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231.
Polymorphism of 11 microsatellite DNA loci was analysed in Polish Red (PR), Hereford and Holstein-Friesian (HF) cattle raised in Poland and genetic distance among these breeds was determined. At the 11 loci (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA23, ETH3, ETH225 and BM1824) analysed with automated DNA sizing technology, a total of 213 alleles were identified: 76 in PR, 76 in HF, and 61 in Hereford. All the microsatellite DNA markers showed high polymorphism. Polymorphism information content (PIC) calculated for each marker exceeded 0.5, except for the ETH3 locus in Hereford cattle (PIC=0.475), and heterozygosity (H) ranged from 54.1% to as much as 85.2%. The coefficient of genetic distance was 0.354 between PR and Hereford, 0.414 between HF and Hereford, and 0.416 between PR and HF cattle. 相似文献
232.
Age-related variations in chemical composition of egg matter were found in females in some studies, but they do not seem to
be a universal phenomenon. In contrast, egg size can be well predicted from female age. The relationship has a parabolic shape,
but the predicted size decrease of eggs from old females has not always been documented. Female size is an important contributor
to egg size, both at intra- and inter-specific levels. Dependence of fecundity on body size has usually been described by
a power function. A trade-off between egg number and size is considered in light of life history strategies. During a spawning
season egg size may differ between successive batches, but lack of effects of egg batch sequence was reported in some studies.
In yolk-feeding fish three discrete periods of elevated mortality are typically observed: shortly after egg activation, during
hatching, and at final yolk resorption. The positive relationships between female size, egg size and offspring size/resistance
to starvation and predation are a key pathway in parent–egg–progeny relationships. Both maternal and paternal effects contribute
to the total survival of offspring, but they operate in different ways and at different times. In contrast to the importance
of female size, no paternal size effects were revealed, but density and motility of spermatozoans were decisive. Typically,
paternal effects diminish earlier in ontogeny. Major factors governing embryonic survival (fertilisation success and hatching
success) differ from factors to which starvation mortality of yolk-feeding larvae is related. Embryonic survival is affected
by female age via egg matter composition, by egg ripeness and paternal factors such as sperm density and motility. In contrast, starvation
mortality of yolk-feeding larvae depends largely on female attributes (age, size and fecundity) via egg size, and, in some batch spawners, on egg batch sequence. Among teleost species egg size varies across a wide range (from
0.3 to 85–90 mm in diameter). Species that spawn large eggs are relatively rare. Caloric value of egg dry matter varies within
a narrow range of 20–30 J mg−1. Ecosystem and evolutionary components, and reproductive style are factors that contribute to egg endowment and yolk quality.
During the last decade considerable progress was made in the methodology and understanding of paternal effect on progeny performance
in fishes. This paper reviews these of parent–egg–progeny relationships. 相似文献
233.
Alagille D Baldwin RM Roth BL Wroblewski JT Grajkowska E Tamagnan GD 《Bioorganic & medicinal chemistry letters》2005,15(4):945-949
We described the synthesis and biological evaluation of MPEP analogs functionalized at the position 3 of the phenyl ring. The results point out the limitation in the choice of a functional group at this position; the only substituents leading to retention of activity are NO(2) (IC(50)=13 nM) and CN (IC(50)=8 nM). 相似文献
234.
Hennig EE Godlewski MM Butruk E Ostrowski J 《FEMS immunology and medical microbiology》2005,44(2):143-150
Helicobacter pylori vacuolating cytotoxin VacA causes multiple effects on epithelial cell function and morphology, but the effects of VacA on signal transduction pathways and the cytoskeleton have not been investigated in detail. In this study, we analyzed the effects of native VacA on HeLa and AGS cell adhesion to fibronectin and laminin under serum-free conditions. Confocal microscopic examination revealed increased number of cells with rounded morphology and inhibition of actin fiber formation, in the presence of VacA. VacA binds to fibronectin in vitro in a dose-dependent manner. This interaction was partly inhibited by a peptide containing an arginine-glycine-aspartic acid motif. The adhesion of HeLa cells to fibronectin, but not to laminin, was decreased in the presence of VacA. Thus, VacA may interact with fibronectin and influence integrin receptor-induced cell signaling and cytoskeleton-dependent cell functions. 相似文献
235.
Skała E Wysokińska H 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(7-8):583-586
Production of tanshinones (tanshinone I and IIA) was determined in roots of Salvia przewalskii micropropagated plants. It was found that the total tanshinone content (tashinone I and tashinone IIA) was dependent on the age of the analyzed plants. The roots of 2-year-old in vitro regenerated plants at flowering stage produced highest tanshinone levels (3.8 mg/g dry weight of tanshinone I and 7.6 mg/g dry weight of tanshinone IIA). 相似文献
236.
Ewa?Chwe?atiuk Tadeusz?W?ostowskiEmail author Alicja?Krasowska Elzbieta?Bonda 《Biometals》2005,18(3):283-291
Recent study has shown that a short photoperiod increases the accumulation and toxicity of cadmium (Cd) in the bank vole as compared to a long photoperiod. Since many of the effects of photoperiod on physiological processes in small mammals are transduced by the pineal gland and its hormone melatonin, in this study the effect of subchronic melatonin injection (7 mol/kg/day for 6 weeks) on the hepatic, renal and intestinal Cd accumulation in the bank voles raised under a long photoperiod and exposed to dietary Cd (0.9 mol/g) was examined. Simultaneously, histological examinations of the liver and kidneys, and analyses of metallothionein (MT) and lipid peroxidation were carried out. Melatonin co-treatment brought about a significant increase in the hepatic (61%), renal (79%) and intestinal (77%) Cd concentrations as compared to those in the Cd alone group. However, the concentrations of MT in the liver and kidneys of the Cd + melatonin co-treated bank voles did not differ from those in the Cd alone group. Also, histopathological changes in the liver (infiltration of leukocytes) and kidneys (glomerular swelling and a focal tubular cell degeneration) as well as an increase (2-fold) in the renal lipid peroxidation occurred only in animals from the Cd + melatonin group. These data indicate that (1) subchronic melatonin injection has similar effect on the tissue accumulation and toxicity of Cd to that produced by a short photoperiod and (2) the Cd-induced toxicity in the liver and kidneys of melatonin co-treated bank voles is probably due to increased Cd accumulation and decreased synthesis of MT. 相似文献
237.
Paluchowska MH Bugno R Bojarski AJ Charakchieva-Minol S Duszyńska B Tatarczyńska E Kłodzińska A Stachowicz K Chojnacka-Wójcik E 《Bioorganic & medicinal chemistry》2005,13(4):1195-1200
Novel, flexible arylpiperazine gepirone analogs (1a-3a) with a mixed 5-HT1A/5-HT2A receptor profile, low D2 receptor affinity, and agonistic (2a) or partial agonistic (1a, 3a) activity toward 5-HT1A receptor sites were synthesized. Their conformationally restricted counterparts (1b-3b) were selective 5-HT1A ligands (over 5-HT2A and D2 receptors), which turned out to be agonists (2b, 3b), or partial agonist (1b) of 5-HT1A receptors. 相似文献
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