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51.
Konrad Dabrowski Murat Arslan Jacques Rinchard Maria Esther Palacios 《Journal of the World Aquaculture Society》2008,39(2):174-183
Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11‐ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11‐h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 109 and 15.5 × 109 spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii. 相似文献
52.
Relationship between biochemical constituents of fish semen and fertility: the effect of short-term storage 总被引:5,自引:0,他引:5
Spermatozoa and seminal plasma obtained from rainbow trout and whitefish were analyzed in respect to their aspartate aminotransferase
(AspAT) and alkaline phosphatase activities. In particular, the experiments characterized AspAT optimum pH, optimization of
assay conditions and action of coenzyme, pyridoxal 5-phosphate (vitamin B6). The effect of short-term semen storage at 0°C on biochemical indicators and fertilization rate was examined in both species.
The concentrations of reduced and oxidized ascorbic acid in seminal plasma of both species were several folds higher than
in spermatozoa and blood plasma of fish. Highly significant correlations were found for both species between AspAT activity
(sperm or seminal plasma) and fertilization rate (% of eyed-stage or hatched embryos). For rainbow trout, highly significant
correlations were found between sperm concentration, motility and fertilization rate. These results suggest that several biochemical
indicators of seminal plasma can be used as measures of sperm quality of fish. Some common biochemical parameters for fish
and mammal's semen provide evidence for using fish sperm as a model in biomedical research. 相似文献
53.
Pikeperch (Sander lucioperca L.) is a percid fish species of high commercial value and potential for being aquacultured in Europe. As such, pikeperch needs to be karyologically studied with special attention dedicated to arrangement of the homologous chromosomes into pairs and chromosomal location of the chosen DNA sequences. The karyotype of the pikeperch consists of 48 small chromosomes: One pair of metacentric chromosomes, 15 pairs of submetacentric chromosomes and eight pairs of subtelo‐acrocentric chromosomes (FN = 80). Original data on the chromosomal distribution of early and late replication regions, segments resistant to AluI, DdeI, HinfI and HaeIII restriction endonucleases and identification of the C‐banded heterochromatin presented herein have been used to arrange pikeperch chromosomes into the karyotype. After Primed in situ labeling (PRINS) technique with primers enabling amplification of 5S rDNA sequences, hybridization spots observed on the short (p) arms of two the largest pikeperch submetacentric chromosomes (no. 2). Fluorescence in situ hybridization (FISH) with telomeric PNA (Peptide Nucleic Acid) probe enabled recognition of the conservative telomeric DNA sequences on the pikeperch chromosomes. No interstitial signals were observed. The specimens studied did not show any morphologically differentiated sex chromosomes. 相似文献
54.
Per Foss Trond Storebakken Katharina Schiedt Synnøve Liaaen-Jensen Erland Austreng Konrad Streiff 《Aquaculture (Amsterdam, Netherlands)》1984,41(3):213-226
Visual and chemical determinations revealed that the individual optical isomers of astaxanthin were more efficacious than canthaxanthin in pigmenting the flesh of rainbow trout (Salmo gairdneri, Richardson). The visual assessment of the astaxanthin pigmentation by means of a colour scale correlated well with the chemical determination. The same utilization was found for all three astaxanthin isomers, (3S, 3′S)-, (3R, 3′S)-, (3R, 3′R)-astaxanthin and a 1 : 2 : 1 mixture of the three isomers.No epimerization took place at the chiral centres of C-3 and C-3′ in astaxanthin. Astaxanthin and canthaxanthin were not interconverted. No metabolites were detected in the flesh. 相似文献
55.
Monoterpenoid compounds extracted from wood of Scots pine, Pinus sylvestris L, synergized the attraction of the old-house borer, Hylotrupes bajulus (L), to the male pheromone (3R)-3-hydroxy-2-hexanone ((3R)-ketol) + 1-butanol. Glasshouse experiments using ground traps baited with extracts derived from Scots pine wood or the monoterpenes (+)-alpha-pinene, (-)-verbenone, (-)-trans-pinocarveol and (+)-terpinen-4-ol attracted significantly more H bajulus females, but caught fewer of them, than the synthetic pheromone mixture alone. Traps baited with higher concentrations of the monoterpene mixture attracted fewer females than those baited with lower dosages, whilst very high concentrations of the mixture (6-10 vials) caught no insects. However, a combination of (3R)-ketol + 1-butanol or (+/-)-3-ketol + 1-butanol with monoterpenes resulted in the capture of significantly more females than either the sex pheromone or the monoterpene mixture alone. Traps baited with a blend of the male's sex pheromone or the monoterpenes attracted significantly more, but caught fewer, males than females. Here again, a combination of the above blends enhanced the attraction of males significantly when compared with the attractancy of either of the compounds/mixtures used alone. 相似文献
56.
David M. Spooner Antonio Rivera-Peña Ronald G. van den Berg Konrad Schüler 《American Journal of Potato Research》2000,77(4):261-270
Wild potato (Solanum sect.Petota) germplasm has been collected in Mexico on nine major expeditions, as determined by 20 collections or more from each expedition currently at the United States potato genebank, the National Research Support Program-6 (NRSP-6). These have resulted in 609 accessions with good collection data. In addition, NRSP-6 has germplasm of approximately 90 other Mexican collections that are unspecific regarding date or place of collection. This expedition was funded to collect those remaining collections with no or little germplasm:Solanum clarum,S. xedinense, S. hintonii, S. hjertingii var.physaloides, S. leptosepalum, S. lesteri, S. macropilosum, S. xmichoacanum, S. xsambucinum, andS. stenophyllidium. In addition, some species and species groups (species groups indicated in parentheses) have unresolved taxonomic problems that needed clarification by additional field collections. These are (S. agrimonifolium and S.oxycarpum), (S. brachycarpum, S. guerreroense, S. hougasii, andS. iopetalum - theS. brachycarpum complex), (S. fendleri, S. papita, S. stoloniferum - theS. stoloniferum complex),S. leptosepalum, andS. macropilosum. We conducted a wild potato germplasm collecting expedition in Mexico from August 22 to October 31, 1997. Our 103 collections, 71 as germplasm collections, provide the first germplasm samples forS. hjertingii var.physaloides,S. leptosepalum, andS. macropilosum. They provide additional germplasm of the rare speciesS. clarum, S. xedinense, S. lesteri, S. xmichoacanum, S. xsambucinum, andS. stenophyllidium. We additionally gathered germplasm and field data to help resolve taxonomic difficulties inS. agrimonifolium andS. oxycarpum, theS. brachycarpum complex, and theS. stoloniferum complex. 相似文献
57.
Lenz G Davis RE Ngo VN Lam L George TC Wright GW Dave SS Zhao H Xu W Rosenwald A Ott G Muller-Hermelink HK Gascoyne RD Connors JM Rimsza LM Campo E Jaffe ES Delabie J Smeland EB Fisher RI Chan WC Staudt LM 《Science (New York, N.Y.)》2008,319(5870):1676-1679
Diffuse large B cell lymphoma (DLBCL) is the most common form of non-Hodgkin's lymphoma. In the least curable (ABC) subtype of DLBCL, survival of the malignant cells is dependent on constitutive activation of the nuclear factor-kappaB (NF-kappaB) signaling pathway. In normal B cells, antigen receptor-induced NF-kappaB activation requires CARD11, a cytoplasmic scaffolding protein. To determine whether CARD11 contributes to tumorigenesis, we sequenced the CARD11 gene in human DLBCL tumors. We detected missense mutations in 7 of 73 ABC DLBCL biopsies (9.6%), all within exons encoding the coiled-coil domain. Experimental introduction of CARD11 coiled-coil domain mutants into lymphoma cell lines resulted in constitutive NF-kappaB activation and enhanced NF-kappaB activity upon antigen receptor stimulation. These results demonstrate that CARD11 is a bona fide oncogenein DLBCL, providing a genetic rationale for the development of pharmacological inhibitors of the CARD11 pathway for DLBCL therapy. 相似文献
58.
Anderson RM Latorre-Esteves M Neves AR Lavu S Medvedik O Taylor C Howitz KT Santos H Sinclair DA 《Science (New York, N.Y.)》2003,302(5653):2124-2126
Calorie restriction (CR) slows aging in numerous species. In the yeast Saccharomyces cerevisiae, this effect requires Sir2, a conserved NAD+-dependent deacetylase. We report that CR reduces nuclear NAD+ levels in vivo. Moreover, the activity of Sir2 and its human homologue SIRT1 are not affected by physiological alterations in the NAD+:NADH ratio. These data implicate alternate mechanisms of Sir2 regulation by CR. 相似文献
59.
In continuation of former measurements about gaseous denitrification losses, these losses together with those by nitrate leaching were measured by different methods in a field cropped during two years by wheat. Furthermore, N-uptake by the plants of fertilizer- and soil-N as well as N-im-mobilization in soils during and after the cropping periods was determined by application of highly enriched15N-labeled fertilizer. Denitrification losses determined by the N2O release from C2H2–treated undisturbed soil cores agreed reasonably well with losses obtained by 15N-balance measurements. They both amounted during the cropping periods 12–15 and 6–20 kg N ha?1, respectively. Gaseous N-losses increased mainly during wet periods when the field was barren. Denitrifying enzyme activities and soil respiration (CO2-release) was measured throughout one year. Leaching losses of NO3 from soil-and fertilizer-N occurred only during fall until spring. Leached NO3? originated mostly from mineralized soil-N and very little from previously immobilized fertilizer-N. 相似文献
60.
Audun Korsaeth Philip Müller-Berghfer Konrad Mollenhauer Peter Fischer Martin Bach Hans-Georg Frede 《植物养料与土壤学杂志》1997,160(4):519-523
On the Effect of Organic Surface Cover on Lateral Transport of Isoproturon on Soil Surface The losses of the herbicide isoproturon with the surface runoff and the sediment loss have been measured by means of rainfall simulations on microplots (0.5 × 1 m2) with different mulch materials and increasing soil cover percentages (wheat straw vs. rape leafs). Soil cover by straw showed no significant effect on the runoff discharge, but the total loss of isoproturon increased between 22 and 37%. Soil cover by rape leafs diminished the runoff by between 13 and 61%, the reduction of isoproturon loss was in the same range. It was shown, that the different influences of different mulch materials on runoff and soil loss can lead to different pesticide losses. Therefore, the only giving of “mulch” without specification does not describe such experiments sufficiently. 相似文献