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31.
全球饲料业每年用在调味剂上的花费大约为一亿五千万欧元. 用在调味剂上的花费,大约一半是用在幼猪日粮的.幼猪若能在这一关键阶段内增加食欲,就可减轻其断奶后应激综合征,因为断奶后离开母猪、运送去新猪舍、建立新秩位而等都会对仔猪产生应激,尤其可减轻因日粮改变而产生的应激.  相似文献   
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OBJECTIVE: To determine expression of a transforming gene (E5) of bovine papillomavirus in sarcoids, other tumors, and normal skin samples collected from horses with and without sarcoids. SAMPLE POPULATION: 23 sarcoids and 6 samples of normal skin obtained from 16 horses with sarcoids, 2 samples of normal skin and 2 papillomas obtained from horses without sarcoids, and 1 papilloma obtained from a cow. PROCEDURE: Protein was extracted from tissue samples collected from horses and incubated with agarose beads covalently coupled to Staphylococcus aureus protein A and an anti-E5 polyclonal antibody. Following incubation, proteins were eluted from the beads and electrophoresed on a 14% polyacrylamide gel and transferred to a polyvinylidene difluoride membrane. The E5 protein was detected by use of western blot analysis, using a chemiluminescence detection system. RESULTS: All 23 sarcoids had positive results for expression of E5 protein. Quantity of viral protein appeared to vary among sarcoids. All other tissues examined had negative results for E5 protein. Highest expression for E5 protein was observed in biologically aggressive fibroblastic variants of sarcoids, compared with expression in quiescent tumors. CONCLUSIONS AND CLINICAL RELEVANCE: This study documented that activation and expression of the E5 gene is evident in sarcoids obtained from horses. These data support the conclusion that infection with bovine papillomavirus is important in the initiation or progression of sarcoids in horses. Treatment strategies designed to increase immune recognition of virally infected cells are warranted.  相似文献   
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The objectives of this study were to identify and quantify lipid classes extracted from the stalk, leaves, and the whole kernels of nine different sorghum parent lines. All extractions were performed with a Soxtec using n-hexane as the extraction solvent. Analytical methods including high-performance liquid chromatography (HPLC), gas chromatography (GC), and thin-layer chromatography (TLC) were used to identify and quantify the extracted lipid classes: triacylglycerides (TAG), diglycerides (DG), policosanols (PA), free sterols (FS), phytosterols (PS), free fatty acids (FFA), tocopherols (T), and fatty aldehydes. Overall, extracts from the leaves had higher amounts of soluble matter. Extracts from leaves contained more alcohols and sterols, whereas extracts from the stalks and the whole kernels contained the greatest amount of free fatty acids and fatty aldehydes, respectively. Trace amounts of tocopherol were detected by HPLC in all 27 samples. The lipid profiles of extracts from the whole kernels, leaves, and stalks from the same plant differed. The lipid profiles of extracts from each anatomical part of the sorghum plant differed between the nine parent lines.  相似文献   
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The enormous progress made in functional magnetic resonance imaging technology allows us to watch our brains engage in complex cognitive and social tasks. However, our understanding of what actually is computed in the underlying cellular networks is hindered by the vast numbers of neurons involved. Here, we describe a vertebrate system, shaped for top speed, in which a complex and plastic decision is performed by surprisingly small circuitry that can be studied at cellular resolution.  相似文献   
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Bovine papillomavirus (BPV-1) contains two independent transforming genes that have been mapped to the E5 and E6 open reading frames (ORF's). The E5 transforming protein was identified by means of an antiserum against a synthetic peptide corresponding to the 20 COOH-terminal amino acids of the E5 ORF. The E5 polypeptide is the smallest viral transforming protein yet characterized; it had an apparent size of 7 kilodaltons. The transforming polypeptide is encoded entirely within the second half of the E5 ORF and its predicted amino acid composition is very unusual; 68% of the amino acids are strongly hydrophobic and 34% are leucine. Cell fractionation studies localized this polypeptide predominantly to cellular membranes.  相似文献   
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G. Melz    R. Schlegel  J. Sybenga 《Plant Breeding》1988,100(3):169-172
The original identification of the chromosomes involved in each of the lines of the act of primary trisomics of winter rye variety ‘Esto’ does not correspond with recent results of gene localization studies. Using known morphological marker genes, N-banding and test crossing with the standard translocation tester set, a more precise identification was possible. In the nomenclature of the Triticinae, the lines can be designated as follows: A = 7R; B = 5R; C = 2R; D = 3R; E = 4R; F = 6R; G = 1R.  相似文献   
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Differential chromosome staining by using the Giemsa C- banding technique and test crosses have revealed rye chroma tin in the hexaploid wheat variety ‘Amigo’ which resulted from wheat crosses with the octoploid triticale ‘Gaucho’. The results demonstrated a pair of translocated wheat chromosomes involving the short arm of rye chromosome 1R and the long arm of the homoeologous wheat chromosome 1A (1Aq/1Rp translocation). The localization of the translocation breakpoint is supposed 10 be within the centromeric region.  相似文献   
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