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排序方式: 共有211条查询结果,搜索用时 359 毫秒
91.
92.
Green DM Werkman M Munro LA Kao RR Kiss IZ Danon L 《Preventive veterinary medicine》2011,99(2-4):225-228
Partitioning of contact networks into communities allows groupings of epidemiologically related nodes to be derived, that could inform the design of disease surveillance and control strategies, e.g. contact tracing or design of 'firebreaks' for disease spread. However, these are only of merit if they persist longer than the timescale of interventions. Here, we apply different methods to identify concordance between network partitions across time for two animal trading networks, those of salmon in Scotland (2002-2004) and livestock in Great Britain (2003-2004). Both trading networks are similar in that they moderately agree over time in terms of their community structures, but this concordance is higher--and therefore community structure is more consistent--when only the 'core' network of nodes involved in trading over the whole time series is considered. In neither case was higher agreement found between partitions close together in time. These measures differ in their absolute values unless appropriate standardisation is applied. Once standardised, the measures gave similar values for both network types. 相似文献
93.
Global mapping of the yeast genetic interaction network 总被引:1,自引:0,他引:1
Tong AH Lesage G Bader GD Ding H Xu H Xin X Young J Berriz GF Brost RL Chang M Chen Y Cheng X Chua G Friesen H Goldberg DS Haynes J Humphries C He G Hussein S Ke L Krogan N Li Z Levinson JN Lu H Ménard P Munyana C Parsons AB Ryan O Tonikian R Roberts T Sdicu AM Shapiro J Sheikh B Suter B Wong SL Zhang LV Zhu H Burd CG Munro S Sander C Rine J Greenblatt J Peter M Bretscher A Bell G Roth FP Brown GW Andrews B Bussey H Boone C 《Science (New York, N.Y.)》2004,303(5659):808-813
A genetic interaction network containing approximately 1000 genes and approximately 4000 interactions was mapped by crossing mutations in 132 different query genes into a set of approximately 4700 viable gene yeast deletion mutants and scoring the double mutant progeny for fitness defects. Network connectivity was predictive of function because interactions often occurred among functionally related genes, and similar patterns of interactions tended to identify components of the same pathway. The genetic network exhibited dense local neighborhoods; therefore, the position of a gene on a partially mapped network is predictive of other genetic interactions. Because digenic interactions are common in yeast, similar networks may underlie the complex genetics associated with inherited phenotypes in other organisms. 相似文献
94.
95.
In populations of Atlantic salmon in sea water, infectious pancreatic necrosis virus (IPNV) could be detected by standard virological culture methods in sonicated kidney homogenates and in mucus samples (gill, skin and rectum) from 14 and nine of 25 fish, respectively, but all fish were positive by virus culture from lysates of kidney macrophages and adherent blood leucocytes. In fish which tested negative for IPNV by the standard method of detection, the virus could be detected using adherent blood leucocytes isolated on a Percoll gradient from as little as 10 microL of blood. The blood sample could be stored for at least 3 days in a heparinized tube on ice before preparing the plastic adherent leucocytes. Furthermore, the latter could be prepared without prior fractionation on Percoll simply by incubating whole blood (33 microL) in cell culture medium (66 microL) in 96-well plates overnight and washing away the non-adherent cells before lysing the adherent cells and inoculation of the lysate onto CHSE-214 cells. This highly sensitive method for detecting IPNV-carriers is therefore very suitable for non-destructive sampling of fish in the field. 相似文献
96.
This review focuses on relevant scientific information regarding the current knowledge of the yellow head complex viruses, yellow head virus and gill‐associated virus. The yellow head complex viruses have been problematic within the aquaculture industry for over 10 years and still retain their research topicality. Presently, there are numerous research papers from different journals covering the identification, disease expression and spread, pathogenesis, detection, morphology, genomic sequence and protein profiles of the yellow head complex viruses. Indeed, there has been no extensive review to compare these studies, and as a corollary, to assess flaws in contemporary research and knowledge. Additionally, the yellow head complex viruses rank within the top four prawn viruses with respect to disease impact and economic loss. This review collectively reports on all the findings and current methods of research and aims to identify weak areas of research where conclusions have been unjustifiably drawn and furthermore to elucidate areas that have a gap of knowledge. 相似文献
97.
Colisa lalia (Ham.) has been used as a model for the development of techniques for induced spawning that are applicable to small teleosts where ovulation requires prolonged exposure to suitable breeding conditions.Human chorionic gonadotrophin (hCG; 4 IU per fish) induced ovulation within 24 hours, whereas homologous pituitary extracts were relatively ineffective. When administered in saline ( 20 g per fish per injection), des-Gly10,[D-Ala6]- LHRH N-ethylamide (LHRHa) was ineffective, but it stimulated ovulation in a proportion of fish when administered ( 1.6 g per fish) as an emulsion in Freund's incomplete adjuvant (FIA). Together, these results suggest that ovulation requires the synthesis as well as the secretion of gonadotrophin in C. lalia.Long-term treatment with thyroid hormones appeared to enhance the ovulatory response to LHRHa in FIA, possibly by effects on the ovary; whereas the various steroids tested were ineffective at the dosages used 相似文献
98.
Protein synthesis in rat liver: influence of amino acids in diet on microsomes and polysomes 总被引:19,自引:0,他引:19
Rats were killed 1 hour after having been fed by stomach tube with amino acid mixtures that were either nutritionally complete or lacked tryptophan. Microsomes isolated from the livers of animals fed the incomplete mixture showed a reduced capacity to incorporate (14)C-leucine in vitro, and polysomes prepared from the same livers showed an increased proportion of monosomes and disomes. Prior treatment with actinomycin D did not prevent these differences in response to the two amino acid mixtures, an indication that synthesis of messenger RNA may not be involved in the cell mechanism which recognizes differences in amino acid pattern. 相似文献
99.
POTENTIAL PASTURE PRODUCTION IN THE UPLANDS OF WALES 总被引:1,自引:0,他引:1
Study of the growth of heavily fertilized swards of S23 perennial ryegrass (Lolium perenne) at a hill and a lowland centre in mid-Wales during 1968–69 demonstrated that lower productivity in the uplands could only be partially attributed to a shorter growing season and poorer summer growth conditions. Comparison of yields with potential transpiration estimates indicated that winter damage had an important bearing on production during the following year. In 1969, the adverse combination of a mild autumn and a severe winter led to a spring tiller density which was less than 25% of normal at the hill centre. With an annual fertilizer input of over 500 kg N/ha (480 lb N/ac) total DM production in 1968 and 1969 was 10.6 and 4.4 t/ha at the upland site compared with 14.8 and 10.1 t/ha in the lowlands (9450, 3920, 13,190 and 9000 lb/ac). 相似文献
100.
C. Brömel R.W. Nelson E.C. Feldman C.J. Munro P.H. Kass A.E. Vico P. Labelle A.J. Conley 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2013,27(1):76-82