The fundamental flexural guided wave (FFGW), as modeled, for example, by the A0 Lamb mode, is a clinically useful indicator of cortical bone thickness. In the work described in this article, we tested so-called multiridge-based analysis, based on the crazy climber algorithm and short-time Fourier transform, for assessment of the FFGW component recorded by a clinical array transducer featuring a limited number of elements. Methods included numerical finite-element simulations and experiments in bone phantoms and human radius specimens (n = 41). The proposed approach enabled extraction of the FFGW component and determination of its group velocity. This group velocity was in good agreement with theoretical predictions and possessed reasonable sensitivity to cortical width (r2 = 0.51, p < 0.001) in the in vitro experiments. It is expected that the proposed approach enables related clinical application. Further work is still needed to analyze in more detail the challenges related to the impact of the overlying soft tissue. 相似文献
Objective: To evaluate the performance of first trimester biochemical markers, pregnancy-associated plasma protein-A (PAPP-A), free beta human chorionic gonadotropin (fβ-hCG), and nuchal translucency (NT) in detection of severe congenital heart defects (CHDs).
Methods: During the study period from 1 January 2008 to 31 December 2011, biochemical markers and NT were measured in 31,144 women as part of voluntary first trimester screening program for Down’s syndrome in Northern Finland. Data for 71 severe CHD cases and 762 controls were obtained from the hospital records and from the National Medical Birth Register, which records the birth of all liveborn and stillborn infants, and from the National Register of Congenital Malformations that receives information about all the CHD cases diagnosed in Finland.
Results: Both PAPP-A and fβ-hCG multiple of median (MoM) values were decreased in all severe CHDs: 0.71 and 0.69 in ventricular septal defects (VSDs), 0.58 and 0.88 in tetralogy of Fallot cases (TOFs), 0.82 and 0.89 in hypoplastic left heart syndromes (HLHSs), and 0.88 and 0.96 in multiple defects, respectively. NT was increased in all study groups except of VSD group. ROC AUC was 0.72 for VSD when combining prior risk with PAPP-A and fβ-hCG. Adding NT did not improve the detection rate. With normal NT but decreased (<0.5 MoM) PAPP-A and fβ-hCG odds ratios for VSD and HLHS were 19.5 and 25.6, respectively.
Conclusions: Maternal serum biochemistry improves the detection of CHDs compared to NT measurement only. In cases with normal NT measurement but low concentrations of both PAPP-A and fβ-hCG, an alert for possible CHD, especially VSD, could be given with thorough examination of fetal heart in later ultrasound scans. 相似文献
This study investigated changes in perceived depression, anxiety and loneliness during a 16-year follow-up among elderly Jyväskylä residents born in 1914-1923. A further concern was with how perceived atmosphere in the formative environment was reflected in depression, anxiety and loneliness in old age. The first phase of the study took place in 1988 when interviews were conducted with 635 persons (241 men and 394 women). Depression and anxiety were assessed using the Finnish modified version of Beck's 13-item depression scale (RBDI), which was completed fully by 74% of the interviewees. Loneliness was assessed with a single four category item. In the second phase of the study in 1996, interviews were conducted with 410 persons, of whom 94% filled the RBDI questionnaire. In the third phase in 2004, the number of interviewees was 220 and the response rate 82%. There were no significant changes in the number of people with depressive symptomatology and anxiety, except in 1996 when the proportion of men with mild and moderate depression almost doubled. The number of men and women who felt lonely increased significantly during the 16-year follow-up. People who said they were lonely also had more depression and anxiety than others. People who had grown up in warm and safe environment were the most balanced mentally. The presence or absence of warmth and safety in the formative environment is reflected in mental well-being even at a very old age. 相似文献
AIM To compare the effects of regular vs low-FODMAP rye bread on irritable bowel syndrome(IBS) symptoms and to study gastrointestinal conditions with Smart Pill?.METHODS Our aim was to evaluate if rye bread low in FODMAPs would cause reduced hydrogen excretion,lower intraluminal pressure,higher colonic p H,different transit times,and fewer IBS symptoms than regular rye bread.The study was a randomized,double-blind,controlled cross-over meal study.Female IBS patients(n = 7) ate study breads at three consecutive meals during one day.The diet was similar for both study periods except for the FODMAP content of the bread consumed during the study day.Intraluminal p H,transit time,and pressure were measured by Smart Pill,an indigestible motility capsule.RESULTS Hydrogen excretion(a marker of colonic fermentation) expressed as area under the curve(AUC)(0-630 min) was [median(range)] 6300(1785-10800) ppm?min for low-FODMAP rye bread and 10 635(4215-13080) ppm?min for regular bread(P = 0.028).Mean scores of gastrointestinal symptoms showed no statistically significant differences but suggested less flatulence after low-FODMAP bread consumption(P = 0.063).Intraluminal pressure correlated significantly with total symptom score after regular rye bread(ρ = 0.786,P = 0.036) and nearly significantly after lowFODMAP bread consumption(ρ = 0.75,P = 0.052).We found no differences in p H,pressure,or transit times between the breads.Gastric residence of Smart Pill was slower than expected.Smart Pill left the stomach in less than 5 h only during one measurement(out of 14 measurements in total) and therefore did not follow on par with the rye bread bolus.CONCLUSION Low-FODMAP rye bread reduced colonic fermentation vs regular rye bread.No difference was found in median values of intraluminal conditions of the gastrointestinal tract. 相似文献
OBJECTIVE: To investigate the value of serum antitissue transglutaminase IgA antibodies (IgA-TTG) and IgA antiendomysial antibodies (IgA-EMA) in the diagnosis of coeliac disease in cohorts from different geographical areas in Europe. The setting allowed a further comparison between the antibody results and the conventional small-intestinal histology. METHODS: A total of 144 cases with coeliac disease [median age 19.5 years (range 0.9-81.4)], and 127 disease controls [median age 29.2 years (range 0.5-79.0)], were recruited, on the basis of biopsy, from 13 centres in nine countries. All biopsy specimens were re-evaluated and classified blindly a second time by two investigators. IgA-TTG were determined by ELISA with human recombinant antigen and IgA-EMA by an immunofluorescence test with human umbilical cord as antigen. RESULTS: The quality of the biopsy specimens was not acceptable in 29 (10.7%) of 271 cases and a reliable judgement could not be made, mainly due to poor orientation of the samples. The primary clinical diagnosis and the second classification of the biopsy specimens were divergent in nine cases, and one patient was initially enrolled in the wrong group. Thus, 126 coeliac patients and 106 controls, verified by biopsy, remained for final analysis. The sensitivity of IgA-TTG was 94% and IgA-EMA 89%, the specificity was 99% and 98%, respectively. CONCLUSIONS: Serum IgA-TTG measurement is effective and at least as good as IgA-EMA in the identification of coeliac disease. Due to a high percentage of poor histological specimens, the diagnosis of coeliac disease should not depend only on biopsy, but in addition the clinical picture and serology should be considered. 相似文献
Background: Delayed electrical activity necessary for re‐entrant ventricular tachycardia (VT) is detectable noninvasively with high resolution techniques. We compared high resolution signalaveraged analysis of magnetocardiography (MCG), body surface potential mapping (BSPM), and orthogonal three‐lead ECG (SA‐ECG) in the identification of patients prone to VT after myocardial infarction (Ml). Methods: Patients with remote myocardial infarction and cardiac dysfunction were studied, 22 with (VT group) and 22 without VT (control group). MCG with seven channels and BSPM with 63 and SA‐ECG with three orthogonal leads were registered. After signal‐averaging and highpass filtering, three time domain analysis (TDA) parameters describing late electrical activity were computed: QRS duration (QRSd), root mean square amplitude (RMS) of the last 40 ms of QRS, and the duration of the low‐amplitude QRS end (LAS). Results: All parameters by each method were significantly different between the patients’groups. For example, LAS parameter in MCG was 59 (SD 22) ms in the VT group vs. 37 (SD 13) ms in controls (P < 0.001), 77 (SD 22) ms vs. 56 (SD 19) ms in BSPM (P = 0.002), and 60 (SD 24) ms vs. 39 (SD 22) ms in SA‐ECG (P = 0.005). The combination of LAS parameter in MCG and SA‐ECG resulted in improved performance in comparison to any single parameter with 95% sensitivity and 68% specificity. Conclusions: All three high resolution methods identified VT propensity among post‐Mi patients with cardiac dysfunction and between‐method differences were small. Information in MCG and SA‐ECG may be complementary and their combination could be of value in postinfarction arrhythmia risk assessment. A.N.E. 2002;7(4):389–398 相似文献
OBJECTIVE: The combination of small birth size and the Pro12Pro variant of the peroxisome proliferator-activated receptor-gamma 2 (PPAR-gamma 2) gene has been shown to be associated with insulin resistance, which is linked to hypertension. We examined whether the association between small body size at birth and adult blood pressure is modulated by PPAR-gamma 2 gene polymorphism, and whether the use of any class of antihypertensive medication is related to birth size. DESIGN AND METHODS: A total of 500 subjects from an original epidemiological cohort of 7086 men and women aged 65-75 years attended a clinical study. Two hundred and eight of them (73 men and 135 women) were taking antihypertensive medication and are included in this study. The Pro12Ala polymorphism of the PPAR-gamma 2 gene was determined using the polymerase chain reaction single-strand conformation polymorphism method. RESULTS AND CONCLUSIONS: Hypertensive subjects with low birth weight or short length at birth and the Pro12Pro variant had raised systolic blood pressure. We suggest that insulin resistance enhances the regulatory responses of the renin-angiotensin system, leading to raised blood pressure levels. Those hypertensive subjects who had small birth size and the Pro12Pro variant tended to use angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers (ACEI/ARB). This could be because insulin resistance interacts with the renin-angiotensin system in ways that make ACEI/ARB an effective therapy. Alternative explanations include more severe and treatment resistant hypertension, leading to application of ACEI/ARB, or co-morbid conditions, such as myocardial infarction and type 2 diabetes, known to be linked to low birth weight. 相似文献