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41.
The purpose of the present study was to reduce background tracks by removing a given surface layer of the 250 μm thick lexan polycarbonate foils before exposure to alpha particles. Ethylenediamine solution was used for taking layers from the surface of the foils.  相似文献   
42.
Twenty solvent-exposed workers, most of them painters, had been diagnosed as cases of toxic encephalopathy in 1978/79. Two years later they were re-examined with an extensive battery of neuropsychological tests. Their performance was unchanged on retesting. We have now compared their test results with those of non-exposed control subjects. Previous impressions of significant intellectual impairment in the solvent-exposed patients could not be confirmed when the influence of age, education, and intelligence was taken into consideration. The present group with presumed toxic encephalopathy is assumed to be representative of other patients who were similarly diagnosed in our department. The presently reanalyzed cases had been diagnosed as brain damaged and reported as such in the literature. Thus, they may have contributed to the formation of the concept of the "chronic painters' syndrome" with dementia.  相似文献   
43.
The sniff magnitude test (SMT) is a reliable and rapid clinical test of olfactory function that is minimally dependent on cognitive and linguistic abilities. In this study, we compared performance on the SMT and University of Pennsylvania Smell Identification Test (UPSIT) in samples of children and nonnative English speakers. Previous research has shown that these populations perform poorly on the UPSIT as compared with young, healthy U.S. adults. Such performance differences may reflect variations in memory/cognition and language/culture rather than olfactory abilities. The UPSIT scores of children and of Indian and Chinese graduate students were found to be lower than those of young U.S. adults. By contrast, these groups did not perform more poorly than U.S. adults did on the SMT. The results are consistent with findings from our studies, with the elderly showing that performance on the UPSIT, but not the SMT, is significantly correlated with measures of memory, language and other cognitive abilities. The findings highlight the utility of the SMT when evaluating the olfactory ability of the very young, older adults and people with diverse linguistic and cultural backgrounds.  相似文献   
44.
Hitherto, various critics have claimed that the most commonly used measure for daily hassles is confounded with psychological well-being in both content and format. In order to circumvent such contamination, the Survey of Recent Life Experiences (SRLE) was developed by Kohn and MacDonald (1992). In the present study, the SRLE was psychometrically evaluated within a general sample of the Dutch population. Confirmatory factor analysis showed that, with the exception of one item, the original six-factor structure was strongly replicated. For five of six factors, internal consistency reliabilities proved satisfactory. It is argued that the rather low internal consistency reliability of the sixth factor may be improved if additional items are subjoined. In addition, yielded relationships between the SRLE and other variables were in accordance with previous research. It is therefore argued that the results are in support of cross-cultural construct validity of the SRLE. Future use within other Western European societies is recommended.  相似文献   
45.
Review of the mutagenicity of ethylene oxide   总被引:4,自引:0,他引:4  
Ethylene oxide has been shown to be an effective mutagen in a variety of organisms ranging from bacteria to mammalian cells. There is also an association between ethylene oxide exposure and human somatic cell cytogenetic damage. Furthermore, ethylene oxide has been shown to alkylate protein and DNA at exposure levels that have been encountered occupationally. Ethylene oxide is not only effective at producing somatic cell mutations but also at inducing genetic damage in germ cells. While it is clear that ethylene oxide is a germ cell mutagen in whole mammals, the mechanism(s) by which it produces genetic lesions in germ cells is uncertain.  相似文献   
46.
Evaluated the utility of neuropsychological testing in predictingacademic outcome in children 1 year following traumatic braininjury (TBI). Fifty-one schoolage children who were admittedto hospital after TBI were assessed with a battery of neuropsychologicalmeasures at 3 months postinjury. Academic achievement was assessedat 3 and 12 months postinjury. The neuropsychological batteryincluded intelligence testing and measures of memory, learning,and speed of information processing. Academic outcome was assessedin terms of post-TBI changes in reading, spelling, and arithmetic;changes in teacher ratings of school performance; and changein school placement. According to logistic regression analysis,change in placement from regular to special education at 1-yearpost-TBI was predicted by injury severity and by neuropsychologicalperformance at 3 months post-TBI. Findings suggest that neuropsychologicaltesting is useful in identifying children with special educationalneeds subsequent to TBI.  相似文献   
47.
Examined the utility of a new parent-report measure designedspecifically for pediatric inpatients, the Behavioral Upsetin Medical Patients-Revised (BUMP-R). The BUMP-R was administeredto 151 mothers of hospitalized children ages 4–12 yearsthe day following the child's hospital admission. The BUMP-Rdemonstrated good internal consistency and a factor analysisrevealed four factors identified as negativity/agitation, amiability,dysphoria, and noncom-pliance. Children exhibiting behavioraldistress at home were more likely to experience adjustment problemsupon hospitalization. Demographic and illness-related variableswere not substantial risk factors for hospital adjustment difficulties.  相似文献   
48.
Zusammenfassung Anhand einer prospektiven, auslesefreien Serie von 22 Patienten mit perforierten Ulcera im Gastroduodenalbereich verweisen wir auf die begrenzte diagnostische Aussagekraft einfacher anamnestischer, klinischer und radiologischer Daten. Lediglich bei acht Patienten (36%) ergaben sich wesentliche Indizien aus Krankengeschichte und Aufnahmebefund. Bei 16 Patienten (73%) verriet die Thoraxübersichtsaufnahme durch Nachweis einer subphrenischen Luftsichel eine Perforation im Magen-Darm-Trakt. Die Ultraschalluntersuchung wird als bedeutungsvolle Ergänzungsmethode vor allem in der diagnostischen Abklärung radiologisch negativer Ulcusperforationen vorgestellt und diskutiert. Dabei werden die sonographisch faßbare flüssigkeitsbedingte Magendistension sowie das Magenwandödem als unspezifische Kriterien gewertet. Der Objektivierung einer pathologischen Magenkokarde kommt bei gleichzeitigem Nachweis freier Luft und/oder extraluminärer Ingesta sowie freier echoloser Transsudatflüssigkeit pathognomonische Beweiskraft zu. Selbige Ultraschallkriterien erlaubten im einschlägigen Krankengut bei 16 Patienten (73%) eine definitive Diagnose und erfaßte 4 Patienten mit negativem Röntgen. Die kombinierte Analyse radiologischer und sonographischer Befunde führte somit bei 20 Patienten (91 %) unverzüglich zur korrekten Diagnose.
Perforated peptic ulcer: Diagnosis and assessment by sonography
Summary In a prospective unselected series of 22 patients with perforated gastroduodenal ulcers the diagnostic efficacy of clinical and radiologic data was modest. In eight patients only (36%), clinical data yielded sufficient evidence; in 16 patients (73%), plain X-ray demonstrated subphrenic gas. Sonography was proven to be a major advance, especially rewarding in the diagnosis of perforations with negative plain X-ray. Gastric distention and stomach wall edema are unspecifc sonographic criteria, whereas objectivation of a pathologic stomach cockade in the presence of free gas, extraluminary ingesta or echofree fluid in the peritoneal cavity are pathognomonic data. These criteria yielded a definite diagnosis in 16 patients (73%) including four patients with negative X-ray. The combined analysis of radiologic and sonographic findings yielded an immediate correct diagnosis in 20 patients (91%).
  相似文献   
49.
Diabetes is the seventh leading cause of death in United States. Dietary intake and behaviors are essential components of diabetes management. Growing evidence suggests dietary components beyond carbohydrates may critically impact glycemic control. Assessment tools on mobile platforms have the ability to capture multiple aspects of dietary behavior in real-time throughout the day to inform and improve diabetes management and insulin dosing. The objective of this narrative review was to summarize evidence related to dietary behaviors and composition to inform a mobile image-based dietary assessment tool for managing glycemic control of both diabetes types (type 1 and type 2 diabetes). This review investigated the following topics amongst those with diabetes: (1) the role of time of eating occasion on indicators of glycemic control; and (2) the role of macronutrient composition of meals on indicators of glycemic control. A search for articles published after 2000 was completed in PubMed with the following sets of keywords “diabetes/diabetes management/diabetes prevention/diabetes risk”, “dietary behavior/eating patterns/temporal/meal timing/meal frequency”, and “macronutrient composition/glycemic index”. Results showed eating behaviors and meal macronutrient composition may affect glycemic control. Specifically, breakfast skipping, late eating and frequent meal consumption might be associated with poor glycemic control while macronutrient composition and order of the meal could also affect glycemic control. These factors should be considered in designing a dietary assessment tool, which may optimize diabetes management to reduce the burden of this disease.  相似文献   
50.
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