用消化道干预措施能有效降低新生儿黄疸,减少病理性黄疸的发生率。 相似文献
149.
150.
《Journal of the American College of Radiology》2022,19(7):816-820
It seems inevitable that diagnostic and recommender artificial intelligence models will ultimately reach a point when they outperform human clinicians. Just as antibiotics displaced a host of medicinals for treating infections, the superior performance of such models will force their adoption. This article contemplates certain ethical and legal implications bearing on that adoption, especially because they involve a clinician’s exposure to allegations of malpractice. The article discusses four relevant considerations: (1) the imperative of using explainable artificial intelligence models in clinical care, (2) specific strategies for diminishing liability when a clinician agrees or disagrees with a model’s findings or recommendations but the patient nevertheless experiences a poor outcome, (3) relieving liability through legislation or regulation, and (4) comprehending such models as “persons” and therefore as potential defendants in legal proceedings. We conclude with observations on clinician–vendor relationships and argue that, although advanced artificial intelligence models have not yet arrived, clinicians must begin considering their implications now. 相似文献