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241.
Histopathology of experimental Aspergillus fumigatus keratitis 总被引:2,自引:0,他引:2
Histopathological studies in rabbit's eyes, 7 and 14 days after intracorneal inoculation with 1×105
Aspergillus fumigatus conidia have been performed.Similar lesions were found in both periods with fungal hyphae in the anterior third of corneal stroma, round cell infiltration from the sclero-corneal edge and in the anterior chamber and, neovascularization.No lesions were found in the Descemet's membrane.Gomori silver-methenamine stain with hematoxiline-eosine counter-stain was found to be the most reliable stain to detect fungal presence in corneal stroma, and Masson's trichromic stain in the study of pathological changes in ocular elements. 相似文献
242.
Purification and characterization of two trypsin-like enzymes from the digestive tract of anchovy Engraulis encrasicholus 总被引:3,自引:0,他引:3
A Martínez R L Olsen J L Serra 《Comparative biochemistry and physiology. B, Comparative biochemistry》1988,91(4):677-684
1. Two trypsin-like enzymes, designated Trypsin A and B, were purified from the pyloric caeca and intestine of anchovy by (NH4)2SO4 fractionation, affinity chromatography (Benzamidine-Sepharose-6B) and ion exchange chromatography (DEAE-Sepharose). 2. Both trypsins catalyzed the hydrolysis of N-benzoyl-DL-arginine p-nitroanilide (BAPNA), p-tosyl-L-arginine methyl ester (TAME), casein and myofibrillar protein and they were inhibited by several well established trypsin-inhibitors. 3. The enzymes had mol. wts of 27,000 (Trypsin A) and 28,000 (Trypsin B). Their isoelectric points were about 4.9 (Trypsin A) and 4.6 (Trypsin B) and they had similar amino acid composition. 4. The enzymes had a pH optimum of 8-9 for the hydrolysis of BAPNA and of 9.5 for the digestion of casein and myofibrillar protein. Their activity and stability were affected by calcium ions. 5. Trypsins A and B resemble other fish trypsins in their mol. wt, pI, kinetic properties and the instability at low pH and they are similar to bovine trypsin in their dependence of Ca2+ for activity and stability. 相似文献
243.
244.
Dr. Concepción Calvo Ana García de la Paz Victoria Bejar Emilia Quesada Alberto Ramos-Cormenzana 《Current microbiology》1988,17(1):49-53
Thirty-eight strains ofDeleya halophila species were examined for production of phage after mitomycin C induction. Thirty-two of them were able to inhibit growth of some other strains. Phage F9-11, isolated fromD. halophila strain F9-11, showed an isometric head and a noncontractile tail. The effects of salt concentrations variation on the stability and replication of this phage were established. Its replication was possible at a wide range of marine salt concentrations, from 2.5% to 15% (wt/vol). Stability seems to be influenced by osmolarity of medium rather than by NaCl level. The euryhaline character showed by F9-11 phage is evoked as an important factor for the survival of this phage in its environment. 相似文献
245.
Hepatic coma was induced in rats chronically treated with CCl4, by means of a single injection of ammonium acetate. The activities of glutamate decarboxylase (GAD) and GABA transaminase (GABA-T), as well as the synaptosomal uptake and release of [3H]GABA, were measured in the following brain areas of the comatose rats: cortex, striatum, hypothalamus, hippocampus, midbrain and cerebellum. Hepatic coma was associated with a general decrease of GAD activity, whereas GABA-T activity was diminished only in the hypothalamus, striatum and midbrain. During hepatic coma, the K+-stimulated [3H]GABA release was notably diminished in the striatum and cerebellum, whereas a significant increase was observed in the hippocampus. [3H]GABA uptake increased in most regions after CCl4 treatment, independently of the presence of coma. The results indicate that GABAergic transmission seems to be decreased in most cerebral regions during hepatic coma. 相似文献
246.
247.
A marked decrease in overall learning capacity has been observed in rats injected with cyanate. Therefore it was of interest to test whether learning influenced carbamylation of brain proteins. Incorporation of [14C]cyanate into proteins of the mamillary body was selectively modified following operant conditioning of the rat, so that trained rats showed an asymmetric image with higher levels of incorporation in the right side than in the left side, as compared to control rats. These results were confirmed using fluorescein isothiocyanate. The asymmetry persisted once the learning had been well established. 相似文献
248.
Synopsis Evidence is presented which suggests that the nonparasitic lamprey, Lampetra (Eudontomyzon) gracilis Kux, 1965, is conspecific with the parasitic lamprey Eudontomyzon danfordi Regan, 1911. The diagnostic characters of the holotype and of the non-type material of E. gracilis are features found in E. danfordi specimens in their second and final year of adult life, thereby making the former a junior synonym of the latter. 相似文献
249.
250.
Summary Immobilization of Escherichia alcalescens cells into genu-carrageenan gel for L-aspartic acid production was studied with respect to the optimized preparation of heterogenous biocatalyst /2.5–3.0% genu-carrageenan, 15% biomass, 50–55 °C, tannin added/. 相似文献