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51.
Ben F. Brammell J. Scott McClain James T. Oris David J. Price Wesley J. Birge Adria A. Elskus 《Archives of environmental contamination and toxicology》2010,58(3):772-782
It has become increasingly apparent that resident fish can develop resistance to chemicals in their environment, thus compromising
their usefulness as sentinels of site-specific pollution. By using a stream system whose resident fish appear to have developed
pollutant resistance (Brammell et al., Mar Environ Res 58:251–255, 2005), we tested the hypothesis that the pollutant-inducible biomarker, cytochrome P4501A (CYP1A), as measured in field-caged
juvenile rainbow trout (Oncorhynchus mykiss), would reflect relative pollution differences between reference and polychlorinated biphenyl (PCB)-contaminated sites. Trout
were caged in the Town Branch/Mud River system (Logan County, KY), a stream system undergoing remediation for PCBs. Fish were
held in remediated (Town Branch), unremeditated (Mud River), and reference sites for 2 weeks during spring 2002. At the end
of this period, gill and hepatic CYP1A expression were measured. To evaluate the relative PCB exposure of caged trout and
provide a reference point against which to calibrate CYP1A response, PCB levels were quantified in sediments from each site.
Hepatic CYP1A expression in caged trout clearly detected the presence of PCBs in the Town Branch/Mud River stream system.
Sediment PCB levels and hepatic CYP1A expression in caged trout produced identical pollution rankings for the study sites.
Gill CYP1A expression, although suggestive of site differences, was not statistically different among sites. Unlike resident
fish, which failed to show site differences in hepatic CYP1A expression in this waterway (Brammell et al. 2005), caged fish proved to be a sensitive discriminator of relative PCB contamination in this system. In summary, we determined
that CYP1A expression in caged fish reflected relative in situ pollutant exposure. The exposure paradigm confirmed that 2 weeks
was a sufficient caging period for evaluating CYP1A response in this species at these temperatures (13–19°C). In addition,
these studies demonstrate that tissue-specific CYP1A expression can provide insights into likely routes of exposure. We conclude
that CYP1A expression in caged trout is a reliable and inexpensive first-pass determination of relative environmental pollutant
exposure and bioavailability in aqueous systems. 相似文献
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Pradeep J Nathan Andrew H Kemp Ben J Harrison 《Neuropsychopharmacology》2003,28(7):1383; author reply 1384-1383; author reply 1385
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A simple method for the rapid screening of hepatotoxic agents is described. Liver slice systems were prepared from rats and mice, and incubated in Krebs-Ringer-Hepes medium with different concentrations of the test compounds. Hepatotoxicity was monitored by determination of liver enzymes in the slice medium. Enzyme leakage was dose- and time-dependent. Histopathological changes in the hepatotoxin-treated slices were well correlated with the extent of enzyme leakage. Species differences in susceptibility to various hepatotoxins could be easily detected by this in vitro system: the dose-toxicity curves revealed that the mouse is more vulnerable than the rat to acetaminophen and furosemide. These findings are well correlated with those of in vivo experiments. A preliminary study showed that, in the same species, the relative toxicities of various chemicals in the liver slice system were similar to those reported in vivo. In summary, these results on the tissue slice system are encouraging. However, much more work will have to be done before the system can be considered sufficiently well validated for routine use. 相似文献
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Mansour Njah Radhia Hergli Jalel Gloulou Slim Ben Ahmed et Moncef Marzouki 《Sozial- und Pr?ventivmedizin》1994,39(5):280-286
Resumé Dans le but d'analyser les besoins d'une population en matière de dépistage des cancers, les attitudes, connaissances et comportements des femmes à propos des cancers du sein et du col utérin sont étudiées, auprès d'un groupe de consultantes tout venant de 3 centres de santé tunisiens (Kalaa-Kebira). Les résultats soulignent la nécessité d'informer la population concernant les facteurs de risque de ces maladies, particulièrement en ce qui concerne le cancer du sein, (1er cancer de la femme en Tunisie) mais surtout sur les signes d'appel et les moyens de dépistage disponibles. Le rôle des professionnels de la santé, plus du généraliste et de la sage-femme que du gynécologue apparait clair auprès des consultantes. L'éducation individuelle et de masse doit cependant aller de pair avec une sensibilisation et une formation des professionnels de la santé eux-mêmes en matière de dépistage.
Knowledges, attitudes and behaviors of Tunisian women about gynaecologic cancers
Summary With the aim to analyze population needs in the field of cancer screening (cervical and breast cancer), attitudes, behaviors and knowledge of a tunisien women group of health service user's were studied. Results clearly demonstrate the necessity to inform the concerned population about risk factors particularly concerning breast cancer (the most frequent cancer in Tunisia) but also early symptoms and available screening methods. This role is alloted to health professionals, more for general practitioners and midwives than for gynaecologists. Health education for women and groups, however, have to go hand in hand with training of health professionals in matter of test screening.
Kenntnisse, Haltung und Verhalten der tunesischen Frauen in Bezug auf gynäkologische Krebse
Zusammenfassung Haltung, Kenntnisse und Verhalten der Frauen gegenüber dem Brustkrebs und dem des Uterushalses wurden an Hand einer Patientinnengruppe in Tunesischen Gesundheitszentren (Kalaa-kebira) erlangt. Die Ergebnisse bestätigen die Notwendigkeit, die Bevölkerung über die Risikofaktoren dieser Krankheiten zu unterrichten, besonders was den Brustkrebs betrifft (den verbreitetsten Krebs bei Frauen in Tunesien), aber vor allem über die Krankheitsanzeichen und die verfügbaren diagnosemethoden. Die Rolle der Gesundheitskräfte, insbesondere die des Allgemeinarztes und der Hebamme, noch vor derjenigen des Frauenarztes, sind den Patientinnen verständlich. Die individuelle sowie die massenhafte Gesundheitserziehung muss Hand in Hand gehen mit einer Sensibilisierung und einer Ausbildung des Gesundheitspersonals in Sachen Diagnosemethoden.相似文献
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A 40-year-old patient with no immune deficiency was admitted because of severe bilateral pneumonia and pleural effusion. The diagnosis of Chlamydia trachomatis pneumonia was confirmed by isolation of the pathogen and the appearance of serum antibodies to Chlamydia species. 相似文献
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