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261.
PH Hoeger SS Adwani BF Whitehead AY Finlay JI Harper 《Canadian Metallurgical Quarterly》1998,139(6):1055-1059
We report two children with ichthyosiform erythroderma who at the ages of 9 weeks and 8 years, respectively, developed dilated cardiomyopathy, which was fatal in one and required heart transplantation in the other. A link between these conditions is considered likely, either as a primary genetic syndrome or secondary to micronutrient deficiency and/or infection. Owing to its insidious onset, cardiomyopathy may be overlooked, or symptoms attributed to the other conditions such as severe infections and failure to thrive that are common in these patients. We therefore recommend that children with congenital erythroderma are monitored closely, clinically and with echocardiography, for cardiomyopathy. 相似文献
262.
HC Spencer WE Collins M Warren GM Jeffery J Mason AY Huong PS Stanfill JC Skinner 《Canadian Metallurgical Quarterly》1981,30(4):747-750
Serum specimens from patients in El Salvador, Central America, with slide-proven Plasmodium falciparum infections were examined for antibodies to P. falciparum using the enzyme-linked immunosorbent assay (ELISA) and the indirect fluorescent antibody (IFA) methods. Both serologic tests were positive in 78.1% of the 827 samples, both negative in 5.4%, the ELISA positive alone in 6.3%, and the IFA alone in 10.2%. Agreement between the serologic tests was better in the specimens with high positive titers (high IFA = high ELISA). Seropositivity rates and geometric mean titers were higher in the older (greater than or equal to 15 years) age groups for both ELISA and IFA; in such persons, the IFA was positive in 92% and the ELISA in 88%. The lowest seropositivity rates found by the ELISA were observed in children; 27.6% of 98 children less than or equal to 4 years of age were negative. A longer duration of infection as evidenced by the presence of gametocytes on the blood slide resulted in higher positivity rates by both ELISA and IFA. This phenomenon, particularly apparent in young children, supports the belief that the more important variable in determining the proportion of false negatives is previous malaria experience and not age. The results indicate that, while neither serologic test is appropriate as a diagnostic aid, both the ELISA and the IFA would be useful in epidemiologic investigations. 相似文献
263.
AG Davies AY Game Z Chen TJ Williams S Goodall JL Yen JA McKenzie P Batterham 《Canadian Metallurgical Quarterly》1996,143(3):1321-1337
The Scalloped wings (Scl) gene of the Australian sheep blowfly, Lucilia cuprina, is shown to be the homologue of the Drosophila melanogaster Notch gene by comparison at the DNA sequence and genetic levels. A L. cuprina genomic fragment, which shows strong identity with the Notch (N) gene at the molecular level, hybridizes to the location of the Scl gene on polytene chromosomes. The two genes are functionally homologous; the dominant and recessive Notch-like phenotypes produced by mutations in the Scl gene allow these alleles to be classed as N-like or Abruptex-like. The Scl gene is under investigation as a candidate for the fitness and asymmetry Modifier (M) of diazinon resistance. We show that M affects the penetrance of wing and bristle phenotypes associated with two Scl alleles in a manner consistent with the M being an allele of Scl. In addition, we report a phenotypic interaction between the diazinon-resistance mutation, Rop-1, and the same alleles of Scl. We propose that the product of Rop-1, an esterase, may be involved in cell adhesion in developmental processes involving the Scl gene product. 相似文献
264.
265.
L-DOPA may cause side-effects during the treatment of Parkinson's disease. We investigated the role of glutathione peroxidase (GSHPx) in cellular defense against L-DOPA cytotoxicity. A line of PC12 cells overexpressing GSHPx with plasmid pRc/CMV-GSHPx was established and stable transfectants overexpressing GSHPx were used for this study. GSHPx activity was found to be 1.5-fold higher in GSHPx-transfectants than in mock-controlled transfectants. Transfectants over expressing GSHPx were also significantly more resistant to exposure to either L-DOPA or t-butyl hydroperoxide than mock-transfected cells. Results suggested that L-DOPA may cause neuronal cell death by an oxidative pathway and GSHPx may play an important role in cellular defense against oxidative stress. 相似文献
266.
267.
MILK COAGULATION CUT-TIME DETERMINATION USING ULTRASONICS 总被引:1,自引:0,他引:1
A nondestructive method of determining milk coagulation cut-time was investigated. Velocity and attenuation of ultrasonic waves through coagulating skim milk were measured after rennet addition. the ultrasonic attenuation measurements were found suitable for distinguishing the effect of different experimental variables (three levels of temperature, rennet and CaCl2 ). Based on the rate of change of attenuation during coagulation, a turning point was defined at which the attenuation rate change was -0.1 neper/m/min. the cut-time was proposed to be 20 min from the time the turning point was observed. the cut-times predicted by this criterion were statistically similar to those predicted by the manual method currently used in the industry. 相似文献