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81.
Population-wide analysis of a QTL affecting milk-fat production in the Israeli Holstein population 总被引:6,自引:0,他引:6
A population-wide linkage disequilibrium on bovine chromosome 14 between microsatellite ILSTS039 and DGAT1, a putative quantitative trait locus affecting milk production traits, was found in the Israeli Holstein population. A total of 394 bulls were genotyped for both DGAT1 and ILSTS039, and 1747 cows were genotyped for ILSTS039. The ILSTS039 allele termed "225," and the DGAT1 K allele (substitution of a lysine residue with alanine), were associated with decreased milk production, and increased fat production and fat and protein percent. The number of 225 ILSTS039 and K DGAT1 alleles per individual were the same for 80% of the bulls genotyped. From the effects associated with cows homozygous for the 225 allele, the effect of the quantitative trait locus appears to be approximately codominant. The substitution effect was 0.16% fat. Genotype probabilities for the quantitative gene were determined for the entire Israeli Holstein milk-recorded population, including 507,725 cows and 1442 bulls, using segregation analysis. Overall frequency of the allele that increased fat percent was 8.9% in cows and 15.5% in bulls. The frequency of this allele decreased from 1981 until 1990, from 15 to 5%, and since has increased to 10%. The effects estimated on the population-wide analyses of both cows and bulls were similar to the effect associated with DGAT1 in the daughters of genotyped bulls. Modified animal model evaluations were computed for the entire population with the effect of this gene included in the model. The correlations between the modified and standard animal model evaluations for all traits were > 0.99. 相似文献
82.
Metzger A.G. Ramanathan R. Jiang Li Hsiang-Chih Sun Cismaru C. Hongxiao Shao Rushing L. Weller K.P. Ce-Jun Wei Yu Zhu Klimashov A. Tkachenko Y.A. Bin Li Zampardi P.J. 《Solid-State Circuits, IEEE Journal of》2007,42(10):2137-2148
The last decade has seen GaAs HBTs emerge as the dominant technology in wireless handset power amplifiers. Modern application requirements and size limitations have driven industry leaders towards the co-integration of depletion mode n-FET and GaAs HBT. The merger of Bipolar and FET, or BiFET, gives an additional degree of freedom in the design of advanced power amplifiers independent of a silicon controller. This paper provides an overview of the various techniques that can be used to join the two device technologies and then shows how a merged epitaxial structure, where an FET is formed in the emitter layers of an HBT, combines functional versatility with the high volume manufacturability needed to supply millions of power amplifiers at low cost. A large-signal model of the FET structure is developed which takes into account the unique physics and geometries of the device, including voltage-dependant parameters and charges on all four electrical terminals. Specific handset applications that can benefit or be enabled by BiFET are presented, such as on-off switching, low voltage bias controllers , Auto-Bias power amplifiers, and bias circuits with low or no voltage reference. When npn-only bias circuitry is limited to low voltage reference levels, HBT power amplifiers with BiFET bias stages are shown to have superior RF performance to their npn-only counterparts. 相似文献
83.
Vicki Schlegel Richard Zbasnik Tammy Gries Bo Hyun Lee Timothy Carr Ji-Young Lee Curtis Weller Susan Cuppett 《Food chemistry》2011
The floss and oil of the common milkweed (Asclepias syriaca L.) seeds are currently used to produce comforters/pillows and skin care products, respectively. As an outcome of these products, copious quantities co-products (pressed seed meal and pod biomass) are disposed of each year despite the presence of potential health benefitting lipids. The objective of this project was to determine the feasibility of developing the lipid fraction from of these co-products for the fast growing dietary human health market. Although certain types of lipids were affected by the extraction solvent used (hexane and diethyl ether) as were overall amounts, analysis of the each extract showed novel lipid profiles with several potential health benefitting agents present at levels comparable to or exceeding those present in other typically consumed dietary oils or food systems (vitamin E, carotenoids, sterols and unsaturated free fatty acids, particularly the both omega 7-fatty acids). 相似文献
84.
85.
C Teinturier MS Pauchard L Brugières P Landais JL Chaussain PF Bougnères 《Canadian Metallurgical Quarterly》1999,32(2):106-111
BACKGROUND: A retrospective study of 54 children was undertaken to define the clinical presentation and secretory patterns of adrenal tumors and to evaluate the outcome of surgical resection and medical therapy. PROCEDURES: Different factors were studied in univariate and multivariate analysis by using the Cox proportional hazard model. RESULTS: Median age at diagnosis was 4 years. Boys and girls were affected equally. The disease was revealed by virilization (61%) or by a palpable mass (39%) with a 0.1-5.5 year delay from initial symptoms. At initial examination, we found that 76% of children were virilized. Ninety-four percent of the tested tumors secreted androgens, which were associated with glucocorticoids in 36%. Adrenal tumors in children were smaller than in adults. Half of them measured less than 10 cm. There were recurrences in 40% of children. The survival rate at 5 years was 49%, 70% if resection was microscopically complete and 7% if not (P < 0.001). CONCLUSIONS: In children, rare adrenal tumors have different diagnostic and prognostic characteristics than in adults; however, recurrences remain frequent. The efficacy of chemotherapy, mainly o,p'-DDD (Mitotane), remains to be evaluated in comparative trials. 相似文献
86.
87.
Telemetering physiological signals from hospital patients by time-sharing infra-red radiation of fixed wavelength means that the limited time available for encoding each data channel imposes constraints on modulation methods. Analogue and digital modulation methods are compared and an unconventional pulse code is proposed. 相似文献
88.
The linear model method of VanRaden and Klaaskate for analyzing herd life was expanded. Information on conception and protein yield was included in the estimation of predicted herd life of Israeli Holsteins. Variance components were estimated by a multitrait animal model. Heritability was slightly higher for herd life than for number of parities, but genetic correlations were close to unity. Animal model heritability estimates of herd life were higher than were sire model estimates. The expected herd life of pregnant cows was 420 d greater than for open cows. Each kilogram of increase in protein yield increased expected herd life by 9.5 d. Heritability of expected herd life increased from 0.11 for cows 6 mo after first calving to 0.14 for cows 3 yr from first calving. The genetic correlation of expected and actual herd life increased from 0.87 for records cut after 6 mo to 0.99 for records cut 3 yr after first calving. Phenotypic correlations increased from 0.61 to 0.94. Sire genetic evaluations based on predicted herd life of live cows were strongly biased if all records were weighted equally, and evaluations derived by weighting incomplete records to account for the effects of current herd life on variance components were nearly unbiased. 相似文献
89.
90.
J Rieger S Durka J Streffer J Dichgans M Weller 《Canadian Metallurgical Quarterly》1999,365(2-3):301-308
Gemcitabine is a novel antimetabolite drug that acts by multiple mechanisms, including inhibition of ribonucleoside diphosphate reductase, of dCMP deaminase and of dCTP incorporation into DNA and RNA. Here, we report that gemcitabine induces cytotoxic and clonogenic death of 12 human malignant glioma cell lines at clinically relevant concentrations around 1 microM. Gemcitabine is thus approximately 100-fold more active than the congener drug, cytarabine. Gemcitabine cytotoxicity of glioma cells does not require wild-type p53 activity: (i) there was no difference in the susceptibility to gemcitabine between cell lines with wild-type p53 and cell lines with mutant or deleted p53; (ii) ectopic expression of a temperature-sensitive p53 protein either at wild-type (32.5 degrees C) or at mutant (38.5 degrees C) conformation had no significant influence on gemcitabine-induced cell death. Gemcitabine cytotoxicity was unaffected by the antioxidants, N-acetylcysteine and phenyl-N-tert-butyl-alpha-phenylnitrone. There was no correlation between the susceptibility to gemcitabine and the endogenous expression of the B cell lymphoma-2 (BCL-2)-family proteins BCL-2, BCL-XL, myeloid cell leukemia-1 (MCL-1), BCL-2-associated X protein (BAX), BCL-2 homologous antagonist/killer (BAK) and BCL-XS. Ectopic expression of BCL-2 moderately attenuated gemcitabine-induced cell death. Similarly, preexposure to the synthetic steroid, dexamethasone, which is commonly used to control cerebral edema in brain tumor patients, reduced gemcitabine cytotoxicity. We conclude that the clinical evaluation of gemcitabine for the adjuvant chemotherapy of malignant glioma is warranted. 相似文献