The results of the monitoring of characteristics of digital receivers for X-ray images by using enterprise (VNIIMT) reference standard 01-22-04

Described are the results of testing of methods of the new 01-22-04 standard designed for monitoring the image-quality parameters of digital X-ray converter-receivers (made alongside with tests of digital X-ray diagnostic units ProScan-7000 and ProScan-2000).     

Neutron personnel dosimetry intercomparison studies at the Oak Ridge National Laboratory: a summary (1981-1986)

To provide an opportunity for dosimetrists to test and calibrate their neutron personnel monitoring systems, the staff of the Dosimetry Applications Research (DOSAR) Facility at the Oak Ridge National Laboratory (ORNL) has conducted personnel dosimetry intercomparison studies (PDIS) periodically since 1974. During these studies, personnel dosimeters are mailed to ORNL, exposed to low-level (less than 15 mSv) neutron dose equivalents in a variety of mixed-radiation fields, and then returned to the participants for evaluation. These intercomparisons have provided more data on neutron dosimeter performance than any other periodic test program conducted to date. This report presents a summary and analysis of about 3450 neutron dose equivalent measurements reported for PDIS 7 through 12 (1981-1986) with emphasis on low dose equivalent sensitivity, accuracy and precision, and performance relative to accreditation standards for the basic types of personnel dosimetry systems. Relationships of the PDIS results to occupational neutron monitoring, accreditation testing, and methods to improve personnel neutron dosimetry performance are also discussed.     

Assessing the genotoxicity of chronic environmental irradiation by using mitochondrial DNA heteroplasmy in the bank vole (Clethrionomys glareolus) at Chornobyl,Ukraine

This study was designed to investigate whether or not chronic exposure to Chornobyl radiation poses a molecular genetic risk to mammals by examining a relatively rapidly evolving genetic system, mitochondrial DNA (mtDNA). More mtDNA mutations (approximately 19%) and an increase in mtDNA heteroplasmy (approximately 5%) occurred in the cytochrome b gene of an exposed mother-embryo set when compared to a relatively unexposed mother-embryo set. However, this increase was not statistically significant (p > 0.05). Our results, in conjunction with previous molecular genetic research on small mammals from Chornobyl, suggest that chronic exposure to environmental ionizing radiation does not increase the number of nucleotide substitutions, as predicted by studies using acute or subacute exposures. Thus, cumulative models of radiation risk would not appear to follow simple linear functions derived from high doses and dose rates. The equivocal nature of research regarding the effects of the Chornobyl accident indicates that future research is warranted such that models of chronic environmental exposure can be developed or refined. Although additional study is required to properly validate mtDNA heteroplasmy as a useful effect biomarker, examination of these data does not indicate that a significant risk to mtDNA exists in native rodents chronically exposed to both internal and external radiation.     

A system of ultrasonic guidance for use in studying the brain (studies on models)

Ultrasonic echo-impulse devices for brain monitoring, widely used in clinical medicine, permit to achieve a diagnostical information about the location of volume pathological formations in brain and characteristics of intracranial hemodynamics during short-time researches. According to model testing, the developed system of electron search and guidance of ultrasonic rays to intracranial structure elements for monitoring of spinal fluid haemodynamic characteristics in cranial cavity can be used for search, guidance and retention of the chosen direction of ultrasonic sounding for the period of physiological information reading.     

Hanford radiation study III: a cohort study of the cancer risks from radiation to workers at Hanford (1944-77 deaths) by the method of regression models in life-tables.

This paper reports on results from the study initiated by Mancuso into the health risks from low-level radiation in workers engaged in plutonium manufacture at Hanford Works, Washington State, USA, and attempts to answer criticisms of previous reports by an in-depth study. Previous reports have aroused much controversy because the reported risk per unit radiation dose for cancers of radiosensitive tissues was much greater than the risk generally accepted on the basis of other studies and widely used in setting safety levels for exposure to low-level radiation. The method of regression models in life-tables isolates the effect of radiation after statistically controlling for a wide range of possible interfering factors. Like the risk of lung cancer for uranium miners the dose-response relation showed a significant downward curve at about 10 rem. There may, therefore, be better agreement with other studies, conduct at higher doses, than is widely assumed. The findings on cancer latency (of about 25 years) and the effect of exposure age (increasing age increases the risk) are in general agreement with other studies. An unexplained finding is a significantly higher dose for all workers who developed cancers in tissues that are supposed to have low sensitivity to cancer induction by radiation.     

分析全麻诱导中应用舒芬太尼对心血管系统的影响

目的:探讨舒芬太尼在全麻诱导中对心血管系统的影响。方法:将70例将行全麻诱导患者纳入研究,随机分为实验组(舒芬太尼组)、对照组(芬太尼组)各35例,在诱导前、后以及插管时、插管后分别监测并记录心率、血压。结果:诱导前、后的心率,对照组均快于实验组,两组比较具有统计学意义(P<0.05),但插管时和插管后3min,对照组心率明显快于实验组,两组差异性显著(P<0.01)。诱导后的收缩压和舒张压,实验组均低于对照组,两组比较差异具有统计学意义(P<0.05);插管时、插管后3min的收缩压和舒张压,对照组明显高于试验组,两组比较具有显著性差异(P<0.01);而诱导前的收缩压和舒张压,两组比较差异性不显著(P>0.05)。结论:舒芬太尼可有效抑制全麻时心血管系统反应,适合临床应用。     

Determination of the feasibility of using a portable X-ray fluorescence (XRF) analyzer in the field for measurement of lead content of sieved soil

Soil samples collected in housing areas with potential lead contamination generally are analyzed with flame atomic absorption spectrometry (FAAS) or other laboratory methods. Previous work indicates that field-portable X-ray fluorescence (XRF) analysis is capable of detecting soil lead levels comparable to those detected by FAAS in samples sieved to less than 125 microm in a laboratory. A considerable savings, both economical and in laboratory reporting time, would occur if a practical field method could be developed that does not require laboratory digestion and analysis. The XRF method also would provide immediate results that would facilitate the provision of information to residents and other interested parties more quickly than is possible with conventional laboratory methods. The goal of the study reported here was to determine the practicality of using the field-portable XRF analyzer for analysis of lead in soil samples that were sieved in the field. The practicality of using the XRF was determined by the amount of time it took to prepare and analyze the samples in the field and by the ease with which the procedure could be accomplished on site. Another objective of the study was to determine the effects of moisture on the process of sieving the soil. Seventy-eight samples were collected from 30 locations near 10 houses and were prepared and analyzed at the locations where they were collected. Mean soil lead concentrations by XRF were 816 ppm before drying and 817 ppm after drying, and by laboratory FAAS were 1,042 ppm. Correlation of field-portable XRF and FAAS results was excellent for samples sieved to less than 125 microm, with R2 values of .9902 and .992 before and after drying, respectively. The saturation ranged from 10 percent to 90 percent. At 65 percent saturation or higher, it was not feasible to sieve the soil in the field without a thorough drying step, since the soil would not pass through the sieve. Therefore the field method with sieving was not practical when the soil was 65 percent or more saturated unless a time-consuming drying process was included.     

2012-2014年宜昌市结核病防治医防合作实施效果分析

目的分析2012-2014年宜昌市结核病医防合作实施效果,为今后结核病防治提供参考和建议。方法收集并分析2012-2014年宜昌市肺结核患者发现、初诊查痰、转诊追踪、耐药发现等指标。结果实施医防合作3年来,肺结核患者发现、治疗、管理各项指标均保持在较高水平,涂阴培养率从1.93%提高到73.95%,培养阳性患者数逐年增加;耐药筛查率从12.05%提升至96.97%,2014年耐药患者发现数是2012年的3.56倍。结论宜昌市结核病医防合作取得明显成效,但仍需提升定点医院诊疗水平。     

A review and analysis of the clinical and cost-effectiveness studies of comprehensive health promotion and disease management programs at the worksite: 1995-1998 update (IV)

The fourth in a series of critical reviews, this study examines the clinical and cost outcome evaluations of 10 worksite health promotion programs that were comprehensive, multifactorial, and directed at risk management. The studies, conducted between 1994 and 1998, indicate favorable clinical and cost outcomes and suggest characteristics of worksite interventions that may be critical for effectiveness.     

Suitability of the pH buffers 3-[N-N-bis(hydroxyethyl)amino]-2-hydroxypropanesulfonic acid and N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid for in vitro copper toxicity studies

The influence of the zwitterionic (ampholytic) pH buffers, 3-[N-N-bis(hydroxyethyl)amino]-2-hydroxypropanesulfonic acid (DIPSO, 10 mM) and N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES, 25 mM), on the toxicity of copper(II) to the marine dinoflagellate, Amphidinium carterae, was investigated. For this purpose, DIPSO or HEPES buffered complete ESAW (enrichment solution artificial seawater) growth media as well as simplified (enrichment solution deficient) buffered media were assayed in the toxicity tests, at pH 8.0. Similar assays were performed in unbuffered ESAW medium. Toxicity evaluation was based on growth changes, EC₅₀ (effective concentration of labile copper that reduces growth rate by 50%) and esterase activity. In addition to biological parameters, electrochemical behavior of the buffers in the presence of copper(II) was used to interpret the results. Neither of the buffers were toxic to A. carterae. HEPES increased copper toxicity (synergistic effect) while DIPSO diminished it (strong antagonistic effect). HEPES does not significantly complex copper(II) and this effect was possibly due to change in kinetics of metal binding to the organisms due to its surfactant properties at 25 mM. DIPSO is a strong copper(II) complexing agent (average conditional stability constant, log K=7.3, pH 8.0, 25°C). These results suggest that DIPSO may substitute EDTA in culture media with the advantage of simultaneously buffering changes in pH and metallic cations.     

Infant feeding method and obesity: body mass index and dual-energy X-ray absorptiometry measurements at 9-10 y of age from the Avon Longitudinal Study of Parents and Children (ALSPAC)

BACKGROUND: Previous studies reported inconsistent associations between breastfeeding and body mass index (BMI; in kg/m2). Associations with body fatness are unknown. OBJECTIVE: We investigated the association of breastfeeding with fatness measured by dual-energy X-ray absorptiometry. DESIGN: The prospective cohort study involved 4325 singletons with measurements at 9-10 y of age to assess the main outcomes of BMI and total and trunk fat masses. RESULTS: Prevalence of any breastfeeding was 82%. In crude analyses, breastfeeding was inversely associated with total fat mass [% change per category increase (4 categories)] in breastfeeding duration (-4.4%; 95% CI: -3.1%, -5.6%) and trunk fat mass (-0.5%; 95% CI: -1.1%, 0.1%); the odds of adiposity were measured by total [odds ratio (OR): 0.81; 95% CI: 0.75, 0.88] and trunk (OR: 0.78; 95% CI: 0.71, 0.84) fat masses in the top decile. In adjusted models, the inverse association of breastfeeding with mean total fat mass was attenuated by 59% (% change per category increase in breastfeeding duration: -1.8%; 95% CI: -0.5%, -3.1%), but associations with trunk fat mass (% change per category increase in breastfeeding duration: -0.6%; 95% CI: 0.0%, -1.3%) and the ORs for total (0.76; 95% CI: 0.69, 0.84) and trunk (0.74; 95% CI: 0.67, 0.81) fat masses in the top decile were little altered. Children breastfed >or=6 mo had the lowest odds of total fat mass in the top decile (OR: 0.45; 95% CI: 0.33, 0.62). In multivariate models, there was little evidence that breastfeeding was associated with mean or threshold values of BMI. CONCLUSIONS: The protective association of breastfeeding with mean total fat mass was attenuated somewhat after adjustment for confounders, which indicated that confounding may explain this association. Breastfeeding may protect against obesity if maintained for >or=6 mo.