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931.
Summary In comparison with intact yeast, dehydrated-rehydrated cells of Saccharomyces cerevisiae show significantly higher ethanol production from exogenous substrate under both anaerobic and aerobic conditions, particularly when low concentration (0.1%) of glucose are used. For populations with a higher percentage of viable rehydrated cells (above 70%) a more notable decrease in the Pasteur effect (the difference between the quantity of ethanol formed under anaerobic and aerobic conditions) is observed.  相似文献   
932.
Testes, collected from 11 species of demersal and platform associated pelagic fishes, were examined microscopically for petroleum induced lesions. The fish were taken from 19 oil and gas production platforms and four control sites from the north-central Gulf of Mexico, during two periods, spring and late summer. The status of the spermatogenic cycle at the time specimens were collected correlated well with the known spawning times for the respective species of fish with one exception. Histopathological evaluation revealed acidophilic granular cells, chromatophores, degeneration and focal leucocytic aggregations as the most prominent and abundant conditions in testes, with encapsulated cysts, protozoa and helminths being observed only rarely. No evidence of adverse effects on gonadal morphology was found.  相似文献   
933.
We screened a total of 460 stool samples from humans with and without underlying disease for the black yeast and neurotrope, Exophiala dermatitidis using conventional and molecular identification procedures. Sixteen (3.5%) samples were positive. Twelve out of the sixteen positive samples where the fungus was recovered were from individuals who had diarrhoea at the moment of isolation. Two asymptomatic positive cases were within the age bracket of 21–30. Susceptibility testing of the strains using the CLSI M38 protocol suggests that almost all the strains were susceptible to amphotericin B, 5 fluorocytosine, itraconazole, fluconazole and voriconazole. Considering the health risk currently posed by this organism in Asia, especially among healthy younger subjects of the population and the scarcity of data on this fungus in Africa in general and Nigeria in particular, some recommendations were suggested.  相似文献   
934.
935.
Tree size, survival, and coppicing of micropropagated plantlets, macropropagated cuttings, and seedlings of Eucalyptus grandis Hill ex Maiden were monitored through 57 months in a study in southern Florida to assess propagation options. Two plantlet lines developed by direct micropropagation and orchard open-pollinated seedlings from three ortets were compared in the main study. Rooted cuttings from up to four ramets of each of the three ortets and another ortet were examined in an adjacent supplemental study. Freezes at six and 16 months killed most initial and first-coppice stems to the ground. Most developmental differences in the main study were consistent from ages 2 to 57 months. Propagation by ortet interactions were observed beginning at 21 months, due to the poor performance of seedlings of one ortet after the second freeze. At 57 months, no differences in tree height, DBH, volume, or survival were detected between plantlet lines and between rooted cuttings and plantlets, but seedlings were inferior to plantlets and cuttings. Vegetative propagules had more uniform tree size at every age, with typically less than one-half the variability observed among seedlings. Even though plantlets and cuttings may be more expensive to produce, they have numerous advantages over seedlings for E. grandis plantation establishment in Florida.  相似文献   
936.
The acarological+ study of dust samples from the homes of allergic patients and normal persons in Moscow mite antigens were detected, respectively, in 66.7% and 38.1% of homes. The indirect mast cell degranulation test and the brain gliacyte volume change test in white rats gave similar results. The occurrence of Dermatophagoides pteronyssinus was approximately twice as great of D. farinae, and the numerical prevalence of the former species over the latter one was 1.3-fold. Dermatophagoides mites occurred in the homes of allergic patients 1.8-2.3 times as frequently as in the homes of normal persons.  相似文献   
937.
Ischemia of the rat small intestine lasting 40 min leads to pronounced structural disorders in lipid transport across the enterocytes, reduction in enzymatic activity of the cells and in absorption function, and to the loss of fat with feces. The normalization of the indicated parameters occurs at varying times and ends after 1 month. Fat transport abnormality is marked by an increase in lipid drops in the cavities of the smooth endoplasmic network, appearance of large and numerous matrix lipids, by a greater reduction, as compared to normal, in the membranes of the rough endoplasmic network and lamellar complex in the epithelium of the villi. Accumulation of lipids and retardation of their release from the cytoplasm are determined by incomplete differentiation of the epithelium, which is also combined with a decreased enzymatic activity.  相似文献   
938.
The production of virus-neutralizing antibodies in high titers has been found to occur in persons immunized with tissue-culture rabies vaccines, concentrated and non concentrated, intramuscularly in a dose of 1 ml in accordance with reduced immunization schedules.  相似文献   
939.
Human and animal blood smear staining with PAPh has revealed mononuclear leukocyte-erythrocyte aggregates. Administration of retinoic acid increased concentration and dimensions of these aggregates and was followed by preferential accumulation of PAPh-negative osmotically unstable erythrocytes. Similar changes were detected in the blood samples of women engaged in the production of retinoic acid. Aggregate concentration showed positive correlation with erythrocyte sedimentation rate and no correlation with prothrombin time.  相似文献   
940.
Experiments on E. coli used as a model have revealed that fatty-acid composition is one of the characteristics which determine the viability of bacteria in the air. The viability of microbial cells in the air has been shown to increase with the increase of the pool of cyclopropane acids and the palmitic acid/palmitoleic acid ratio in the cells, irrespective of their genotype and the phase of their growth.  相似文献   
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