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1.
Forty-nine isolates of Campylobacter pylori were tested for their susceptibility to twenty antibiotics and four anti-ulcer agents by an agar dilution technique. Penicillin and amoxycillin were the most active drugs (MIC90, 0.06 /ml); erythromycin, cefazolin, minocycline, ciprofloxacin, ofloxacin and gentamicin were sligthtly less active (MIC90, 1 g/ml). Moderate activity was found for doxycyclin, rifampin, nitrofurantoin, norfloxacin, pefloxacin, enoxacin, paromomycin, metronidazole and tinidazole. All strains were resistant to trimethoprim (MIC > 512 g/ml). Nalidixic acid (MIC90, > 256 g/ml) and colistin (MIC90, > 64 gg/m1) had little to no activity. Of four anti-ulcer drugs, only bismuth subcitrate showed activity (MIC90, 64 g./ml).Strains resistant to all 4-quinolones were found in patients who had previously received ofloxacin as part of a clinical trial aimed at eradication of C. pylori. These isolates remained susceptible to amoxycillin, tetracyclines and to other classes of antibiotics.Corresponding author.  相似文献   

2.
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   

3.
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   

4.
Summary A cross-sectional study was performed in order to investigate the influence of chronic lead-exposure on the peripheral nervous system. We examined 148 male workers of a storage battery manufacturing plant, who had been exposed to lead metal and inorganic lead compounds for 1 to 28 years (mean 11 years). Fifteen workers with non-occupational risks of peripheral neuropathy (former diseases, alcohol abuse, medication) were excluded from the study. The investigation program comprised: case history, physical examination, analyses of blood- and urine-samples and determination of maximal motor, mixed and sensory conduction velocity (NCV) of the ulnar and median nerve of the right forearm. Objectively no worker showed any signs of health effects related to lead exposure. The Biological Monitoring included the determination of (1) Blood-lead level (Pb-B), (2) Free erythrocyte porphyrins (FEP), (3) -Aminolevulinic acid dehydratase (ALA-D) and (4) -Aminolevulinic acid in urine (ALA-U). Further time-weighted-average (TWA)-values of Pb-B were calculated on the basis of several determinations over the period 1975–1981. The following actual (TWA) median values resulted: Pb-B 53 g/dl (54 g/dl), ALA-U 5.6 mg/l (8.4 mg/l), FEP 2.0 mg/l (2.0 mg/l). The Biologischer Arbeitsstoff Toleranz Wert (BAT) of 70 g//dl for Pb-B was exceeded in 15 workers (11%), and of 15 mg/l for ALA-U in 30 cases (23%). In comparison with age-matched controls, the lead workers showed a mild slowing of NCV with mean values between 0.8 and 2.0 m/s. Multiple stepwise regression analyses revealed statistically significant correlations between the four NCV and age as well as Pb-B. There were better correlations by using TWA than actual data of Pb-B. Consideration of the results of the regression analyses, together with an evaluation of the individual neurophysiological status as a function of internal lead exposure, a dose-effect-relationship was found only in the case of Pb-B exceeding 70 g/dl. From our study it is concluded that chronic lead exposure resulting in blood-lead levels of below 70 g/dl is no occupational risk causing a functionally significant slowing of nerve conduction velocities.With Grants from the Deutsche Forschungsgemeinschaft, Bonn (Project no. Va 23/19-1)  相似文献   

5.
Summary The organochlorine insecticides pp-DDT, its metabolites pp-DDE and pp-DDD, -HCCH, HEOD and PCBs were identified in the fat of mutton birds of New Zealand. The mean levels for six adult birds were: total DDT 17.30 ppm (78% pp-DDE), pp-DDT 1.54 ppm, pp-DDE 13.50 ppm, pp-DDD 0,64 ppm, -HCCH 5.17 ppm, HEOD 0.93 ppm, PCBs 1.83 ppm. All the compounds found in the adult birds except -HCCH, were also present in a chick bird but in considerably smaller amounts.  相似文献   

6.
The herbicides atrazine and linuron, found in Wisconsin's groundwater, were tested alone and in combination, both in vivo and in vitro, to determine their individual and combined genotoxic effects. Human lymphocytes exposed in vitro to either 1 g/ml linuron or 0.001 g/ml atrazine showed little chromosome damage, whereas significant chromosome damage was observed in lymphocytes simultaneously exposed to 0.5 g/ml linuron and 0.0005 g/ml atrazine, suggesting at least an additive model. In another experiment, mice were fed 20 g/ml atrazine, 10 g/ml linuron, or a combination of 10 g/ml atrazine and 5 g/ml linuron in their drinking water for 90 days, after which bone marrow cells and cultured splenocytes were examined for chromosomal damage. None of the treatment groups showed chromosome damage in bone marrow, whereas the cultured splenocytes demonstrated damage in all treatment groups. These experiments suggest that, prior to assessing the risk of a herbicide, it may be necessary to test it in combinations which mimic the mixtures which would occur under field conditions, such as in contaminated groundwater.  相似文献   

7.
Summary Seventeen male manual metal-arc stainless steel welders (mean exposure time 20 years) had far higher levels of chromium in urine than individually matched controls (medians 23 vs 1.5 mol/mol creatinine;10.5 vs 0.7 g/g creatinine). However, there were no signs of kidney damage in tests of function of tubuli (-hexosaminidase, lysozyme, and 2-microglobuline) or glomeruli (albumine clearance).  相似文献   

8.
A capillary blood microsampling technique was tested among urban young children in Stockholm. Blood lead (BPb) and hemoglobin (Hb) concentrations were determined in capillary blood obtained by fingerstick from 41 children, 13–20 months old, and the accompanying parent. The quality control included control for lead (Pb) and cadmium (Cd) contamination of material and equipment used for blood sampling, washing procedures for the hands and fingers to be punctured, comparisons of Pb and Cd concentrations in blood obtained by fingerstick and by brachial vein puncture from the same individuals, analysis of external quality control samples for Pb and Cd in blood together with the collected samples, and evaluation of the analytical performance using linear regression analysis.The results showed that blood sampling material may contaminate the blood samples with amounts of Pb and Cd that would seriously influence the monitoring results in the low concentration range (<100 g Pb/L and <1 g Cd/L). However, it is possible to obtain reliable BPb concentrations (>10 g Pb/L), but not BCd concentrations (<1 g Cd/L), with the capillary blood microsampling technique tested provided that a strict quality control is applied. The sampling procedure tested was well accepted by the children and their parents. The children's median BPb concentration (27 g/L; range 9–73 g/L) was similar to the median BPb concentration of their parents (27 g/L; range 7–74 g/L). However, the correlation between child and parent BPb concentrations was poor (R2=0.20), which may indicate different sources to Pb exposure in children and parents.  相似文献   

9.
Application of a noninvasive method of analyzing skin lipids was considered as a means of monitoring human exposure to organochlorine pesticides. Skin lipids were collected by wiping the face with cotton and purified by gel permeation chromatography and treatment with H2SO4. Organochlorine chemicals were determined by electron capture gas chromatography with a fused silica capillary column.p,p-DDE, -HCH and chemicals related to chlordane were detected in the skin lipids. Residue levels ofp,p-DDE, -HCH and oxychlordane in the skin lipids correlated with those in the adipose tissue; correlation coefficients forp,p-DDE, -HCH and oxychlordane were 0.93, 0.92, and 0.68, respectively. The correlation between skin lipids and adipose tissue for trans-nonachlor was poor ( = 0.46). The component pattern of chlordanes in skin lipids was similar to that of technical chlordane. The results suggested that chemicals in the skin lipids reflected both their accumulation in the body burden and dermal exposure.Skin lipids collected during 1986 to 1988 in Japan were determined forp,p-DDE, -HCH and the chlordanes. Residue levels ofp,p-DDE and -HCH in the aged were high compared with those in the young (=0.31–0.45). Chlordanes were detected from inhabitants in the southern area of Japan where chlordane had been used for termite control.  相似文献   

10.
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   

11.
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   

12.
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   

13.
Conclusion These five topics are different from many of the traditional professional activities of the mental health professions. They have been presented to clarify how the ambiguity of prevention work can be explored and how the substantive merit of primary prevention is increased. The complementary connections between the social sciences and the clinical professions is expected to be enhanced in working on these agendas. The challenge for preventive work is to bring together the insight of citizens and professionals, so that critical thinking and authentic needs for both can be integrated. Working on ideas such as these five can make it possible for professionals and citizens to develop new knowledge for new professional roles and new opportunities for citizen development. Here the professional and citizen become resources for each other, in contrast to the professional treating the subject or patient. Prevention work means creating knowledge that is available directly for community development in contrast to individual treatment.James G. Kelly is with The University of Illinois at Chicago.  相似文献   

14.
This study showed that the socially desirable presentation for a heterosexual male gender dysphoric is one that emphasizes traits and behaviors characteristic of classic transsexualism. Fifty-one homosexual and 64 heterosexual adult male gender patients were administered the Crowne-Marlowe (1964) Social Desirability Scale as well as eight questionnaire measures that tapped various features of the clinical history commonly given great weight in differential diagnosis. The tendency for a heterosexual subject to describe himself in terms of moral excellence or admirable personal qualities was significantly correlated with scores in the transsexual direction on all eight sexological measures; for the homosexual subjects, only one correlation was significant. It is argued that the patients most motivated to create a favorable impression on the examiner are likely to be those most anxious to obtain approval for sex reassignment surgery. Because, in this population, the socially desirable presentation is feminine, it is possible that the differences in the histories produced by transvestites and heterosexual transsexuals are exaggerated to an unknown degree by the motivation of the latter to obtain approval for this operation. The findings do not diminish the important distinction between these groups, but they do suggest caution in interpreting the self-report data that have been used in comparing them.  相似文献   

15.
Blood and breast milk samples of 16 women were analyzed for PCBs (polychlorinated biphenyls) and some organochlorine pesticides during eight intervals of a 98 day lactation period. Although a general downward trend in residue levels of blood and breast milk was evident, this trend was interrupted by sporadic increases. Most residues in breast milk showed an apparent increase during the first 30 days of lactation, which was not statistically significant. However, during lactation a statistically significant decrease was observed for the following residues, expressed on a milkfat basis: HCB (hexachlorobenzene), oxychlordane, transnonachlor (1-exo, 2-endo, 3-exo-4,5,6,7,8,8-nonachloro-3a,4,7,7a-tetrahydro-4,7-methanoindene), HCH (hexachlorocyclohexane),p,p-DDE andp,p-DDT. Average milk/blood ratios for PCBs, HCB, oxychlordane(1-exo,2-endo-4,5,6,7,8,8-oc-tachloro-2,3-exo-epoxy 2,3,3a,4,7,7a-hexa-hydro-4,7-methanoindene),p,p-DDE (2,2-bis-(p-chlorophenyl)- 1, 1-dichloroethylene), dieldrin (1,2,3,4, 10,10-hexachloro-exo-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro- 1,4-endo- exo- 5,8-dimethanonaphthalene) and p,p-DDT (1,l-bis-(p-chlorophenyl)-2,2,2-trichloroethane) levels were 23, 20, 9, 19, 5 and 30 respectively. Milk/blood ratios for PCB andp,p-DDE levels remained relatively constant during lactation (coefficient of variation 20). Accumulation of residues in infant body fat were theoretically estimated  相似文献   

16.
Summary Lead concentrations were measured in the deciduous teeth (incisors) of 302 children living in a lead-smelter area in the FRG (Stolberg, Rheinland) and of 86 children living in a nonpolluted rural area (Gummersbach, Bergisches Land). Blood lead levels were determined in 83 of the children living in the lead smelter area. On average, tooth lead levels of children living in the smelter area (mean: 6.0 g/g; range: 1.49–38.5 g/g) were significantly higher than those of children living in the rural area (mean: 3.9 g/g; range: 1.6–9.4 g/g). Blood lead levels were 6.8–33.8 g/100 ml (mean: 14.3 g/100 ml). Children of lead workers had on average higher tooth lead and blood lead levels than children of people who were not lead-workers. Tooth lead levels increased with increasing duration of residence in the lead-smelter area and with the degree of local environmental pollution by lead, as indicated by the lead content of the atmospheric dust fall-out around the children's homes. The correlation coefficient of tooth lead vs blood lead was 0.47. The intra-individual variability of tooth lead levels was low (r=0.86), and tooth lead levels of brothers and sisters were similar (r=0.75), suggesting that tooth lead may be used as a representative and reliable indicator of long-term lead exposure.This study was carried out at the request and with support of the Ministerium für Arbeit, Gesundheit und Soziales NW, Düsseldorf  相似文献   

17.
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   

18.
Summary Aroclor 1242 is inhibitory to long-term batch growth ofE uglena gracilis at 10 ppm. Exposure to PCB's, subsequent to an initial drop of 50% in the first 30 minutes, does not appear to inhibit photosynthesis on a per cell basis over the time span of four hours. Consequently our experimental findings suggest that inhibition of population growth does not lie directly in the photosynthetic pathway despite the initial inhibition by Aroclor 1242 onEuglena gracilis in light. Dark absorption of bicarbonate appears to decrease with increased PCB exposure. This decrease may be causally related to the population growth inhibition observed.  相似文献   

19.
The literature on the socialization of children is reviewed. It is concluded that a major factor contributing to conduct problems in children is the lack of effective child caring at home. The special adult-child relationship which differentiates biological from psychological parenting is described. Implications for the residential treatment of children are discussed.  相似文献   

20.
Summary The objective of the study was to assess whether moderate occupational exposure to lead may be associated with early changes in potential target organs (thyroid, testes, kidney, autonomic nervous system). Workers exposed to lead in a lead acid battery factory (n = 98; mean blood lead 51 g/dl, range 40–75 g/dl) and 85 control workers were examined. None of the indicators of kidney function (in urine: retinol-binding protein, 2-microglobulin, albumin,N-acetyl--d-glucosaminidase; in serum: creatinine, 2-microglobulin), endocrine function (follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, thyroxine, triiodothyronine) and autonomic nervous system (R-R interval variations on the electrocardiogram) were correlated with lead exposure (blood lead or duration of exposure) or showed significantly different mean values between the exposed group and controls. These results and an assessment of the published data suggest that compliance with the Directive of the Council of the European Communities on lead exposure (health surveillance in workers whose lead in blood exceeds 40 g/dl and removal from exposure when blood lead exceeds 70–80 g/dl) would prevent the occurrence of significant biological changes in the majority of lead-exposed workers.  相似文献   

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