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971.
972.
973.
Alterations were recorded from capillaries and connective tissue by means of optical light and electron microscopy in investigations of subepithelial structures, following experimental Escherichia coli infection. These alterations led to an impairment of the blood-udder barrier and thus to increased extravasation of cells (especially neutrophilic granulocytes). They were found to accumulate in subepithelial connective tissue and, eventually, to penetrate in high quantity the epithelium proper, and, consequently, to be considerably involved in alterations to the latter. 相似文献
974.
Delayed hypersensitivity reactions to antigens injected intradermally are reported as not occurring in the cat. Cats infected with viable Mycobacterium bovis (BCG) organisms developed a transient migration-inhibition response of their leukocytes to tuberculin. The migration-inhibition response subsided in 6 weeks in spite of the persistance of viable BCG. Significant intradermal reactions to tuberculin 60 days after BCG injection did not occur. The response of the cat differs from that of many mammalian species in which strong in vivo and in vitro delayed hypersensitivity type reactions persist with mycobacterial infections. Despite the lack of continued measurable delayed hypersensitivity, the cat appears to have adequate resistance to mycobacterial infections. 相似文献
975.
G Michel 《Archiv fuer experimentelle veterinaermedizin》1979,33(5):745-751
The activities of succinate dehydrogenase (SDR) and lactate dehydrogenase (LDH) as well as the ribonucleic acid levels in the epithelium of both the lactic ducts and alveoli of lactic glands were examined in heifers, close to full term, lactating cows, some of them with subclinical mastitis lesions, and udder biopsies of two cows. The activities of SDH and LDH as well as RNA levels were pronounced in the glandular epithelium of alveoli and in the epithelium of the lesser lactic ducts. All three parameters were also pronounced but at lower levels in the cells of the apical stratum of the two-layer epithelium in the greater lactic ducts. Relationships were found to exist between the enzyme activities and RNA levels and the lactation cycle. Their patterns and manifestations were more or less typical of those areas of the lactic gland which were affected by mastitis. 相似文献
976.
977.
978.
Fidel Payan-Zelaya Jean Michel Harmand Antonio Flores-Macías John Beer Guadalupe Ramos-Espinoza Fernando de León González 《Agroforestry Systems》2013,87(2):439-450
To investigate the effects of microbial inocula and Erythrina poeppigiana pruning residues on soil K, NO3?, and NH4+ concentrations, a greenhouse trial, a field experiment in an organic farm, and three in vitro tests were conducted. Under controlled conditions, weak, temporary effects (10 %) on maize seedling growth were observed on poor soils (taken from the 10–20 cm layer) in the first 2 weeks after application. Positive effects of pruning residue applications on soil K levels (0.09 cmol kg?1, on average) were detected in both the field and greenhouse study. However, significant effects due to the addition of microbial inocula on soil K concentrations were not detected in the field; thus, microbial applications were ineffective at enhancing nutrient availability under field conditions. In contrast, in the in vitro experiments, CO2 production was 31 % greater than that of untreated soil on the 8th and 15th days of incubation. These results highlight the importance of adding tree pruning residues to support coffee-plant nutrition. Experimental outcome data could be valuable for further studies focused on microbial application dosage and timing. 相似文献
979.
Courtin F Huerre M Fyfe J Dumas P Boschiroli ML 《Journal of Feline Medicine and Surgery》2007,9(3):238-241
A 2-year-old, 4 kg, healthy, domestic shorthair female cat presented with ulcerated subcutaneous nodules on the commissures of its mouth. The cat was negative for feline leukaemia virus and feline immunodeficiency virus. Skin mycobacteriosis was diagnosed after detection of numerous acid-fast bacilli in Ziehl Neelsen-stained smears from the ulcers. Feline leprosy was suspected following preliminary polymerase chain reaction results: positive for Mycobacterium genus but negative for Mycobacterium tuberculosis and Mycobacterium avium complexes. Mycobacterium lepraemurium was later identified following DNA sequence analysis of the 5' end of the 16S rRNA gene and the 16S-23S internal transcribed spacer region. Microscopic lesions consisted of pyogranulomas containing mainly large foamy macrophages with 10-100 intra-cellular acid-fast bacilli per field. The cat was cured after surgery and a 14-week course of clofazimine (30 mg daily) and clarithromycin (50 mg twice daily). 相似文献
980.
Since 1995, more than 150 extrasolar planets have been discovered, most of them in orbits quite different from those of the giant planets in our own solar system. The number of discovered extrasolar planets demonstrates that planetary systems are common but also that they may possess a large variety of properties. As the number of detections grows, statistical studies of the properties of exoplanets and their host stars can be conducted to unravel some of the key physical and chemical processes leading to the formation of planetary systems. 相似文献