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排序方式: 共有269条查询结果,搜索用时 46 毫秒
41.
N. H. Hills J. J. Pflug K. Jeyasingh Lynn Boardman J. S. Calnan 《BMJ (Clinical research ed.)》1972,1(5793):131-135
A consecutive, randomly allocated, controlled clinical trial of the prophylactic effect of intermittent pneumatic compression of the calf on the incidence of postoperative deep vein thrombosis showed that in patients without malignant disease there was a highly significant reduction in the incidence of thrombosis. In patients with malignant disease the incidence of thrombosis was higher than in those without, and there was no reduction in incidence by the application of intermittent compression. In the absence of malignant disease, severity of operation and the age of the patient were the most significant aetiological factors. We found no relation between the incidence of deep venous thrombosis and obesity, length of preoperative stay, location of hospital, or duration of anaesthesia. We suggest that intermittent pneumatic compression as used in this trial is a safe, effective, and extremely practical method of preventing postoperative deep vein thrombosis in patients not suffering from malignant disease. 相似文献
42.
Ammonia production by pathogenic bacteria 总被引:6,自引:0,他引:6
Hills GM 《The Biochemical journal》1940,34(7):1057-1069
43.
M. Hills 《American journal of physical anthropology》1982,59(3):321-322
Jungers and German (1981) found differences when they compared 1) coefficients of allometry from bivariate plots of log measurements versus log body weight with 2) those coefficients from the first principal component of the log measurements excluding body weight. It is argued here that an arbitrary choice of unit for “internal size” is all that separates these coefficients. When the unit is chosen to make internal size isometric with body weight the coefficients agree rather well. 相似文献
44.
We describe a new, morphologically distinct species of Penion found off the Three Kings Islands, Middlesex and King banks, and Cape Reinga, in the far north of New Zealand.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:573BCBA0-1FFB-490D-8AEF-AC156354E48B 相似文献
45.
Cell wall assembly in vitro from Chlamydomonas reinhardi 总被引:1,自引:0,他引:1
G. J. Hills 《Planta》1973,115(1):17-23
Summary The conditions for in vitro dissociation and reassembly of the cell wall of Chlamydomonas reinhardi have been investigated. The cell wall dissociates in aqueous 8 M lithium chloride to two homogeneous components (6.8 S20w and 9.3 S20w)and dialysis of the cell wall subunits against water causes reassembly of a product having the same overall morphology and chemically similar to the original cell walls. Cell wall subunits in 8 M lithium chloride alone do not reassemble on dialysis against water to form cell walls but a nucleation centre has to be provided. 相似文献
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47.
Andy F.S. Taylor Alan E. Hills Giampaolo Simonini Ernst E. Both Ursula Eberhardt 《Mycological Research》2006,110(3):276-287
Identification of species within the boletoid genus Xerocomus has relied heavily upon the macromorphological features of the basidiomes. However, the phenotypic plasticity of these features has resulted in considerable confusion over the delimitation of taxa. In this study, we examined collections attributed to the X. subtomentosus complex in Europe using morphological and rDNA–ITS sequence data. In total, 45 European collections from a wide range of geographical areas and ecological conditions were included in the study. In spite of detecting considerable genetic variation, even within individual basidiomes of X. subtomentosus, molecular data, spore size, flesh colour, and the colour of the basal mycelium allow for the recognition of four distinct taxa: two correspond to X. subtomentosus (13 collections) and X. ferrugineus (20); one X. chrysonemus sp. nov. (10), to date only found in the UK, is described as new; and the existence of another taxon (two; Italy and UK) is noted but left undescribed owing to lack of material. Eight collections from North America were also included in the study, from which two taxa with a close affinity to X. ferrugineus were recognised. 相似文献
48.
It is widely recognized that the nature and characteristics of transport across eukaryotic membranes are so complex as to defy intuitive understanding. In these circumstances, quantitative mathematical modeling is an essential tool, both to integrate detailed knowledge of individual transporters and to extract the properties emergent from their interactions. As the first, fully integrated and quantitative modeling environment for the study of ion transport dynamics in a plant cell, OnGuard offers a unique tool for exploring homeostatic properties emerging from the interactions of ion transport, both at the plasma membrane and tonoplast in the guard cell. OnGuard has already yielded detail sufficient to guide phenotypic and mutational studies, and it represents a key step toward ‘reverse engineering’ of stomatal guard cell physiology, based on rational design and testing in simulation, to improve water use efficiency and carbon assimilation. Its construction from the HoTSig libraries enables translation of the software to other cell types, including growing root hairs and pollen. The problems inherent to transport are nonetheless challenging, and are compounded for those unfamiliar with conceptual ‘mindset’ of the modeler. Here we set out guidelines for the use of OnGuard and outline a standardized approach that will enable users to advance quickly to its application both in the classroom and laboratory. We also highlight the uncanny and emergent property of OnGuard models to reproduce the ‘communication’ evident between the plasma membrane and tonoplast of the guard cell. 相似文献
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