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1.
Viral pollution in shellfish has been analyzed simultaneously across a wide range of geographical regions, with emphasis on the concomitant variations in physicochemical characteristics and social features. The methods for sample treatment and for the detection of human enteric viruses were optimized by the participating laboratories. The second part of this study involves the selection of a protocol for virus detection, which was validated by analyzing the distribution and concentration of human viral pathogens under diverse conditions during an 18-month period in four European countries. Shellfish-growing areas from diverse countries in the north and south of Europe were defined and studied, and the microbiological quality of the shellfish was analyzed. Human adenovirus, Norwalk-like virus, and enterovirus were identified as contaminants of shellfish in all the participating countries. Hepatitis A virus was also isolated in all areas except Sweden. The seasonal distribution of viral contamination was also described. Norwalk-like virus appeared to be the only group of viruses that demonstrated seasonal variation, with lower concentrations occurring during warm months. The depuration treatments currently applied were shown to be adequate for reducing Escherichia coli levels but ineffective for the elimination of viral particles. The human adenoviruses detected by PCR correlate with the presence of other human viruses and could be useful as a molecular index of viral contamination in shellfish.  相似文献   

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The percentage of winter wheat seeds killed by slugs was measured, together with various risk factors, at 93 sites throughout the UK from 1987 to 1990. Estimates of slug populations at each site were obtained from traps baited with methiocarb pellets. The peak number of slugs trapped during the period from July until just before cultivation accounted for 26% of the variability in seed damage, more than any other single risk factor. A combined function of the number of slugs trapped at drilling and the percentage of fine soil aggregates in the seed-bed accounted for 21% of the variability in seed damage. Both (i) the peak number of slugs trapped before drilling, and (ii) the combined function of number of slugs trapped at drilling and the percentage of fine soil aggregates in the seed-bed, have potential for identifying fields with a negligible risk of slug damage to wheat seeds. However, further research is needed to improve the accuracy of forecasting slug damage. In particular, other forms of trap should be tested for their potential use in providing more accurate estimates of slug numbers and biomass at drilling, and techniques of assessing seed-bed conditions should be improved. The percentage of seedlings grazed by slugs was correlated with the numbers of slugs trapped before drilling, at drilling and after crop emergence.  相似文献   

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AIMS: Current measures for controlling the public health risks associated with bivalve molluscan shellfish consumption rely on the use of Escherichia coli to indicate the sanitary quality of shellfish harvesting areas. However, it has been demonstrated that E. coli is an inadequate indicator of the viral risk associated with shellfish. An alternative indicator organism, male-specific RNA (FRNA) bacteriophage has been proposed for this role. This study compared the distribution of E. coli and FRNA bacteriophage in shellfish harvesting areas. METHODS AND RESULTS: A total of 608 shellfish samples from 49 shellfish harvesting areas were analysed for E. coli and FRNA bacteriophage using standard published methods. The geometric mean concentration of FRNA bacteriophage in all samples was over three times greater than that of E. coli (1800 and 538 counts/100 g for FRNA bacteriophage and E. coli, respectively). In contrast to E. coli, FRNA bacteriophage concentrations were strongly influenced by season with a geometric mean count of 4503 PFU/100 g in the winter (October-March) compared with 910 PFU/100 g in the summer (April-September). CONCLUSIONS: FRNA bacteriophage were present in shellfish at higher concentrations than E. coli. Elevated levels of FRNA bacteriophage observed in the winter concur with the known increased viral risk associated with shellfish harvested at that time of year in the UK. Levels of FRNA bacteriophage found in many shellfish from category B harvesting areas would not be eliminated by conventional treatment processes. SIGNIFICANCE AND IMPACT OF THE STUDY: Data from this study will inform future proposals to introduce FRNA bacteriophage as an indicator of the viral risk associated with shellfish.  相似文献   

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Seven years after the ban of avoparcin, VREF could still be isolated within sectors of the UK broiler industry. The aim of this study was to assess whether there is a carryover of VREF between consecutive flocks of birds, to conduct a preliminary investigation of possible routes of entry of VREF into broiler houses and to follow the dynamics of VREF shed by growing birds. A series of nine visits were made to two of six houses on a conventional broiler farm. A total of 343 vanA VREF were recovered from environmental (95/843) and faecal (248/416) samples. Significant differences were observed in the carryover of VREF between pre- and postcohort postcleaning and disinfection visits (RR 0.57, P=0.006). Ninety-nine percent of the VREF isolates were resistant to more than five antimicrobials, with 42 isolates (n=49) positive for erm(B) and 32 (n=40) for vat(E). Pulsed field gel electrophoresis (PFGE) typing identified 50 PFGE types within 15 different PFGE clusters of 90% similarity, demonstrating a high level of genetic diversity within VREF populations from epidemiologically related broiler flocks and broiler houses. Further characterization of Tn1546 from different clones showed a low diversity of Tn-types, suggesting horizontal transfer of resistance determinants between different genetic clones. Thus, this study does not only show the persistence of VREF but also of multi-drug resistant lineages of VREF.  相似文献   

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ObjectivesTo identify whether psychiatric disturbance in parentally bereaved children and surviving parents is related to service provision.DesignProspective case-control study.SettingTwo adjacent outer London health authorities. Participants45 bereaved families with children aged 2 to 16 years.ResultsParentally bereaved children and surviving parents showed higher than expected levels of psychiatric difficulties. Boys were more affected than girls, and bereaved mothers had more mental health difficulties than bereaved fathers. Levels of psychiatric disturbance in children were higher when parents showed probable psychiatric disorder. Service provision related to the age of the children and the manner of parental death. Children under 5 years of age were less likely to be offered services than older children even though their parents desired it. Children were significantly more likely to be offered services when the parent had committed suicide or when the death was expected. Children least likely to receive service support were those who were not in touch with services before parental death.ConclusionsService provision was not significantly related to parental wishes or to level of psychiatric disturbance in parents or children. There is a role for general practitioners and primary care workers in identifying psychologically distressed surviving parents whose children may be psychiatrically disturbed, and referring them to appropriate services.

Key messages

  • Parentally bereaved children show high levels of psychological disturbance, with boys being more vulnerable than girls
  • Surviving mothers show more psychiatric morbidity than surviving fathers
  • Psychological distress in bereaved parents is associated with psychological difficulties in their children
  • Service provision for bereaved children is not determined by mental health difficulties in either parents or children, or by parental wishes; it is influenced only by the manner of parental death and the age of the child
  • The mismatch between need and service provision indicates a role for general practitioners and primary care workers in identifying distressed or disturbed families in need of public or voluntary service help
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Spatial and temporal variations in daily grasspollen counts and weather variables aredescribed for two regions with differentbio-geographical and climatic regimes, southernSpain and the United Kingdom. Daily averagegrass pollen counts are considered from sixpollen-monitoring sites, three in southernSpain (Ciudad Real, Córdoba and Priego) andthree in the United Kingdom (Edinburgh,Worcester and Cambridge). Analysis shows thatrainfall and maximum temperatures are importantfactors controlling the magnitude of the grasspollen season in both southern Spain and theUnited Kingdom, and that the strength anddirection of the influence exerted by thesevariables varies with geographical location andtime.  相似文献   

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Over the past decade the United Kingdom had the second highest number of cases of imported malaria among European countries. There has been a substantial rise in recorded cases of malaria during the past three years though some of it may be due to improved notification. Fatal cases of malaria in visitors to Africa have averaged 6.5% of reported infections due to Plasmodium falciparum. Attacks of vivax malaria may occur several months after travellers return from a malarious country.  相似文献   

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To assess whether the ethnic origin of applicants affects their likelihood of being accepted into medical school in the United Kingdom the outcome for the 2399 applicants who applied to read medicine at university in 1986 and included St Mary''s Hospital Medical School as one of their five choices was studied prospectively. Altogether 2040 of the 2399 applicants were British (United Kingdom) nationals, constituting 24.7% (n = 8249) of all home applicants for medicine in 1986, and 1971 of them with postal addresses in the United Kingdom were sent questionnaires asking about their ethnic origin, whether English was their first language, and about their attitudes to ethnic monitoring. A total of 1817 (92.2%) applicants returned the questionnaire, 401 (22.6%) saying that they were from an ethnic minority group and 393 (21.6%) having non-European surnames. Multiple logistic regression identified 11 significant predictors of successful application, of which grades at O and A level, application after A levels, and date of application were the most important. After taking these four variables into account the predicted acceptance rates for home students on the basis of their application forms alone were 47.8% for white applicants and 35.6% for applicants from ethnic minority groups compared with actual acceptance rates of 49.6% and 27.3%, respectively. The difference in success of white and non-white applicants could partly but not entirely be explained by differences in the characteristics considered to be important in a professional context by selectors during shortlisting of candidates: academic ability, interests, and contribution to the community. No differences in the success rate of applicants from ethnic minority groups to individual medical schools could be identified. More research is needed to discover how perceptions of professional suitability are assessed from application forms and interviews.  相似文献   

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Genetic structure in the United Kingdom   总被引:1,自引:0,他引:1  
Y Imaizumi 《Human heredity》1974,24(2):151-159
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17.
Over 2,000 cases of imported malaria have been confirmed by blood examination. Ninety percent. of cases from tropical Africa were infected with P. falciparum. Most of the patients were Caucasians and had primary infections. All developed fever within a month after arrival and most of them within two weeks of arrival. In some patients malaria parasites were seen in routine blood films.Developing forms of P. falciparum were always present in the peripheral blood of patients suffering from a primary attack which was not diagnosed or treated until a week or more after the onset of fever.All deaths investigated were caused by P. falciparum and were primary infections.In not one of the P. falciparum infections did the victim continue taking prophylactic drugs for more than a few days after leaving the endemic area. Had drugs been continued for one month probably not a single overt case of P. falciparum would have occurred.A primary attack of P. falciparum malaria is seldom, if ever, classical in that the fever is never tertian and may resemble clinically many other diseases.Children in boarding-schools returning from the tropics should be supplied with prophylactic tablets and instructions to the matron. If there is an epidemic of a fever any students who have recently returned from the tropics should have a blood film examined for malaria.The risk of contracting malaria among drug addicts is considerable, especially with P. falciparum.  相似文献   

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Forest-products entomology in the United Kingdom   总被引:1,自引:0,他引:1  
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Though established quality control standards were maintained, the bioavailability of digoxin from Lanoxin tablets produced in the United Kingdom fell in 1969, and was restored in 1972. After 1·5 mg doses of representative batches, tablets made between 1969 and 1972 produced mean values for area under the 50 hours plasma concentration/time curve of 36·6 ng/ml/hr and four-day urinary excretion of 340 μg, compared with respective values of 67·5 ng/ml/hr and 696 μg for recently produced tablets.After 0·5 mg doses of four recent independently produced batches of Lanoxin tablets no significant between-batch difference was found for area under the plasma concentration/time curve or cumulative urinary excretion.Absorption of digoxin from batches of Lanoxin manufactured since May 1972 is uniform and consistent. Content uniformity is an inadequate measure of tablet quality, and consistent digoxin bioavailability cannot be ensured by existing regulations.  相似文献   

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