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251.
The ability of seed germination to increase the nutritional quality of chickpea was studied. Chickpea flours germinated for 0, 24 and 48 h were evaluated nutritionally by determination of protein efficiency ratio (PER), net protein ratio (NPR), digestibility and essential amino acid availability in vivo. A significant increase in ascorbic acid was observed during germination. PER and NPR values indicated that germinated chickpea flours compared favorably to casein. Protein digestibility decreased as germination time increased. Essential amino acid availability did not change after 24 h of germination, but a small decrease was observed after 48 h. The increase in some amino acids during germination may account for the observed increase in PER for the germinated flours. Seed germination enhanced significantly the nutritional quality of chickpea protein and substantially increased the ascorbic acid level.Contribution No. 4359, Arizona Agricultural Experiment Station, University of Arizona, Tucson, AZ 85721, USA.  相似文献   
252.
Silibinin has recently received attention as a potential cancer chemopreventive agent because of its antiproliferative and anticarcinogenic effects. A simple and specific reversed-phase high-performance liquid chromatography method was developed and validated for the quantitation of silibinin in human plasma. Sample preparation involved simple protein precipitation, and separation was achieved on a Waters Atlantis C18 column with flow rate of 1.0 mL/min at 40 degrees C and UV detection at 290 nm. Silibinin was detected as two peaks corresponding to trans-diastereoisomers. The peak area was linear over the investigated concentration range (0-5000 ng/mL). The limits of detection were 2 and 1 ng/mL for the two diastereoisomers (d1 and d2), with a recovery of 53-58%. This method was utilized to detect silibinin in plasma of colorectal patients after 7 days of treatment with silipide (silibinin formulated with phosphatidyl choline).  相似文献   
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Most studies on feed efficiency in beef cattle have focused on performance in young animals despite the contribution of the cow herd to overall profitability of beef production systems. The objective of this study was to quantify, using a large data set, the genetic covariances between feed efficiency in growing animals measured in a performance-test station, and beef cow performance including fertility, survival, calving traits, BW, maternal weaning weight, cow price, and cull cow carcass characteristics in commercial herds. Feed efficiency data were available on 2,605 purebred bulls from 1 test station. Records on cow performance were available on up to 94,936 crossbred beef cows. Genetic covariances were estimated using animal and animal-dam linear mixed models. Results showed that selection for feed efficiency, defined as feed conversion ratio (FCR) or residual BW gain (RG), improved maternal weaning weight as evidenced by the respective genetic correlations of -0.61 and 0.57. Despite residual feed intake (RFI) being phenotypically independent of BW, a negative genetic correlation existed between RFI and cow BW (-0.23; although the SE of 0.31 was large). None of the feed efficiency traits were correlated with fertility, calving difficulty, or perinatal mortality. However, genetic correlations estimated between age at first calving and FCR (-0.55 ± 0.14), Kleiber ratio (0.33 ± 0.15), RFI (-0.29 ± 0.14), residual BW gain (0.36 ± 0.15), and relative growth rate (0.37 ± 0.15) all suggest that selection for improved efficiency may delay the age at first calving, and we speculate, using information from other studies, that this may be due to a delay in the onset of puberty. Results from this study, based on the estimated genetic correlations, suggest that selection for improved feed efficiency will have no deleterious effect on cow performance traits with the exception of delaying the age at first calving.  相似文献   
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Beef outputs from dairy farms make an important contribution to overall profitability in Irish dairy herds and are the sole source of revenue in many beef herds. The aim of this study was to estimate genetic parameters for animal BW and price across different stages of maturity. Data originated from 2 main sources: price and BW from livestock auctions and BW from on-farm weighings between 2000 and 2008. The data were divided into 4 distinct maturity categories: calves (n = 24,513), weanlings (n = 27,877), postweanlings (n = 23,279), and cows (n = 4,894). A univariate animal model used to estimate variance components was progressively built up to include a maternal genetic effect and a permanent environmental maternal effect. Bivariate analyses were used to estimate genetic covariances between BW and price per animal within and across maturity category. Direct heritability estimates for price per animal were 0.34 ± 0.03, 0.31 ± 0.05, 0.19 ± 0.04, and 0.10 ± 0.04 for calves, weanling, postweanlings, and cows, respectively. Direct heritability estimates for BW were 0.26 ± 0.03 for weanlings, 0.25 ± 0.04 for postweanlings, and 0.24 ± 0.06 for cows; no BW data were available on calves. Significant maternal genetic and maternal permanent environmental effects were observed for weanling BW only. The genetic correlation between price per animal and BW within each maturity group varied from 0.55 ± 0.06 (postweanling price and BW) to 0.91 ± 0.04 (cow price and BW). The availability of routinely collected data, along with the existence of ample genetic variation for animal BW and price per animal, facilitates their inclusion in Irish dairy and beef breeding objectives to better reflect the profitability of both enterprises.  相似文献   
258.
Practical components for three-dimensional molecular nanofabrication must be simple to produce, stereopure, rigid, and adaptable. We report a family of DNA tetrahedra, less than 10 nanometers on a side, that can self-assemble in seconds with near-quantitative yield of one diastereomer. They can be connected by programmable DNA linkers. Their triangulated architecture confers structural stability; by compressing a DNA tetrahedron with an atomic force microscope, we have measured the axial compressibility of DNA and observed the buckling of the double helix under high loads.  相似文献   
259.
Sunflower contains two classes of seed proteins: the 11S globulins (helianthinins) and the 2S albumins. Polymorphisms have been detected within both classes and therefore they have been proposed as genetic markers. The objectives of the present study were to identify sunflower seed protein polymorphisms and locate them on an RFLP linkage map. Seed proteins of 68 inbred lines and four Argentinian open-pollinated populations were studied by SDS-PAGE. The helianthinins were separated into ten bands arranged in fourgroups of Mr of 22.5, 25.5, 32 and 38 kDa and all lines showed identical banding patterns. The albumins were separated into eight to tenbands in the Mr range 10 and 18 kDa. The lines showed either a band of Mr of 14.5 or of 15.5 kDa. HAR1, HAR2, ZENB8 and ZENB12 had the 15.5 kDa, whereas the remaining lines had the 14.5 kDa. The 14.5 and 15.5 kDa polypeptides were also segregating in the Impira INTA population. One hundred and fifty F2:3 families derived from ZENB8 × HA89 were used as the mapping population. The electrophoretic patterns of the families were either those of the two parental lines or presented both the 14.5 and 15.5 kDa polypeptides. No family showed absence of both bands, suggesting that they are allelic variants. The 2S albumin locus was located in the interval between the markers ZVG0051 and ZVG0052, at approximately 9 cM from ZVG0051 and at 6 cM from ZVG0052, on linkage group 11 of the public sunflower RFLP map. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
260.

Background

Inflammatory bowel disease (IBD) and intestinal small cell lymphoma (ISCL) are common diseases in cats. The prevalence of alterations in the serum concentrations of fat soluble vitamins, such as vitamin D, in cats with IBD and ISCL is unknown.

Hypothesis/Objectives

The objective of this study was to measure serum 25 hydroxyvitamin D (25[OH]D) concentrations in cats with IBD or ISCL. Serum 25(OH)D also was measured in healthy cats, and in hospitalized ill cats with nongastrointestinal diseases.

Animals

Eighty‐four cats were included in the study: 23 in the healthy group, 41 in the hospitalized ill group, and 20 in the IBD/ISCL group.

Methods

Retrospective study. Serum samples for vitamin D analysis were frozen at −20°C until serum 25(OH)D was measured by high‐performance liquid chromatography (HPLC).

Results

Although there was overlap in serum 25(OH)D concentrations among the 3 groups, serum 25(OH)D concentrations were significantly lower in the cats with IBD or ISCL compared to healthy cats (P < .0001) and hospitalized ill cats (P = .014). In the IBD/ISCL group, there was a significant moderate positive correlation between serum albumin and 25(OH)D concentrations (r = 0.58, P = .018).

Conclusion and Clinical Importance

The median serum concentration of 25(OH)D was significantly lower in cats with IBD/ISCL than in healthy cats and in hospitalized ill cats. Additional studies are required to elucidate the mechanism of hypovitaminosis D in cats with gastrointestinal diseases, to define the best management strategy to treat this complication, and to investigate its potential prognostic implications.  相似文献   
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