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1.
Percutaneous absorption of N,N-dimethylformamide in humans   总被引:3,自引:0,他引:3  
Summary Skin penetration fo N,N-dimethylformamide (DMF) liquid or vapour was studied in volunteers. Exposure to liquid DMF was performed in two ways: in a dipping experiment, one hand was dipped up to the wrist in DMF for 2–20 min, while in a patch experiment, 2 mmol DMF was applied to the skin and allowed to be absorbed completely. The period of exposure to DMF vapour (50 mg · m–3) was 4 h. The DMF metabolites N-hydroxymethyl-N-methylformamide (MF), N-hydroxymethylformamide (F), and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) were monitored in the urine. Liquid DMF was absorbed through the skin at a rate of 9.4 mg · cm–2 · h–1. Percutaneous absorption of DMF vapour depended strongly on ambient temperature and humidity and accounted for 13%–36% of totally excreted MF. The results suggest that skin absorption of liquid DMF is likely to contribute to occupational exposure substantially more than penetration of DMF vapour. The yield of metabolites after transdermal DMF absorption was only half of that seen after pulmonary absorption. Elimination of MF and F but not that of AMCC was delayed, which supports the contention that AMCC should be used instead of MF as the most suitable biomarker of DMF in cases where percutaneous intake can occur.  相似文献   

2.
Summary This article reports results regarding two different physiological aspects of 2,5-hexanedione (2,5-HD). The first is the relationship between free 2,5-HD (the fraction of real 2,5-HD) and total 2,5-HD (2,5-HD obtained from acid hydrolysis) in urine and blood of workers exposed ton-hexane. The second part of the study is an attempt to clarify physiological excretion of 2,5-HD in subjects not occupationally exposed ton-hexane. The concentration of free 2,5-HD in urine of workers exposed ton-hexane is about 8% of total urinary 2,5-HD. In blood, free 2,5-HD is about 50% of the total. The serum concentration range of total and free 2,5-HD in workers from whom blood was taken was 33–418 g/l and 14–283 g/l respectively. In subjects not exposed ton-hexane, urinary concentration of 2,5-HD ranged between 0.17 and 0.98 mg/1, the urinary excretion rate between 0.23 and 0.57g/min, and renal clearance between 14 and 66 ml/min. The blood concentration of 2,5-HD in nonexposed subjects was 6–30g/1. Fluctuations typical of a circadian rhythm were not observed for 2,5-HD in blood or urine. We think that 2,5-HD is mainly a product of intermediate metabolism in the human body. Only a minimal part could derive fromn-hexane as a ubiquitous micropollutant.  相似文献   

3.
A comparison of the mating behavior patterns of several macaque species reveals that the mating behavior of Macaca arctoidesexhibits several unique features. The laboratory groups of stumptail monkeys observed had exceptionally long single-mount copulations characterized by a large number of pelvic thrusts, a slow thrusting rate, and an unusually salient male orgasmic pattern (characterized by body rigidity followed by body spasms and a typical facial expression and vocalization). The frequency with which the copulation culminates in ejaculation is unusually high, and copulating stumptails generally manifest tieing in a genital lock after ejaculation. This research was supported in part by the Interdisciplinary Training Program, Langley Porter Neuropsychiatric Institute, University of California, San Francisco; by United States Public Health Service Training Grant No. 5-T1-MH-7082 from the National Institute of Public Health; and by Grant No. GS-31943X from the National Science Foundation to Dr. S. L. Washburn of the University of California at Berkeley, given for Primate Studies and Human Evolution.This paper was given as one part of the presentation prepared for the symposium Male and Female Sexual Behavior in Primate Societies, Fourth International Congress of Primatology, Portland, Oregon, August 1972. The first part was published as Male-Female, Female-Female, and Male-Male Sexual Behavior in the Stumptail Monkey, with Special Attention to the Female Orgasm,Archives of Sexual Behavior 3: 95–116, 1974.  相似文献   

4.
Absorption,metabolism and elimination of N,N-dimethylformamide in humans   总被引:4,自引:0,他引:4  
Summary Excretion of N,N-dimethylformamide (DMF) and DMF metabolites N-hydroxymethyl-N-methylformamide (MF), N-hydroxymethyl-formamide (F) and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) has been monitored in the urine of volunteers during and after their 8-h exposure to DMF vapour at a concentration of 10, 30 and 60 mg · m–3. The pulmonary ventilation in these experiments was typically about 101 · min–1 and the retention in the respiratory tract was 90%. After exposure to 30 mg DMF · m–3, the yield of compound determined in the urine represented 0.3% (DMF), 22.3% (MF), 13.2% (F) and 13.4% (AMCC) of the dose absorbed via the respiratory tract. The excretion curves of the particular compounds attained their maximum 6–8h (DMF), 6–8h (MF), 8–14h (F) and 24–34h (AMCC) after the start of the exposure. The half-times of excretion were approximately 2, 4, 7 and 23 h respectively. In contrast to slow elimination of AMCC after exposure to DMF, AMCC was eliminated rapidly after AMCC intake. This discrepancy could be explained by rate-limiting reversible protein binding of a reactive metabolic intermediate of DMF, possibly methylisocyanate.  相似文献   

5.
Contemporary realities demand that child and youth care managers cast off their traditional avoidance of all things financial. This article offers a jargon-free list of twelve financial rules for thriving in turbulent times. Grounded in a concept of client-centered, results-based agency performance, rules include promoting an entrepreneurial spirit throughout the organization, destroying the taboo on open discussion of financial matters, slashing program development time, and spending lavishly on recruitment and universal staff training.  相似文献   

6.
Conclusion The in vitro recording of spontaneous contractions was selected as a neuromuscular screening method for in vivo exposure to pollutants. The rate of contraction was determined by interval histogram measurements. The method was assessed for effects of age, sex, pH, Ca++ concentration, temperature, and circadian rhythm. Male rats were shown to develop a slower rate of contraction with age. The rate of contraction was temperature and pH dependent. An effect was demonstrated for in vivo exposure to Baygon and Carbaryl at a level which did not produce overt symptoms.  相似文献   

7.
Summary A new specific and sensitive method for the urinary determination of 4,4-methylene-bis-(2-chloroaniline) (MOCA), a known carcinogen in rats, mice and dogs, has been developed. After a brief study on rats to determine some peculiarities in MOCA urinary excretion, this method was used to assess occupational exposure in French industrial firms. Both the manufacture of MOCA and its use as a curing agent in the production of polyurethane elastomers were surveyed. MOCA excretion levels were distributed from non-detectable (<0.5 g/l) up to 1600 g/l. Concentrations of N-acetyl metabolites, when present, were largely lower than MOCA levels. The results seemed to reflect workers' overall exposure fairly. Preventive measures following analytical determinations often led to an obvious lowering of excretion levels.  相似文献   

8.
The Obstacles to Return-to-Work Questionnaire (ORQ) was developed and evaluated. A total of 154 patients with chronic musculoskeletal pain and prolonged work disability participated in the study. Factor analyses reduced the ORQ to 55 items grouped into 9 subscales. The subscales were named Depression, Pain intensity, Difficulties at work return, Physical workload and harmfulness, Social support at work, Worry due to sick leave, Work satisfaction, Family situation and support, and Perceived prognosis of work return. The subscales showed satisfactory reliability. In order to determine predictive validity a discriminant analysis was conducted with sick leave 9 months after assessment as the outcome. This analysis indicated that the scales Perceived prognosis of work return, Social support at work, Physical workload and harmfulness, Depression, and Pain intensity could significantly predict sick leave and correctly classified 79% of the patients. The Multidimensional Pain Inventory and the Disability Rating Index could also significantly predict sick leave in this sample and correctly classified as many patients as the ORQ. However, these questionnaires do not include any work-oriented items and they had a lower specificity than the ORQ. This study suggests that patients' perceptions and beliefs about work and returning to work may be a significant hindrance for actual recovery.  相似文献   

9.
Objective: To examine the reliability of birth certificate data and determine if reliability differs between teaching and nonteaching hospitals. Methods: We compared information from birth certificates and medical records in 33,616 women admitted for labor and delivery in 1993–95 to 20 hospitals in Northeast Ohio. Analyses determined the agreement for 36 common data elements, and the sensitivity, specificity, and positive and negative predictive values of birth certificate data, using medical record data as a gold standard. Results: Sensitivity and positive predictive value varied widely (9–100% and 2–100%, respectively), as did agreement, which was almost perfect for measures of prior obstetrical history, delivery type, and infant Apgar score ( = 0.854–0.969) and substantial for several other variables (e.g., tobacco use ( = 0.766), gestational age ( = 0.726), prenatal care ( = 0.671)). However, agreement was only slight to moderate for most maternal risk factors and comorbidities ( = 0.085–0.545) and for several complications of pregnancy and/or labor and delivery ( = 0.285–0.734). Overall agreement was similar in teaching (mean = 0.51) and nonteaching ( = 0.52) hospitals. Although agreement in teaching and nonteaching hospitals varied for some variables, no systematic differences were seen across types of variables. Conclusions: Our findings indicate that the reliability of birth certificate data vary for specific elements. Researchers and health policymakers need to be cognizant of the potential limitations of specific data elements.  相似文献   

10.
Objectives: Recently, the conditions for disability benefits were redefined in several countries, stimulating employees to participate on the labour market as long as reasonably possible. Little is known of labour participation and quality of life (QoL) of employees with chronic diseases. This study examines the associations between employment status and QoL in COPD patients. Additionally, the role of lung function, and work-related symptoms and exposures on QoL were explored. Methods: Secondary analyses were conducted on baseline data from a randomized control trail. Patients were categorized as: paid-workers; voluntary non-paid workers (e.g., early retired, house wives) or disabled for work. QoL was assessed by the Chronic Respiratory Questionnaire (CRQ). Between-group differences in CRQ scores, and associations between work-related symptoms or irritants and CRQ scores were uni- and multivariately analysed. Results: Two hundred and ten patients with COPD were included [mean age 53.9 (SD 6.8) years, FEV1 %predicted 63.5 (SD 18.5)]. No statistically significant differences in lung function between the employment status subgroups were observed. Multivariable analysis showed that the disabled had lower CRQ scores as compared with paid workers (0.52 point difference, p<0.001). The CRQ scores of voluntary non-paid workers were not significantly different from paid workers. Within the group paid workers, patients with many work-related clinical symptoms and being susceptible to various work-related irritants experienced a lower QoL than patients who had respectively no symptoms, or who were not susceptible to these factors. Conclusions: Patients with COPD who were disabled for work showed equal severity of airflow limitation but worse QoL, as compared with paid workers.  相似文献   

11.
The Clinical Pastoral Education (CPE) model forthe provision of spiritual care represents theemergence of a secularized professionalpractice from a religiously-based theologicalpractice of chaplaincy. The transformation ofhospital chaplaincy into spiritual careservices is one means by which religioushealthcare ministry negotiates modernity, inthe particular forms of the secular realm ofbiomedicine and the pluralism of thecontemporary United States healthcaremarketplace. Spiritual is a labelstrategically deployed to extend the realm ofrelevance to any patient's belief system,regardless of his or her religious affiliation.Theological language is recast as a tool forconceptualizing the spiritual lens. Suchmoves transform chaplaincy from a peripheralservice, applicable only to the few religiouspatients, into an integral element of patientcare for all. Such a secularized professionalpractice is necessary to demonstrate therelevance and utility of spiritual care for allhospital patients in an era of cost-containmentpriorities and managed care economics.  相似文献   

12.
Herbicide 2,4-D formulated as a urea-type polymer was readily destroyed by long-wave uv (356-nm) irradiation, whereas conventional 2,4-D was more resistant. The opposite relationship was noted for polymeric and conventional formulations of dicamba. Polymerized 2,4-D was more resistant to thermal degradation (60°C) than non-polymerized formulations. Ultraviolet degradation of polymerized 2,4-D was eliminated by the incorporation of RYLEX-H and UVINUL D-50, industrial uv absorbers. Exposure of polymeric dicamba to 60°C heat, followed by trapping of the volatile component, indicated that 21 percent was lost by thermal degradation and 46.6 percent by volatilization. Comparable values for non-polymerized dicamba were 37.9 and 60.1 percent.  相似文献   

13.
Summary 4,4-methylene-bis-(2-chloroaniline) (MOCA) and two identified urinary N-acetyl and N,N-diacetyl derivatives were tested in a Salmonella/mammalian microsome assay. No mutagenic activity was observed without rat liver S9 mix activation. In the presence of rat liver S9 mix, the chemicals were mutagens, but the mutagenicity of N-acetyl derivatives to strain TA 100 was reduced when compared to that of MOCA, and a greater amount of S9 was required to exhibit the mutagenicity of the N,N-diacetyl-MOCA. These data suggest that N-acetylation does not account for the mutagenic effectiveness of MOCA.  相似文献   

14.
Alternate Shewhart-type statistical control charts, called g and h charts, are developed and evaluated for monitoring the number of cases between hospital-acquired infections and other adverse events, such as heart surgery complications, catheter-related infections, surgical site infections, contaminated needle sticks, and other iatrically induced outcomes. These new charts, based on inverse sampling from geometric and negative binomial distributions, are simple to use and can exhibit significantly greater detection power over conventional binomial-based approaches, particularly for infrequent events and low defect rates. A companion article illustrates several interesting properties of these charts and design modifications that significantly can improve their statistical properties, operating characteristics, and sensitivity.  相似文献   

15.
Summary Ten iron foundry workers representing typical foundry occupations were examined. The amount of lung contamination was estimated after the workers' thoracic area had been magnetized and the remanent magnetic field measured. Chest radiographs were classified according to the siderotic, silicotic, and nonspecific changes found; and the changes were then divided into four categories.The preliminary results of the electron micrographs indicated that the size and shape of the pollutants varied greatly according to the type of foundry site. In addition, the estimated amount of lung contaminants in the subjects varied between 30 and 600 mg. A good correlation (r=0.86) was obtained between radiological siderotic and silicotic changes, and the correlation between both of these radiological findings and the measured average permanent magnetic field was rather good (r=0.60). There was no correlation between the estimated exposure (neither length nor magnitude) and the amount of retained lung contaminants, and therefore a balance between retention and clearance seemed to have been achieved. These results indicate that the magnetic measuring method can be used to evaluate the amount of lung contaminants retained by foundry workers.  相似文献   

16.
The author provides a brief account of her travel and experiences in several developing countries and explores some of the resulting personal transformations in her attitudes, assumptions and understandings. Persons working with children and youth can learn much from those countries which are economically under-developed, but which retain a simplicity in daily life and a commitment to the central importance of family and community.  相似文献   

17.
Male day care teachers have more to offer young children than their masculine presence. It is suggested that pleas for a male role model are misdirected, and that men in day care have valuable contributions to make by modeling and reinforcing not only positive masculine traits but also positive feminine traits. Emphasis, therefore, is placed upon the balance the male caregiver can provide for a humanized environment for young children. Suggestions are given on ways to establish androgynous environment for current and future caregivers.  相似文献   

18.
While most of the debate on rationing in health care focusses on the distribution of scarce medical resources among competing needs, which we propose to call secondary rationing, this paper is concerned with primary rationing, i.e., the conscious decision by society to limit the amount of resources devoted to a collectively financed health care system. Based upon a number of transparent normative criteria, we analyze whether primary rationing should be performed and, if so, what type should be chosen (hard vs. soft, explicit vs. implicit). Finally we discuss whether age should be used as a criterion in any systematic attempt at primary rationing of health care.  相似文献   

19.
The social and applied human sciences have been built upon the assumption that the normal family consists of a first-marriage conjugal couple cohabiting with biological children. It is taken for granted that the wife should be responsible for child and domestic work, and that the husband should be the family's economic provider and ultimate authority. In the professional literature such traditional family structure is often described as normal in the sense of most common, as well as normal in the sense of well-functioning. Current psychological, sociological, anthropological and historical studies, however, do not support the assumption that the traditional nuclear family is the most natural, common, and/or healthy form of family arrangement. The idealization of the traditional nuclear family has had implications for theory, research, mental health practice, and social policy. Scientists and practitioners have been slow to recognize pathology in traditional nuclear families. Families other than traditional nuclear ones have been rendered invisible or pathologized. It is time for contemporary social and applied human sciences to recognize that the traditional nuclear family is a culturally- and historically-specific construct. It is also time for contemporary social and applied human sciences to develop an account of, and a research agenda about, families that take into consideration their variations across time, place, social class, ethnicity, and culture.  相似文献   

20.
Summary The mutagenicity of urine from a healthy population of young adult men (average age of 23 years), including 61 smokers and 107 nonsmokers, was investigated with the Salmonella/microsome test using the tester strain S. typhymurium TA98. In quantifying the assay, the use of dichloromethane was suitable for eluting the mutagenicity of smokers' urine from the XAD-2 resin column. We assayed mutagenicity in condensates of such dichloromethane eluates and found that the mutagenicity of smokers' urine was significantly higher than that of nonsmokers' urine. In the smokers' group, correlation coefficient between the mutagenicity of the urine and the actual number of cigarettes smoked on the day of urine collection or the average number of cigarettes smoked per day was statistically significant at 0.266 or 0.454, respectively. Our results suggest a correlation between the increase of mutagens in urine and smoking habits.  相似文献   

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