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991.
BACKGROUND: Rapid image acquisition after cessation of exercise is essential for accurate stress echocardiography. Recently, a prototype matrix-array transducer has been developed that allows simultaneous acquisition of 2 imaging planes (biplane [BP] imaging). METHODS: In all, 19 healthy volunteers underwent 2 separate stress echocardiographic studies. Images were acquired in traditional 2-dimensional or BP format pre-exercise and postexercise. RESULTS: Total image acquisition time for 2-dimensional stress echocardiography was 38 +/- 8 seconds versus 29 +/- 8 seconds for BP imaging (P <.05). Heart rates were acquired closer to age-predicted maximum with BP imaging in the apical 3- and 2-chamber and parasternal long- and short-axis views (82%, 75%, 70%, 70% for BP vs 76%, 72%, 68%, 66% for 2-dimensional, respectively). CONCLUSION: BP imaging using a recently developed matrix-array probe allows more rapid imaging postexercise, resulting in acquisition of poststress images at higher heart rates without compromising image quality.  相似文献   
992.

Purpose

Exercise is associated with a lower risk of acquiring chronic diseases in adulthood. The aim of this study was to investigate the association of regular soccer practice with health-related behaviours among male adolescents.

Methods

This cross-sectional study included 739 male adolescents aged 14–18 years from the city of Aracaju, in north-eastern Brazil. Information about soccer practice and health-related behaviours (smoking, alcohol use, dietary habits, physical activity, and sedentary behaviour) was collected based on a self-administered questionnaire. Logistic regression analysis was used to estimate odds ratios (ORs) and confidence intervals of 95 %.

Results

Approximately 35.0 % of adolescents practiced soccer for three or more days during the week. Adolescents aged 14–16 years, adolescents at intermediate and high socio-economic levels, those who were physically active, and those who showed satisfactory consumption of fruits and vegetables were more likely to practice soccer for three or more days during the week.

Conclusions

These findings demonstrate that soccer practice should be encouraged among male adolescents during their leisure time because it is a low-cost and enjoyable practice that can increase physical activity levels in school populations and is associated with other healthy behaviours.
  相似文献   
993.
Purpose Assessment of body size at autopsy is important for interpreting organ weight measurements and in some cases body identification. The reliability of post-mortem body size measurements, the causes for perturbations in these measurements from their corresponding pre-mortem values, and the impact of such perturbations on heart weight interpretation have not been fully explored. Methods Autopsy body length and weight measurements and pre-mortem height and body weight measurements were compared in 132 autopsies. Clinical records were evaluated for peripheral edema and serum albumin levels. Causes of death, body cavity fluid collections, and heart weights were obtained from the autopsy reports. A subset of patients underwent quantitative post-mortem computed tomography assessment of anasarca. Results At autopsy, body weight differed from the pre-mortem value by 11 ± 1 %, compared with ?0.2 ± 0.3 % for body length (P < 0.0001). The percent change in body weight at autopsy correlated with the presence of peripheral edema (14 ± 2 % vs. 7 ± 2 %, P = 0.01), serum albumin < 3.0 g/dL (16 ± 2 % vs. 7 ± 2 %, P = 0.001), and the degree of anasarca (P = 0.01). In 4 % of autopsies, heart weights were abnormal based on the pre-mortem body weight, but would be classified as normal based on the elevated post-mortem body weight. Conclusions At autopsy, body weight is a less reliable parameter than body length in correlating with the corresponding pre-mortem measurement. Autopsy body weights are elevated in part due to peripheral edema/anasarca. Alterations in body weight at autopsy can confound the interpretation of organ weight measurements.  相似文献   
994.
995.
996.
The investigation of laser-tissue interaction is crucial for diagnostics and therapeutics. In particular, the estimation of tissue optical properties allows developing predictive models for defining organ-specific treatment planning tool. With regard to laser ablation (LA), optical properties are among the main responsible for the therapy efficacy, as they globally affect the heating process of the tissue, due to its capability to absorb and scatter laser energy. The recent introduction of LA for pancreatic tumor treatment in clinical studies has fostered the need to assess the laser-pancreas interaction and hence to find its optical properties in the wavelength of interest. This work aims at estimating optical properties (i.e., absorption, μ a , scattering, μ s , anisotropy, g, coefficients) of neuroendocrine pancreas tumor at 1064 nm. Experiments were performed using two popular sample storage methods; the optical properties of frozen and paraffin-embedded neuroendocrine tumor of the pancreas are estimated by employing a double-integrating-sphere system and inverse Monte Carlo algorithm. Results show that paraffin-embedded tissue is characterized by absorption and scattering coefficients significantly higher than frozen samples (μ a of 56 cm?1 vs 0.9 cm?1, μ s of 539 cm?1 vs 130 cm?1, respectively). Simulations show that such different optical features strongly influence the pancreas temperature distribution during LA. This result may affect the prediction of therapeutic outcome. Therefore, the choice of the appropriate preparation technique of samples for optical property estimation is crucial for the performances of the mathematical models which predict LA thermal outcome on the tissue and lead the selection of optimal LA settings.  相似文献   
997.
Oral mucositis (OM) and radiodermatitis (RD) are serious side effects of radiotherapy (RT), often leading to its suspension, need for analgesics, and enteral/parenteral nutrition. Laser therapy is becoming a recommended treatment option. This prospective study aimed at demonstrating the beneficial effect of class IV laser therapy (HPLT) on RT-induced OM, an off-label use of HPLT to treat RD in breast cancer patients. Fifty-three cancer patients, during/after RT and/or chemotherapy (CT), affected by OM, were treated with HPLT during four consecutive days (970?±?15 nm, 5 W (50 %), 35–6000 Hz, 240 s). Assessment of OM (Grading Objective Scale, WHO-SCALE), pain (visual analogue scale, VAS), functional ability, subjective parameters, and site/severity of OM were recorded over time. Similarly, 27 breast cancer patients affected by RD were treated by HPLT and monitored over time for grade, discomfort, itching, and bleeding. Progressive improvement of WHO-SCALE from day 7 on, and of VAS from day 2 on (p?<?0.000) was registered. All patients’ functional capacity improved on day 4 (p?<?0.05). All subjective parameters improved on day 14 (p?<?0.001) except for voice, which improved on day 21 (p?<?0.000). Ulcerations’ dimension and erythema’s severity significantly decreased in all sites examined (p?<?0.05). Similarly, HPLT proved to be beneficial in managing RD for all the parameters considered (p?<?0.002). Regardless of OM grade/site and of kind/site of tumor, HPLT proved to be effective in healing OM as well as RD. In both cases, effective treatment can improve life quality through a safe, easy, innovative approach. Therefore, HPLT may become an integral part of everyday practice in the management of RT adverse effects.  相似文献   
998.

Introduction

In renal cell carcinoma (RCC), lymph node status at preoperative imaging is affected by a non-negligible false-positive rate. We aimed to investigate which factors are related to a concordance between clinical suspicion and pathological confirmation of lymph node invasion (LNI).

Methods

At a single tertiary care institution, 2954 RCC patients underwent either partial or radical nephrectomy. For the aim of the study, only clinically positive lymph node cases were included (cN1). Statistical analyses assessed the concordance between preoperative and pathological nodal status.

Results

Preoperative axial CT scans revealed 424 (14.4 %) patients showing at least one enlarged lymph node suspected for LNI (cN1). All lymphadenopathies were removed at surgery, and LNI was pathologically confirmed (pN1) in 122 patients (28.8 %). When focusing the analyses on clinical characteristics (variables known before surgery), metastases at diagnosis [OR 3.0 (95 %1.9–4.8), p < 0.001] and tumor size [OR 1.1 (95 % 1.1–1.2), p < 0.001] were the two most informative predictors of concordance between clinical and pathological nodal status. Concordance was also more likely in patients with papillary type II tumors (55.6 %) relative to papillary type I (38.1 %), clear cell (27.7 %) and chromophobe (8.3 %) tumors. At multivariable analyses, none of the considered blood markers resulted to be independently associated with LNI.

Conclusions

Roughly 70 % of patients showing a suspected lymph node preoperatively do not show LNI at the final pathological report. Among patients with clinically positive nodes, clinical tumor size and metastases at diagnosis represent the most informative and independent predictors of confirmed LNI at final pathology.
  相似文献   
999.
1000.

Purpose

Sympathetic nervous system (SNS) hyperactivity is a salient characteristic of chronic heart failure (HF) and contributes to the progression of the disease. Iodine-123 meta-iodobenzylguanidine (123I-mIBG) imaging has been successfully used to assess cardiac SNS activity in HF patients and to predict prognosis. Importantly, SNS hyperactivity characterizes also physiological ageing, and there is conflicting evidence on cardiac 123I-mIBG uptake in healthy elderly subjects compared to adults. However, little data are available on the impact of ageing on cardiac sympathetic nerve activity assessed by 123I-mIBG scintigraphy, in patients with HF.

Methods and results

We studied 180 HF patients (age?=?66.1?±?10.5 years [yrs]), left ventricular ejection fraction (LVEF?=?30.6?±?6.3 %) undergoing cardiac 123I-mIBG imaging. Early and late heart to mediastinum (H/M) ratios and washout rate were calculated in all patients. Demographic, clinical, and echocardiographic data were also collected. Our study population consisted of 53 patients aged >75 years (age?=?77.7?±?4.0 year), 67 patients aged 62–72 years (age?=?67.9?±?3.2 years) and 60 patients aged ≤61 year (age?=?53.9?±?5.6 years). In elderly patients, both early and late H/M ratios were significantly lower compared to younger patients (p?<?0.05). By multivariate analysis, H/M ratios (both early and late) and washout rate were significantly correlated with LVEF and age.

Conclusions

Our data indicate that, in a population of HF patients, there is an independent age-related effect on cardiac SNS innervation assessed by 123I-mIBG imaging. This finding suggests that cardiac 123I-mIBG uptake in patients with HF might be affected by patient age.
  相似文献   
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