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101.
Zdobnov EM von Mering C Letunic I Torrents D Suyama M Copley RR Christophides GK Thomasova D Holt RA Subramanian GM Mueller HM Dimopoulos G Law JH Wells MA Birney E Charlab R Halpern AL Kokoza E Kraft CL Lai Z Lewis S Louis C Barillas-Mury C Nusskern D Rubin GM Salzberg SL Sutton GG Topalis P Wides R Wincker P Yandell M Collins FH Ribeiro J Gelbart WM Kafatos FC Bork P 《Science (New York, N.Y.)》2002,298(5591):149-159
Comparison of the genomes and proteomes of the two diptera Anopheles gambiae and Drosophila melanogaster, which diverged about 250 million years ago, reveals considerable similarities. However, numerous differences are also observed; some of these must reflect the selection and subsequent adaptation associated with different ecologies and life strategies. Almost half of the genes in both genomes are interpreted as orthologs and show an average sequence identity of about 56%, which is slightly lower than that observed between the orthologs of the pufferfish and human (diverged about 450 million years ago). This indicates that these two insects diverged considerably faster than vertebrates. Aligned sequences reveal that orthologous genes have retained only half of their intron/exon structure, indicating that intron gains or losses have occurred at a rate of about one per gene per 125 million years. Chromosomal arms exhibit significant remnants of homology between the two species, although only 34% of the genes colocalize in small "microsyntenic" clusters, and major interarm transfers as well as intra-arm shuffling of gene order are detected. 相似文献
102.
Epinephrine and norepinephrine condensed with acetaldehyde or with formaldehyde in dilute aqueous solution at neutral pH and room temperature to form 1,2,3,4-tetrahydroiso-quinoline alkaloids. Similar condensation reactions occurred in cow adrenal glands perfused with dilute aldehyde solutions at 37 degrees C. Biosynthesis of these alkaloids in vivo could play a role in altering an individual's behavior during and after the ingestion of alcohol. 相似文献
103.
Ruiz-Matute AI Brokl M Sanz ML Soria AC Côté GL Collins ME Rastall RA 《Journal of agricultural and food chemistry》2011,59(8):3693-3700
The selective fermentation by human gut bacteria of gluco-oligosaccharides obtained from the reaction between the glucosyl group of sucrose and cellobiose, catalyzed by dextransucrases (DSR) from Leuconostoc mesenteroides , has been evaluated. Oligosaccharides were fractionated according to their molecular weight, and their effect on the growth of different bacterial groups was studied. To determine the structure (position and configuration of glycosidic linkages)-function relationship, their properties were compared to those of DSR maltose acceptor products (DSRMal) and of recognized prebiotic carbohydrates (fructo-oligosaccharides, FOS). Cellobiose acceptor products (DSRCel) showed bifidogenic properties similar to those of FOS. However, no significant differences related to molecular weight or isomeric configurations were found for DSRCel and DSRMal products. 相似文献
104.
Wylie CE Collins SN Verheyen KL Richard Newton J 《Veterinary journal (London, England : 1997)》2011,189(3):248-256
Equine laminitis is a highly debilitating disease of the foot. Despite its perceived importance, epidemiological characteristics are poorly understood and the true frequency of the disease remains unclear. The objective of this study was to retrospectively assess previous research to identify publications which provide the best evidence of the frequency of naturally-occurring equine laminitis. A systematic review of English language publications was conducted using MEDLINE (1950–2010), CAB Direct (1910–2010) and IVIS (1997–2010). Additional publications were included by searching bibliographies. Search terms included laminitis, equine, frequency, prevalence and incidence. Studies that allowed frequency estimations to be made for naturally-occurring equine laminitis were included. Information was extracted using predefined data fields, including 13 study quality indicators.Sixty-nine publications were appraised. Ten were considered to provide the most reliable information, estimating the frequency of equine laminitis ranging from 1.5% to 34%. Previous publications estimating laminitis frequency were generally poor quality. Laminitis frequency varied across publications however the publications included in this review focussed on many of the different underlying laminitis aetiologies and comparison of the frequencies between groups would be inappropriate. High-quality evidence-based studies are needed to estimate the true disease frequency in different equine populations. 相似文献
105.
K. Collins 《Geoderma》1983,30(1-4):243-252
Specimen preparation for the scanning electron microscopy of engineering soils is vitally important. The usefulness of critical point drying is assessed on the basis of macroscopic and microscopic data obtained from the critical point drying and the air drying of several natural undisturbed soft clays.
It is emphasised that scanning electron microscopy can play a valuable reconnaissance role, thus providing an indication of the broad character of the soil microfabric, over a wide range of magnification, which aids in the selection of the appropriate programme and methods of quantification.
It is also demonstrated that scanning electron microscopy observations are extremely useful in the interpretation of, and for providing the very necessary background to, quantitative data such as that yielded by optical thin section and mercury porosimetry studies. 相似文献
106.
Yu K Hamilton-Kemp TR Archbold DD Collins RW Newman MC 《Journal of agricultural and food chemistry》2000,48(2):413-417
Volatile compounds emitted by cultures of two strains of the pathogenic bacterium Escherichia coliO157:H7 and a nonpathogenic strain of E. coli were trapped on Super-Q porous polymer and identified by GC-MS. The predominant compound produced by all three strains was indole with lesser amounts of other components including methyl ketones, 2-heptanone, 2-nonanone, 2-undecanone, and 2-tridecanone. The vapor-phase profiles of these strains were similar for most chemicals identified but differed with regard to ketones. Strawberry fruit was shown to be a suitable host for E. coli O157:H7 with the population of the bacterium either increasing or remaining stable after 3 days depending on inoculation level. Headspace analysis of the volatile compounds from inoculated fruit yielded no detectable quantity of indole. Strawberry fruit readily absorbed indole and other volatile compounds produced by the bacteria and in some cases metabolized the compounds to new volatile products. Thus, headspace "marker" compounds indicating possible bacterial contamination of fruit were largely removed from the vapor phase by the strawberries. 相似文献
107.
W H Newsome P G Collins 《Journal of the Association of Official Analytical Chemists》1987,70(6):1025-1027
Enzyme-linked immunosorbent assays were developed for benomyl as its decomposition product, methyl 2-benzimidazole carbamate, and thiabendazole in foods. Immunogens consisting of human serum albumin coupled to 2-succinamidobenzimidazole or 2-(2'-succinamido-4'-thiazolyl)benzimidazole were used in rabbits to raise antisera that were specific for the respective fungicides. Lower limits of quantitation of 0.35 ppm for benomyl and 0.03 ppm for thiabendazole were established without cleanup of the ethyl acetate extract. Recoveries of benomyl from 3 crops spiked at 0.5 to 10 ppm averaged 89% (range 73-109%) and of thiabendazole from 5 crops spiked at 0.1 to 2.0 ppm were 93% (range 81-105%). 相似文献
108.
109.
W H Newsome P Collins D Lewis 《Journal of the Association of Official Analytical Chemists》1986,69(4):591-593
Alachlor [2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide] was determined by hydrolysis to 2,6-diethylaniline with 6N HCl and quantitation of the heptafluorobutyryl derivative by gas chromatography with electron capture detection. 2,6-Diethylaniline was isolated from the hydrolysate by steam distillation, derivatized with heptafluorobutyric anhydride, and the derivative was purified by chromatography on silicic acid with 60% toluene in hexane as eluant. Recoveries from potatoes, soybeans, and corn spiked at levels from 3 to 26 ppb averaged 81, 90, and 96% respectively. 相似文献
110.
OBJECTIVES: To identify and characterise dietary patterns in a middle-aged Irish population sample and study associations between these patterns, sociodemographic and anthropometric variables and major risk factors for cardiovascular disease. DESIGN: A cross-sectional study. SUBJECTS AND METHODS: A group of 1473 men and women were sampled from 17 general practice lists in the South of Ireland. A total of 1018 attended for screening, with a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and provided a fasting blood sample for glucose, lipids and homocysteine. Dietary intake was assessed using a standard food-frequency questionnaire adapted for use in the Irish population. The food-frequency questionnaire was a modification of that used in the UK arm of the European Prospective Investigation into Cancer study, which was based on that used in the US Nurses' Health Study. Dietary patterns were assessed primarily by K-means cluster analysis, following initial principal components analysis to identify the seeds. RESULTS: Three dietary patterns were identified. These clusters corresponded to a traditional Irish diet, a prudent diet and a diet characterised by high consumption of alcoholic drinks and convenience foods. Cluster 1 (Traditional Diet) had the highest intakes of saturated fat (SFA), monounsaturated fat (MUFA) and percentage of total energy from fat, and the lowest polyunsaturated fat (PUFA) intake and ratio of polyunsaturated to saturated fat (P:S). Cluster 2 (Prudent Diet) was characterised by significantly higher intakes of fibre, PUFA, P:S ratio and antioxidant vitamins (vitamins C and E), and lower intakes of total fat, MUFA, SFA and cholesterol. Cluster 3 (Alcohol & Convenience Foods) had the highest intakes of alcohol, protein, cholesterol, vitamin B(12), vitamin B(6), folate, iron, phosphorus, selenium and zinc, and the lowest intakes of PUFA, vitamin A and antioxidant vitamins (vitamins C and E). There were significant differences between clusters in gender distribution, smoking status, physical activity, body mass index, waist circumference and serum homocysteine concentrations. CONCLUSION: In this general population sample, cluster analysis methods yielded two major dietary patterns: prudent and traditional. The prudent dietary pattern is associated with other health-seeking behaviours. Study of dietary patterns will help elucidate links between diet and disease and contribute to the development of healthy eating guidelines for health promotion. 相似文献