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71.
Henri CM Heuven Rik HJ van Wijk Bert Dibbits Tony A van Kampen Egbert F Knol Henk Bovenhuis 《遗传、选种与进化》2009,41(1):4
Quantitative trait loci (QTL) affecting carcass and meat quality located on SSC2 were identified using variance component methods. A large number of traits involved in meat and carcass quality was detected in a commercial crossbred population: 1855 pigs sired by 17 boars from a synthetic line, which where homozygous (A/A) for IGF2. Using combined linkage and linkage disequilibrium mapping (LDLA), several QTL significantly affecting loin muscle mass, ham weight and ham muscles (outer ham and knuckle ham) and meat quality traits, such as Minolta-L* and -b*, ultimate pH and Japanese colour score were detected. These results agreed well with previous QTL-studies involving SSC2. Since our study is carried out on crossbreds, different QTL may be segregating in the parental lines. To address this question, we compared models with a single QTL-variance component with models allowing for separate sire and dam QTL-variance components. The same QTL were identified using a single QTL variance component model compared to a model allowing for separate variances with minor differences with respect to QTL location. However, the variance component method made it possible to detect QTL segregating in the paternal line (e.g. HAMB), the maternal lines (e.g. Ham) or in both (e.g. pHu). Combining association and linkage information among haplotypes improved slightly the significance of the QTL compared to an analysis using linkage information only. 相似文献
72.
分子系统发育对中国芸香科分类的贡献 总被引:2,自引:0,他引:2
The treatment of Rutaceae in the Chinese flora chose to follow Engler in recognizing Rutoideae and Toddalioideae as two separate subfamilies. Morphological and chemical comparisons, however, suggested grouping those two subfamilies in one subfamily, Rutoideae. This move has received support from molecular phylogenetic analyses, which also showed that the Chinese taxa in Euodia should be placed in Tetradium and Melicope following Hartley. Investigations into the chemistry and molecular phylogeny of Murraya also indicated that the species in the section Bergera without yuehchukene should be removed from Murraya. These findings clearly show the value of molecular cladistics to the taxonomy of Rutaceae in China and also directions for further investigations. Key words Bergera, Euodia, Melicope, Murraya, Rutaceae, Rutoideae, Tetradium, Toddalioideae. 相似文献
73.
天花粉蛋白的定点聚乙二醇修饰 总被引:3,自引:0,他引:3
用一种定点修饰天花粉蛋白(trichosanthin,TCS)的方法,将聚乙二醇(PEG)偶联到预先选定的位点.利用nTCS无半胱氨酸(Cys)残基这一特点,通过定点突变将一个Cys残基引入TCS以取代第7位的丝氨酸(Ser)残基.然后,与巯基反应的PEG-m aleim ide 即可偶联到新引入的Cys 残基上.经纯化得到均一的PEG-TCS复合物,在SDS-PAGE上显示一条区带,表观分子量为38 kD.复合物的体外致核糖体失活活性降低了6倍,但其体内引产活性与nTCS相同.定点PEG修饰方法为改造TCS提供了新途径. 相似文献
74.
A model based on the concept of the circle of influence of a plant is used to estimate the relationship between yield and area/plant for tobacco crops with gaps in stand. The model predicts the average yield of plants in any configuration that includes missing plants and is used to predict the economic consequences of loss in stand from pest or other damage. 相似文献
75.
76.
Martinus AM van Boekel Erik R Vossenaar Frank HJ van den Hoogen Walther J van Venrooij 《Arthritis research & therapy》2001,4(2):87
The diagnosis of rheumatoid arthritis (RA) is primarily based on clinical symptoms, so it is often difficult to diagnose RA in very early stages of the disease. A disease-specific autoantibody that could be used as a serological marker would therefore be very useful. Most autoimmune diseases are characterized by a polyclonal B-cell response targeting multiple autoantigens. These immune responses are often not specific for a single disease. In this review, the most important autoantibody/autoantigen systems associated with RA are described and their utility as a diagnostic and prognostic tool, including their specificity, sensitivity and practical application, is discussed. We conclude that, at present, the antibody response directed to citrullinated antigens has the most valuable diagnostic and prognostic potential for RA. 相似文献
77.
78.
van Can HJ te Braake HA Bijman A Hellinga C Luyben KC Heijnen JJ 《Biotechnology and bioengineering》1999,62(6):666-680
There is a need for efficient modeling strategies which quickly lead to reliable mathematical models that can be applied for design and optimization of (bio)-chemical processes. The serial gray box modeling strategy is potentially very efficient because no detailed knowledge is needed to construct the white box part of the model and because covenient black box modeling techniques like neural networks can be used for the black box part of the model. This paper shows for a typical biochemical conversion how the serial gray box modeling strategy can be applied efficiently to obtain a model with good frequency extrapolation properties. Models with good frequency extrapolation properties can be applied under dynamic conditions that were not present during the identification experiments. For a given application domain of a model, this property can be used to considerably reduce the number of identification experiments. The serial gray box modeling strategy is demonstrated to be successful for the modeling of the enzymatic conversion of penicillin G In the concentration range of 10-100 mM and temperature range of 298-335 K. Frequency extrapolation is shown by using only constant temperatures in the (batch) identification experiments, while the model can be used reliable with varying temperatures during the (batch) validation experiments. No reliable frequency extrapolation properties could be obtained for a black box model, and for a more knowledge-driven white box model reliable frequency extrapolation properties could only be obtained by incorporating more knowledge in the model. Copyright 1999 John Wiley & Sons, Inc. 相似文献
79.
80.
Unsmoked Wiltshire bacon was produced with and without nitrate and with different concentrations of nitrite. Micrococci, Moraxella spp. and Moraxella -like organisms were the most common bacteria on the bacon after maturation when there was little difference between the microflora of the various back bacon. Collar bacon cured without nitrate carried much higher numbers of Moraxella spp. than that cured with nitrate. Micrococci and lactic acid bacteria usually predominated after vacuum-packed storage. Inclusion of nitrate in the cure increased the numbers of micrococci but did not reduce stability on storage. The highest numbers of lactic acid bacteria were present on bacon containing the lowest initial concentration of nitrite (34 parts/106 ) and it is thought that nitrite may delay the souring which these bacteria cause in vacuum-packed bacon. 相似文献