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71.
72.
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings. 相似文献
73.
Joanna Rees Simone Radavelli Bagatini Johnny Lo Jonathan M. Hodgson Claus T. Christophersen Robin M. Daly Dianna J. Magliano Jonathan E. Shaw Marc Sim Catherine P. Bondonno Lauren C. Blekkenhorst Joanne M. Dickson Joshua R. Lewis Amanda Devine 《Nutrients》2021,13(5)
Increasing prevalence of mental health disorders within the Australian population is a serious public health issue. Adequate intake of fruits and vegetables (FV), dietary fibre (DF) and resistant starch (RS) is associated with better mental and physical health. Few longitudinal studies exist exploring the temporal relationship. Using a validated food frequency questionnaire, we examined baseline FV intakes of 5845 Australian adults from the AusDiab study and estimated food group-derived DF and RS using data from the literature. Perceived mental health was assessed at baseline and 5 year follow up using SF-36 mental component summary scores (MCS). We conducted baseline cross-sectional analysis and prospective analysis of baseline dietary intake with perceived mental health at 5 years. Higher baseline FV and FV-derived DF and RS intakes were associated with better 5 year MCS (p < 0.001). A higher FV intake (754 g/d vs. 251 g/d, Q4 vs. Q1) at baseline had 41% lower odds (OR = 0.59: 95% CI 0.46–0.75) of MCS below population average (<47) at 5 year follow up. Findings were similar for FV-derived DF and RS. An inverse association was observed with discretionary food-derived DF and RS. This demonstrates the association between higher intakes of FV and FV-derived DF and RS with better 5 year mental health outcomes. Further RCTs are necessary to understand mechanisms that underlie this association including elucidation of causal effects. 相似文献
74.
Anne Daly Wolfgang Hgler Nicola Crabtree Nick Shaw Sharon Evans Alex Pinto Richard Jackson Catherine Ashmore Júlio C. Rocha Boyd J. Strauss Gisela Wilcox William D. Fraser Jonathan C. Y. Tang Anita MacDonald 《Nutrients》2021,13(6)
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs. 相似文献
75.
76.
Nicole E. Sharp MD FACS Darren B. Sachs DO Nicole M. Melchior DO Philip Albaneze MD FACS Salvatore Nardello DO Elin R. Sigurdson MD PhD FACS Mengying Deng MMath Allison A. Aggon DO FACOS John M. Daly MD FACS Richard J. Bleicher MD FACS 《The breast journal》2021,27(4):335-344
Prospective trials demonstrate that sentinel node (SN) biopsy after neo-adjuvant chemotherapy (NACT) has a significant false-negative rate (FNR) when only 1 or 2 SNs are removed. It is unknown whether this increased FNR correlates with an elevated risk of recurrence. Tumor Registry data at an NCI-Designated Comprehensive Cancer Center were reviewed from 2004 to 2018 for patients having a negative SN biopsy after NACT. Among 190 patients with histologically negative nodes after NACT having 1 (n = 42), 2 (n = 46), and ≥3 (n = 102) SNs, axillary recurrences occurred in 7.14%, 0%, and 1.96% (p = 0.09), breast recurrences occurred in 2.38%, 6.52%, and 0.98% (p = 0.12), and distance recurrences occurred in 16.67%, 8.70%, and 7.84% (p = 0.27), respectively. Time to first recurrence did not differ by SN count (p = 0.41). After adjustment for age, race, clinical stage, and receptor status, there were no differences in the rates of axillary (p = 0.26), breast (p = 0.44), or distance recurrence (p = 0.24) by numbers of SNs harvested. Median follow-up was 46.8 months. Despite higher post-NACT FNRs reported in randomized trials for patients having <3 sentinel nodes, recurrence rates were not significantly different for 1 versus 2 versus ≥3 SNs. This suggests that patients having 1 or 2 post-NACT SNs identified may not necessitate axillary dissection. 相似文献
77.
William C. Daly Paul K.J. Han Matthew Hayn Stephen T. Ryan Moritz H. Hansen Joshua P. Linscott Quoc-Dien Trinh Jesse D. Sammon 《Urologic oncology》2021,39(3):192.e15-192.e20
Introduction and objectiveResearch on the utility of meditative and mind-body (MB) practices has increased dramatically in the last two decades and both have been suggested as useful adjuncts in coping with stressors associated with cancer survivorship. There exists little data on use among genitourinary (GU) cancer survivors. This study seeks to describe meditative and MB utilization among GU cancer survivors.MethodsAnalysis of data from the 2012 and 2017 National Health Interview Survey was conducted. Patients aged 40 and older reporting a history of any cancer diagnosis (including 3 GU cancers) were included in the analysis. We explored questions about meditative and MB practices in the past 12 months. Complex Samples Logistic regression was performed to compare the relationship between cancer status and use of these practices.ResultsSelf-reported meditative practices were more prevalent in 2017 (17%) than in 2012 (5%). Patients who self-reported a cancer diagnosis of any kind were significantly more likely to utilize meditative practices. Patients with kidney cancer were significantly more likely to meditate and trended towards higher MB utilization. In contrast, bladder cancer patients were less likely to meditate and use MB practices. Increases in meditation were greater than those seen for MB in all groups.ConclusionsMeditative and MB practices increased in prevalence between 2012 and 2017 with notable heterogeneity between cancer types. Given the potential benefit, more broad incorporation into survivorship programs may be warranted. Future work should explore the significance of this heterogeneity and the utility of these practices to patients with urologic malignancy. 相似文献
78.
Rabea Asleh Hilmi Alnsasra Amir Lerman Alexandros Briasoulis Naveen L. Pereira Brooks S. Edwards Takumi Toya John M. Stulak Alfredo L. Clavell Richard C. Daly Sudhir S. Kushwaha 《American journal of transplantation》2021,21(2):626-635
We have previously described the use of sirolimus (SRL) as primary immunosuppression following heart transplantation (HT). The advantages of this approach include attenuation of cardiac allograft vasculopathy (CAV), improvement in glomerular filtration rate (GFR), and reduced malignancy. However, in some patients SRL may cause significant proteinuria. We sought to investigate the prognostic value of proteinuria after conversion to SRL. CAV progression and adverse clinical events were studied. CAV progression was assessed by measuring the Δ change in plaque volume (PV) and plaque index (PI) per year using coronary intravascular ultrasound. Proteinuria was defined as Δ urine protein ≥300 mg/24 h at 1 year after conversion to SRL. Overall, 137 patients were analyzed (26% with proteinuria). Patients with proteinuria had significantly lower GFR (P = .005) but similar GFR during follow-up. Delta PV (P < .001) and Δ PI (P = .001) were significantly higher among patients with proteinuria after adjustment for baseline characteristics. Multivariate Cox regression analysis showed higher all-cause mortality (hazard ratio 3.8; P = .01) with proteinuria but similar risk of CAV-related events (P = .61). Our results indicate that proteinuria is a marker of baseline renal dysfunction, and that HT recipients who develop proteinuria after conversion to SRL have less attenuation of CAV progression and higher mortality risk. 相似文献
79.
M Delannes N Daly J Bonnet J Sabatier M Trémoulet 《Neuro-Chirurgie》1990,36(3):167-74; discussion 174-5
Radiosurgery is a technique which provides a single high dose of radiation very precisely to an intracranial lesion. The volume of tissue treated is small enough to avoid undue biological damage. This treatment requires very sophisticated apparatus and often considerable modifications in the treatment apparatus. The authors have closen to elaborate a system which makes it possible to deliver conventional fractionated irradiation, using a non-invasive stereotactic head frame called "Laitinen stereo-adapter". By fractionating the dose, most benign or low-grade malignant brain tumours can be treated, whatever their volume. The stereo-adapter and the target localization process are described. It can be used with C.T. scanning, angiography or M.R.I. The treatment apparatus is a linear accelerator delivering a 10 M.V. photon beam and treatment is made in the precise positioning of the target localization. The geometrical accuracy of the repeated mountings was studied in a preliminary study, showing a mean discrepancy of less than 1 mm in the three space planes. The geometrical accuracy of the radiation treatment was also studied on a phantom and the precision evaluated at less than 1 mm. The addition of extra collimators with a precollimation system decreased the lateral penumbra to 2-3 mm. Careful dosimetry was performed for each collimator. The use of non-coplanar arcs makes it possible to obtain a steep dose fall off outside the target volume. The dose planning calculations were compared to photodensitometry and thermoluminescent measurements, showing a good correlation. Each technical point will be discussed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
80.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献