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371.
The objective of the study was to describe the effects of a short acting glucocorticoid which was administered immediately after parturition in dairy cows on haematological, immunologic and metabolic parameters. The study was performed on 104 cows, 52 cows received an intramuscular injection of 2 mg/100 kg BW dexamethasone within 12 hours after parturition. The numbers and the phagocytic activity of granulocytes and monocytes were measured on day 1 and day 3 post partum in 17 randomly chosen cows from each group. From day 1 to day 3 the percentage of phagocytic granulocytes increased in the dexamethasone group from 73.2 +/- 6.1% to 79.6 +/- 6.6% (P < 0.05); in the control group the percentage remained unchanged (74.7 +/- 6.3% and 76.2 +/- 5.8%). The cellular phagocytic activity of granulocytes did not change significantly between day 1 and 3. In both groups the phagocytic activity of monocytes also remained unchanged. The concentrations of endotoxin, haptoglobin and the anti-lipid-A-IgG-antibody-titer did not show significant differences between the groups. Between both groups differences were not observed in the clinical parameters, milk yield or in the incidence of diseases in the peripartal period. The effects of the glucocorticoid on the metabolic parameters were especially seen in bilirubin and free fatty acid concentration. The present study shows that a single injection of glucocorticoids within 12 hours after parturition did not influence the phagocytic activity of neutrophils and monocytes negatively and did not have an effect on the measured parameters of acute-phase-response. Therefore, it seems possible to benefit from the positive effects of glucocorticoids on metabolism in this critical early postpartal period in high yielding cows.  相似文献   
372.
Infections of avian polyomavirus (APV) are known to cause fatal disease in a wide range of psittacine and non-psittacine birds. Here, we present a survey to investigate the existence of subpopulation of persistent or subclinically infected parrots inside the population of captive psittacine birds in Germany. DNA was isolated from feathers of 85 symptom-free birds from 20 different genera (all psittaciformes) taken from 30 different breeders from all over Germany. The presence of APV was analysed by performing polymerase chain reaction assays (PCR). APV was detected in none of the samples, indicating that the existence of a subpopulation of captive psittacine birds having a persistent APV infection in Germany seems to be relatively low.  相似文献   
373.
Brachycome muelleri Sonder (Corunna daisy) is an endangered annual herb, endemic to the upper Eyre Peninsula of South Australia. It is restricted to a single population occupying an area of approximately 3 ha on steep, south-facing cliff-foot slopes of the Baxter Hills. Its unique habitat, within an otherwise generally arid region, optimises soil moisture retention through the provision of concentrated water catchment, shade, and low evaporation rates during the growing season. Weeds had the potential to significantly disrupt recruitment, growth and reproductive output, but grazing did not constitute a direct threat to the population. Fresh seeds were innately dormant, requiring a period of after-ripening before they would germinate. Dormancy was artificially broken by gibberellic acid (GA3) treatment. Germination was optimal at 20 °C, and it was proposed that temperature plays an important role in regulating germination in situ. B. muelleri seeds did not respond to smoked water treatment, and GA3 (1000 mg l−1) was recommended as a routine seed treatment to stimulate germination. Trial translocations using seed as founder propagules resulted in low establishment, growth and flowering rates. Established seedlings provided several advantages over seed as founder propagules, including higher success rates, more vigorous growth, and improved seed yields in the first season. Successful regeneration, proliferation and expansion of a new translocated population was observed and recorded over four consecutive years. We suggest that conservation management of this species should include the establishment of several new populations by translocation to suitable, isolated, weed-free sites.  相似文献   
374.
An evaluation of production orders for medicated feedingstuffs for pigs given in 1998 in Schleswig-Holstein showed aminoglycosides, colistin and beta-lactam antibiotics as regularly used antibiotical ingredients. The presented study analyses the production orders which include these antibiotics more in detail particularly with regard to the prescribed dosages. In part, there were deviations to the rules of good clinical practise for the use of anitbiotics. The applied dosage of spectinomycin and apramycin was often lower than suggested in the literature. The low oral bioavailability of amoxicillin was not considered when using amoxicillin in medicated feedingstuffs.  相似文献   
375.
Silaffins are uniquely modified peptides that have been implicated in the biogenesis of diatom biosilica. A method that avoids the harsh anhydrous hydrogen fluoride treatment commonly used to dissolve biosilica allows the extraction of silaffins in their native state. The native silaffins carry further posttranslational modifications in addition to their polyamine moieties. Each serine residue was phosphorylated, and this high level of phosphorylation is essential for biological activity. The zwitterionic structure of native silaffins enables the formation of supramolecular assemblies. Time-resolved analysis of silica morphogenesis in vitro detected a plastic silaffin-silica phase, which may represent a building material for diatom biosilica.  相似文献   
376.
The purpose of this study was to examine if substantial bone loss occurs in weaned pigs by feeding a phosphorus-deficient diet with or without fumaric acid. Eighteen weaned pigs were used. The animals were assigned to three groups: group C (control; 0.65% P on DM basis), group LP (low phosphorus; 0.37% P on DM basis) and group LPF (low phosphorus plus fumaric acid; 0.35% P on DM basis plus 2% fumaric acid). These three diets were fed to the groups for a period of four weeks after a two-week adaptation period. Blood samples were collected once a week. Carboxyterminal telopeptide of type I collagen (ICTP) in serum was used as a bone resorption marker. Osteocalcin (OC) and bone-specific alkaline phosphatase (bAP) were used as bone formation markers. Bone mineral density (BMD) and content (BMC) were determined by peripheral quantitative computer tomography. BAP activities significantly increased (24%) in group LPF, and at the last sampling day group LPF had significantly increased activities in comparison to group C. In contrast, ICTP concentrations significantly increased with time in group LP and LPF, and at the last sampling day group LPF had significantly increased activities in comparison to group C. BMD and BMC in femur and tibia significantly decreased in group LP and LPF. The results show that P-deficient diets induce a bone loss. Fumaric acid did not influence the degree of bone loss. With a better understanding of its effect on bone, dietary phosphorus requirements in pigs could be more precisely defined.  相似文献   
377.
378.
Clarithromycin was administered to eight dogs intravenously and orally. A suspension or a tablet was given to animals both immediately after feeding and on an empty stomach. Neither the formulation nor the time of administration in relation to feeding significantly influenced the pharmacokinetic parameters. The lowest mean (±SD) maximum plasma concentration (Cmax) of 3.0 ±0.6 μg/ml, the lowest bioavailability (F) of approximately 69 per cent and the shortest time above the proposed breakpoint of susceptibility (L) of 2.9 ±1.3 hours were observed with the suspension after feeding. The highest Cmax of 3.6 ±0.8 (Jig/ml, the highest F of 83 per cent and the longest L of 4.5 ±2.0 hours were observed with the suspension in the fasted group. The mean time at which Cmax occurred (tmax) was between one and two hours after administration. In conclusion, clarithromycin is potentially suitable for therapeutic use in dogs, pending species-specific studies of safety and therapeutic efficacy.  相似文献   
379.
An in vitro digestion method was developed which simulates the conditions in the digestive tract of a fish as closely as possible. Physiological temperature optimum, pH value, water content of digesta in the stomach and gut, proteolytic activity and passage time through the stomach and gut are taken into consideration. The incubation of protein-containing raw materials with the digestive fluids of the fish in a titrator, the subsequent separation of soluble digestion products using an HPLC molecular sieve, and the quantitative amino acid analysis of the break-down products constitute three steps of increasing resolution and complexity of experimental procedure.In order to describe the potential of this physiologically oriented in vitro method, the digestion of Pruteen, a single-cell protein (SCP) of a methanophilic bacterium, is presented under the simulated conditions of the gut of rainbow trout (Salmo gairdneri).  相似文献   
380.
Zusammenfassung Aus Blättern der KartoffelpflanzeSolanum tuberosum Aquila wurde außer Cycloartenol (I), 24-Methylen-cycloartanol (II) (?), Lophenol (III), 24-Methylen-(IV) und 24-Äthyliden-lophenol (V) in 0,05%iger Ausbeute (bezogen auf Blatt-Trockengew.) ein Steringemisch isoliert, das nach dem Molekül-Massenspektrum (Ionisierung durch Anlagerung energiearmer negativer Ladungsträger) aus etwa 49% -Sitosterin (VIII), 36% Stigmasterin (IX), 12% Cholesterin (VI) und 3% Campesterin (VII) zusammengesetzt ist. Weiterhin ließen sich die homologen n-Paraffine C25H52 bis C33H68 und iso-Paraffine C29H60 bis C33H68 (Hauptkomponente mit ca. 51% n-Hentriacontan) sowie geringe Mengen höherer aliphatischer Ketone, vor allem Tritriacontanon, gaschromatographisch bzw. molekülmassenspektrographisch nachweisen.
Summary In addition to cycloartenol (I), 24-methylene-cycloartanol (II) (?), lophenol (III), 24-methylene-(IV) and 24-ethylidene-lophenol (V) a mixture of sterols has been isolated from leaves of the potato plantSolanum tuberosum Aquila (0,05% of the dry weight), which, according to our molecular mass spectrographic investigations employing negative ionization, contains approximately 49% -sitosterol (VIII), 36% stigmasterol (IX), 12% cholesterol (VI), and 3% campesterol (VII). Furthermore the homologous n-alkanes C25H52 to C33H68 and iso-alkanes C29H60 to C33H68 (the main component being n-triacontane with ca. 51%) as well as some higher aliphatic ketones, especially tritriacontanone, have been detected by gas-liquid chromatographic and molecular mass spectrographic methods.

am ¶rt;au Solanum tuberosum L., , (I), 24- (II) (?), (III), 24-- (IV) 24-- (V) ( 0,05% ). « -» ( ) 49%- (VIII), 36% (IX), 12% (VI) 3% (VII). () « -» - ( 2552 3368) - ( 2960 3368), 51%-, , .


VII. Mitteilung: von Ardenne und Mitarb. (1965b).

Zugleich IV. Mitteilung der Reihe Molekül-Massenspektrographie von Naturstoffen. — III. Mitteilung: von Ardenne und Mitarb. (1965b).

Forschungsinstitut Manfred von Ardenne, Dresden-Weißer Hirsch.

Teil der Dissertation von G. Osske, Univ. Halle, 1963.  相似文献   
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