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111.
K M Rowan J H Kerr E Major K McPherson A Short M P Vessey 《BMJ (Clinical research ed.)》1993,307(6910):972-977
OBJECTIVES--To describe the extent of variation in the case mix of adult admissions to general intensive care units in Britain and Ireland and investigate the impact of such variation on outcome. DESIGN--Prospective, cohort study of consecutive admissions to intensive care units. SETTING--26 general intensive care units in Britain and Ireland. SUBJECTS--9099 admissions to the intensive care units studied. MAIN OUTCOME MEASURE--Death or survival at discharge before and after adjustment of case mix (age, history of chronic conditions, surgical status, diagnosis, and severity of illness) according to the APACHE II method. RESULTS--Important differences in case mix were found, with large variations between the units. Hospital mortality was significantly associated with most of the case mix factors investigated. CONCLUSIONS--Comparing crude death rates in hospital between intensive care units may be misleading indicators of performance. The collection of data on case mix needs to be standardised and differences in case mix adjusted for when comparing outcome between different intensive care units. 相似文献
112.
Linkage disequilibrium over short physical distances measured in sheep using a high‐density SNP chip
James W. Kijas Laercio Porto‐Neto Sonja Dominik Antonio Reverter Rowan Bunch Russell McCulloch Ben J. Hayes Rudiger Brauning John McEwan the International Sheep Genomics Consortium 《Animal genetics》2014,45(5):754-757
The extent of linkage disequilibrium (LD) between genetic loci has implications for both association studies and the accuracy of genomic prediction. To characterise the persistence of LD in diverse sheep breeds, two SNP genotyping platforms were used. First, existing SNP genotypes from 63 breeds obtained using the ovine SNP50 BeadChip (49 034 loci) were used to estimate LD decay in populations with contrasting levels of genetic diversity. Given the paucity of marker pairs separated by short physical distances on the SNP50 BeadChip, genotyping was subsequently performed for four breeds using the recently developed ovine HD BeadChip that assays approximately 600 000 SNPs with an average genomic spacing of 5 kb. This facilitated a highly accurate estimate of LD over short genomic distances (<30 kb) and revealed LD varies considerably between sheep breeds. Further, sheep appear to contain generally lower levels of LD than do other domestic species, likely a reflection of aspects of their past population history. 相似文献
113.
Derek V. Banthorpe Graham A. Bucknall Jan A. Gutowski Michael G. Rowan 《Phytochemistry》1977,16(3):355-358
Cell-free extracts of Tanacetum vulgare, Artemisia annua, and Santolina chamaecyparissus contain seasonally-dependent enzyme systems that convert IPP4, DMAPP, GPP and NPP into water-soluble products in up to 96% yield. 3-Methyl-3,4-oxidobutan-1-ol; 3-methylbutan-1,3,4-triol; 3,7-dimethyl-6,7-oxido-octa-trans-2-en-1-ol; and 3,7-dimethylocta-trans,trans-2,5-dien-1,7-diol were major products when IPP and GPP respectively were substrates and several other terpene epoxides and their ring-opened products were tentatively identified. 2-CEPA blocked formation of diols from the epoxides. The occurrence of these enzymes accounts for some hitherto puzzling observations that have arisen in studies of monoterpene biosynthesis both in vivo and in vitro. 相似文献
114.
K M Rowan J H Kerr E Major K McPherson A Short M P Vessey 《BMJ (Clinical research ed.)》1993,307(6910):977-981
OBJECTIVES--To compare outcome between intensive care units in Britain and Ireland both before and after adjustment for case mix with the American APACHE II method and to validate the American APACHE II method in Britain and Ireland. DESIGN--Prospective, cohort study of consecutive admissions to intensive care units. SETTING--26 general intensive care units in Britain and Ireland. SUBJECTS--8796 admissions to the study intensive care units. MAIN OUTCOME MEASURE--Death or survival at discharge from intensive care unit and hospital. RESULTS--At discharge from both intensive care unit and hospital there was a greater than twofold variation in crude mortality between the 26 units. After adjustment for case mix, variations in mortality were still apparent. For four intensive care units the observed numbers of deaths were significantly different from the number predicted by the American APACHE II equation. The overall goodness of fit, or predictive ability, of the APACHE II equation for the British and Irish data was good, being only slightly inferior to that obtained when the equation was tested on the data from which it had been derived. When patients were grouped by various factors such as age and diagnosis, the equation did not adjust across the subgroups in a uniform manner. CONCLUSIONS--The American APACHE II equation did not fit the British and Irish data. Use of the American equation could be of advantage or disadvantage to individual intensive care units, depending on the mix of patients treated. 相似文献
115.
Brown, C. J. 1989. Plumages and measurements of the Bearded Vulture in southern Africa. Ostrich 60: 165–171. Four different age classes of the southern African Bearded Vulture Gypaetus barbatus are recognized and their plumages described: juvenile (3–24 months old), immature (24–45 months), subadult (45–60 months) and adult (60+ months). There was no significant difference in size between adult male and female birds. Adults were larger than juvenile birds in bill width, beard length, wingspan and mass, and had a higher aspect ratio and wing loading, while juvenile birds were larger than adults in the length of their outer rectrices, tail area, wing breadth and wing area. These features are considered to be adaptive to young birds inexperienced in flying. Immature and subadult birds were intermediate in size between juveniles and adults. Bearded Vultures differ from other large raptors in two sets of physical characteristics, (a) those adapted to cold, mountainous habitat, e.g. feathered head and face, unusually long wings, a high aspect ratio and a particularly long tail, and (b) those adapted to their diet of mainly bones, e.g. wide gape, beard and relatively long talons for carrying food. 相似文献
116.
Medicinal mushrooms: a rapidly developing area of biotechnology for cancer therapy and other bioactivities 总被引:1,自引:0,他引:1
Historically, medicinal mushrooms (basidiomycetes) have been shown to have profound health promoting benefits and recent studies, which are reviewed here, are now confirming their medical efficacy and identifying many of the bioactive molecules. Methods of large-scale cultivation by solid substrate and liquid culture fermentations are also briefly described. 相似文献
117.
The inhibitory specificity of a protein from potato tubers that inhibits cysteine proteinases (potato cysteine proteinase inhibitor, PCPI) has been compared with that of chicken egg-white cystatin. Most proteinases that are inhibited by cystatin were also inhibited by PCPI, but the potato inhibitor inhibited stem bromelain and fruit bromelain, which are not inhibited by cystatin, and for which no protein inhibitor of comparable potency has previously been described. In contrast, papaya proteinase IV was unaffected by PCPI as it is by the cystatins, and the exopeptidase, dipeptidyl peptidase I, is inhibited by cystatins, but was unaffected by PCPI. The differences in inhibitory specificity between these proteins may well reflect differences between superfamilies of cysteine proteinase inhibitors. 相似文献
118.
Daniel C Lopes Rowan O Martin Mohamed Henriques Hamilton Monteiro Aissa Regalla Quintino Tchantchalam 《Ostrich》2018,89(1):33-40
Timneh Parrots Psittacus timneh are endemic to the moist forests of West Africa. Concerns over rapid declines in populations due to overharvesting for the pet trade and forest loss prompted the species’ categorisation as Endangered on the IUCN Red List of Threatened Species in 2016. Despite these threats, few data exist on their biology in the wild, impeding the development of effective conservation initiatives to protect populations. One of the few recorded breeding sites for this species occurs in the Bijagós Archipelago in Guinea-Bissau, where chicks have been historically harvested from nests and forest clearance for agriculture is common. We investigated the breeding ecology of Timneh Parrots in the Bijagós Archipelago focusing on two islands that harbour the densest populations. Specifically, we describe nest-site characteristics, breeding phenology and reproductive productivity. Timneh Parrots were found to use secondary nest cavities in 17 species of trees, predominantly nesting in trees between 20 m and 50 m in height. Nest cavities were generally aggregated, with a density of up to 14 nests ha?1 in some areas, although nests also occurred in isolated large trees. The distribution of nests likely reflected a heterogeneous distribution of large trees containing suitable nest cavities, emphasising the importance of protecting mature trees. Nesting efforts were initiated between early January until late March, suggesting that nest surveillance efforts to deter poaching can be efficiently focused at a small number of key sites during February to May each year, when fledgling chicks are most likely to be present. These data further suggest that the population may be limited by the availability of suitable nest cavities and that the installation of artificial nest cavities could help increase the breeding population. 相似文献
119.
120.
Rubisco in marine symbiotic dinoflagellates: form II enzymes in eukaryotic oxygenic phototrophs encoded by a nuclear multigene family. 总被引:8,自引:0,他引:8 下载免费PDF全文
Genes encoding ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) were cloned from dinoflagellate symbionts (Symbiodinium spp) of the giant clam Tridacna gigas and characterized. Strikingly, Symbiodinium Rubisco is completely different from other eukaryotic (form I) Rubiscos: it is a form II enzyme that is approximately 65% identical to Rubisco from Rhodospirillum rubrum (Rubisco forms I and II are approximately 25 to 30% identical); it is nuclear encoded by a multigene family; and the predominantly expressed Rubisco is encoded as a precursor polyprotein. One clone appears to contain a predominantly expressed Rubisco locus (rbcA), as determined by RNA gel blot analysis of Symbiodinium RNA and sequencing of purified Rubisco protein. Another contains an enigmatic locus (rbcG) that exhibits an unprecedented pattern of amino acid replacement but does not appear to be a pseudogene. The expression of rbcG has not been analyzed; it was detected only in the minor of two taxa of Symbiodinium that occur together in T. gigas. This study confirms and describes a previously unrecognized branch of Rubisco's evolution: a eukaryotic form II enzyme that participates in oxygenic photosynthesis and is encoded by a diverse, nuclear multigene family. 相似文献