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Microorganisms from two Escherichia coli serotypes were allowed to interact with cultured epithelial cells and the interaction process was followed from 30 to 360 min. Destruction of the microvilli on the epithelial monolayers as well as of the cells themselves was observed only with 0111:H2 serotype. 相似文献
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Maturation of the CNS in neonatal animals is dependent upon both sensory input and the constant availability of metabolic fuel. Previous reports indicate that the preferred metabolic substrate for the developing rat brain is lactate. In this study, we used the neonatal Sprague-Dawley rat to investigate a possible interactive role between touch and the regulation of serum lactate. Two hundred and fifty rats (postnatal d 0-7) were exposed to a standard tactile stimulation (TS) regimen to mimic nonspecific maternal stimulation. This regimen consisted of stroking the dorsum with a soft camel hair brush for 30 s every minute for 10 min. Serum lactate and glucose levels were measured after TS. In newborn (d 0) rats, lactate levels were increased by 207% in stroked pups versus controls. This elevation of serum lactate persisted for 30 min after cessation of TS. On d 7, TS increased lactate only 11%. Glucose levels were unaffected at all ages. In neonatal pups, pretreatment with pentobarbital blocked the effect of TS, whereas epidermal growth factor evoked a synergistic response. Capsaicin pretreatment had no effect. Mixed arteriovenous blood gases revealed a mild increase in pH and a decrease in Pco2 after TS. We conclude that TS in newborn rats is a regulator of circulating lactate. This response is maximal in the immediate postnatal period and wanes over the 1st wk of life. We speculate that the transduction of sensory signals by the skin is a mechanism regulating the availability of cerebral energy substrates in the newborn mammal. 相似文献
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JM Heward A Allahabadia J Daykin J Carr-Smith A Daly M Armitage PM Dodson MC Sheppard AH Barnett JA Franklyn SC Gough 《Canadian Metallurgical Quarterly》1998,83(10):3394-3397
Early case control studies found association of the DRB1 allele, DR3, with Graves' disease (GD). Recent reports, claim the DQA1 allele, DQA1*0501, to be the primary susceptibility determinant within the human leukocyte antigen (HLA) class II region. We typed 228 GD patients, 364 controls, and 98 families (parents, GD, and unaffected sibling) at the DRB1, DQB1, and DQA1 loci. The case control study showed an increased frequency in GD, compared to controls, of DRB1*0304 (47% vs. 24%; pc < 1.4 x 10(-5)), DQB1*02 (58% vs. 46%; pc < 0.035), DQB1*0301/4 (42% vs. 28%; pc < 3.5 x 10(-3)) and DQA1*0501 (67%, vs. 39%; pc < 7 x 10(-6)). The DRB1*0304-DQB1*02-DQA1*0501 haplotype was increased in GD (47%) vs. controls (24%; pc < 1.8 x 10(-5); odds ratio = 2.72). No independent association of these alleles was observed. Preferential transmission of DRB1*0304-DQB1*02-DQA1*0501 from parents heterozygous for the haplotype to GD siblings (72%) was seen in the families (chi2 = 11.95; 1 d.f.; P = 0.0005). Lack of preferential transmission to unaffected siblings (53%; chi2 = 0.19; 1 d.f.; P = NS) excluded segregation distortion. These results show that linkage disequilibrium between GD and the HLA class II region is due to the extended haplotype DRB1*0304-DQB1*02-DQA1*0501. 相似文献
959.
DR Meldrum X Meng BC Sheridan RC McIntyre AH Harken A Banerjee 《Canadian Metallurgical Quarterly》1998,9(4):256-260
Women with vulvar vestibulitis syndrome (VVS) suffer from severe pain and discomfort in the area around the introitus at almost any stimulus that causes pressure within the vestibule. In spite of the severe sensory symptoms present in these women, the influence of the peripheral nerves in the vulvar vestibulum has not been clarified before. In this study the nerve supply in the vestibular mucosa in women with VVS and in healthy women free from vulvar symptoms has been revealed by PGP 9.5 immunohistochemistry. The results show a significant increase in the number of intraepithelial nerve endings in women with VVS, indicating an alteration in the nerve supply in the afflicted area. 相似文献
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