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121.
The social behaviour of Polish Black-and-White dairy cattle (BW) was compared with that of the F1-crossbreds of BW with Jersey (BW × J), Ayrshire (BW × Ay), Holstein-Friesian (BW × HF) and Swedish Black-and-White (BW × SLB). The ethological observations were made under conditions of loose housing.The crossbreds BW × J proved to be most aggressive, excitable and susceptible, as far as milk yield was concerned, to the social tensions connected with moving cows between groups. The BW × Ay were most dominant, least attacked by their group-mates and least susceptible to a group change. The pure-bred BW were calm and subordinate as compared with the crossbreds.The social tensions after a group change caused a mean decrease in milk yield of about 4%. There was a low correlation between the parameters of social behaviour and physical or production traits. The dominance relationships based on spontaneous aggressive interactions differed slightly from those based on interactions motivated by feeding. 相似文献
122.
Summary
Claviceps purpurea strain 129 was cultivated under submerged conditions in a sucrose-citrate medium containing high (36.8 mM) or low (1.84 mM) KH2PO4 concentrations. The permeabilized cells and culture supernatants contained alkaline and acid phosphatases. In the medium containing a high phosphate concentration, the synthesis of extracellular phosphatases was repressed, but that of cellular phosphatases was not. Extracellular phosphatases, especially alkaline phosphatases, were derepressed by transferring the mycelium into a phosphate-free medium. This derepression was inhibited by cycloheximide. In the presence of cycloheximide, the activities of the cellular phosphatases decreased markedly, indicating turnover of these enzymes. The cellular acid phosphatase was inhibited by phosphate (0.025 M–0.1 M) and NaF (0.01 M) while the cellular alkaline phosphatase was only inhibited by phosphate. Both cellular and extracellular alkaline phosphatases were more sensitive to repression by phosphate than the acid phosphatases. The alkaloid synthesizing enzymes were: a) present in mycelia grown in high levels of phosphate and b) activated by decreasing the intracellular phosphate level. 相似文献
123.
This paper presents the results of taxonomic investigation of 8 species of lichens with gyalectoid apothecia collected in North-India and Nepal. Four species are recognized as new:Dimerella isidiata (sp. nova),D. nepalensis (sp. nova),Gyalideopsis lithophila (sp. nova) andRamonia nepalensis (sp. nova). Four species are reported for the first time from Nepal:Coenogonium moniliforme, Gyalectidium caucasicum, Gyalidea lecideopsis andG. scutellaris. 相似文献
124.
The maximum biomass in iron-limited photosynthetic batch cultures of chlorella increased as the logarithm of the iron concentration. The growth yield from iron (Y
x/Fe) showed a marked inverse relation to the specific growth rate. The maximum biomass yield, g dry biomass/g iron consumed, was 7.5x103 with specific growth rate 0.108 h-1; the minimum was 0.79×103 with specific growth rate 0.145 h-1. The maximum specific growth rate in the exponential phase of Fe limited cultures varied as the initial Fe concentration. Fe-limited growth made the cells adhere to a glass surface.Abbreviation O.D.
optical density 相似文献
125.
Summary The presence of 1% agar in the fixation and substrate solutions for the histochemical demonstration of thiamine pyrophosphatase (4.4 mM TPP; 3.6 mM Pb2+; 0.025 Tris-maleate buffer, pH 7.2) clearly facilitates the localization of the enzyme in Golgi apparatus in cold microtome sections prepared from unfixed specimens. 相似文献
126.
Antonín Vězda 《Folia Geobotanica》1978,13(1):99-102
Eine nèue foliikole Flechte (Pleurotrema epiphylla sp. n.) aus Zaïre (Zentral-Afrika) wird beschrieben. Die systematischen Beziehungen der neuen Art zu den anderenPleurotrema-Arten und die Stellung der GattungPleurotrema innerhalb der FamilieParatheliaceae wird kurz diskutiert. 相似文献
127.
The production of ε-pyrromycinone glycosides inStreptomyces galilaeus increased 12-fold, with respect to the wild strain, as a result of a sequential procedure including both natural selection
and treatment with mutagens (nitrous acid, UV light and γ-irradiation). Nitrous acid exhibited the highest mutagenic effect,
both in increasing the productivity and in inducing blocked mutants. A mutant strain blocked in the biosynthesis of glycosides
and accumulating free ε-pyrromycinone as the principal metabolite was obtained. 相似文献
128.
Anthracyclines 总被引:2,自引:2,他引:0
129.
130.
Storage proteins of the seeds (cotyledons) of the South-American speciesPhaseolus caracalla were compared by means of immunoelectrophoretic methods with other representatives of the genusPhaseolus. These proteins most resemble the proteins of the co-called tropical group (i.e. Ph. atropurpureus, Ph. geophilus, Ph. bracteatus, Ph. semierectus) and least the so-called American endemites (Ph. vulgaris, Ph. coccineus, Ph. acutifolius, Ph. lunatus), the main globulin of which is of a completely different specificity. The proteins ofPh. caracalla are less similar to the group of the so-called Asiatic species (Ph. aureus, Ph. calcaratus, Ph. angularis, Ph. aconitifolius, Ph. trilobus) including the analyzed representatives ofVigna sinensis; their main globulin is only partly similar to that ofPh. caracalla. Some considerations on the relationship ofPh. caracalla with the so-called tropical species is presented. 相似文献