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1.
In a review of 305 consecutive patients who had undergone truncal vagotomy and gastrojejunostomy for duodenal ulceration 5-15 (mean 10.5) years before, symptomatic and metabolic sequelae were related to a dietary survey in 109 patients. The incidence of post vagotomy symptoms was related to the incidence of weight loss and reduced dietary energy intake. The dietary survey did not show any trends in the incidence of weight loss since operation. Biochemical steatorrhoea occurred in 48% of 96 patients, but this was not related to dietary fat intake, or to weight loss unless diarrhoea was also present. Anaemia was noted in 13% of patients, but the incidence was not related to dietary survey, age, symptoms or post-vagotomy gastric acid output.  相似文献   
2.
Di-isononyl phthalate (DINP) is a high molecular weight general purpose plasticizer used principally in the manufacture of flexible polyvinyl chloride (PVC) articles. DINP metabolites can be measured in biological media such as blood and urine. However, measurement of a substance in the blood or urine does not by itself mean that the chemical causes or is associated with adverse health outcomes. This is particularly pertinent given the advances in modern analytical techniques whereby ever diminishing trace amounts of substances can be detected. Therefore, it is a scientific necessity that risk assessors understand the relationship of biomonitoring data to estimation of exposure so that appropriate comparisons can be made to the no observed adverse effects levels (NOAELs) or other points of departure from toxicological studies in animals. In this paper, estimates of daily DINP intake are calculated for various population segments based on urinary biomonitoring data and are compared to estimates of exposure based on indirect methods and to health-based exposure guidance values. In general, intake estimates converge on a mean of 1–2 μg/kg/day regardless of source of exposure or population cluster; a value 2-orders of magnitude lower than health-based exposure guidance values, ranging from 120 to 290 μg/kg/day, which have been established by regulatory authorities and other authoritative bodies as representing acceptable levels.  相似文献   
3.
Locust bean gum (LBG) is a galactomannan polysaccharide used as thickener in infant formulas with the therapeutic aim to treat uncomplicated gastroesophageal reflux (GER). Since its use in young infants below 12 weeks of age is not explicitly covered by the current scientific concept of the derivation of health based guidance values, the present integrated safety review aimed to compile all the relevant preclinical toxicological studies and to combine them with substantial evidence gathered from the clinical paediatric use as part of the weight of evidence supporting the safety in young infants below 12 weeks of age. LBG was demonstrated to have very low toxicity in preclinical studies mainly resulting from its indigestible nature leading to negligible systemic bioavailability and only possibly influencing tolerance. A standard therapeutic level of 0.5 g/100 mL in thickened infant formula is shown to confer a sufficiently protective Margin of Safety. LBG was not associated with any adverse toxic or nutritional effects in healthy term infants, while there are limited case-reports of possible adverse effects in preterms receiving the thickener inappropriately. Altogether, it can be concluded that LBG is safe for its intended therapeutic use in term-born infants to treat uncomplicated regurgitation from birth onwards.  相似文献   
4.
A Conference was held in Paris in 2006 to review the safety and benefits arising from the replacement of sucrose with the intense sweetener aspartame. The intakes of aspartame are only about 10% of the acceptable daily intake, even by high consumers, so that the safety margin is about 3 orders of magnitude. The safety of aspartame was confirmed in the EFSA Opinion of a recent controversial rodent cancer bioassay. There is increasing evidence that even modest reductions in the intake of calories can reduce the risk factors associated with a number of diseases, such as diabetes and cardiovascular disease. A key issue addressed at the conference was whether the replacement of sucrose with aspartame could result in a prolonged decrease in calorie intake that was of similar magnitude to that necessary to produce a health benefit. A recent meta-analysis of published data showed that an adequate, prolonged weight reduction could be achieved with aspartame. It was recognised that risk assessment alone gave an unbalanced impression to regulators and consumers, and that in the future quantitative risk-benefit analyses should be able to provide more comprehensive advice.  相似文献   
5.
Contamination and health risk hazards of organophosphorus pesticides residues in vegetables were studied. Ethyl-chlorpyrifos, observed at an average level of 0.211 ± 0.010 mg kg−1 in 42% of tomato, 0.096 ± 0.035 mg kg−1 in 10% of eggplant and 0.021 ± 0.013 mg kg−1 in 16% of pepper was below the 0.5 mg kg−1 MRL. Dichlorvos was the most frequently detected residue in all the samples analyzed. Levels of malathion in tomatoes (0.120 ± 0.101 mg kg−1) and pepper (0.143 ± 0.042 mg kg−1) exceeded the MRL of 0.1 mg kg−1. Health risks were found to be associated with methyl-chlorpyrifos, ethyl-chlorpyrifos, and omethioate in tomatoes and methyl-chlorpyrifos, ethyl-chlorpyrifos, dichlorvos, monocrotophos and omethioate in eggplant. Routine monitoring of these pollutants in food items is required to prevent, control and reduce the pollution and to minimize health risks.  相似文献   
6.
Autism Spectrum Disorders (ASD) are associated with abnormalities in face memory, which evidence suggests has a protracted development through adolescence. The development of face memory in people with and without ASD, from 9 to 29 years old, was examined using the Cambridge Face Memory Test (CFMT). Results indicate that the developmental improvement evident from adolescence to adulthood typically was not apparent in individuals with ASD. While children and adolescents with ASD performed similarly to typically developing individuals comparable in age and IQ, adults with ASD displayed limitations on the CFMT. The pattern of performance was constant across conditions despite differences in the timing of the presentation and delay. This atypical development in ASD is consistent with the view that the processing of complex visual stimuli continues to develop through adolescence, along with the function and structure of the temporal lobes, but that this process is disrupted in ASD. This result underscores the importance of characterizing adolescent development for understanding ASD, and suggests additional opportunities for intervention.  相似文献   
7.
The benchmark dose (BMD) approach is being increasingly used in the area of food risk assessment because it offers several advantages compared to the conventional no-observed-adverse-effect-level approach. The aim of this work was to check the applicability of the BMD approach on toxicity data available from pesticides, mycotoxins and natural toxins.  相似文献   
8.
Rev7™ is an indigestible gum polymer used for the manufacturing of chewing gum. It allows for the formulation of chewing gum with low adhesion; thus can be readily removed from surfaces such as sidewalks, clothing, carpets and furniture. In a toxicological safety assessment, Rev7™ was found to be non-mutagenic in the AMES assay. The highest concentration tested in a mouse lymphoma thymidine kinase locus gene mutation assay induced a slight but biologically relevant increase in mutations under non-metabolic activation conditions after 24 h. Because of this finding, a mouse micronucleus assay was performed, and the test article was found to be negative for inducing chromosomal damage. A 28-day repeated oral toxicity study resulted in a NOAEL of 80,000 ppm; the highest concentration tested. Rev7™ was found to be free from contaminants such as heavy metals, monomers, and solvents. Lastly, Rev7™ did not demonstrate skin-sensitizing properties in the murine local lymph node assay.  相似文献   
9.

Introduction

Atlantodental interval (ADI), basion-dental interval (BDI) and the thickness of prevertebral soft tissue (TOPST) measured in lateral cervical radiographs were reported to be useful indicators and indirect signs of underlying cervical spine injuries. However, cervical computed tomography (MDCT) is the first method of imaging used in all trauma patients and upper normal limits (UNLs) of cervical distances according to age and sex are undetermined. Therefore, we aimed to calculate these metrics.

Methods

500 adult trauma patients with cervical MDCT at the time of admission were retrospectively selected. ADI, BDI, and TOPSTs were measured by two blinded researchers.

Results

488 cervical spine CT scans were reported to be normal and 12 has pathological findings. Mean ADI, BDI and TOPST of C1, C2, C6 and C7 were statistically significantly wider in males. In females, ADI and BDI were significantly narrower with the increase in age. In males, only ADI was significantly narrower, and TOPST of C6 and C7 vertebra were significantly wider with the increase in age. We found the optimal UNLs as follows: ADI 2.5 mm, BDI 8.5 mm, C1 6.5 mm, C2 5.7 mm, C3 6.3 mm (6 mm for C1–3 for practical purposes), C4 11.7 and C5–7 17 mm.

Discussion

We believe that the increase in distances with age may be affected by the height losses of discs and vertebral bodies, formation of anterior osteophytes and regional kyphosis by age. Those results were compatible with the previous reports.  相似文献   
10.
Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline such as a reference dose (RfD) or tolerable daily intake (TDI). BE values can be used as a screening tool for the evaluation of population-based biomonitoring data in the context of existing risk assessments. This study reviews available health based risk assessments and exposure guidance values for di-isononyl phthalate (DINP) from Health Canada, the United States Consumer Product Safety Commission (US CPSC), and the European Food Safety Authority (EFSA). Controlled dosing data reporting the urinary excretion fractions of major DINP metabolites following administration of labeled DINP are reviewed, and BE values corresponding to the available exposure guidance values are derived assuming chronic, steady-state intake and excretion at those exposure values. The BE values range from 1500 to 3600μg/L (1900-4600μg/g creatinine) based on the sum of three oxidative metabolites. Sources of uncertainty relating to both the basis for the BE values and their use in evaluation of biomonitoring data, including the transience of the biomarkers relative to exposure frequency, are discussed. The BE values derived here can be used as screening tools for evaluation of population biomonitoring data for DINP in the context of existing risk assessments and can assist in prioritization of the potential need for additional risk assessment efforts for DINP relative to other chemicals.  相似文献   
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