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1.
Zusammenfassung An Hand von Photogrammen wird der Bau regenerierter Schuppen beim Goldfisch, der Karausche und beim Karpfen nach Versuchen in Aquarien und Versuchsteichen besprochen.Die jüngsten Regenerate (3 Wochen) haben hauptsÄchlich wabenartigen Bau und nur wenige Zuwachslinien. Die RadiÄrfurchen sind vermehrt und sind nur soweit ausgebildet, als Ringlinien verlaufen.Mit zunehmendem Alter des Regenerates vermehren sich die Ringlinien. Es bleibt aber immer in der Schuppenmitte beim Regenerat ein vergrö\ertes Wachstumszentrum von wabenoder netzartigem Bau (Karausche, Goldfisch) oder von körneligem, amorphem Bau (Karpfen).Auch nach vielen Jahren sind an dem vergrö\erten Wachstumszentrum noch regenerierte Schuppen von normalen zu unterscheiden. Auch lÄ\t sich durch Vergleich mit normalen Schuppen noch nachtrÄglich bestimmen, wann das Regenerat gebildet wurde.Nicht nur bei vollkommenem Verlust, sondern auch bei Verletzung und BeschÄdigung einer alten, noch im Fischkörper verbleibenden Schuppe wird darunter ein Regenerat gebildet.Regenerierte Schuppen fanden sich auf dem Körper eines Flu\fisches (Brachse Abramis brama) in II%, bei zwei zweisömmrigen Spiegelkarpfen in 31 und 27% vor.Regenerierte Schuppen sind hauptsÄchlich am Schwanzende, an den Seiten und im vorderen Körperviertel zu finden. Dies sind die Stellen, an denen der Fischkörper am leichtesten scheuert und beschÄdigt wird.Herrn Professor Dr. Karl v. Frisch zum 60. Geburtstag gewidmet.  相似文献   

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Roach, rudd, bream and their natural hybrids of 2 cm standard length or larger can be definitively identified by their enzyme electrophoretic patterns. Zymograms of lactate dehydrogenase and esterases as produced by vertical starch gel electrophoretic analysis of whole fry or adult eye extracts are the most useful in this respect. The lactate dehydrogenase isozymes, containing B sub-units, migrate more anodally in rudd and bream than in roach. Due to the tetrameric structure of lactate dehydrogenase, in hybrid rudd x roach and roach x bream, eleven isozymes can be observed as compared with six in the parental patterns. Esterases show unique patterns for all species and hybrids. With the exception of one fraction in rudd x bream, the esterase patterns of hybrids show summations of the parental phenotypes.  相似文献   

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River buffalo, sheep, and goat spermatozoa were cross-hybridized using double color fluorescence in situ hybridization (FISH) with bovine Xcen- and Y-chromosome painting probes, prepared by DOP-PCR of laser-microdissected-catapulted chromosomes, to investigate the possibility of using bovine probes for sexing sperm of other members of the family Bovidae. Before sperm analysis, the probes were hybridized on metaphase chromosomes of each species, as control. Frozen-thawed spermatozoa of cattle, river buffalo, sheep, and goat were decondensed in suspension with 5 mM DTT. Sperm samples obtained from three individuals of each species were investigated, more than 1,000 spermatozoa were scored in each animal. FISH analysis of more than 12,000 sperm revealed high level of sperm with X- or Y-signals in all of the species investigated, indicating FISH efficiency over 99%. Significant interspecific differences were detected in the frequency of aberrant spermatozoa (aneuploid and diploid) between goat (0.393%) and sheep (0.033%) (P < 0.01), goat and cattle (0.096%) (P < 0.5), as well as between river buffalo (0.224%) and sheep (P < 0.5). There was no significant difference between river buffalo and cattle. The present study demonstrated that it is possible to use bovine X-Y painting probes for sexing and analyzing sperm of other species of the family, thus facilitating future studies on the incidence of chromosome abnormalities in sperm as well as on sex predetermination of embryos for the livestock industry. Mol. Reprod. Dev. 67: 108-115, 2004.  相似文献   

4.
The genes encoding thermostable cellulases E2 and E3 of Thermomonospora fusca were expressed in plants under the control of the constitutive, hybrid Mac promoter. For both E2 and E3, the genes were modified so as to remove the sequence encoding the bacterial leader peptide. Western blot analysis indicated that expression levels of recombinant cellulase in tobacco lines ranged up to about 0.1% (E2) and 0.02% of soluble protein (E3). No phenotypic effect of cellulase expression was noted. Recombinant E2 expressed in either tobacco or alfalfa was active and retained heat stability. These findings are an important first step in the development of crop plants as a production system for cellulases.  相似文献   

5.
The total flavonoid content of leaf extracts (70% ethanol) from fig (Ficus carica L.), carob (Ceratonia siliqua L.) and pistachio (Pistacia lentiscus L.) plants were determined by using reverse phase high-performance liquid chromatography (HPLC)-and analyzed by UV/VIS array and electrospray ionization (ESI)-mass spectrometry (MS) detectors. As a base for comparison, flavonoid type and level were also determined in extracts from soybeans and grape seeds. It was found that the major flavonoids in Ficus are quercetin and luteolin, with a total of 631 and 681 mg/kg extract, respectively. In Ceratonia leaves, nine different flavonoids were detected. The major one was myricetin (1486 mg/kg extract), with a similar level in Pistacia (1331 mg/kg extract, myricetin). The present study is the first to report the presence of the isoflavone genistein in the Pistacia leaf, which was discovered to consist of about a third of the genistein level detected in soybean.  相似文献   

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Ohne ZusammenfassungMit 14 TextabbildungenHerrn Prof. Dr.Theodor Herzog zum 80. Geburtstag in Verehrung gewidmet.  相似文献   

9.
Willows were rapidly propagated by repeated division of cultured rooted shoots into a larger number of nodal segments. Rapid clonal propagation of mountain-ash and black locust was achieved by induction of shoots from axillary buds and a multiple shoot culture was used for rapid multiplication. Excised shoots were rooted in an agar medium with a low concentration of auxin and rooted plantlets were transplanted to soil.  相似文献   

10.
Dr. M. Girbardt 《Planta》1962,58(1):1-21
Ohne ZusammenfassungMit 118 Textabbildungen  相似文献   

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We have investigated Ca2+ activity during pollen germinationand the possibility that it may be responding to a phosphoinositidesignal transduction pathway, by employing inhibitors of Ca2+channels (verapamil and TMB-8), EGTA as a Ca2+ scavenger andthe inositol 1-phosphatase inhibitor lithium chloride. We havefound that at least two Ca2+ pools are utilized during pollengermination. Influx of extracellular Ca2+ appears to be necessaryfor the germination of apple and tobacco pollen, but it doesnot appear to be required for the germination of potato pollen.Conversely, activation of intracellularly stored Ca2+ was necessaryfor optimal germination of all three pollen species. LiCI hadstrong effects on pollen germination. At 5 mM LiCI, pollen germinationwas inhibited by 78% for apple, 84% for tobacco, and 74% forpotato. Li+ inhibition was overcome by the addition of Ca2+,which restores germination of all three species to 85–100%of that observed in controls, myo-lnositol also partially overcomesLi+ inhibition of pollen germination, thus providing some evidencefor a link between Li+ inhibition and Ca2+ rescue, myo-lnositolrescue of Li+ inhibition was most effective for potato pollen.Chlorotetracycline (CTC) spectroscopy revealed a higher levelof membrane-Ca2+ in Li + -treated pollen grains than in controls,and the short pollen tubes which did emerge did not accumulatemembrane-associated Ca2+. The results suggest that Li+ inhibitionmay interfere with the release (activation) or partitioningof membrane-Ca2+ during pollen germination and that this Ca2+activity may be responding, at least in part, with a phosphoinositidesignal transduction pathway. Key words: Pollen germination, lithium inhibition, calcium, inositol, calcium inhibitors  相似文献   

14.
European Journal of Wildlife Research - Durch Vergleich von 145 Wolfsschädeln mit 165 Schädeln großer Hunde fand der Verfasser sieben Merkmale am Schädel und ein Merkmal am...  相似文献   

15.
A rhizobox experiment was conducted to examine the P acquisition characteristics of cotton (Gossypium hirsutum L.), wheat (Triticum aestivum L.) and white lupin (Lupinus albus L.) under P-deficient conditions. We aimed to identify whether cotton is physiologically efficient at acquiring P through release of protons, phosphatases or carboxylates. Plants were pre-grown in the upper compartment of rhizoboxes filled with a sand and soil mixture to create a dense root mat against a 53 μm polyester mesh. For each species, two P treatments (0 and 20 mg P kg?1) were applied to the upper compartment in order to create P-deficient and P-sufficient plants. At harvest, the upper compartment with intact plants was used for collection of root exudates while the lower soil compartment was sliced into thin layers (1 mm) parallel to the rhizoplane. Noticeable carboxylates release was only detected for white lupin. All P-deficient plants showed a capacity to acidify their rhizosphere soil to a distance of 3 mm. The activity of acid phosphatase was significantly enhanced in the soil-root interfaces of P-stressed cotton and wheat. Under P-deficient conditions, the P depletion zone of cotton from the lower soil compartment was narrowest (<2 mm) among the species. Phosphorus fractionation of the rhizosphere soil showed that P utilized by cotton mainly come from NaHCO3–Pi and NaOH–Po pools while wheat and white lupin markedly depleted NaHCO3–Pi and HCl–P pools, and the depletion zone extended to 3 mm. Wheat also depleted NaOH–Po to a significant level irrespective of P supply. The study suggests that acquisition of soil P is enhanced through P mobilization by root exudates for white lupin, and possibly proton release and extensive roots for wheat under P deficiency. In contrast, the P acquisition of cotton was associated with increased activity of phosphatases in rhizosphere soil.  相似文献   

16.
A study was conducted to compare astaxanthin binding ability of solubilized muscle proteins of Atlantic salmon (Salmo salar L.), haddock (Melanogrammus aeglefinus L.) and Atlantic halibut (Hippoglossus hippoglossus L.). Muscle proteins of juvenile Atlantic salmon, haddock and halibut were solubilized by sequential extraction of muscle tissue using low ionic strength solutions. Electrophoretic protein profiles of the six solubilized fractions from these species were similar. Each solubilized fraction from the three species was examined for its relative astaxanthin binding capacity. The amount of bound astaxanthin was significantly different (P < 0.05) among the six fractions of each species. Significant differences in astaxanthin binding were only found for fractions A and E among the species. The amount of bound astaxanthin in various fractions of each species showed a good correlation (R2 = 0.80–0.92) with the ANS (8-anilino-1-naphthalenesulfonate) fluorescence intensity of those fractions. The pattern and extent of astaxanthin binding to the muscle proteins of juvenile salmon, haddock and halibut is comparable to that reported previously for adult Atlantic salmon [Saha, M.R., Ross, N.W., Gill, T.A., Olsen, R.E., Lall, S.P., 2005. Development of a method to assess binding of astaxanthin to Atlantic salmon S. salar L. muscle proteins. Aquacult. Res. 36, 336–343.]. These combined observations suggest that the carotenoid binding capacity of the muscle proteins of salmon is not the limiting factor in the deposition of carotenoid in their flesh.  相似文献   

17.
Plant material is a rich source of valuable compounds such as flavanones. Their different forms influence bioavailability and biological activity, causing problems with the selection of plant material for specific purposes. The purpose of this research was to determine selected flavanone (eriodictyol, naringenin, liquiritigenin, and hesperetin) enantiomer contents in free form and bonded to glycosides by an RP‐UHPLC‐ESI‐MS/MS method. Different parts (stems, leaves, and flowers) of goldenrod (Solidago virgaurea L.), lucerne (Medicago sativa L.), and phacelia (Phacelia tanacetifolia Benth.) were used. The highest content of eriodictyol was found in goldenrod flowers (13.1 μg/g), where it occurred mainly as the (S)‐enantiomer, and the greatest proportion of the total amount was bonded to glycosides. The richest source of naringenin was found to be lucerne leaves (4.7 μg/g), where it was mainly bonded to glycosides and with the (S)‐enantiomer as the dominant form. Liquiritigenin was determined only in lucerne, where the flowers contained the highest amount (1.2 μg/g), with the (R)‐enantiomer as dominant aglycone form and the (S)‐enantiomer as the dominant glycosylated form. The highest hesperetin content was determined in phacelia leaves (0.38 μg/g), where it was present in the form of a glycoside and only as the (S)‐enantiomer. A comparison of the different analyte forms occurring in different plant parts was performed for the first time.  相似文献   

18.
Abstract The vascular patterns of the ventral side of the kidneys in Bufo bufo and Rana ridibunda is similar. Strong venulae renales revehentes dominate. In Bombina variegata and Xenopus laevis, however, also many superficially located glomeruli are found at the ventral side. In Xenopus further branching of the renal arteries into afferent arterioles attracts attention. Bundles of delicate afferent arterioles originate within circumscribed areas of the renal artery. The glomerular layer of the kidney is tightest in Bombina, and has its maximal extension in Rana. It covers up to 2/3 of the thickness of the kidney while in the other species studied the glomeruli are restricted to the ventral third of the kidney. Glomeruli with double afferent or efferent arterioles were rarely found in Xenopus. The vascularization of the dorsal side of the kidneys is characterized by the presence of large (Bufo, Rana, Xenopus) or small (Bombina) venulae renales advehentes.  相似文献   

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Vulnerability of three fish groups (tilapia, common carp, mullet) to predation by Nile perch Lates niloticus was evaluated. The study was conducted in aquaria and in cages placed in concrete ponds. Common carp Cyprinus curpio was the more vulnerable to predation by Nile perch followed in order by mullet ( Mugil cephulus and M. cupito ) and Nile tilapia Oreochromis niloricus . Medium-size Nile perch (30–32 cm t.l. ) were able to consume tilapia up to 14 cm t.l. , while tilapia of 15 cm total length were not eaten. Ratios of 1 : 10 to 1 : 15 between Nile perch and ready-to-spawn females of O. niloticus were found to be adequate to control tilapia reproduction.  相似文献   

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