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71.
Serological assays capable of measuring antibody responses induced by previous infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been critical tools in the response to the COVID-19 pandemic. In this study, we use bead-based multiplex assays to measure IgG and IgA antibodies and IgG avidity to five SARS-CoV-2 antigens (Spike (S), receptor-binding domain (RBD), Nucleocapsid (N), S subunit 2, and Membrane-Envelope fusion (ME)). These assays were performed in several cohorts of healthcare workers and nursing home residents, who were followed for up to eleven months after SARS-CoV-2 infection or up to six months after vaccination. Our results show distinct kinetic patterns of antibody quantity (IgG and IgA) and avidity. While IgG and IgA antibody levels waned over time, with IgA antibody levels waning more rapidly, avidity increased with time after infection or vaccination. These contrasting kinetic patterns allow for the estimation of time since previous SARS-CoV-2 infection. Including avidity measurements in addition to antibody levels in a classification algorithm for estimating time since infection led to a substantial improvement in accuracy, from 62% to 78%. The inclusion of antibody avidity in panels of serological assays can yield valuable information for improving serosurveillance during SARS-CoV-2 epidemics.  相似文献   
72.

Purpose

A prospective, single-center, single-arm feasibility study evaluated procedural and short-term performance of the Advance Enforcer 35 focal-force percutaneous transluminal angioplasty (PTA) balloon catheter in treating stenoses of mature native arteriovenous (AV) hemodialysis access circuits.

Materials and Methods

Twenty-eight patients undergoing treatment for stenosis of a mature native AV hemodialysis access circuit were enrolled at a single institution. Angiographic assessments of the study lesion were required at baseline and after the procedure. Adjunctive procedures for significant residual stenosis were permitted, and patients had clinical and imaging follow-up for as long as 6 months.

Results

Treatment with the study balloon was effective in reducing the average percent diameter stenosis of the treated lesion from 66.3% (range, 43.8%–93.3%) before the procedure to 23.7% (range, ?6.7% to 51.4%) after the procedure. The average inflation pressure required was 12.3 atm. Only 1 patient required an adjunctive procedure, and all patients could resume normal dialysis following the study procedure. At 3 months, 62.0% of study lesions remained patent, and the 6-month patency rate was 25.1%. Two adverse events associated with the study procedure were reported: access-site hematoma and forearm pain (3.6% each).

Conclusions

The results demonstrate safety of the study balloon in treating AV access stenosis. Nominal-diameter angioplasty was achieved at relatively low pressure in most study patients without the use of adjunctive procedures, and resumption of normal dialysis was achieved for all patients.  相似文献   
73.
Many functional diseases are related to dysautonomia, and heart rate variability has been used to assess dysautonomia. However, heart rate variability has not been studied in Spleen-Qi deficiency syndrome (SQDS). Healthy volunteers (n = 37) and patients with SQDS (n = 67), recruited from the Clinic of the State University of Ecatepec Valley were included in the study. Outcome measures were average heart rate, standard deviation of the normal-to-normal heartbeat intervals, low frequency (LF), high frequency (HF) power, and the LF/HF ratio. Also, intestinal peristalsis, gastrointestinal symptoms (GSs), fatigue, and level of attention were measured. Standard deviation of the normal-to-normal heartbeat intervals (17 ± 2.3%) and HF (14 ± 3.1%) were lower in SQDS patients (17 ± 1.3%) than in healthy volunteers. SQDS patients had higher heart rate, LF power, LF/HF ratio, and fatigue scores (9.6 ± 1.12%, 16 ± 2.1%, 22 ± 3.8%, and 21 ± 4.1%). The fatigue correlated positively with the LF/HF ratio and negatively with HF power. The SQDS group had lower concentration performance (16.2 ± 1.9%) in the d2 test. The intestinal peristalsis showed a reduction (15 ± 1.3%) as compared with control. GS score and peristalsis correlated negatively with HF. Our results suggest that the pathology of SDQS could be associated with a low vagal tone which causes a decrease in peristalsis, increased fatigue, reduced attention, and appearance of GSs.  相似文献   
74.
Background: A key feature of health professionals’ training, irrespective of discipline, is the acquisition and application of clinical and communication skills. Despite this, little is known about the potential role of patient feedback on this process. This systematic review aimed to answer the question: How does feedback from patients impact upon healthcare student clinical skill development and learning?

Design: Systematic review of published literature.

Methods: Electronic databases were searched for studies that explored the effects of patient feedback on student learning and were published before March 2016. Eligible articles underwent methodological evaluation using the McMaster University Critical Evaluation Forms and data extraction.

Results: A total of 237 articles were retrieved following searches of electronic databases and hand searches of reference lists. Twelve (7 quantitative, 2 qualitative, 3 mixed methods) studies met the inclusion criteria. Eleven studies reported that patient feedback improved students’ clinical skills.

Conclusion: Minimal research has explored the impact of patient feedback on student learning. The research to date suggests that direct feedback from patients may be beneficial for the development of students’ communication and clinical skills; however, the wide variety of evaluation methods and the lack of validated tools for patients to provide feedback suggest that further exploration is warranted.  相似文献   
75.
Diagnostic reliability of indexations of peak exercise ST segment depression (DeltaST) for heart rate reserve (HRi) or chronotropic reserve (CR) to identify significant coronary artery disease (CAD) by cycle-ergometer exercise testing has not been evaluated previously. Exercise testing by upright cycle-ergometer (25 W/3 min) were performed in consecutive patients in primary prevention with history of exercise-related chest discomfort and cardiovascular risk factors, or with overt peripheral artery disease, with or type-2 diabetes associated with two or more additional cardiovascular risk factors. Coronary angiography was performed after the test to assess significant CAD. Three different criteria for definition of inducible myocardial ischemia were tested versus significant CAD: peak DeltaST>or=100 microV, ST/HRi>1.69 microV/bpm or ST/CR>1.76 microV/%. Diagnostic accuracy vs. CAD of DeltaST>or=100 microV, of ST/HRi>1.69 microV/bpm, and of ST/CR>1.76 microV/% were 78%, 72%, and 89% respectively; sensitivity and specificity of the three criteria were 91% and 50%, 84% and 43%, 88% and 93%, respectively. Abnormal ST/CR predicted CAD independent of risk factors, pre-test probability, and more strongly than DeltaST. Combination of ST/HRi and ST/CR criteria did not improve CAD prediction. In conclusions, in clinical setting in patients in primary prevention but with moderate-to-high pre-test probability of CAD, exercise testing by cycle-ergometry and use of ST/CR>1.76 microV/% showed elevated sensitivity and specificity, and the best accuracy for diagnosis of significant CAD.  相似文献   
76.
77.
Our findings show a high rate of loss to follow-up in HIV-positive teenagers compared with adults. Of concern is the fact that this group also have high rates of sexually transmitted infections, unprotected sex and pregnancy. There is an urgent need to examine the reasons for this and adopt strategies to minimize risk-taking behaviour and to improve access to appropriate healthcare.  相似文献   
78.
Digestive Diseases and Sciences - Acute kidney injury is seen in approximately 30% of patients with severe alcohol-associated hepatitis (AH) and is associated with increased mortality. Controversy...  相似文献   
79.
80.
BackgroundThe prevalence of targeted and serendipitous treatment for, and associated recovery from, urinary tract infection (UTI) in pre-school children is unknown.AimTo determine the frequency and suspicion of UTI in children who are acutely ill, along with details of antibiotic prescribing, its appropriateness, and whether that appropriateness impacted on symptom improvement and recovery.MethodSystematic urine sampling from children aged <5years presenting in primary care with acute illness with culture in NHS laboratories.ResultsOf 6079 children’s urine samples, 339 (5.6%) met laboratory criteria for UTI and 162 (47.9%) were prescribed antibiotics at the initial consultation. In total, 576/7101 (8.1%) children were suspected of having a UTI prior to urine sampling, including 107 of the 338 with a UTI (clinician sensitivity 31.7%). Children with a laboratory-diagnosed UTI were more likely to be prescribed antibiotics when UTI was clinically suspected than when it was not (86.0% versus 30.3%, P<0.001). Of 231 children with unsuspected UTI, 70 (30.3%) received serendipitous antibiotics (that is, antibiotics prescribed for a different reason). Overall, 176 (52.1%) children with confirmed UTI did not receive any initial antibiotic. Organism sensitivity to the prescribed antibiotic was higher when UTI was suspected than when treated serendipitously (77.1% versus 26.0%; P<0.001). Children with UTI prescribed appropriate antibiotics at the initial consultation improved a little sooner than those with a UTI who were not prescribed appropriate antibiotics initially (3.5 days versus 4.0 days; P = 0.005).ConclusionOver half of children with UTI on culture were not prescribed antibiotics at first presentation. Serendipitous UTI treatment was relatively common, but often inappropriate to the organism’s sensitivity. Methods for improved targeting of antibiotic treatment in children who are acutely unwell are urgently needed.  相似文献   
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