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401.
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The course of the mycelium low productivity during the first phase of the usual two-stage process of penicillin biosynthesis was studied. It was found that the low productivity of the mycelium at the beginning of the fermentation process was probably associated with catabolic regression of the penicillin-producing system. The high specific growth rate registered in the experiments (0.06-0.08 hours-1) had no negative effect on the mycelium productivity. It was not possible to connect the productivity level with the mycelium age, because young and mature mycelium had the same producitivity levels at any developmental stage under the same conditions.  相似文献   
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The paper is devoted to an analysis of combined x-ray findings supplemented by CT findings in patients with sarcoidosis detected for the first time with early signs of this disease. A conclusion has been made that apart from lymph node enlargement, sarcoidosis is characterized by lung parenchymal changes which manifest themselves as symptoms of broncho-alveolitis. Characteristic x-ray symptom complexes are described. Roentgeno-semiotics of these changes were compared with the results of morphological investigation of transbronchial puncture specimens. Roentgenologically detectable changes showed good correlation with morphology findings. The authors have also emphasized the importance of morphological verification of this disease at early stages.  相似文献   
406.
Age peculiarities in composition of the upper tracheobronchial lymph nodes have been studied in 60 corpses at the age of 16-70 years. Cause of death has not been connected with diseases of blood, lymphatic system or thoracic origins. Routine histological and morphometric methods have been applied. Certain age-dependent rearrangement in the connective tissue stroma, trabecular vegetations and differences in correlations of structural components have been noted. A rather essential volumetric increase of the medullary substance takes place at the level of hilus of the lymph node. Cellular composition of the lymph nodes is greatly polymorphous but is more or less constant for each age group. The number of macrophages containing carbon pigment is increasing with age.  相似文献   
407.
The aim of this research was to select plant species that could be effective in the phytoremediation of a former oil-sludge pit. Seven crop plants (Triticum aestivum L., Secale cereale L., Avena sativa L., Hordeum vulgare, Sorghum bicolor L. Moench, Panicum miliaceum L., and Zea mays L.), five wild grasses (Lolium perenne L., Bromopsis inermis, Agropyron cristatum L., Agropyrum tenerum L., and Festuca pratensis Huds.), and three legumes (Medicago sativa L., Trifolium pratense L., and Onobrychis antasiatica Khin.) were screened for phytotoxicity, including the assessment of germination, shoot biomass, and root biomass, in a pot experiment. The estimation of oil-sludge degradation in the root zone of the tested plants showed that rye accelerated cleanup most effectively, degrading all of the main contaminant fractions in the oil sludge by a total of 52%. Although alfalfa had a lower phytoremediation potential than did rye, it maintained large numbers of soil microorganisms, including polycyclic aromatic hydrocarbon degraders, in its rhizosphere. Rye and alfalfa were chosen for a large-scale study to remediate an oil-sludge pit on the grounds of a petroleum refinery. Remediation monitoring confirmed the effectiveness of rye: the oil-sludge content decreased consistently for 3 years and remained low in comparison with the results from other plant species.  相似文献   
408.
Short-time disturbances of the microcirculation in rabbits had a different influence on the ATP-ase activity of smooth and rough microsomes of the liver and heart. Mg+2ATP-ase activity in the liver decreased in both microsome fractions; as in the heart, the enzyme activity increased only in the smooth (light) microsomes.  相似文献   
409.
It was shown that total DNA of the blue-green algae A. variabilis can be isolated as a compact particle with the sedimentation constant of 2700--2900S by lysis of the cells with the TritonX-100--sodium deoxycholate mixture in 1.0 M NaCl. The structure isolated is sensitive to ribonuclease and the hydrodynamic shift. It was found that within a compact chromosome A. variabilis DNA is circular and negatively superhelicized. The density of superturns of the DNA in 0,2 M NaCl at 20 degrees C is 0,061, which corresponds to one negative turn per 165 pairs of DNA bases.  相似文献   
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