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31.
The presence of bacteria in salted anchovies during and at the end of the curing process was investigated. Attempts to isolate bacteria under aerobic or anaerobic conditions led to the isolation of only bacteria of the genus Pediococcus which were identified as Pediococcus halophilus. The isolates correspond to a rather heterogeneous group in which some of the members differ in some biochemical tests from the types described in the literature.  相似文献   
32.
Early developmental stages of theAnemonia germ are characterized by asynchronously dividing nuclei and an extreme delay of blastomere differentiation. The nuclei migrate to the periphery, whereas nutritive substances remain in the interior. Following this stage, the appearance of cell boundaries results in the formation of the blastoderm and the simultaneous division of the yolk into many fragments. Most of them are exclusively filled with reserve material; only very few contain zooxanthellae or nuclei. On the embryo's surface, conically shaped bundles of long microvilli are obvious. They appear to be less regularly arranged than the spines of oocytes before insemination. Pigment granules that have originated from fusing Golgi vesicles are crowded peripherally in the blastoderm cells. In the nucleoplasm single annulate lamellae that seem to be cut off from the nuclear envelope can frequently be found. There is no further cellular differentiation until gastrulation is completed. Though yolk-containing cellular fragments occupy nearly the whole blastocoel, entoderm formation occurs by invagination. Ultrastructural observations provide evidence of the existence of interstices between entoderm cells that allow all nutritive substances to pass gradually into the gastric cavity. In the region of the blastoporus there are cellular processes enveloping reserve material. Presumably, these observations indicate a so-called filtration of nutritive yolk (Korschelt & Heider, 1909) that might represent an additional mode for the transfer of yolk-containing cellular fragments from blastocoel into gastrocoel.  相似文献   
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In contrast to what has been postulated, penicillin G at its optimal lytic concentration of 0.1 g per ml did not lead to a detectable activation of autolytic wall processes in staphylococci in terms of the release of uniformly labelled wall fragments from cells pretreated with the drug for 1 h. Rather a considerable inhibition of this release was observed. A similarly profound inhibition of the release of peptidoglycan fragments occurred when staphylococci pretreated for 1 h with 0.1 g penicillin per ml acted as a source of crude autolysins on peptidoglycan isolated from labelled normal cells of the same strain. This clearly demonstrated that the overall inhibition of autolytic wall processes caused by penicillin was mainly due to a decreased total autolysin action rather than to an altered wall structure. Furthermore, no substantial penicillin-induced inhibition of the incorporation of 14C-N-acetylglucosamine into the staphylococcal wall could be observed before bacteriolysis started, i. e., approximately during the first 80 min of penicillin action. These results are not consistent with any of the models hitherto proposed for the action of penicillin.Dedicated to Prof. Dr. Gerhart Drews on the occasion of his 60th birthday  相似文献   
35.
The results obtained by topographical studies on the immunoreactive peptide systems in the embryonic and adult avian brain (domestic fowl, domestic mallard, pigeon, Japanese quail, and zebra finch) can be realized only by means of phylogenetical comparisons. The comparative studies mainly demonstrate a fascinating constancy of the immunological properties and the spatial distribution of the neuropeptides. Independent of the development of the neopallium, and the increasing cerebral complexity, the spatial distribution of the neuropeptides, the location of their main perikaryal accumulations which are interconnected by immunoreactive fiber projections (and thereby forming widespread but continuous peptide systems) remain nearly unchanged during vertebrate evolution. The recognition of the neuropeptides as integral parts of the central nervous system is demonstrated by the fact that neuropeptidergic structures connect sensory inputs with central nervous areas as well as with the peripheral endocrinium.  相似文献   
36.
"Viili," a fermented milk product, has a firm but viscous consistency. It is produced with traditional mesophilic mixed-strain starters, which have various stabilities in dairy practice. Thirteen morphologically different types of phages were found in 90 viili samples studied by electron microscopy. Ten of the phage types had isometric heads with long, noncontractile tails, two had elongated heads with long, noncontractile tails, and one had a unique, very long elongated head with a short tail. Further morphological differences were found in the tail size and in the presence or absence of a collar, a baseplate, and a tail fiber. To find hosts for the industrially significant phages, we examined the sensitivities of 500 bacterial isolates from starters of the viili. Seven of the phages attacked Streptococcus cremoris strains, three attacked S. lactis subsp. diacetylactis strains, and four attacked Leuconostoc cremoris strains. Some phages differed only in their host specificity. Hosts were not found for 4 of the 13 morphological types of phages.  相似文献   
37.
This note reports the interaction of three currently used tricyclic antidepressant drugs (clomipramine, imipramine and amitriptyline) with delta, mu and kappa opioid binding sites in the bovine adrenal medulla. Clomipramine was the only drug interacting with delta and mu sites. On the contrary, all three drugs showed a significant interactions with subtypes of the kappa binding site. Clomipramine was the most active on the kappa 2 and kappa 3 subtypes while amitriptyline showed the highest interaction with the kappa 1 subtype. On the contrary the tricyclic cyproheptadine did not present any interaction with opioid binding sites in our system. This interaction between tricyclic antidepressants and opioid binding sites might be the origin of their analgesic action.  相似文献   
38.
The seasonal variation in water chemistry was followed during 1980 and 1981 in four mountain brooks in the southern part of Swedish Lapland. In the area investigated the soil is calcareous and the brook water is very well buffered during the major part of the year, with alkalinity varying between 0.4 and 1.0 milliequivalents per liter and with pH values about 7.5. These years the snow had a pH of approximately 5.2, which was considerably higher than has been reported from adjacent areas in the lower, coniferous region. During snowmelt the water discharge increased drastically, and although the net transport of bicarbonate increased, alkalinity showed low values due to dilution with meltwater. pH decreased, but not further than to 6.3–6.5, far from values reported in 1979 (pH less than 5), apparently due to the comparatively clean snow. A slight deficit in alkalinity, as compared to the nonmarine calcium and magnesium content, points to an acidification impact on the area. During maximum runoff some chemical variables, like aluminium, iron, nitrogen and phosphorus, behaved reversely to what might be expected during dilution and reached maxima in concentrations. It is concluded that the extreme runoff characteristics of high mountain areas make brook water more sensitive to acid precipitation than might be expected when regarding only the calcareous properties of soil and bedrock.  相似文献   
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Zusammenfassung Inaktive Riesenchromosomen der Speicheldrüsen ausgewachsener Chironomus thummi-Larven zeigten nach 60 min Inkubation mit 0,05 N Putrescin-, Spermidin-oder Spermin-Lösung erneute Syntheseaktivitäten, die sich im Einbau von radioaktiv markiertem Uridin autoradiographisch zu erkennen geben. Diese Beobachtung wird im Zusammenhang mit der bekannten genaktivierenden Wirkung von Mg++ diskutiert. Auf der Basis zahlreicher biochemisch analoger Wirkungen von Polyaminen und Mg++ wird ein ursprünglich für die genaktivierende Wirkung von Mg++ postuliertes Modell auf Polyamine übertragen.
Stimulation of gene activities by polyamines an autoradiographic study with giant chromosomes of Chironomus thummi
Summary Inactive salivary gland giant chromosomes of full grown Chironomus thummi larvae showed after 60 min of incubation in 0.05 N putrescine, spermidine or spermine solutions autoradiographically demonstrable incorporation of radioactiv labelled uridine caused by a reactivation of RNA synthesis. This observations is discussed in relation to the known gene activating effect of Mg++, and, since polyamines and Mg++ have numerous effects in common, it is suggested that polyamines affect gene activity in a way similar to Mg++.
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