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51.
Monoclonal antibodies are able to provide information on the surface topography of biopolymers. Antibodies capable of inhibiting the activities of cutinase and parathion hydrolase have been identified in order to probe the sites of pesticide inhibition. Kinetic studies were employed to determine whether organophosphate pesticide binding was directly prevented by antibody binding. Prior binding of chlorfenvinphos and methyl paraoxon to cutinase inhibited subsequent binding by the monoclonal anti‐cutinase antibodies. The role of antibodies in probing enzyme structure is discussed.  相似文献   
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OBJECTIVES: To examine the incidence and mortality of cancer near the Pan Britannica Industries factory, Waltham Abbey, after reports of a possible cluster of all cancers and brain cancer in the vicinity. METHOD: Small area study of cancer incidence 1977-89, and mortality 1981-92, within a 7.5 km radius of the factory site. Postcoded cancer registrations and deaths in the study area were extracted from national data sets held by the Small Area Health Statistics Unit and compared with expected numbers computed by applying national rates stratified for age, sex, and deprivation to the local population (1981 and 1991 censuses). Observed/ expected (O/E) ratios were examined from 0-1 km and 0-7.5 km of the plant, and tests applied for a decline in relative risk with distance up to 7.5 km. RESULTS: There were 12,859 incidence cancers (1977-89) from 0-7.5 km (O/E ratio 1.04; 95% confidence interval (95% CI) 1.02 to 1.06) and 385 from 0-1 km (O/E 1.10; 1.00 to 1.22). There was an excess of skin melanoma from 0-1 km based on 11 cases (O/E 2.13; 1.06 to 3.80), and an excess from 0-7.5 km of cancer of the lung, stomach and pancreas combined, and prostate (O/Es ranged from 1.09 to 1.13). Only the findings from lung cancer were suggestive of a decline in risk with distance, especially in the later period (1982-9). There were 9196 cancer deaths (1981-92) from 0-7.5 km (O/E 1.04; 95% CI 1.02 to 1.06) and 308 from 0-1 km (O/E 1.24; 1.11 to 1.39); and 25507 non-cancer deaths (O/E 1.02; 1.01 to 1.04) from 0-7.5 km and 745 (O/E 1.14; 1.06 to 1.22) from 0-1 km. There was evidence of a decline in mortality with distance for all cancers combined, lung cancer (P = 0.001 for each), and colorectal cancer (P < 0.05), and also for non-cancers (P = 0.001). Proportional mortality analyses suggested a decline in risk with distance for lung cancer (P = 0.003) but not for all cancers or the site specific cancers examined. There was no evidence of an excess in the incidence or mortality from brain cancer. For cancer mortality in the inner-most wards, the findings were, for the most part, well within the range of variation across the region as a whole. CONCLUSIONS: The study provides limited and inconsistent evidence for a localised excess of cancer in the vicinity of the PBI plant. At present, further investigation does not seem warranted other than continued surveillance of mortality and cancer incidence in the locality.  相似文献   
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This paper raises a number of issues in the assessment of quality of provision for pre-school children before comparing the quality of provision offered by community nurseries to that offered by traditional nursery schools. Quality at all locations was assessed using the Harms and Clifford Early Childhood Rating Scale and was found in each case to be at the good to excellent end of the range. Quality varied over time and between locations although all showed improvements by the third and final rating. It is possible to conclude that the community nursery model can provide an environment of comparable quality to that experienced in traditional nursery schools. It was also possible to conclude that quality is vulnerable to internal and external pressures and that monitoring quality can also have the effect of promoting quality when staff are able to respond to feedback from ratings.  相似文献   
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BACKGROUND: The British Journal of General Practice (BJGP) is the leading primary care journal in the world. By impact factor, it ranks 24th of all medical journals. However, despite major changes in the journal since its inception in 1954, there have been no published readership surveys since a limited report in 1969. AIM: To canvass members of the Midland Faculty and to add to the debate about the future of the BJGP. METHOD: A postal questionnaire was sent to a random sample of 299 members, fellows and associates of the Midland Faculty asking for their views about the BJGP. RESULTS: Two hundred replies were received (a response rate of 67%). The median year of qualification of responders was 1981, and 32 (16%) held academic posts. Ninety-nine (49%) disagreed with the present format of the BJGP, which compared poorly with the British Medical Journal (BMJ) in simple rank order of importance. Readership was equal to that of the BMJ (93% reading it within 28 days of arrival), but fewer people read it within a week of receiving it. The most popular sections were the editorials, original articles and letters; least popular were the book reviews and the pull-out magazine, Connection. All sections were rated excellent to average. Readers wished for an expansion of the BJGP to include clinical reviews, medical politics and humorous pieces. Most responders felt that Connection should remain separate. There was dissatisfaction with the delay between submission and publication of original articles, particularly among the academic general practitioners (GPs). Academics and fundholders did not differ from other readers in their views of the content or style of the BJGP. Half of the responders stated that the BJGP should be self-financing and should be open to more advertising. Responders' free comments largely related to improving the style of articles and expanding the BJGP. CONCLUSION: There is a view that the present BJGP is not relevant to the non-academic GP. This is probably due to style rather than content. Simple comparisons with a weekly multi-disciplinary journal may not be valid. The style could be updated to improve retention of information and to highlight areas of particular relevance. Readers are satisfied with the core content of the BJGP but want it to expand to include humour, clinical reviews and medical politics, for example. There is no evidence that the BJGP is more appealing to the academic GP. This study supports an expanded BJGP with an improved style.  相似文献   
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In search of genes possibly involved in the regulation of hindbrain segmentation, we have isolated mouse cDNA clones corresponding to putative protein kinase genes by polymerase chain reaction amplification of cDNA from 9.5-day-old embryo hindbrains. In situ hybridization analysis revealed that one of these genes, Sek, was expressed in an alternating segment-restricted pattern in the developing hindbrain. Isolation and analysis of Sek cDNAs covering the entire coding sequence indicated that Sek encoded a putative receptor protein tyrosine kinase, belonging to the Eph family. These data are consistent with a role of the Sek gene product in a signal transduction process involved in pattern formation in the hindbrain.  相似文献   
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Summary This paper reports the 8-year results of comparing the use of two types of adjuvant chemotherapy following involved field radiotherapy for clinical stages I and II high-grade non-Hodgkin's lymphoma. Twenty-four patients received 6 weeks of VAP plus 2 years of oral maintenance chemotherapy, and 30 had six cycles of CMOPP. Four patients were not in complete remission at completion of i. v. chemotherapy (CR rate 91%). Ten patients (18.5%) have relapsed (VAP/M=5; CMOPP=5), with only two of these remaining alive, both of them being disease free. There have been three deaths from intercurrent causes, one from malignant melanoma and the other two from myocardial infarction. The relapse-free survivals at 2, 5 and 8 years were 80%, 76% & 76% respectively. The overall survivals at the same time points were 86%, 72% & 68%. There were no significant differences in either relapse-free or overall survival for either of the two treatment groups. The shorter period of weekly intravenous chemotherapy (VAP/M) was better tolerated than 36 weeks of CMOPP, and the former appears to produce equivalent results.  相似文献   
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