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991.
《Radiography》2020,26(4):e251-e257
IntroductionThe NHS breast screening programme only employs female mammographers to carry out breast screening. The screening service is experiencing a shortage of staff and introducing male mammographers into the service is a potential solution. This research aimed to determine if the introduction of male mammographers would impact acceptance rates of the offer of screening, how women feel about the potential change and what the impact would be at a programme level.MethodsThe research was conducted in 3 stages. Initially 24 face-to-face interviews were conducted with women aged 45–70 and 19 interviews over the telephone with stakeholders; these interviews explored what women's reaction would be to the introduction of male mammographers. These interviews informed the content of a questionnaire that was completed online by 1000 women aged 50–71. It explored what women would do if offered a test with a male mammographer and how they felt about the potential change.ResultsOver half, 53.4% stated they would attend a routine mammogram if the mammographer was male, 15.3% said they would attend if a female chaperone was present, and 31.3% stated they would refuse to attend. The face-to-face interviews suggested women view routine breast screening differently to other healthcare interactions because it is an optional service and not a treatment. As a result, participants had higher expectations both in terms of expecting a choice over the gender of the mammographer and a need to feel comfortable.Conclusion and implications for practiceThe findings indicate that the percentage of eligible women attending breast screening may decrease if male mammographers were introduced. This impact of introducing male mammographers would need to be carefully weighed up against the potential gains in workforce numbers in opening up mammography to male practitioners.  相似文献   
992.
Pre-participation cardiovascular screening (PPCS) is recommended by several scientific and sporting organizations on the premise that early detection of cardiac disease provides a platform for individualized risk assessment and management; which has been proven to lower mortality rates for certain conditions associated with sudden cardiac arrest (SCA) and sudden cardiac death (SCD). What constitutes the most effective strategy for PPCS of young athletes remains a topic of considerable debate. The addition of the electrocardiogram (ECG) to the medical history and physical examination undoubtedly enhances early detection of disease, which meets the primary objective of PPCS. The benefit of enhanced sensitivity must be carefully balanced against the risk of potential harm through increased false-positive findings, costly downstream investigations, and unnecessary restriction/disqualification from competitive sports. To mitigate this risk, it is essential that ECG-based PPCS programs are implemented by institutions with a strong infrastructure and by physicians appropriately trained in modern ECG standards with adequate cardiology resources to guide downstream investigations. While PPCS is compulsory for most competitive athletes, the current debate surrounding ECG-based programs exists in a binary form; whereby ECG screening is mandated for all competitive athletes or none at all. This polarized approach fails to consider individualized patient risk and the available sports cardiology resources. The limitations of a uniform approach are highlighted by evolving data, which suggest that athletes display a differential risk profile for SCA/SCD, which is influenced by age, sex, ethnicity, sporting discipline, and standard of play. Evaluation of the etiology of SCA/SCD within high-risk populations reveals a disproportionately higher prevalence of ECG-detectable conditions. Selective ECG screening using a risk-based approach may, therefore, offer a more cost-effective and feasible approach to PPCS in the setting of limited sports cardiology resources, although this approach is not without important ethical considerations.  相似文献   
993.
目的:临床药师通过儿童营养风险筛查工具STRONGkids (screening tool risk on nutritional status and growth)评分观察不同营养风险等级的肠套叠患儿使用肠外营养支持对营养指标、术后恢复情况等是否有影响,根据结果对医生进行宣教并干预,推动肠外营养的使用更加合理,减少住院费用和不良反应的发生。方法:采用STRONGkids评分对肠套叠患儿进行营养风险筛查,根据STRONGkids评分的不同分值将患儿分组,各组按仅使用肠外营养、未使用任何营养支持再分为A、B组,分别统计2组的比例,以及术后第7天患儿营养指标、术后恢复情况和住院费用,观察不同分值组肠外营养使用率以及使用肠外营养是否有必要。临床药师根据研究结果与医生沟通并干预,1年后比较干预前后肠外营养使用率、不良反应发生率及住院费用等。结果:1~2分的患儿中A组与B组在营养指标、术后住院时间上没有显著差异,但A组住院费用显著高于B组;3分的患儿中B组较A组患儿的体质量、前白蛋白、视黄醇结合蛋白显著降低,住院天数A组显著短于B组;总体使用肠外营养的患儿不良反应发生率更高。临床药师根据上述结果指导医生根据相关指南对肠外营养适应证进行探讨和改进。干预1年后再次统计,STRONGkids评分1分组肠外营养使用率由77.78%下降至7.50%,2分组由85.42%下降至17.65%;总体不良反应发生率由18.80%下降至7.27%,住院费用由16 599.50±1 952.22元下降至14 647.09±2 300.16元,差异均有显著性。结论:通过临床药师干预,低营养风险患者肠外营养使用率降低,合理性增加,患者住院期间不良反应发生率及住院费用降低。临床药师在推动肠外营养合理使用中发挥了重要作用。  相似文献   
994.
995.
Electrostatic counter ion screening is a phenomenon that is detrimental to the sensitivity of charge detection in electrolytic environments, such as in field-effect transistor-based biosensors. Using simple analytical arguments, we show that electrostatic screening is weaker in the vicinity of concave curved surfaces, and stronger in the vicinity of convex surfaces. We use this insight to show, using numerical simulations, that the enhanced sensitivity observed in nanoscale biosensors is due to binding of biomolecules in concave corners where screening is reduced. We show that the traditional argument, that increased surface area-to-volume ratio for nanoscale sensors is responsible for their increased sensitivity, is incorrect.In recent years, there has been a major drive to use field-effect transistor (FET)-based devices to detect biological molecules in electrolytic environments (1). These biosensors use the charge of biomolecules to gate the current through a transistor (2). Frequently, the transistor is based on a quasi-1D nanostructure, such as a nanowire (NW) or nanotube, and the biomolecules bind directly to the surface of the nanoscale structure (1, 3). The use of such nanostructures is justified by the belief that nanoscale biosensors are more sensitive, with sensitivity defined as the relative change in drain current or a shift in threshold voltage in response to a change in bound biomolecule density. A few experiments specifically studied the effect of shrinking nanowire radii on sensitivity, albeit with varying structures, analytes, and sensing circumstances, and found that shrinking a sensor’s dimensions indeed improves its sensitivity (46). The enhanced sensitivity has been loosely attributed to the increase in the sensor’s surface area-to-volume ratio, which is a direct result of shrinking its dimensions. This argument has been analytically justified in the context of gas sensors (7). However, there is a fundamental difference between gas and biomolecule sensing: biomolecule sensing is performed in an electrolyte, and the ions therein will screen the charge of bound biomolecules in a phenomenon known as Debye screening (8, 9). The direct application of the gas sensing result to the biosensing environment implicitly assumes that the screening effect does not change with shrinking dimensions, an assumption we believe to be false. There have been studies that included a rigorous treatment of screening in biosensors, but they studied neither the specific cause of increased sensitivity at the nanoscale, nor the effect of varying size on screening behavior (10). We believe the phenomenon responsible for the increased sensitivity of nanowires in particular, and nanostructured biosensors in general, have not yet been uncovered by the research community.We have previously dissected the operation of biosensors into two independent parts to better understand the underlying physics (11): first, biomolecule charges cause a change in the local electrostatic potential at the outer surface of the gate dielectric. This potential change in turn causes a change in the drain current of the underlying semiconductor channel. The latter part is simply the transconductance effect of an FET-based transistor; nanoscale biosensors have no advantage in this respect over planar sensors. The nanoscale advantage should therefore lie in the first part of the sensor operation, which is a capacitive transduction effect, dominated by the capacitance of the Debye screening layer. We therefore believe understanding screening behavior at the nanoscale is key to understanding the behavior of nanoscale biosensors.In this paper, we revisit screening near curved nanostructure surfaces by solving the Poisson–Boltzmann equation that led to the original Debye–Hückel formalism. Our simple analytical arguments will show that screening is stronger near surfaces with convex curvature, and weaker near surfaces with concave curvature. We only consider simple convex and concave surfaces because almost all nonplanar surfaces can be decomposed into local areas with either convex or concave curvature.Next, we apply the basic insight we gain from the previous step to understand and analyze the specific case of nanowire biosensors. Increasing the surface area-to-volume ratio of nanowire sensors actually means increasing their convexity, which should result in increased Debye screening and reduced sensitivity. However, nanowires placed on insulating substrates create concave corners between the nanowire and the substrate. We believe biomolecules bound in such concave corners are responsible for the increased sensitivity experimentally observed in nanowires.  相似文献   
996.
997.
ObjectiveThere is insufficient large-scale evidence for screening mammography in women <40 years at elevated risk. This study compares risk-based screening of women aged 30 to 39 with risk factors versus women aged 40 to 49 without risk factors in the National Mammography Database (NMD).MethodsThis retrospective, HIPAA-compliant, institutional review board–exempt study analyzed data from 150 NMD mammography facilities in 31 states. Patients were stratified by 5-year age intervals, availability of prior mammograms, and specific risk factors for breast cancer: family history of breast cancer, personal history of breast cancer, and dense breasts. Four screening performance metrics were calculated for each age and risk group: recall rate (RR), cancer detection rate (CDR), and positive predictive values for biopsy recommended (PPV2) and biopsy performed (PPV3).ResultsData from 5,986,131 screening mammograms performed between January 2008 and December 2015 in 2,647,315 women were evaluated. Overall, mean CDR was 3.69 of 1,000 (95% confidence interval: 3.64-3.74), RR was 9.89% (9.87%-9.92%), PPV2 was 20.1% (19.9%-20.4%), and PPV3 was 28.2% (27.0%-28.5%). Women aged 30 to 34 and 35 to 39 had similar CDR, RR, and PPVs, with the presence of the three evaluated risk factors associated with significantly higher CDR. Moreover, compared with a population currently recommended for screening mammography in the United States (aged 40-49 at average risk), incidence screening (at least one prior screening examination) of women aged 30 to 39 with the three evaluated risk factors has similar cancer detection rates and recall rates.DiscussionWomen with one or more of these three specific risk factors likely benefit from screening commencing at age 30 instead of age 40.  相似文献   
998.
PurposeThe aims of this study were to determine the prevalence and outcomes of extrapulmonary malignancies identified on lung cancer screening (LCS) and to determine the cost associated with the investigation of these lesions.MethodsThis retrospective study included 7,414 low-dose CT studies performed between June 2014 and December 2019 on 4,160 patients as part of an established LCS program. Patients with indeterminate extrapulmonary lesions were identified, and the diagnostic workup, management, and outcomes of the lesions were determined. Costs related to diagnostic evaluation were estimated using 2020 total facility relative value units and the 2020 Medicare conversion factor. Out-of-pocket costs were extracted from billing records.ResultsThere were 20 extrapulmonary malignancies among 241 reported lesions in 225 patients (mean age, 66.1 ± 6.4 years; 109 men, 116 women). The prevalence of extrapulmonary malignancy was 20 of 4,160 (0.48%). Early-stage cancers were detected in 13 of 20 (65%). No cancer-specific mortality was observed. The predictive value for malignancy varied by organ (P = .03) and was highest in the chest wall and axilla (36.4%), followed by bone (25%). The average cost on the basis of Medicare reimbursement for diagnosis of an extrapulmonary malignancy on LCS was $1,316.03 ($6.33 per participant and $109.21 per indeterminate incidental lesion). Most patients (203 of 225 [90.2%]) did not have out-of-pocket costs related to diagnostic workup. In those who did, the median cost was $160.60 (range, $75-$606.76).ConclusionsLow-dose CT for LCS detects extrapulmonary malignancy with high predictive value for certain locations. There is cost associated in the workup related to these incidental lesions, but most malignancies are detected at early stages and have good outcomes.  相似文献   
999.
BackgroundThe risks from potential exposure to coronavirus disease 2019 (COVID-19), and resource reallocation that has occurred to combat the pandemic, have altered the balance of benefits and harms that informed current (pre-COVID-19) guideline recommendations for lung cancer screening and lung nodule evaluation. Consensus statements were developed to guide clinicians managing lung cancer screening programs and patients with lung nodules during the COVID-19 pandemic.MethodsAn expert panel of 24 members, including pulmonologists (n = 17), thoracic radiologists (n = 5), and thoracic surgeons (n = 2), was formed. The panel was provided with an overview of current evidence, summarized by recent guidelines related to lung cancer screening and lung nodule evaluation. The panel was convened by video teleconference to discuss and then vote on statements related to 12 common clinical scenarios. A predefined threshold of 70% of panel members voting agree or strongly agree was used to determine if there was a consensus for each statement. Items that may influence decisions were listed as notes to be considered for each scenario.ResultsTwelve statements related to baseline and annual lung cancer screening (n = 2), surveillance of a previously detected lung nodule (n = 5), evaluation of intermediate and high-risk lung nodules (n = 4), and management of clinical stage I non–small-cell lung cancer (n = 1) were developed and modified. All 12 statements were confirmed as consensus statements according to the voting results. The consensus statements provide guidance about situations in which it was believed to be appropriate to delay screening, defer surveillance imaging of lung nodules, and minimize nonurgent interventions during the evaluation of lung nodules and stage I non–small-cell lung cancer.ConclusionsThere was consensus that during the COVID-19 pandemic, it is appropriate to defer enrollment in lung cancer screening and modify the evaluation of lung nodules due to the added risks from potential exposure and the need for resource reallocation. There are multiple local, regional, and patient-related factors that should be considered when applying these statements to individual patient care.  相似文献   
1000.
Non-AIDS defining malignancies, particularly colorectal cancer (CRC), may be more prevalent among persons living with HIV (PLWH). Further, PLWH may be less likely to receive CRC screening (CRCS). We studied the epidemiology of CRC and CRCS patterns in PLWH and HIV-uninfected persons in a large US Medicaid population. We performed a matched cohort study examining CRC incidence in 2006 and CRCS between 1999 and 2007. Study participants were continuously enrolled in the Medicaid programs of California, Florida, New York, Ohio, and Pennsylvania. All PLWH enrollees were matched to five randomly sampled HIV-uninfected enrollees on 5-year age group, gender, and state. Adjusted odds ratios (AORs) for incident CRC (adjusted for comorbidity index) and the presence of CRCS (adjusted for comorbidity index and years in the data-set) among PLWH compared to HIV-uninfected enrollees were calculated. PLWH were not more likely to be diagnosed with CRC after adjusting for comorbidity index (unadjusted OR: 1.73, 95% confidence interval [CI]: 1.37–2.19; AOR 1.29; 95% CI: 0.98–1.70). While CRCS rates were low overall, PLWH were more likely to have received CRCS in unadjusted analyses (35.8% vs. 33.7%; OR 1.10, 95% CI: 1.07–1.13). This relationship was reversed after adjusting for comorbidity index and years in the data-set (AOR: 0.80, 95% CI: 0.77–0.83). Limitations of the study include a focus on the Medicaid population, an inability to detect fecal occult blood tests (FOBT), and having half of patients between 50 and 55 years of age. In conclusion, PLWH were not more likely to be diagnosed with CRC, but in adjusted analyses, were less likely to have received CRCS. As we showed a low rate of CRCS overall in this Medicaid population, researchers, clinicians, and policy-makers should improve access to and uptake of CRCS among all Medicaid patients, and particularly among PLWH.  相似文献   
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