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1.
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   

2.
Lymantria dispar (gypsy moth) larvae were reared on both a natural diet of oak leaves and an artificial medium contaminated independently with four different metal nitrates. Larvae were contaminated up to pupation either from 1st or 4th instars at four concentrations differing by a factor of 5. The lowest concentration levels were 2 g/g Cd, 4 g/g Pb, 10 g/g Cu, and 100 g/g Zn based on nutrient medium dry weight. Developmental rate, growth, mortality and reproductive success were determined. No-Observed-Effect-Concentrations (NOECs) calculated were dependent on the metal, the parameter investigated and the stage at which exposure commenced. In general, larvae exposed from the 4th instar were less susceptible to metal toxification than those exposed from hatching. Considering all parameters investigated, dietary NOECs were determined to be 2 g/g Cd, 4 g/g Pb, 10 g/g Cu, and 100 g/g Zn.  相似文献   

3.
This article is based on data gathered through 60 qualitative interviews conducted within the realm of three research projects that have used culture-appropriate lenses to study the postmigration situation of late-in-life Iranian immigrants to Sweden. The findings gathered through these studies were interpreted against the backdrop that culturally appropriate nursing theories provide. This meant that it was, at times, these elders backgrounds as cultural others that were implicitly used to make sense of the various issues that were brought to the fore by these studies. The particular issue with which this article is concerned is the unusualness of these elders explanatory models of illness. Inspired by the concept definition of situation in the symbolic interactionist perspective and by the feeling that this perspective might bring about a different interpretation of the original findings regarding their understandings of illness and disease, we set out to conduct a secondary analysis of these elders explanatory models of illness. The findings presented in this article will show how the elderly Iranian immigrants interviewed in these three studies utilize the process of late in life migration as a point of reference for their understandings of what has caused the illnesses from which they suffered. Hereby we will suggest that the unusualness of their explanatory models of illness might be best understood if we focus on what they shared as immigrants (i.e., the fact that the process of late-in-life migration has made their culture obsolete) as opposed to what they shared as Iranians (i.e., their culture of origin).  相似文献   

4.
Incurred fumigants were determined from twenty-two food items before and after routine large-scale preparation of samples to see if these or similar kinds of chemicals were entering the samples during the preparation. This preparation includes making the samples table ready before compositing them for analysis. The following five fumigant residues were determined by gas chromatography (GC): carbon disulfide (CS2), carbon tetrachloride (CCl4), chloroform (CHCl3), methyl chloroform (CH3CCl3), and tetrachloroethylene (or perchloroethylene, PCE). The number of residues determined from each sample ranged from none to four. The amounts determined varied significantly between the before and after portions from several samples. Four samples gained at least one new residue during the preparation. Six lost most of the residues determined from the original before portions, and 12 contained essentially the same residues before and after the preparation, although the amounts varied between the two portions. In samples where the variant residues were detected in both portions, five showed a tenfold or greater increase of CHCl3 or CCl4 and two showed a ten-fold or lesser decrease of CH3CCl3 or PCE in the after portions.  相似文献   

5.
Media reviews     
Of the three films reviewed in this issue, only the first, All Women Have Periods, deals with both areas of sexuality and disability. The second film, A Masturbatory Story, deals with sexuality but not disability. The third film, A Different Approach, deals with disability but not sexuality. The reason I have included the last two films are that A Masturbatory Story is one of the best, most permission giving films I have seen on the subject of masturbation and A Different Approach while focusing on employment of the disabled, is one of the most entertaining and effective films I have seen dealing with attitudes.  相似文献   

6.
The levels of the health-related quality of life (HR-QoL) were analyzed in hereditary hemorrhagic telangiectasia (HHT) patients. The Short Form-36 Health Survey (SF-36) was administered to 50 HHT patients and scores were compared to a cohort of 2301 normal subjects. Clinical variables were patient age, illness duration, number of epistaxis episodes in the previous year and hemoglobin levels. Physical functioning, physical role limitations, bodily pain, social functioning, emotional role limitations and the physical component scores were lower among females. In multivariable analyses increasing age was related to lower physical functioning (P<0.04), physical role limitations (P<0.008), bodily pain (P<0.05) and emotional role limitations (P<0.01), while higher hemoglobin levels improved physical functioning(€P<0.03). The number of epistaxis episodes was negatively associated with physical role limitations (€P<0.009), vitality (P<0.002), social functioning (P<0.001), physical component summary (€P<0.001) and bodily pain (P<0.01). Illness duration was negatively related to the mental component summary (P<0.004). HHT patients had a lower HR-QoL with respect to normal controls in all domains except for bodily pain. Females had lower scores for several domains. Epistaxis was the most important clinical variable.  相似文献   

7.
Emergency room (ER) utilization and hospitalization were studied as indicators of the impact of improvements in pediatric primary care services in an Israeli development town, Ofakim, population 12,000. One of the two pediatric services was upgraded in 1976 through the introduction of pediatric faculty, integration of preventive and curative services and conversion of the medical records to a problem-oriented format ( experimental clinic B ). The primary care system remained unchanged in the second clinic ( traditional clinic A ). During 1980, ER utilization by the B clinic population was 9.3/100 compared with 17.6/100 for the A clinic population. Fifty two percent of the B clinic population patients reaching the ER were hospitalized compared with 25% of A clinic patients.The lower ER utilization rate represents a significant saving for the health services, and educational interventions are suggested from the study. Analysis of ER utilization data seems to offer useful information for overall planning and monitoring of ambulatory services for a community.Corresponding author.  相似文献   

8.
Although estimates suggest that there are upwards of 5 million migrant farmworkers in the United States, scant research has explored the stressors associated with their lifestyle. Contrary to previous work, the present study directly explored migrant farmworkers' own perceptions of what is difficult in their lives. The purposes of the present study were to qualitatively explore, from a phenomenological standpoint, the stressors associated with living as a migrant farmworker in the Midwest United States; and to determine the stressors that were most strongly related to symptoms of anxiety and depression. The findings indicated that 18 stressors were commonly experienced by the migrant farmworkers and that the farmworkers experienced overall elevated levels of anxiety and depression. A number of stressors that were not previously reported in the literature were identified. The stressors of rigid work demands and poor housing conditions were significantly associated with higher levels of anxiety and low family income/living in poverty and rigid work demands were significantly associated with depression. Implications of findings and prevention strategies are discussed.  相似文献   

9.
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   

10.
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   

11.
Background: Although interest in the intendedness or the planning status of a pregnancy goes back many centuries, it is only since 1941 that questions about these issues have been asked systematically in large-scale surveys. More recently, questions about intendedness have become standard features of the National Survey of Family Growth and of the Pregnancy Risk Assessment Monitoring System (PRAMS). Interest in and concern about the large numbers of unintended pregnancies reported in those surveys resulted in an Institute of Medicine report on the subject and the inclusion of a national health objective for increasing the proportion of pregnancies that are intended in Healthy People 2000 and Healthy People 2010. Needs: The terms, intended, unintended, mistimed, wanted, unwanted, and planned are often used without significant attention being paid to their meaning or how they are derived from survey questions. There is a particular need to distinguish between terms that define attitudes and those that define behaviors. In addition, research has revealed that women are often happy despite experiencing an unintended pregnancy and that contraceptive failures do not always result in a report of an unintended pregnancy. Objectives: Researchers have begun to ask questions about the meaning of the intendedness concept and its relationship to what women express as their feelings about pregnancies and births. This article, and this entire issue, is an attempt to make the reader aware of the current issues in this area and to suggest additional research that is needed to enable policy makers and program planners to design programs that will better assist couples in meeting their fertility goals.  相似文献   

12.
Egg yolk was spiked withp,p-dicofol (p,p-DCF) (0.1–2.0 g/gm),p,p-dichlorobenzophenone (p,p-DCBP) (0.1–2.0 (g/gm), and 1,1-bis(4-chlorophenyl)-2,2-dichloroethylene (p,p- DDE) (0.05–1.0 g/gm). The fortified egg yolk (2–5 g) was mixed with acetonitrile to extract non-fat organic materials. After removal of acetonitrile, the spiked chemicals were separated with a column chromatograph packed with acid alumina. Recovery efficiencies forp,p-DCBP andp,p-DDE were determined by gas chromatography, and forp,p-dicofol by high performance liquid chromatography. The recovery efficiencies forp,p-dicofol,p,p-DCBP andp,p-DDE were 77.2–93.8%, 84.1–101.1%, and 88.5–96.0%, respectively.  相似文献   

13.
Levels of HCH, HCH, HCH,o,pDDE,p,pDDE andp,pDDT were measured in 59 samples of colostrum collected in the autumn 1982 and the spring 1983 from healthy nursing mothers on the third day after delivery. Pesticide residues were identified and quantitated on a gas chromatograph. Concentrations of HCH were significantly higher in the autumn (mean, 1.71g/L) than in the spring (0.67g/L), while concentrations of HCH were significantly lower in the autumn (0.49g/L) than in the spring (1.50g/L). The differences between the two seasons were not statistically significant for HCH (0.95 g/L vs 0.88g/L),o,pDDE (0.73g/L vs 1.34g/L),p,pDDE (68.63g/L vs 53.72g/L) andp,pDDT (20.00 (g/L vs 14.29 (g/L).Calculated average daily HCH (Lindane) intake of 0.04g/kg body wt (b.w.) and total DDT intake of 4.16 (/kg b.w. in a 3.5 kg newborn, ingesting 60 ml/kg b.w. of colostrum on the third day of life was below the upper limit of FAO/WHO Acceptable Daily Intake (ADI) (0.01 mg/kg b.w. for Lindane and 0.005 mg/kg b.w. for DDT) in the spring. In the autumn, Lindane intake of 1.10k/kg b.w. was below the FAO/WHO ADI and total DDT intake of 5.36 g/kg b.w. was slightly above the FAO/WHO ADI.  相似文献   

14.
The effects of atrazine and a combination of alachlor, atrazine, metolachlor, and metribuzin on the productivity and nutrient uptake rates of native streamAufwuchs communities were investigated in two separate artificial stream experiments. After an 8-day colonization period, the first experiment employed constant doses of atrazine at 0 g/L (control), 24 g/L and 134 g/L. The second experiment employed a pulsed dose having maximum concentrations of 35 g/L alachlor, 109 g/L atrazine, 90 g/L metolachlor, and 21 g/L metribuzin. Each 20-day experiment was run at both 10C and 25C. Constant exposure to 24 g/L atrazine yielded a significant reduction in both ash-free dry weight (AFDW) and chlorophylla at 25C but not at 10C. Constant exposure to 134 g/L atrazine yielded significantly less AFDW and chlorophylla at both temperatures. The pulsed exposure to four herbicides yielded significantly less AFDW at both temperatures, while chlorophylla was significantly less only at 10C. During continual exposure to 134 g/L atrazine, both NO2 + NO3 and silica uptake rates appeared to be reduced at both temperatures, although the differences were generally not statistically significant. At 10C uptake rates of soluble reactive phosphorus and NO2 + NO3 were depressed temporarily by exposure to the pulse of four herbicides, recovering to control rates within a few days, while no effect on uptake rates was discerned at 25C. The temperature difference between experimental runs had a greater effect on nutrient uptake rates than did the herbicide treatments during a run. The results indicate thatAufwuchs growth and nutrient uptake rates may be reduced temporarily by herbicide exposures in agricultural streams. However, greater effects on these processes may be exerted by other factors accompanying storm events, such as reduced temperatures.  相似文献   

15.
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   

16.
The mycelial (25°C) and yeast-like (37°C) forms of Penicillium marneffei clinical and type strains were investigated for their in vitro susceptibility to amphotericin B (AmB), 5-fluorocytosine (5-FC), fluconazole (FLU) and itraconazole (ITZ), using Bacto antibiotic medium 3, yeast-nitrogen, Sabouraud's dextrose (pH 5.7) and high resolution (pH 7.1) broth media (1ml/tube), respectively. Results indicated that the minimal inhibitory and minimal fungicidal concentrations (MICs and MFCs) for the mycelial cultures of P. marneffei to AmB were in the range 0.78–1.56 and 0.78–3.125 g/ml, respectively, as against 3.125–25 g (MICs) for the yeast form cultures. The MFCs to AmB for the yeast form were one dilution higher. The MICs to FLU were generally lower for the yeast form (6.25–25 g) than the mycelial form (25–50 g/ml), whereas MFCs for the mycelial cultures were > 100 g as compared to 6.25–100 g for their yeast form. The MICs for the mycelial form to 5-FC ranged from < 0.195–0.39 g. Higher MICs (6.25 g) were recorded for their yeast form. The MFCs to 5-FC for the yeast form were 25–100 g/ml. The MICs for the mycelial form to ITZ ranged from < 0.195 to 3.125 g/ml. Higher values (< 0.195–50 g) were recorded for their yeast-like form. The MFCs to ITZ for mycelial and yeast forms ranged from < 0.195–0.39 and 25–100 g/ml, respectively. Results indicate that P. marnefei's yeast form is more sensitive to FLU and ITZ (8 of 10 strains) while the mycelial form displayed greater susceptibility to AmB and 5-FC. The MICs for ITZ remained steady in SD medium, pH 5.7 to 7.1. However, some strains gave higher MIC values (0.39–1.56 g/ml) when tested in the HR.  相似文献   

17.
Summary A rapid determination of erythrocyte pyrimidine 5-nucleotidase (P5N) activity in lead workers was carried out using a high-performance liquid chromatograph (HPLC). The P5N activity had a good negative correlation with the concentration of lead in blood (PbB) ranging from 16 to 96 g/dl (r = -0.82, n = 77). Further, the P5N was compared with other biological parameters: erythrocyte -aminolevulinic acid dehydratase (ALAD) activity, erythrocyte protoporphyrin (PROTO), urinary -aminolevulinic acid (ALA) and urinary coproporphyrin (COPRO).The correlation coefficients between P5N and ALAD, log PROTO, log ALA, and log COPRO were 0.59, –0.72, –0.65, and –0.61, respectively. On the other hand, the normal value of P5N obtained from 72 healthy subjects was 11.9 ± 2.1 units; ol uridine/h/g Hb (mean ± SD), indicating that the lower limit of 95% confidence interval for normal P5N was about 8 units. When P5N was cut off at 8 units in 77 lead workers, the validity (sensitivity + specificity) for PbB 40 g/dl, PbB 60 gg/dl, erythrocyte PROTO 150 g/dl RBC, urinary ALA 6 mg/l, and urinary COPRO 150 g/l was 1.66, 1.76, 1.57, 1.68, and 1.60, respectively. From these results, it was confirmed that the erythrocyte P5N test is suitable for the biological monitoring of exposure to lead in a wide range, and its activity is useful in predicting the disturbance of porphyrin metabolism induced by lead.  相似文献   

18.
Summary The concentrations of free cyanide in the blood and in the urine, and the levels of free thiocyanate (oxidized to cyanide and distilled) as well as total thiocyanate (directly determined and quite unspecific) were determined in the urine of 140 volunteers.There were four main categories of volunteers: (i) non-smokers, not exposed to cyanide in the atmosphere, (ii) smokers, not exposed to cyanide, (iii) non-smokers, exposed to various levels of cyanide in their occupation, and (iv) smokers who were also exposed to cyanide.The cyanide concentration in the blood did not show a clear relationship to either smoking or moderate occupational exposure; the levels were found to lie between 2.0 and 15.0 g of free cyanide per 100 ml of blood, with an average of 5.4 g for all categories of volunteers.It was found that the individual concentrations of free CN and CNS in the urine varied considerably and could not be used for detecting undue chronic exposure to cyanide at the concentrations encountered in the atmosphere. The average values, on the other hand, varied in a regular pattern for each of the four categories listed above. The influence of smoking had a far greater effect on the values obtained than the influence of atmospheric cyanide.Because of the great variations caused by other factors, concentrations of CN and CNS in the urine are not appropriate tools for individual routine control of minor occupational exposure to cyanides. However, non-smokers exposed to moderate cyanide levels in the air, and any individual exposed to high cyanide levels show higher than average values of CN and CNS in their urine.The cyanide values reported in this paper may be useful for the evaluation of analytical results from individual cases where poisoning from cyanide in the atmosphere is suspected.  相似文献   

19.
Toxicity of Cadmium (Cd), Chromium (Cr), Copper (Cu), and Mercury (Hg) on the early developmental stages of Ciona intestinalis was investigated. Developmental defects of larvae after exposure of gametes throughout their development to the larval stage were assessed. Gamete exposure to increasing metal concentrations resulted in a significant decrease of the percentage of normally hatched larvae, showing median effective concentrations (EC50) of 721 g/L (6.42 M) for Cd, 12772 g/L (226 M) for Cr, 36.6 g/L (0.576 M) for Cu, and 44.7 g/L (0.223 M) for Hg. Larval attachment was significantly affected when gametes were exposed to the metals throughout development. The EC50 reducing larval attachment by 50% were 752 g/L (6.7 M) for Cd, 15026 g/L (289 M) for Cr, 67.8 g/L (1.607 M) for Cu, and 78.1 g/L (0.389 M) for Hg. Therefore, on a molar basis Hg is three times more toxic than Cu, 20–30 times more than Cd, and 700–1000 times more toxic than Cr, for both responses.  相似文献   

20.
Effective copper and cadmium concentrations which limited the growth of two chlorophytes by 50%, EC(50)s, after 96 h of static exposure were determined. EC(50)s were 5.94 gM copper and 4.55 M cadmium for Dunaliella salina, and 0.78 M copper and 0.025 M cadmium for Chlamydomonas bullosa. The relationship of the two cations was synergistic towards the growth of both species. Chronic exposure to 4.5×10–6 M cadmium or 4.9×10–4 M copper increased the sensitivity of C. bullosa by 26% and 29% towards cadmium and copper, respectively. Changes in co-tolerance were not observed. Cd-treated D. salina was 50% more tolerant towards this cation, whereas Cu-treated cultures showed extreme sensitivity towards copper and co-sensitivity towards cadmium. Furthermore, the phylogenetic hypothesis, predictive of toxic response, failed to hold at the familial level.This work was submitted by Ioanna Visviki to the Department of Biology of the Graduate School of the City University of New York in partial fulfillment of the requirements of the PhD degree.  相似文献   

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