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141.
The rational design of closed aquaculture systems requires data on metabolite production rates. The metabolite of primary concern is often ammonia. Ammonia formation rates for a number of tropical ornamental fish types and sizes were determined. Cyprinus carpio, Barbus conchonius, Pseudotropheus auratus and Carassius auratus auratus were used as representative egg-layers while Xiphophorus variatus and Xiphophorus helleri represented the live-bearers. Specific metabolite production rates, R′, were determined not only in terms of mass of fish but also the amount of feed. For instance, R′ (Amm-N) for 1.33 g unit size Barbus conchonius was determined to be 155.9 mg Amm-N kg-fish−1% feed−1 day−1. In an attempt to produce a general model for all the ornamental fish investigated, all values of R′ obtained were correlated with fish sizes to produce an equation R′ (Amm-N) = 1.57-[30×log(itUW)] where UW = unit fish size.  相似文献   
142.
A growth hormone minigene carrying its natural promoter (237 nucleotides of chromosomal DNA) was stably propagated in a murine retrovirus containing hypoxanthine-guanine phosphoribosyltransferase as a selectable marker. Glucocorticoid and thyroid hormone inducibility was transferred with the growth hormone gene. Recombinant virus with titers of 10(6) per milliliter was recovered. This demonstration that retroviruses can be used to transfer a nonselectable gene under its own regulatory control enlarges the scope of retroviral vectors as potent tools for gene transfer.  相似文献   
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Twenty-seven cultivars of mulberry fruits ( Morus atropurpurea Roxb) were analyzed for their total phenolic content, total anthocyanin content, and peroxyl radical scavenging capacities. The proanthocyanidin contents of the fruit were also quantified using 4-dimethylamino-cinnamaldehyde assay, and characterization was attempted using electrospray ionization mass spectra. The phenolic compounds of mulberry fruits were characterized using HPLC with ESI-MS and diode array detection. Results showed that the content of mulberry fruits varied with different cultivars with total phenolic content, total anthocyanin content, total proanthocyanidin content, and peroxyl radical scavenging capacities ranging from 0.060-0.244, 0.001-0.056, 0.001-0.015, and 0.301-1.728, respectively. Good correlations were observed among the phenolic, anthocyanin, and proanthocyanidin contents and the radical scavenging capacities of mulberry fruits. Mulberry fruits were found to contain low amount of proanthocyanidins. The high total phenolic content of mulberry fruits were mainly contributed by anthocyanins, rutin, and chlorogenic acids. The lipid soluble antioxidants are profiled by an HPLC method developed in-house, and the results of selected mulberry fruits revealed significant amounts of lutein and delta- and gamma-tocopherols but low alpha-tocopherol. Our results provide useful antioxidant nutritional information of a mulberry cultivar that has potential for large scale plantations.  相似文献   
146.
Embryonic mortality is found to be the main source of reproductive wastage in domestic ruminants. Many genes are involved in the growth and development of the embryo, and the interferon‐stimulated gene 15 (ISG 15) is one of the major gene stimulated by interferon tau, the maternal recognition of pregnancy signal in ruminants. In this study, both genomic and cDNA sequences of ISG 15 from Bos indicus (Deoni breed) were amplified and characterized. The genomic sequence of Deoni ISG 15 exhibited 99% identity with Bos taurus and 97% identity with that of Bos mutus and Bubalus bubalis. Moreover qRT‐PCR analysis revealed constitutive expression of the ISG 15 mRNA in peripheral blood mononuclear cells of Deoni heifers and multiparous cows during early pregnancy. Fourteen Deoni heifers and fifteen multiparous Deoni cows were synchronized for timed AI by CIDR‐Ovsynch protocol, and six animals were kept as cyclic control in each group. Blood samples were collected on days 7, 14, 16, 18, 21, 30 and 45 from the day of AI. Pregnancy was confirmed by plasma progesterone level through ELISA. A significantly higher expression of ISG 15 mRNA was found on day 16 (< .05) and day 18 (< .05) of pregnancy in nulliparous heifers. Although in multiparous Deoni cows ISG 15 expression was greater in pregnant cows, difference was statistically non‐significant. The result of this study indicates that ISG 15 gene expression is upregulated during 16–18 days of pregnancy and could be used as an early pregnancy marker in dairy cows especially in heifers.  相似文献   
147.
Flour proteins of hard and soft winter wheats grown in Oregon were characterized by size‐exclusion HPLC (SE‐HPLC). Flour pasting characteristics were assessed by a Rapid Visco Analyser (RVA). Principle component scores (PCS) were calculated from both RVA data and from absorbance area and % absorbance values from SE‐HPLC. The PCS and cross‐products, ratios, and squares were used to derive wheat classification and quality prediction models. A classification model calculated from PCS of SE‐HPLC data could reliably separate these hard and soft wheats. The prediction models for mixing and noodle characteristics showed better performance when calculated from PCS values of both SEHPLC and RVA data than from SE‐HPLC data only. The R2 values of prediction models for mixograph absorption, peak time, and tolerance were 0.827, 0.813, and 0.851, respectively. Prediction models for noodle hardness, cohesiveness, chewiness, and resilience immediately after cooking had R2 values of 0.928, 0.928, 0.896, and 0.855, respectively. These results suggest that multivariate methods could be used to develop reliable prediction models for dough mixing and noodle characteristics using just SE‐HPLC and RVA data.  相似文献   
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