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991.

Background  

Presently, health costs associated with nitrate in drinking water are uncertain and not quantified. This limits proper evaluation of current policies and measures for solving or preventing nitrate pollution of drinking water resources. The cost for society associated with nitrate is also relevant for integrated assessment of EU nitrogen policies taking a perspective of welfare optimization. The overarching question is at which nitrogen mitigation level the social cost of measures, including their consequence for availability of food and energy, matches the social benefit of these measures for human health and biodiversity.  相似文献   
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The quadrilobe flap allows the mobilisation of the skin of the upper nose and nasofacial sulcus to the distal nose while avoiding unfavourable tension vectors that would distort the free margin of the ala. We report our experience over the past 3 years in the first case series of quadrilobe flaps for repair of surgical defects on the nose.  相似文献   
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AIMS: Fat-free mass (FFM) is increasingly recognized as a systemic marker of disease severity in chronic organ failure and is an important target for physiologic and pharmacologic interventions to improve functional status. The aim of this study was therefore to evaluate two clinical methods to assess FFM in patients with chronic heart failure (CHF) using deuterium dilution (DEU) as reference and bromide dilution to assess the ratio between intracellular (ICW) and extracellular water (ECW) as potential confounder. METHODS: Body composition was measured with dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA) and DEU in 22 stable patients from our heart failure outpatient clinic and 24 healthy age matched controls. RESULTS: FFM values measured by DXA and DEU in patients (r = 0.92, SEE: 3.1 kg) and controls (r = 0.99, SEE: 1.3 kg) were strongly related. In both patients and controls, the inter method difference increased with higher values of FFM (DXA overestimating DEU). The ICW/ECW ratio was within the normal range and comparable between the groups. In patients, a highly significant correlation coefficient was found (r = 0.93, SEE 2.1 p = 0.01) between total body water (DEU) and height squared/resistance (Ht2/R). On multiple regression next to Ht2/R, body weight was an independent predictor of FFM(DEU) (r = 0.95, SEE 2.5 kg, p<0.001; TBWdeu = 0.528 Ht2/R + (0.182 weight) + 8.277). CONCLUSION: DXA and DEU are appropriate and interchangeable laboratory methods for assessment of FFM in clinically stable heart failure patients, however, overestimation of FFM(DXA) should be considered. BIA is a suitable clinical alternative for diagnostic purposes.  相似文献   
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The purpose of this study was to determine the course of fatigue in patients with breast cancer between 2 cycles of adjuvant chemotherapy, from the day of administration until the day of the next infusion. In a prospective cohort study, a sample of 151 patients with breast cancer receiving adjuvant chemotherapy was recruited from 6 hospitals in mainly the south of the Netherlands. Patients reported their experience of fatigue in a diary, the Shortened Fatigue Questionnaire, on a daily basis between the third and fourth treatment with adjuvant chemotherapy. Patients were treated with either a doxorubicin containing schedule or with cyclophosphamide, methotrexate, and 5-fluorouracil (CMF, 28 days). In the 28-day regimens, infusions were given on day 1 and day 8. The days after completion of the third and the start of the fourth treatment with chemotherapy were statistically analyzed. We tested the hypothesis that the maximum fatigue score occurs in the first 4 days after treatment. The mean age of the sample was 47.2 years (SD = 8.8). Most women (84%) were married or lived together with a partner. The majority (80%) of all patients had been diagnosed with stage II breast cancer. The division between mastectomies (47%) and lumpectomies (52%) was approximately equal. Sixty percent of the patients received radiotherapy before the third treatment with chemotherapy and/or in the period they kept the diary. A chaotic pattern of fatigue between the 2 cycles of chemotherapy emerged. Smooth (splines) curves showed an average highest level of fatigue on day 3 from the start. For the 28-day regimens, another distinct peak was seen around day 11. A relatively larger number of patients experienced peak fatigue levels before day 5. The course of fatigue in the CMF group was significantly different compared with the doxorubicin regimens. The fatigue peak in the CMF group was lower. Women taking cyclophosphamide orally experienced the peak level of fatigue significantly later. Influences of other variables were not observed in any chemotherapy group. Cancer-related fatigue has a chaotic nature. The first days after treatment with chemotherapy are the worst. The type of chemotherapy has a significant impact on the course of fatigue. Improved understanding of the nature and course of fatigue could equip healthcare providers better for informing patients about what they may expect. Future research should include interventions aimed at reducing or coping with fatigue.  相似文献   
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The neurophysiology of the rodent visual system has mainly been investigated by invasive and ex-vivo techniques providing fragmented data. This area of research has been deprived of functional MRI studies based on blood oxygenation level dependent (BOLD) contrast, which allows a whole brain approach with a high spatial and temporal resolution. In the present study, we looked at the neurovascular response properties of the visual system of the pigmented rat, focusing on the visual cortex (VC), the superior colliculus (SC) and the flocculus-paraflocculus of the cerebellum (FL-PFL), using BOLD fMRI under domitor anesthesia. Visual stimulation was performed monocularly or binocularly while flashing light from a strobe unit was presented. For each structure, we assessed the flashing frequency that evoked the optimal BOLD response: Neither the VC nor the FL-PFL displayed frequency dependence during monocular visual stimulation, but were most sensitive to low frequencies (1-5 Hz) when flashing light was provided binocularly. The SC responded optimally to high flashing rates (8-12 Hz) during both monocular and binocular stimulation. The signal intensity changes in the VC and FL-PFL were locked to the stimulation period, whereas the BOLD response in the SC showed a similar onset but a very slow recovery at offset. The VC and FL-PFL, but not the SC, showed signs of binocular competition. The observed correlation between frequency-dependent responses of different visual areas during binocular visual presentation suggests a functional relationship between the VC and FL-PFL rather than between the SC and FL-PFL.  相似文献   
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