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Segmental aortic wall stiffness was calculated from intravascular ultrasound images and intravascular pressures in six pigs at normal and subnormal aortic pressures (21 sequences of pressures and areas before and after boli of intravenous nitroglycerin). The wall stiffness was expressed as the pressure-strain elastic modulus (Ep). The Ep was calculated from the formula: Ep = delta PR delta R-1 (P, pressure; R, radius) in two different ways. First from maximal and minimal values of pressure and area. Second as the slope of linear regression line of delta PR as a function of delta R from 29 simultaneous recorded pressures and images. The average Ep value for all sequences in the different segments was 0.58 +/- 0.55 10(5) Pa (Method 1) and 0.50 +/- 0.40 10(5) Pa (Method 2). Ep increased with the distance from the heart at normal aortic pressures. At subnormal aortic pressures after intravenous nitroglycerin this relationship was not so evident. At subnormal aortic pressures the calculated Ep values were significantly reduced in the lower half of the abdominal aorta. The phase lag, i.e. hysteresis, between pressure and diameter was demonstrated. Our study shows the applicability of intravascular ultrasound as a tool to evaluate arterial wall stiffness.  相似文献   
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An epidemiological investigation was conducted to identify risk factors related to hygiene and husbandry practices which determine the introduction of Campylobacter spp. into broiler chicken flocks. All 176 broiler farms in an area in southeastern Norway participated in the study. Each farm was represented by one flock selected at random during a one-year period. The flocks were examined for campylobacter colonization at slaughter, and the flock managers were subsequently interviewed about hygiene and husbandry practices. Campylobacter spp. were recovered from 32 (18%) of the flocks. The proportion of colonized flocks varied geographically and seasonally with a peak in the autumn. The following variables were found to be independently associated with an increased risk of campylobacter colonization using logistic regression analysis: (i) feeding the broilers undisinfected water (odds ratio (OR) = 3.42, P = 0.045), (ii) tending other poultry prior to entering the broiler house (OR = 6.43, P = 0.007), (iii) tending pigs before entering the house (OR = 4.86, P = 0.037), (iv) geographic region (Hedmark versus Ostfold county) (OR = 2.91, P = 0.023, (v) season (autumn versus other seasons) (OR = 3.43; P = 0.008). Presence of rats on the farm was associated with an increased risk, but this factor did not reach statistical significance (OR = 3.96, P = 0.083). Preventive measures should include disinfection of drinking water and strict hygienic routines when the farm workers enter the rearing room. The results indicate that disinfection of drinking water is the preventive measure most likely to have the greatest impact on the prevalence of campylobacter among broiler chicken flocks in the study area (population attributable fraction = 0.53).  相似文献   
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Cerebral MRI was performed at 1.5 T in 27 infants with birth weight below 1500 grams at 1 year of corrected age. The images were compared to those reported on normal development at the same age. On T1 weighted images, 20 (74.1%) of the 27 infants showed myelin deposition different from what has been reported to be normal. Areas most affected were the central occipital white matter and the centrum semiovale. Both correspond to watershed areas known to be at risk for periventricular leukomalacia in preterm infants. T2-weighted images showed delayed myelination in the same areas as described for T1. In addition, two infants showed delayed myelination in the central occipital white matter and one in the centrum semiovale. Patchy focal abnormalities involving the white matter were seen in seven (25.9%) infants. Mild cerebral atrophy, mainly of the cortex was found in 10 (37.0%) infants. Irregular shape of the lateral ventricles, especially of the occipital horns was present in 12 infants (44.4%). 11 of these infants also had deviating changes in myelination. Only 2 infants (7.4%) had a normal MRI examination. Follow-up MRI examinations are needed to determine whether the high percentage of changes in myelination represent delayed development or brain damage in preterm infants.  相似文献   
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Prevalence of faecal incontinence among women with urinary incontinence   总被引:4,自引:0,他引:4  
Four hundred and sixty-five women attending a urodynamic clinic were interviewed, and completed a detailed bowel questionnaire, about their urinary and bowel symptoms. All the women underwent video-cystourethrography with pressure and flow studies. The reported incidence of faecal incontinence was 15.3% (   n = 71  ) on direct questioning and 26% 0(  n = 121  ) on the postal questionnaire. Faecal incontinence was more common in women with a urodynamic diagnosis of detrusor instability (30'%1 (   n = 26  )) than among women diagnosed as having genuine stress incontinence (21% (   n = 38  )). Denervation and myogenic injuries sustained during childbirth have been suggested as a common cause for genuine stress and faecal incontinence, but there may be an alternative mechanism to explain why women with detrusor instability suffer from faecal incontinence.  相似文献   
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Health concerns as a result of harmful UV-rays drive the development of UV-sensors of different kinds. In this research, a UV-responsive smart textile is produced by inkjet printing and UV-LED curing of a specifically designed photochromic ink on PET fabric. This paper focuses on tuning and characterizing the colour performance of a photochromic dye embedded in a UV-curable ink resin. The influence of industrial fabrication parameters on the crosslinking density of the UV-resin and hence on the colour kinetics is investigated. A lower crosslinking density of the UV-resin increases the kinetic switching speed of the photochromic dye molecules upon isomerization. By introducing an extended kinetic model, which defines rate constants kcolouration, kdecay and kdecolouration, the colour performance of photochromic textiles can be predicted. Fabrication parameters present a flexible and fast alternative to polymer conjugation to control kinetics of photochromic dyes in a resin. In particular, industrial fabrication parameters during printing and curing of the photochromic ink are used to set the colour yield, colouration/decolouration rates and the durability, which are important characteristics towards the development of a UV-sensor for smart textile applications.

Tuned performance of an inkjet-printed and UV-LED cured smart textile UV-sensor based on a photochromic dye using fabrication parameters.  相似文献   
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Background

Thyroid cancer is the most common malignancy of the endocrine system, representing 3.8% of all new cancer cases in the United States and is the ninth most common cancer overall. The American Cancer Society estimates that 62,450 people in the United States will be diagnosed with thyroid cancer in 2015, and 1950 deaths will result from the disease.

Objective

To review the current approach to the diagnosis and treatment of patients with thyroid cancer.

Discussion

Over the past 3 decades, there has been a dramatic increase in the number of people diagnosed with thyroid cancer, which may be attributable to the wide use of imaging studies, including ultrasounds, computed tomography, magnetic resonance imaging, and positron emission tomography scans that incidentally detect thyroid nodules. Thyroid cancer is divided into several main types, with papillary thyroid cancer being the most common. The treatment options for patients with thyroid cancer include the surgical removal of the entire thyroid gland (total thyroidectomy), radioactive iodine therapy, and molecular-targeted therapies with tyrosine kinase inhibitors. This article summarizes the diagnosis and treatment of thyroid cancer, with recommendations from the American Thyroid Association regarding thyroid nodules and differentiated thyroid cancer. Recently approved drugs and treatment trends are also explored.

Conclusion

The prognosis and treatment of thyroid cancer depend on the tumor type and its stage at the time of diagnosis. Many thyroid cancers remain stable, microscopic, and indolent. The increasing treatment options for patients with thyroid cancer, including therapies that were recently approved by the US Food and Drug Administration, have kept the mortality rate from this malignancy low, despite the increase in its incidence. Early diagnosis and appropriate treatment can improve prognosis and reduce mortality.  相似文献   
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